diff options
Diffstat (limited to 'drivers/firmware/arm_scmi')
| -rw-r--r-- | drivers/firmware/arm_scmi/Kconfig | 32 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/Makefile | 9 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/bus.c | 395 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/common.h | 100 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/driver.c | 1223 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/mailbox.c | 6 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/optee.c | 6 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/protocols.h | 7 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/raw_mode.c | 1443 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/raw_mode.h | 31 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/smc.c | 6 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/virtio.c | 4 |
12 files changed, 2703 insertions, 559 deletions
diff --git a/drivers/firmware/arm_scmi/Kconfig b/drivers/firmware/arm_scmi/Kconfig index a14f65444b35..ea0f5083ac47 100644 --- a/drivers/firmware/arm_scmi/Kconfig +++ b/drivers/firmware/arm_scmi/Kconfig @@ -23,6 +23,38 @@ config ARM_SCMI_PROTOCOL if ARM_SCMI_PROTOCOL +config ARM_SCMI_NEED_DEBUGFS + bool + help + This declares whether at least one SCMI facility is configured + which needs debugfs support. When selected causess the creation + of a common SCMI debugfs root directory. + +config ARM_SCMI_RAW_MODE_SUPPORT + bool "Enable support for SCMI Raw transmission mode" + depends on DEBUG_FS + select ARM_SCMI_NEED_DEBUGFS + help + Enable support for SCMI Raw transmission mode. + + If enabled allows the direct injection and snooping of SCMI bare + messages through a dedicated debugfs interface. + It is meant to be used by SCMI compliance/testing suites. + + When enabled regular SCMI drivers interactions are inhibited in + order to avoid unexpected interactions with the SCMI Raw message + flow. If unsure say N. + +config ARM_SCMI_RAW_MODE_SUPPORT_COEX + bool "Allow SCMI Raw mode coexistence with normal SCMI stack" + depends on ARM_SCMI_RAW_MODE_SUPPORT + help + Allow SCMI Raw transmission mode to coexist with normal SCMI stack. + + This will allow regular SCMI drivers to register with the core and + operate normally, thing which could make an SCMI test suite using the + SCMI Raw mode support unreliable. If unsure, say N. + config ARM_SCMI_HAVE_TRANSPORT bool help diff --git a/drivers/firmware/arm_scmi/Makefile b/drivers/firmware/arm_scmi/Makefile index 9ea86f8cc8f7..b31d78fa66cc 100644 --- a/drivers/firmware/arm_scmi/Makefile +++ b/drivers/firmware/arm_scmi/Makefile @@ -1,6 +1,9 @@ # SPDX-License-Identifier: GPL-2.0-only scmi-bus-y = bus.o +scmi-core-objs := $(scmi-bus-y) + scmi-driver-y = driver.o notify.o +scmi-driver-$(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT) += raw_mode.o scmi-transport-$(CONFIG_ARM_SCMI_HAVE_SHMEM) = shmem.o scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_MAILBOX) += mailbox.o scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_SMC) += smc.o @@ -8,9 +11,11 @@ scmi-transport-$(CONFIG_ARM_SCMI_HAVE_MSG) += msg.o scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_VIRTIO) += virtio.o scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_OPTEE) += optee.o scmi-protocols-y = base.o clock.o perf.o power.o reset.o sensors.o system.o voltage.o powercap.o -scmi-module-objs := $(scmi-bus-y) $(scmi-driver-y) $(scmi-protocols-y) \ - $(scmi-transport-y) +scmi-module-objs := $(scmi-driver-y) $(scmi-protocols-y) $(scmi-transport-y) + +obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-core.o obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-module.o + obj-$(CONFIG_ARM_SCMI_POWER_DOMAIN) += scmi_pm_domain.o obj-$(CONFIG_ARM_SCMI_POWER_CONTROL) += scmi_power_control.o diff --git a/drivers/firmware/arm_scmi/bus.c b/drivers/firmware/arm_scmi/bus.c index cc2eba067575..73140b854b31 100644 --- a/drivers/firmware/arm_scmi/bus.c +++ b/drivers/firmware/arm_scmi/bus.c @@ -7,8 +7,10 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include <linux/atomic.h> #include <linux/types.h> #include <linux/module.h> +#include <linux/of.h> #include <linux/kernel.h> #include <linux/slab.h> #include <linux/device.h> @@ -16,9 +18,174 @@ #include "common.h" +BLOCKING_NOTIFIER_HEAD(scmi_requested_devices_nh); +EXPORT_SYMBOL_GPL(scmi_requested_devices_nh); + static DEFINE_IDA(scmi_bus_id); -static DEFINE_IDR(scmi_protocols); -static DEFINE_SPINLOCK(protocol_lock); + +static DEFINE_IDR(scmi_requested_devices); +/* Protect access to scmi_requested_devices */ +static DEFINE_MUTEX(scmi_requested_devices_mtx); + +struct scmi_requested_dev { + const struct scmi_device_id *id_table; + struct list_head node; +}; + +/* Track globally the creation of SCMI SystemPower related devices */ +static atomic_t scmi_syspower_registered = ATOMIC_INIT(0); + +/** + * scmi_protocol_device_request - Helper to request a device + * + * @id_table: A protocol/name pair descriptor for the device to be created. + * + * This helper let an SCMI driver request specific devices identified by the + * @id_table to be created for each active SCMI instance. + * + * The requested device name MUST NOT be already existent for any protocol; + * at first the freshly requested @id_table is annotated in the IDR table + * @scmi_requested_devices and then the requested device is advertised to any + * registered party via the @scmi_requested_devices_nh notification chain. + * + * Return: 0 on Success + */ +static int scmi_protocol_device_request(const struct scmi_device_id *id_table) +{ + int ret = 0; + unsigned int id = 0; + struct list_head *head, *phead = NULL; + struct scmi_requested_dev *rdev; + + pr_debug("Requesting SCMI device (%s) for protocol %x\n", + id_table->name, id_table->protocol_id); + + if (IS_ENABLED(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT) && + !IS_ENABLED(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT_COEX)) { + pr_warn("SCMI Raw mode active. Rejecting '%s'/0x%02X\n", + id_table->name, id_table->protocol_id); + return -EINVAL; + } + + /* + * Search for the matching protocol rdev list and then search + * of any existent equally named device...fails if any duplicate found. + */ + mutex_lock(&scmi_requested_devices_mtx); + idr_for_each_entry(&scmi_requested_devices, head, id) { + if (!phead) { + /* A list found registered in the IDR is never empty */ + rdev = list_first_entry(head, struct scmi_requested_dev, + node); + if (rdev->id_table->protocol_id == + id_table->protocol_id) + phead = head; + } + list_for_each_entry(rdev, head, node) { + if (!strcmp(rdev->id_table->name, id_table->name)) { + pr_err("Ignoring duplicate request [%d] %s\n", + rdev->id_table->protocol_id, + rdev->id_table->name); + ret = -EINVAL; + goto out; + } + } + } + + /* + * No duplicate found for requested id_table, so let's create a new + * requested device entry for this new valid request. + */ + rdev = kzalloc(sizeof(*rdev), GFP_KERNEL); + if (!rdev) { + ret = -ENOMEM; + goto out; + } + rdev->id_table = id_table; + + /* + * Append the new requested device table descriptor to the head of the + * related protocol list, eventually creating such head if not already + * there. + */ + if (!phead) { + phead = kzalloc(sizeof(*phead), GFP_KERNEL); + if (!phead) { + kfree(rdev); + ret = -ENOMEM; + goto out; + } + INIT_LIST_HEAD(phead); + + ret = idr_alloc(&scmi_requested_devices, (void *)phead, + id_table->protocol_id, + id_table->protocol_id + 1, GFP_KERNEL); + if (ret != id_table->protocol_id) { + pr_err("Failed to save SCMI device - ret:%d\n", ret); + kfree(rdev); + kfree(phead); + ret = -EINVAL; + goto out; + } + ret = 0; + } + list_add(&rdev->node, phead); + +out: + mutex_unlock(&scmi_requested_devices_mtx); + + if (!ret) + blocking_notifier_call_chain(&scmi_requested_devices_nh, + SCMI_BUS_NOTIFY_DEVICE_REQUEST, + (void *)rdev->id_table); + + return ret; +} + +/** + * scmi_protocol_device_unrequest - Helper to unrequest a device + * + * @id_table: A protocol/name pair descriptor for the device to be unrequested. + * + * The unrequested device, described by the provided id_table, is at first + * removed from the IDR @scmi_requested_devices and then the removal is + * advertised to any registered party via the @scmi_requested_devices_nh + * notification chain. + */ +static void scmi_protocol_device_unrequest(const struct scmi_device_id *id_table) +{ + struct list_head *phead; + + pr_debug("Unrequesting SCMI device (%s) for protocol %x\n", + id_table->name, id_table->protocol_id); + + mutex_lock(&scmi_requested_devices_mtx); + phead = idr_find(&scmi_requested_devices, id_table->protocol_id); + if (phead) { + struct scmi_requested_dev *victim, *tmp; + + list_for_each_entry_safe(victim, tmp, phead, node) { + if (!strcmp(victim->id_table->name, id_table->name)) { + list_del(&victim->node); + + mutex_unlock(&scmi_requested_devices_mtx); + blocking_notifier_call_chain(&scmi_requested_devices_nh, + SCMI_BUS_NOTIFY_DEVICE_UNREQUEST, + (void *)victim->id_table); + kfree(victim); + mutex_lock(&scmi_requested_devices_mtx); + break; + } + } + + if (list_empty(phead)) { + idr_remove(&scmi_requested_devices, + id_table->protocol_id); + kfree(phead); + } + } + mutex_unlock(&scmi_requested_devices_mtx); +} static const struct scmi_device_id * scmi_dev_match_id(struct scmi_device *scmi_dev, struct scmi_driver *scmi_drv) @@ -58,11 +225,11 @@ static int scmi_match_by_id_table(struct device *dev, void *data) struct scmi_device_id *id_table = data; return sdev->protocol_id == id_table->protocol_id && - !strcmp(sdev->name, id_table->name); + (id_table->name && !strcmp(sdev->name, id_table->name)); } -struct scmi_device *scmi_child_dev_find(struct device *parent, - int prot_id, const char *name) +static struct scmi_device *scmi_child_dev_find(struct device *parent, + int prot_id, const char *name) { struct scmi_device_id id_table; struct device *dev; @@ -77,30 +244,6 @@ struct scmi_device *scmi_child_dev_find(struct device *parent, return to_scmi_dev(dev); } -const struct scmi_protocol *scmi_protocol_get(int protocol_id) -{ - const struct scmi_protocol *proto; - - proto = idr_find(&scmi_protocols, protocol_id); - if (!proto || !try_module_get(proto->owner)) { - pr_warn("SCMI Protocol 0x%x not found!\n", protocol_id); - return NULL; - } - - pr_debug("Found SCMI Protocol 0x%x\n", protocol_id); - - return proto; -} - -void scmi_protocol_put(int protocol_id) -{ - const struct scmi_protocol *proto; - - proto = idr_find(&scmi_protocols, protocol_id); - if (proto) - module_put(proto->owner); -} - static int scmi_dev_probe(struct device *dev) { struct scmi_driver *scmi_drv = to_scmi_driver(dev->driver); @@ -121,12 +264,13 @@ static void scmi_dev_remove(struct device *dev) scmi_drv->remove(scmi_dev); } -static struct bus_type scmi_bus_type = { +struct bus_type scmi_bus_type = { .name = "scmi_protocol", .match = scmi_dev_match, .probe = scmi_dev_probe, .remove = scmi_dev_remove, }; +EXPORT_SYMBOL_GPL(scmi_bus_type); int scmi_driver_register(struct scmi_driver *driver, struct module *owner, const char *mod_name) @@ -147,7 +291,7 @@ int scmi_driver_register(struct scmi_driver *driver, struct module *owner, retval = driver_register(&driver->driver); if (!retval) - pr_debug("registered new scmi driver %s\n", driver->name); + pr_debug("Registered new scmi driver %s\n", driver->name); return retval; } @@ -165,13 +309,53 @@ static void scmi_device_release(struct device *dev) kfree(to_scmi_dev(dev)); } -struct scmi_device * -scmi_device_create(struct device_node *np, struct device *parent, int protocol, - const char *name) +static void __scmi_device_destroy(struct scmi_device *scmi_dev) +{ + pr_debug("(%s) Destroying SCMI device '%s' for protocol 0x%x (%s)\n", + of_node_full_name(scmi_dev->dev.parent->of_node), + dev_name(&scmi_dev->dev), scmi_dev->protocol_id, + scmi_dev->name); + + if (scmi_dev->protocol_id == SCMI_PROTOCOL_SYSTEM) + atomic_set(&scmi_syspower_registered, 0); + + kfree_const(scmi_dev->name); + ida_free(&scmi_bus_id, scmi_dev->id); + device_unregister(&scmi_dev->dev); +} + +static struct scmi_device * +__scmi_device_create(struct device_node *np, struct device *parent, + int protocol, const char *name) { int id, retval; struct scmi_device *scmi_dev; + /* + * If the same protocol/name device already exist under the same parent + * (i.e. SCMI instance) just return the existent device. + * This avoids any race between the SCMI driver, creating devices for + * each DT defined protocol at probe time, and the concurrent + * registration of SCMI drivers. + */ + scmi_dev = scmi_child_dev_find(parent, protocol, name); + if (scmi_dev) + return scmi_dev; + + /* + * Ignore any possible subsequent failures while creating the device + * since we are doomed anyway at that point; not using a mutex which + * spans across this whole function to keep things simple and to avoid + * to serialize all the __scmi_device_create calls across possibly + * different SCMI server instances (parent) + */ + if (protocol == SCMI_PROTOCOL_SYSTEM && + atomic_cmpxchg(&scmi_syspower_registered, 0, 1)) { + dev_warn(parent, + "SCMI SystemPower protocol device must be unique !\n"); + return NULL; + } + scmi_dev = kzalloc(sizeof(*scmi_dev), GFP_KERNEL); if (!scmi_dev) return NULL; @@ -201,6 +385,10 @@ scmi_device_create(struct device_node *np, struct device *parent, int protocol, if (retval) goto put_dev; + pr_debug("(%s) Created SCMI device '%s' for protocol 0x%x (%s)\n", + of_node_full_name(parent->of_node), + dev_name(&scmi_dev->dev), protocol, name); + return scmi_dev; put_dev: kfree_const(scmi_dev->name); @@ -209,77 +397,85 @@ put_dev: return NULL; } -void scmi_device_destroy(struct scmi_device *scmi_dev) -{ - kfree_const(scmi_dev->name); - scmi_handle_put(scmi_dev->handle); - ida_free(&scmi_bus_id, scmi_dev->id); - device_unregister(&scmi_dev->dev); -} - -void scmi_device_link_add(struct device *consumer, struct device *supplier) -{ - struct device_link *link; - - link = device_link_add(consumer, supplier, DL_FLAG_AUTOREMOVE_CONSUMER); - - WARN_ON(!link); -} - -void scmi_set_handle(struct scmi_device *scmi_dev) -{ - scmi_dev->handle = scmi_handle_get(&scmi_dev->dev); - if (scmi_dev->handle) - scmi_device_link_add(&scmi_dev->dev, scmi_dev->handle->dev); -} - -int scmi_protocol_register(const struct scmi_protocol *proto) +/** + * scmi_device_create - A method to create one or more SCMI devices + * + * @np: A reference to the device node to use for the new device(s) + * @parent: The parent device to use identifying a specific SCMI instance + * @protocol: The SCMI protocol to be associated with this device + * @name: The requested-name of the device to be created; this is optional + * and if no @name is provided, all the devices currently known to + * be requested on the SCMI bus for @protocol will be created. + * + * This method can be invoked to create a single well-defined device (like + * a transport device or a device requested by an SCMI driver loaded after + * the core SCMI stack has been probed), or to create all the devices currently + * known to have been requested by the loaded SCMI drivers for a specific + * protocol (typically during SCMI core protocol enumeration at probe time). + * + * Return: The created device (or one of them if @name was NOT provided and + * multiple devices were created) or NULL if no device was created; + * note that NULL indicates an error ONLY in case a specific @name + * was provided: when @name param was not provided, a number of devices + * could have been potentially created for a whole protocol, unless no + * device was found to have been requested for that specific protocol. + */ +struct scmi_device *scmi_device_create(struct device_node *np, + struct device *parent, int protocol, + const char *name) { - int ret; - - if (!proto) { - pr_err("invalid protocol\n"); - return -EINVAL; - } - - if (!proto->instance_init) { - pr_err("missing init for protocol 0x%x\n", proto->id); - return -EINVAL; + struct list_head *phead; + struct scmi_requested_dev *rdev; + struct scmi_device *scmi_dev = NULL; + + if (name) + return __scmi_device_create(np, parent, protocol, name); + + mutex_lock(&scmi_requested_devices_mtx); + phead = idr_find(&scmi_requested_devices, protocol); + /* Nothing to do. */ + if (!phead) { + mutex_unlock(&scmi_requested_devices_mtx); + return scmi_dev; } - spin_lock(&protocol_lock); - ret = idr_alloc(&scmi_protocols, (void *)proto, - proto->id, proto->id + 1, GFP_ATOMIC); - spin_unlock(&protocol_lock); - if (ret != proto->id) { - pr_err("unable to allocate SCMI idr slot for 0x%x - err %d\n", - proto->id, ret); - return ret; + /* Walk the list of requested devices for protocol and create them */ + list_for_each_entry(rdev, phead, node) { + struct scmi_device *sdev; + + sdev = __scmi_device_create(np, parent, + rdev->id_table->protocol_id, + rdev->id_table->name); + /* Report errors and carry on... */ + if (sdev) + scmi_dev = sdev; + else + pr_err("(%s) Failed to create device for protocol 0x%x (%s)\n", + of_node_full_name(parent->of_node), + rdev->id_table->protocol_id, + rdev->id_table->name); } + mutex_unlock(&scmi_requested_devices_mtx); - pr_debug("Registered SCMI Protocol 0x%x\n", proto->id); - - return 0; + return scmi_dev; } -EXPORT_SYMBOL_GPL(scmi_protocol_register); +EXPORT_SYMBOL_GPL(scmi_device_create); -void scmi_protocol_unregister(const struct scmi_protocol *proto) +void scmi_device_destroy(struct device *parent, int protocol, const char *name) { - spin_lock(&protocol_lock); - idr_remove(&scmi_protocols, proto->id); - spin_unlock(&protocol_lock); - - pr_debug("Unregistered SCMI Protocol 0x%x\n", proto->id); + struct scmi_device *scmi_dev; - return; + scmi_dev = scmi_child_dev_find(parent, protocol, name); + if (scmi_dev) + __scmi_device_destroy(scmi_dev); } -EXPORT_SYMBOL_GPL(scmi_protocol_unregister); +EXPORT_SYMBOL_GPL(scmi_device_destroy); static int __scmi_devices_unregister(struct device *dev, void *data) { struct scmi_device *scmi_dev = to_scmi_dev(dev); - scmi_device_destroy(scmi_dev); + __scmi_device_destroy(scmi_dev); return 0; } @@ -288,20 +484,33 @@ static void scmi_devices_unregister(void) bus_for_each_dev(&scmi_bus_type, NULL, NULL, __scmi_devices_unregister); } -int __init scmi_bus_init(void) +static int __init scmi_bus_init(void) { int retval; retval = bus_register(&scmi_bus_type); if (retval) - pr_err("scmi protocol bus register failed (%d)\n", retval); + pr_err("SCMI protocol bus register failed (%d)\n", retval); + + pr_info("SCMI protocol bus registered\n"); return retval; } +subsys_initcall(scmi_bus_init); -void __exit scmi_bus_exit(void) +static void __exit scmi_bus_exit(void) { + /* + * Destroy all remaining devices: just in case the drivers were + * manually unbound and at first and then the modules unloaded. + */ scmi_devices_unregister(); bus_unregister(&scmi_bus_type); ida_destroy(&scmi_bus_id); } +module_exit(scmi_bus_exit); + +MODULE_ALIAS("scmi-core"); +MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>"); +MODULE_DESCRIPTION("ARM SCMI protocol bus"); +MODULE_LICENSE("GPL"); diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h index a1c0154c31c6..c46dc5215af7 100644 --- a/drivers/firmware/arm_scmi/common.h +++ b/drivers/firmware/arm_scmi/common.h @@ -27,6 +27,48 @@ #include "protocols.h" #include "notify.h" +#define SCMI_MAX_CHANNELS 256 + +#define SCMI_MAX_RESPONSE_TIMEOUT (2 * MSEC_PER_SEC) + +enum scmi_error_codes { + SCMI_SUCCESS = 0, /* Success */ + SCMI_ERR_SUPPORT = -1, /* Not supported */ + SCMI_ERR_PARAMS = -2, /* Invalid Parameters */ + SCMI_ERR_ACCESS = -3, /* Invalid access/permission denied */ + SCMI_ERR_ENTRY = -4, /* Not found */ + SCMI_ERR_RANGE = -5, /* Value out of range */ + SCMI_ERR_BUSY = -6, /* Device busy */ + SCMI_ERR_COMMS = -7, /* Communication Error */ + SCMI_ERR_GENERIC = -8, /* Generic Error */ + SCMI_ERR_HARDWARE = -9, /* Hardware Error */ + SCMI_ERR_PROTOCOL = -10,/* Protocol Error */ +}; + +static const int scmi_linux_errmap[] = { + /* better than switch case as long as return value is continuous */ + 0, /* SCMI_SUCCESS */ + -EOPNOTSUPP, /* SCMI_ERR_SUPPORT */ + -EINVAL, /* SCMI_ERR_PARAM */ + -EACCES, /* SCMI_ERR_ACCESS */ + -ENOENT, /* SCMI_ERR_ENTRY */ + -ERANGE, /* SCMI_ERR_RANGE */ + -EBUSY, /* SCMI_ERR_BUSY */ + -ECOMM, /* SCMI_ERR_COMMS */ + -EIO, /* SCMI_ERR_GENERIC */ + -EREMOTEIO, /* SCMI_ERR_HARDWARE */ + -EPROTO, /* SCMI_ERR_PROTOCOL */ +}; + +static inline int scmi_to_linux_errno(int errno) +{ + int err_idx = -errno; + + if (err_idx >= SCMI_SUCCESS && err_idx < ARRAY_SIZE(scmi_linux_errmap)) + return scmi_linux_errmap[err_idx]; + return -EIO; +} + #define MSG_ID_MASK GENMASK(7, 0) #define MSG_XTRACT_ID(hdr) FIELD_GET(MSG_ID_MASK, (hdr)) #define MSG_TYPE_MASK GENMASK(9, 8) @@ -96,18 +138,19 @@ static inline void unpack_scmi_header(u32 msg_hdr, struct scmi_msg_hdr *hdr) struct scmi_revision_info * scmi_revision_area_get(const struct scmi_protocol_handle *ph); -int scmi_handle_put(const struct scmi_handle *handle); -void scmi_device_link_add(struct device *consumer, struct device *supplier); -struct scmi_handle *scmi_handle_get(struct device *dev); -void scmi_set_handle(struct scmi_device *scmi_dev); void scmi_setup_protocol_implemented(const struct scmi_protocol_handle *ph, u8 *prot_imp); -int __init scmi_bus_init(void); -void __exit scmi_bus_exit(void); +extern struct bus_type scmi_bus_type; + +#define SCMI_BUS_NOTIFY_DEVICE_REQUEST 0 +#define SCMI_BUS_NOTIFY_DEVICE_UNREQUEST 1 +extern struct blocking_notifier_head scmi_requested_devices_nh; -const struct scmi_protocol *scmi_protocol_get(int protocol_id); -void scmi_protocol_put(int protocol_id); +struct scmi_device *scmi_device_create(struct device_node *np, + struct device *parent, int protocol, + const char *name); +void scmi_device_destroy(struct device *parent, int protocol, const char *name); int scmi_protocol_acquire(const struct scmi_handle *handle, u8 protocol_id); void scmi_protocol_release(const struct scmi_handle *handle, u8 protocol_id); @@ -116,6 +159,8 @@ void scmi_protocol_release(const struct scmi_handle *handle, u8 protocol_id); /** * struct scmi_chan_info - Structure representing a SCMI channel information * + * @id: An identifier for this channel: this matches the protocol number + * used to initialize this channel * @dev: Reference to device in the SCMI hierarchy corresponding to this * channel * @rx_timeout_ms: The configured RX timeout in milliseconds. @@ -127,6 +172,7 @@ void scmi_protocol_release(const struct scmi_handle *handle, u8 protocol_id); * @transport_info: Transport layer related information */ struct scmi_chan_info { + int id; struct device *dev; unsigned int rx_timeout_ms; struct scmi_handle *handle; @@ -153,7 +199,7 @@ struct scmi_chan_info { */ struct scmi_transport_ops { int (*link_supplier)(struct device *dev); - bool (*chan_available)(struct device *dev, int idx); + bool (*chan_available)(struct device_node *of_node, int idx); int (*chan_setup)(struct scmi_chan_info *cinfo, struct device *dev, bool tx); int (*chan_free)(int id, void *p, void *data); @@ -170,11 +216,6 @@ struct scmi_transport_ops { bool (*poll_done)(struct scmi_chan_info *cinfo, struct scmi_xfer *xfer); }; -int scmi_protocol_device_request(const struct scmi_device_id *id_table); -void scmi_protocol_device_unrequest(const struct scmi_device_id *id_table); -struct scmi_device *scmi_child_dev_find(struct device *parent, - int prot_id, const char *name); - /** * struct scmi_desc - Description of SoC integration * @@ -215,6 +256,36 @@ struct scmi_desc { const bool atomic_enabled; }; +static inline bool is_polling_required(struct scmi_chan_info *cinfo, + const struct scmi_desc *desc) +{ + return cinfo->no_completion_irq || desc->force_polling; +} + +static inline bool is_transport_polling_capable(const struct scmi_desc *desc) +{ + return desc->ops->poll_done || desc->sync_cmds_completed_on_ret; +} + +static inline bool is_polling_enabled(struct scmi_chan_info *cinfo, + const struct scmi_desc *desc) +{ + return is_polling_required(cinfo, desc) && + is_transport_polling_capable(desc); +} + +void scmi_xfer_raw_put(const struct scmi_handle *handle, + struct scmi_xfer *xfer); +struct scmi_xfer *scmi_xfer_raw_get(const struct scmi_handle *handle); +struct scmi_chan_info * +scmi_xfer_raw_channel_get(const struct scmi_handle *handle, u8 protocol_id); + +int scmi_xfer_raw_inflight_register(const struct scmi_handle *handle, + struct scmi_xfer *xfer); + +int scmi_xfer_raw_wait_for_message_response(struct scmi_chan_info *cinfo, + struct scmi_xfer *xfer, + unsigned int timeout_ms); #ifdef CONFIG_ARM_SCMI_TRANSPORT_MAILBOX extern const struct scmi_desc scmi_mailbox_desc; #endif @@ -229,7 +300,6 @@ extern const struct scmi_desc scmi_optee_desc; #endif void scmi_rx_callback(struct scmi_chan_info *cinfo, u32 msg_hdr, void *priv); -void scmi_free_channel(struct scmi_chan_info *cinfo, struct idr *idr, int id); /* shmem related declarations */ struct scmi_shared_mem; diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c index ffdad59ec81f..d21c7eafd641 100644 --- a/drivers/firmware/arm_scmi/driver.c +++ b/drivers/firmware/arm_scmi/driver.c @@ -14,7 +14,10 @@ * Copyright (C) 2018-2021 ARM Ltd. */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + #include <linux/bitmap.h> +#include <linux/debugfs.h> #include <linux/device.h> #include <linux/export.h> #include <linux/idr.h> @@ -34,22 +37,15 @@ #include "common.h" #include "notify.h" +#include "raw_mode.h" + #define CREATE_TRACE_POINTS #include <trace/events/scmi.h> -enum scmi_error_codes { - SCMI_SUCCESS = 0, /* Success */ - SCMI_ERR_SUPPORT = -1, /* Not supported */ - SCMI_ERR_PARAMS = -2, /* Invalid Parameters */ - SCMI_ERR_ACCESS = -3, /* Invalid access/permission denied */ - SCMI_ERR_ENTRY = -4, /* Not found */ - SCMI_ERR_RANGE = -5, /* Value out of range */ - SCMI_ERR_BUSY = -6, /* Device busy */ - SCMI_ERR_COMMS = -7, /* Communication Error */ - SCMI_ERR_GENERIC = -8, /* Generic Error */ - SCMI_ERR_HARDWARE = -9, /* Hardware Error */ - SCMI_ERR_PROTOCOL = -10,/* Protocol Error */ -}; +static DEFINE_IDA(scmi_id); + +static DEFINE_IDR(scmi_protocols); +static DEFINE_SPINLOCK(protocol_lock); /* List of all SCMI devices active in system */ static LIST_HEAD(scmi_list); @@ -58,18 +54,7 @@ static DEFINE_MUTEX(scmi_list_mutex); /* Track the unique id for the transfers for debug & profiling purpose */ static atomic_t transfer_last_id; -static DEFINE_IDR(scmi_requested_devices); -static DEFINE_MUTEX(scmi_requested_devices_mtx); - -/* Track globally the creation of SCMI SystemPower related devices */ -static bool scmi_syspower_registered; -/* Protect access to scmi_syspower_registered */ -static DEFINE_MUTEX(scmi_syspower_mtx); - -struct scmi_requested_dev { - const struct scmi_device_id *id_table; - struct list_head node; -}; +static struct dentry *scmi_top_dentry; /** * struct scmi_xfers_info - Structure to manage transfer information @@ -118,8 +103,23 @@ struct scmi_protocol_instance { #define ph_to_pi(h) container_of(h, struct scmi_protocol_instance, ph) /** + * struct scmi_debug_info - Debug common info + * @top_dentry: A reference to the top debugfs dentry + * @name: Name of this SCMI instance + * @type: Type of this SCMI instance + * @is_atomic: Flag to state if the transport of this instance is atomic + */ +struct scmi_debug_info { + struct dentry *top_dentry; + const char *name; + const char *type; + bool is_atomic; +}; + +/** * struct scmi_info - Structure representing a SCMI instance * + * @id: A sequence number starting from zero identifying this instance * @dev: Device pointer * @desc: SoC description for this instance * @version: SCMI revision information containing protocol version, @@ -147,8 +147,15 @@ struct scmi_protocol_instance { * @notify_priv: Pointer to private data structure specific to notifications. * @node: List head * @users: Number of users of this instance + * @bus_nb: A notifier to listen for device bind/unbind on the scmi bus + * @dev_req_nb: A notifier to listen for device request/unrequest on the scmi + * bus + * @devreq_mtx: A mutex to serialize device creation for this SCMI instance + * @dbg: A pointer to debugfs related data (if any) + * @raw: An opaque reference handle used by SCMI Raw mode. */ struct scmi_info { + int id; struct device *dev; const struct scmi_desc *desc; struct scmi_revision_info version; @@ -166,32 +173,114 @@ struct scmi_info { void *notify_priv; struct list_head node; int users; + struct notifier_block bus_nb; + struct notifier_block dev_req_nb; + /* Serialize device creation process for this instance */ + struct mutex devreq_mtx; + struct scmi_debug_info *dbg; + void *raw; }; #define handle_to_scmi_info(h) container_of(h, struct scmi_info, handle) +#define bus_nb_to_scmi_info(nb) container_of(nb, struct scmi_info, bus_nb) +#define req_nb_to_scmi_info(nb) container_of(nb, struct scmi_info, dev_req_nb) -static const int scmi_linux_errmap[] = { - /* better than switch case as long as return value is continuous */ - 0, /* SCMI_SUCCESS */ - -EOPNOTSUPP, /* SCMI_ERR_SUPPORT */ - -EINVAL, /* SCMI_ERR_PARAM */ - -EACCES, /* SCMI_ERR_ACCESS */ - -ENOENT, /* SCMI_ERR_ENTRY */ - -ERANGE, /* SCMI_ERR_RANGE */ - -EBUSY, /* SCMI_ERR_BUSY */ - -ECOMM, /* SCMI_ERR_COMMS */ - -EIO, /* SCMI_ERR_GENERIC */ - -EREMOTEIO, /* SCMI_ERR_HARDWARE */ - -EPROTO, /* SCMI_ERR_PROTOCOL */ -}; +static const struct scmi_protocol *scmi_protocol_get(int protocol_id) +{ + const struct scmi_protocol *proto; + + proto = idr_find(&scmi_protocols, protocol_id); + if (!proto || !try_module_get(proto->owner)) { + pr_warn("SCMI Protocol 0x%x not found!\n", protocol_id); + return NULL; + } + + pr_debug("Found SCMI Protocol 0x%x\n", protocol_id); + + return proto; +} + +static void scmi_protocol_put(int protocol_id) +{ + const struct scmi_protocol *proto; + + proto = idr_find(&scmi_protocols, protocol_id); + if (proto) + module_put(proto->owner); +} + +int scmi_protocol_register(const struct scmi_protocol *proto) +{ + int ret; + + if (!proto) { + pr_err("invalid protocol\n"); + return -EINVAL; + } + + if (!proto->instance_init) { + pr_err("missing init for protocol 0x%x\n", proto->id); + return -EINVAL; + } + + spin_lock(&protocol_lock); + ret = idr_alloc(&scmi_protocols, (void *)proto, + proto->id, proto->id + 1, GFP_ATOMIC); + spin_unlock(&protocol_lock); + if (ret != proto->id) { + pr_err("unable to allocate SCMI idr slot for 0x%x - err %d\n", + proto->id, ret); + return ret; + } + + pr_debug("Registered SCMI Protocol 0x%x\n", proto->id); + + return 0; +} +EXPORT_SYMBOL_GPL(scmi_protocol_register); + +void scmi_protocol_unregister(const struct scmi_protocol *proto) +{ + spin_lock(&protocol_lock); + idr_remove(&scmi_protocols, proto->id); + spin_unlock(&protocol_lock); -static inline int scmi_to_linux_errno(int errno) + pr_debug("Unregistered SCMI Protocol 0x%x\n", proto->id); +} +EXPORT_SYMBOL_GPL(scmi_protocol_unregister); + +/** + * scmi_create_protocol_devices - Create devices for all pending requests for + * this SCMI instance. + * + * @np: The device node describing the protocol + * @info: The SCMI instance descriptor + * @prot_id: The protocol ID + * @name: The optional name of the device to be created: if not provided this + * call will lead to the creation of all the devices currently requested + * for the specified protocol. + */ +static void scmi_create_protocol_devices(struct device_node *np, + struct scmi_info *info, + int prot_id, const char *name) { - int err_idx = -errno; + struct scmi_device *sdev; - if (err_idx >= SCMI_SUCCESS && err_idx < ARRAY_SIZE(scmi_linux_errmap)) - return scmi_linux_errmap[err_idx]; - return -EIO; + mutex_lock(&info->devreq_mtx); + sdev = scmi_device_create(np, info->dev, prot_id, name); + if (name && !sdev) + dev_err(info->dev, + "failed to create device for protocol 0x%X (%s)\n", + prot_id, name); + mutex_unlock(&info->devreq_mtx); +} + +static void scmi_destroy_protocol_devices(struct scmi_info *info, + int prot_id, const char *name) +{ + mutex_lock(&info->devreq_mtx); + scmi_device_destroy(info->dev, prot_id, name); + mutex_unlock(&info->devreq_mtx); } void scmi_notification_instance_data_set(const struct scmi_handle *handle, @@ -311,8 +400,6 @@ static int scmi_xfer_token_set(struct scmi_xfers_info *minfo, if (xfer_id != next_token) atomic_add((int)(xfer_id - next_token), &transfer_last_id); - /* Set in-flight */ - set_bit(xfer_id, minfo->xfer_alloc_table); xfer->hdr.seq = (u16)xfer_id; return 0; @@ -331,32 +418,123 @@ static inline void scmi_xfer_token_clear(struct scmi_xfers_info *minfo, } /** + * scmi_xfer_inflight_register_unlocked - Register the xfer as in-flight + * + * @xfer: The xfer to register + * @minfo: Pointer to Tx/Rx Message management info based on channel type + * + * Note that this helper assumes that the xfer to be registered as in-flight + * had been built using an xfer sequence number which still corresponds to a + * free slot in the xfer_alloc_table. + * + * Context: Assumes to be called with @xfer_lock already acquired. + */ +static inline void +scmi_xfer_inflight_register_unlocked(struct scmi_xfer *xfer, + struct scmi_xfers_info *minfo) +{ + /* Set in-flight */ + set_bit(xfer->hdr.seq, minfo->xfer_alloc_table); + hash_add(minfo->pending_xfers, &xfer->node, xfer->hdr.seq); + xfer->pending = true; +} + +/** + * scmi_xfer_inflight_register - Try to register an xfer as in-flight + * + * @xfer: The xfer to register + * @minfo: Pointer to Tx/Rx Message management info based on channel type + * + * Note that this helper does NOT assume anything about the sequence number + * that was baked into the provided xfer, so it checks at first if it can + * be mapped to a free slot and fails with an error if another xfer with the + * same sequence number is currently still registered as in-flight. + * + * Return: 0 on Success or -EBUSY if sequence number embedded in the xfer + * could not rbe mapped to a free slot in the xfer_alloc_table. + */ +static int scmi_xfer_inflight_register(struct scmi_xfer *xfer, + struct scmi_xfers_info *minfo) +{ + int ret = 0; + unsigned long flags; + + spin_lock_irqsave(&minfo->xfer_lock, flags); + if (!test_bit(xfer->hdr.seq, minfo->xfer_alloc_table)) + scmi_xfer_inflight_register_unlocked(xfer, minfo); + else + ret = -EBUSY; + spin_unlock_irqrestore(&minfo->xfer_lock, flags); + + return ret; +} + +/** + * scmi_xfer_raw_inflight_register - An helper to register the given xfer as in + * flight on the TX channel, if possible. + * + * @handle: Pointer to SCMI entity handle + * @xfer: The xfer to register + * + * Return: 0 on Success, error otherwise + */ +int scmi_xfer_raw_inflight_register(const struct scmi_handle *handle, + struct scmi_xfer *xfer) +{ + struct scmi_info *info = handle_to_scmi_info(handle); + + return scmi_xfer_inflight_register(xfer, &info->tx_minfo); +} + +/** + * scmi_xfer_pending_set - Pick a proper sequence number and mark the xfer + * as pending in-flight + * + * @xfer: The xfer to act upon + * @minfo: Pointer to Tx/Rx Message management info based on channel type + * + * Return: 0 on Success or error otherwise + */ +static inline int scmi_xfer_pending_set(struct scmi_xfer *xfer, + struct scmi_xfers_info *minfo) +{ + int ret; + unsigned long flags; + + spin_lock_irqsave(&minfo->xfer_lock, flags); + /* Set a new monotonic token as the xfer sequence number */ + ret = scmi_xfer_token_set(minfo, xfer); + if (!ret) + scmi_xfer_inflight_register_unlocked(xfer, minfo); + spin_unlock_irqrestore(&minfo->xfer_lock, flags); + + return ret; +} + +/** * scmi_xfer_get() - Allocate one message * * @handle: Pointer to SCMI entity handle * @minfo: Pointer to Tx/Rx Message management info based on channel type - * @set_pending: If true a monotonic token is picked and the xfer is added to - * the pending hash table. * * Helper function which is used by various message functions that are * exposed to clients of this driver for allocating a message traffic event. * - * Picks an xfer from the free list @free_xfers (if any available) and, if - * required, sets a monotonically increasing token and stores the inflight xfer - * into the @pending_xfers hashtable for later retrieval. + * Picks an xfer from the free list @free_xfers (if any available) and perform + * a basic initialization. + * + * Note that, at this point, still no sequence number is assigned to the + * allocated xfer, nor it is registered as a pending transaction. * * The successfully initialized xfer is refcounted. * - * Context: Holds @xfer_lock while manipulating @xfer_alloc_table and - * @free_xfers. + * Context: Holds @xfer_lock while manipulating @free_xfers. * - * Return: 0 if all went fine, else corresponding error. + * Return: An initialized xfer if all went fine, else pointer error. */ static struct scmi_xfer *scmi_xfer_get(const struct scmi_handle *handle, - struct scmi_xfers_info *minfo, - bool set_pending) + struct scmi_xfers_info *minfo) { - int ret; unsigned long flags; struct scmi_xfer *xfer; @@ -376,31 +554,71 @@ static struct scmi_xfer *scmi_xfer_get(const struct scmi_handle *handle, */ xfer->transfer_id = atomic_inc_return(&transfer_last_id); - if (set_pending) { - /* Pick and set monotonic token */ - ret = scmi_xfer_token_set(minfo, xfer); - if (!ret) { - hash_add(minfo->pending_xfers, &xfer->node, - xfer->hdr.seq); - xfer->pending = true; - } else { - dev_err(handle->dev, - "Failed to get monotonic token %d\n", ret); - hlist_add_head(&xfer->node, &minfo->free_xfers); - xfer = ERR_PTR(ret); - } - } - - if (!IS_ERR(xfer)) { - refcount_set(&xfer->users, 1); - atomic_set(&xfer->busy, SCMI_XFER_FREE); - } + refcount_set(&xfer->users, 1); + atomic_set(&xfer->busy, SCMI_XFER_FREE); spin_unlock_irqrestore(&minfo->xfer_lock, flags); return xfer; } /** + * scmi_xfer_raw_get - Helper to get a bare free xfer from the TX channel + * + * @handle: Pointer to SCMI entity handle + * + * Note that xfer is taken from the TX channel structures. + * + * Return: A valid xfer on Success, or an error-pointer otherwise + */ +struct scmi_xfer *scmi_xfer_raw_get(const struct scmi_handle *handle) +{ + struct scmi_xfer *xfer; + struct scmi_info *info = handle_to_scmi_info(handle); + + xfer = scmi_xfer_get(handle, &info->tx_minfo); + if (!IS_ERR(xfer)) + xfer->flags |= SCMI_XFER_FLAG_IS_RAW; + + return xfer; +} + +/** + * scmi_xfer_raw_channel_get - Helper to get a reference to the proper channel + * to use for a specific protocol_id Raw transaction. + * + * @handle: Pointer to SCMI entity handle + * @protocol_id: Identifier of the protocol + * + * Note that in a regular SCMI stack, usually, a protocol has to be defined in + * the DT to have an associated channel and be usable; but in Raw mode any + * protocol in range is allowed, re-using the Base channel, so as to enable + * fuzzing on any protocol without the need of a fully compiled DT. + * + * Return: A reference to the channel to use, or an ERR_PTR + */ +struct scmi_chan_info * +scmi_xfer_raw_channel_get(const struct scmi_handle *handle, u8 protocol_id) +{ + struct scmi_chan_info *cinfo; + struct scmi_info *info = handle_to_scmi_info(handle); + + cinfo = idr_find(&info->tx_idr, protocol_id); + if (!cinfo) { + if (protocol_id == SCMI_PROTOCOL_BASE) + return ERR_PTR(-EINVAL); + /* Use Base channel for protocols not defined for DT */ + cinfo = idr_find(&info->tx_idr, SCMI_PROTOCOL_BASE); + if (!cinfo) + return ERR_PTR(-EINVAL); + dev_warn_once(handle->dev, + "Using Base channel for protocol 0x%X\n", + protocol_id); + } + + return cinfo; +} + +/** * __scmi_xfer_put() - Release a message * * @minfo: Pointer to Tx/Rx Message management info based on channel type @@ -429,6 +647,24 @@ __scmi_xfer_put(struct scmi_xfers_info *minfo, struct scmi_xfer *xfer) } /** + * scmi_xfer_raw_put - Release an xfer that was taken by @scmi_xfer_raw_get + * + * @handle: Pointer to SCMI entity handle + * @xfer: A reference to the xfer to put + * + * Note that as with other xfer_put() handlers the xfer is really effectively + * released only if there are no more users on the system. + */ +void scmi_xfer_raw_put(const struct scmi_handle *handle, struct scmi_xfer *xfer) +{ + struct scmi_info *info = handle_to_scmi_info(handle); + + xfer->flags &= ~SCMI_XFER_FLAG_IS_RAW; + xfer->flags &= ~SCMI_XFER_FLAG_CHAN_SET; + return __scmi_xfer_put(&info->tx_minfo, xfer); +} + +/** * scmi_xfer_lookup_unlocked - Helper to lookup an xfer_id * * @minfo: Pointer to Tx/Rx Message management info based on channel type @@ -623,25 +859,6 @@ static inline void scmi_clear_channel(struct scmi_info *info, info->desc->ops->clear_channel(cinfo); } -static inline bool is_polling_required(struct scmi_chan_info *cinfo, - struct scmi_info *info) -{ - return cinfo->no_completion_irq || info->desc->force_polling; -} - -static inline bool is_transport_polling_capable(struct scmi_info *info) -{ - return info->desc->ops->poll_done || - info->desc->sync_cmds_completed_on_ret; -} - -static inline bool is_polling_enabled(struct scmi_chan_info *cinfo, - struct scmi_info *info) -{ - return is_polling_required(cinfo, info) && - is_transport_polling_capable(info); -} - static void scmi_handle_notification(struct scmi_chan_info *cinfo, u32 msg_hdr, void *priv) { @@ -652,7 +869,7 @@ static void scmi_handle_notification(struct scmi_chan_info *cinfo, ktime_t ts; ts = ktime_get_boottime(); - xfer = scmi_xfer_get(cinfo->handle, minfo, false); + xfer = scmi_xfer_get(cinfo->handle, minfo); if (IS_ERR(xfer)) { dev_err(dev, "failed to get free message slot (%ld)\n", PTR_ERR(xfer)); @@ -667,9 +884,9 @@ static void scmi_handle_notification(struct scmi_chan_info *cinfo, info->desc->ops->fetch_notification(cinfo, info->desc->max_msg_size, xfer); - trace_scmi_msg_dump(xfer->hdr.protocol_id, xfer->hdr.id, "NOTI", - xfer->hdr.seq, xfer->hdr.status, - xfer->rx.buf, xfer->rx.len); + trace_scmi_msg_dump(info->id, cinfo->id, xfer->hdr.protocol_id, + xfer->hdr.id, "NOTI", xfer->hdr.seq, + xfer->hdr.status, xfer->rx.buf, xfer->rx.len); scmi_notify(cinfo->handle, xfer->hdr.protocol_id, xfer->hdr.id, xfer->rx.buf, xfer->rx.len, ts); @@ -678,6 +895,12 @@ static void scmi_handle_notification(struct scmi_chan_info *cinfo, xfer->hdr.protocol_id, xfer->hdr.seq, MSG_TYPE_NOTIFICATION); + if (IS_ENABLED(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT)) { + xfer->hdr.seq = MSG_XTRACT_TOKEN(msg_hdr); + scmi_raw_message_report(info->raw, xfer, SCMI_RAW_NOTIF_QUEUE, + cinfo->id); + } + __scmi_xfer_put(minfo, xfer); scmi_clear_channel(info, cinfo); @@ -691,6 +914,9 @@ static void scmi_handle_response(struct scmi_chan_info *cinfo, xfer = scmi_xfer_command_acquire(cinfo, msg_hdr); if (IS_ERR(xfer)) { + if (IS_ENABLED(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT)) + scmi_raw_error_report(info->raw, cinfo, msg_hdr, priv); + if (MSG_XTRACT_TYPE(msg_hdr) == MSG_TYPE_DELAYED_RESP) scmi_clear_channel(info, cinfo); return; @@ -705,9 +931,11 @@ static void scmi_handle_response(struct scmi_chan_info *cinfo, smp_store_mb(xfer->priv, priv); info->desc->ops->fetch_response(cinfo, xfer); - trace_scmi_msg_dump(xfer->hdr.protocol_id, xfer->hdr.id, + trace_scmi_msg_dump(info->id, cinfo->id, xfer->hdr.protocol_id, + xfer->hdr.id, xfer->hdr.type == MSG_TYPE_DELAYED_RESP ? - "DLYD" : "RESP", + (!SCMI_XFER_IS_RAW(xfer) ? "DLYD" : "dlyd") : + (!SCMI_XFER_IS_RAW(xfer) ? "RESP" : "resp"), xfer->hdr.seq, xfer->hdr.status, xfer->rx.buf, xfer->rx.len); @@ -722,6 +950,18 @@ static void scmi_handle_response(struct scmi_chan_info *cinfo, complete(&xfer->done); } + if (IS_ENABLED(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT)) { + /* + * When in polling mode avoid to queue the Raw xfer on the IRQ + * RX path since it will be already queued at the end of the TX + * poll loop. + */ + if (!xfer->hdr.poll_completion) + scmi_raw_message_report(info->raw, xfer, + SCMI_RAW_REPLY_QUEUE, + cinfo->id); + } + scmi_xfer_command_release(info, xfer); } @@ -785,36 +1025,18 @@ static bool scmi_xfer_done_no_timeout(struct scmi_chan_info *cinfo, ktime_after(ktime_get(), stop); } -/** - * scmi_wait_for_message_response - An helper to group all the possible ways of - * waiting for a synchronous message response. - * - * @cinfo: SCMI channel info - * @xfer: Reference to the transfer being waited for. - * - * Chooses waiting strategy (sleep-waiting vs busy-waiting) depending on - * configuration flags like xfer->hdr.poll_completion. - * - * Return: 0 on Success, error otherwise. - */ -static int scmi_wait_for_message_response(struct scmi_chan_info *cinfo, - struct scmi_xfer *xfer) +static int scmi_wait_for_reply(struct device *dev, const struct scmi_desc *desc, + struct scmi_chan_info *cinfo, + struct scmi_xfer *xfer, unsigned int timeout_ms) { - struct scmi_info *info = handle_to_scmi_info(cinfo->handle); - struct device *dev = info->dev; - int ret = 0, timeout_ms = info->desc->max_rx_timeout_ms; - - trace_scmi_xfer_response_wait(xfer->transfer_id, xfer->hdr.id, - xfer->hdr.protocol_id, xfer->hdr.seq, - timeout_ms, - xfer->hdr.poll_completion); + int ret = 0; if (xfer->hdr.poll_completion) { /* * Real polling is needed only if transport has NOT declared * itself to support synchronous commands replies. */ - if (!info->desc->sync_cmds_completed_on_ret) { + if (!desc->sync_cmds_completed_on_ret) { /* * Poll on xfer using transport provided .poll_done(); * assumes no completion interrupt was available. @@ -833,6 +1055,8 @@ static int scmi_wait_for_message_response(struct scmi_chan_info *cinfo, if (!ret) { unsigned long flags; + struct scmi_info *info = + handle_to_scmi_info(cinfo->handle); /* * Do not fetch_response if an out-of-order delayed @@ -840,16 +1064,27 @@ static int scmi_wait_for_message_response(struct scmi_chan_info *cinfo, */ spin_lock_irqsave(&xfer->lock, flags); if (xfer->state == SCMI_XFER_SENT_OK) { - info->desc->ops->fetch_response(cinfo, xfer); + desc->ops->fetch_response(cinfo, xfer); xfer->state = SCMI_XFER_RESP_OK; } spin_unlock_irqrestore(&xfer->lock, flags); /* Trace polled replies. */ - trace_scmi_msg_dump(xfer->hdr.protocol_id, xfer->hdr.id, - "RESP", + trace_scmi_msg_dump(info->id, cinfo->id, + xfer->hdr.protocol_id, xfer->hdr.id, + !SCMI_XFER_IS_RAW(xfer) ? + "RESP" : "resp", xfer->hdr.seq, xfer->hdr.status, xfer->rx.buf, xfer->rx.len); + + if (IS_ENABLED(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT)) { + struct scmi_info *info = + handle_to_scmi_info(cinfo->handle); + + scmi_raw_message_report(info->raw, xfer, + SCMI_RAW_REPLY_QUEUE, + cinfo->id); + } } } else { /* And we wait for the response. */ @@ -865,6 +1100,59 @@ static int scmi_wait_for_message_response(struct scmi_chan_info *cinfo, } /** + * scmi_wait_for_message_response - An helper to group all the possible ways of + * waiting for a synchronous message response. + * + * @cinfo: SCMI channel info + * @xfer: Reference to the transfer being waited for. + * + * Chooses waiting strategy (sleep-waiting vs busy-waiting) depending on + * configuration flags like xfer->hdr.poll_completion. + * + * Return: 0 on Success, error otherwise. + */ +static int scmi_wait_for_message_response(struct scmi_chan_info *cinfo, + struct scmi_xfer *xfer) +{ + struct scmi_info *info = handle_to_scmi_info(cinfo->handle); + struct device *dev = info->dev; + + trace_scmi_xfer_response_wait(xfer->transfer_id, xfer->hdr.id, + xfer->hdr.protocol_id, xfer->hdr.seq, + info->desc->max_rx_timeout_ms, + xfer->hdr.poll_completion); + + return scmi_wait_for_reply(dev, info->desc, cinfo, xfer, + info->desc->max_rx_timeout_ms); +} + +/** + * scmi_xfer_raw_wait_for_message_response - An helper to wait for a message + * reply to an xfer raw request on a specific channel for the required timeout. + * + * @cinfo: SCMI channel info + * @xfer: Reference to the transfer being waited for. + * @timeout_ms: The maximum timeout in milliseconds + * + * Return: 0 on Success, error otherwise. + */ +int scmi_xfer_raw_wait_for_message_response(struct scmi_chan_info *cinfo, + struct scmi_xfer *xfer, + unsigned int timeout_ms) +{ + int ret; + struct scmi_info *info = handle_to_scmi_info(cinfo->handle); + struct device *dev = info->dev; + + ret = scmi_wait_for_reply(dev, info->desc, cinfo, xfer, timeout_ms); + if (ret) + dev_dbg(dev, "timed out in RAW response - HDR:%08X\n", + pack_scmi_header(&xfer->hdr)); + + return ret; +} + +/** * do_xfer() - Do one transfer * * @ph: Pointer to SCMI protocol handle @@ -884,7 +1172,8 @@ static int do_xfer(const struct scmi_protocol_handle *ph, struct scmi_chan_info *cinfo; /* Check for polling request on custom command xfers at first */ - if (xfer->hdr.poll_completion && !is_transport_polling_capable(info)) { + if (xfer->hdr.poll_completion && + !is_transport_polling_capable(info->desc)) { dev_warn_once(dev, "Polling mode is not supported by transport.\n"); return -EINVAL; @@ -895,7 +1184,7 @@ static int do_xfer(const struct scmi_protocol_handle *ph, return -EINVAL; /* True ONLY if also supported by transport. */ - if (is_polling_enabled(cinfo, info)) + if (is_polling_enabled(cinfo, info->desc)) xfer->hdr.poll_completion = true; /* @@ -928,9 +1217,9 @@ static int do_xfer(const struct scmi_protocol_handle *ph, return ret; } - trace_scmi_msg_dump(xfer->hdr.protocol_id, xfer->hdr.id, "CMND", - xfer->hdr.seq, xfer->hdr.status, - xfer->tx.buf, xfer->tx.len); + trace_scmi_msg_dump(info->id, cinfo->id, xfer->hdr.protocol_id, + xfer->hdr.id, "CMND", xfer->hdr.seq, + xfer->hdr.status, xfer->tx.buf, xfer->tx.len); ret = scmi_wait_for_message_response(cinfo, xfer); if (!ret && xfer->hdr.status) @@ -954,8 +1243,6 @@ static void reset_rx_to_maxsz(const struct scmi_protocol_handle *ph, xfer->rx.len = info->desc->max_msg_size; } -#define SCMI_MAX_RESPONSE_TIMEOUT (2 * MSEC_PER_SEC) - /** * do_xfer_with_response() - Do one transfer and wait until the delayed * response is received @@ -1043,13 +1330,22 @@ static int xfer_get_init(const struct scmi_protocol_handle *ph, tx_size > info->desc->max_msg_size) return -ERANGE; - xfer = scmi_xfer_get(pi->handle, minfo, true); + xfer = scmi_xfer_get(pi->handle, minfo); if (IS_ERR(xfer)) { ret = PTR_ERR(xfer); dev_err(dev, "failed to get free message slot(%d)\n", ret); return ret; } + /* Pick a sequence number and register this xfer as in-flight */ + ret = scmi_xfer_pending_set(xfer, minfo); + if (ret) { + dev_err(pi->handle->dev, + "Failed to get monotonic token %d\n", ret); + __scmi_xfer_put(minfo, xfer); + return ret; + } + xfer->tx.len = tx_size; xfer->rx.len = rx_size ? : info->desc->max_msg_size; xfer->hdr.type = MSG_TYPE_COMMAND; @@ -1822,20 +2118,14 @@ static bool scmi_is_transport_atomic(const struct scmi_handle *handle, bool ret; struct scmi_info *info = handle_to_scmi_info(handle); - ret = info->desc->atomic_enabled && is_transport_polling_capable(info); + ret = info->desc->atomic_enabled && + is_transport_polling_capable(info->desc); if (ret && atomic_threshold) *atomic_threshold = info->atomic_threshold; return ret; } -static inline -struct scmi_handle *scmi_handle_get_from_info_unlocked(struct scmi_info *info) -{ - info->users++; - return &info->handle; -} - /** * scmi_handle_get() - Get the SCMI handle for a device * @@ -1847,7 +2137,7 @@ struct scmi_handle *scmi_handle_get_from_info_unlocked(struct scmi_info *info) * * Return: pointer to handle if successful, NULL on error */ -struct scmi_handle *scmi_handle_get(struct device *dev) +static struct scmi_handle *scmi_handle_get(struct device *dev) { struct list_head *p; struct scmi_info *info; @@ -1857,7 +2147,8 @@ struct scmi_handle *scmi_handle_get(struct device *dev) list_for_each(p, &scmi_list) { info = list_entry(p, struct scmi_info, node); if (dev->parent == info->dev) { - handle = scmi_handle_get_from_info_unlocked(info); + info->users++; + handle = &info->handle; break; } } @@ -1878,7 +2169,7 @@ struct scmi_handle *scmi_handle_get(struct device *dev) * Return: 0 is successfully released * if null was passed, it returns -EINVAL; */ -int scmi_handle_put(const struct scmi_handle *handle) +static int scmi_handle_put(const struct scmi_handle *handle) { struct scmi_info *info; @@ -1894,6 +2185,23 @@ int scmi_handle_put(const struct scmi_handle *handle) return 0; } +static void scmi_device_link_add(struct device *consumer, + struct device *supplier) +{ + struct device_link *link; + + link = device_link_add(consumer, supplier, DL_FLAG_AUTOREMOVE_CONSUMER); + + WARN_ON(!link); +} + +static void scmi_set_handle(struct scmi_device *scmi_dev) +{ + scmi_dev->handle = scmi_handle_get(&scmi_dev->dev); + if (scmi_dev->handle) + scmi_device_link_add(&scmi_dev->dev, scmi_dev->handle->dev); +} + static int __scmi_xfer_info_init(struct scmi_info *sinfo, struct scmi_xfers_info *info) { @@ -1987,23 +2295,20 @@ static int scmi_xfer_info_init(struct scmi_info *sinfo) return ret; } -static int scmi_chan_setup(struct scmi_info *info, struct device *dev, +static int scmi_chan_setup(struct scmi_info *info, struct device_node *of_node, int prot_id, bool tx) { int ret, idx; + char name[32]; struct scmi_chan_info *cinfo; struct idr *idr; + struct scmi_device *tdev = NULL; /* Transmit channel is first entry i.e. index 0 */ idx = tx ? 0 : 1; idr = tx ? &info->tx_idr : &info->rx_idr; - /* check if already allocated, used for multiple device per protocol */ - cinfo = idr_find(idr, prot_id); - if (cinfo) - return 0; - - if (!info->desc->ops->chan_available(dev, idx)) { + if (!info->desc->ops->chan_available(of_node, idx)) { cinfo = idr_find(idr, SCMI_PROTOCOL_BASE); if (unlikely(!cinfo)) /* Possible only if platform has no Rx */ return -EINVAL; @@ -2014,27 +2319,52 @@ static int scmi_chan_setup(struct scmi_info *info, struct device *dev, if (!cinfo) return -ENOMEM; - cinfo->dev = dev; cinfo->rx_timeout_ms = info->desc->max_rx_timeout_ms; + /* Create a unique name for this transport device */ + snprintf(name, 32, "__scmi_transport_device_%s_%02X", + idx ? "rx" : "tx", prot_id); + /* Create a uniquely named, dedicated transport device for this chan */ + tdev = scmi_device_create(of_node, info->dev, prot_id, name); + if (!tdev) { + dev_err(info->dev, + "failed to create transport device (%s)\n", name); + devm_kfree(info->dev, cinfo); + return -EINVAL; + } + of_node_get(of_node); + + cinfo->id = prot_id; + cinfo->dev = &tdev->dev; ret = info->desc->ops->chan_setup(cinfo, info->dev, tx); - if (ret) + if (ret) { + of_node_put(of_node); + scmi_device_destroy(info->dev, prot_id, name); + devm_kfree(info->dev, cinfo); return ret; + } - if (tx && is_polling_required(cinfo, info)) { - if (is_transport_polling_capable(info)) - dev_info(dev, + if (tx && is_polling_required(cinfo, info->desc)) { + if (is_transport_polling_capable(info->desc)) + dev_info(&tdev->dev, "Enabled polling mode TX channel - prot_id:%d\n", prot_id); else - dev_warn(dev, + dev_warn(&tdev->dev, "Polling mode NOT supported by transport.\n"); } idr_alloc: ret = idr_alloc(idr, cinfo, prot_id, prot_id + 1, GFP_KERNEL); if (ret != prot_id) { - dev_err(dev, "unable to allocate SCMI idr slot err %d\n", ret); + dev_err(info->dev, + "unable to allocate SCMI idr slot err %d\n", ret); + /* Destroy channel and device only if created by this call. */ + if (tdev) { + of_node_put(of_node); + scmi_device_destroy(info->dev, prot_id, name); + devm_kfree(info->dev, cinfo); + } return ret; } @@ -2043,13 +2373,14 @@ idr_alloc: } static inline int -scmi_txrx_setup(struct scmi_info *info, struct device *dev, int prot_id) +scmi_txrx_setup(struct scmi_info *info, struct device_node *of_node, + int prot_id) { - int ret = scmi_chan_setup(info, dev, prot_id, true); + int ret = scmi_chan_setup(info, of_node, prot_id, true); if (!ret) { /* Rx is optional, report only memory errors */ - ret = scmi_chan_setup(info, dev, prot_id, false); + ret = scmi_chan_setup(info, of_node, prot_id, false); if (ret && ret != -ENOMEM) ret = 0; } @@ -2058,306 +2389,264 @@ scmi_txrx_setup(struct scmi_info *info, struct device *dev, int prot_id) } /** - * scmi_get_protocol_device - Helper to get/create an SCMI device. - * - * @np: A device node representing a valid active protocols for the referred - * SCMI instance. - * @info: The referred SCMI instance for which we are getting/creating this - * device. - * @prot_id: The protocol ID. - * @name: The device name. - * - * Referring to the specific SCMI instance identified by @info, this helper - * takes care to return a properly initialized device matching the requested - * @proto_id and @name: if device was still not existent it is created as a - * child of the specified SCMI instance @info and its transport properly - * initialized as usual. - * - * Return: A properly initialized scmi device, NULL otherwise. + * scmi_channels_setup - Helper to initialize all required channels + * + * @info: The SCMI instance descriptor. + * + * Initialize all the channels found described in the DT against the underlying + * configured transport using custom defined dedicated devices instead of + * borrowing devices from the SCMI drivers; this way channels are initialized + * upfront during core SCMI stack probing and are no more coupled with SCMI + * devices used by SCMI drivers. + * + * Note that, even though a pair of TX/RX channels is associated to each + * protocol defined in the DT, a distinct freshly initialized channel is + * created only if the DT node for the protocol at hand describes a dedicated + * channel: in all the other cases the common BASE protocol channel is reused. + * + * Return: 0 on Success */ -static inline struct scmi_device * -scmi_get_protocol_device(struct device_node *np, struct scmi_info *info, - int prot_id, const char *name) +static int scmi_channels_setup(struct scmi_info *info) { - struct scmi_device *sdev; + int ret; + struct device_node *child, *top_np = info->dev->of_node; - /* Already created for this parent SCMI instance ? */ - sdev = scmi_child_dev_find(info->dev, prot_id, name); - if (sdev) - return sdev; + /* Initialize a common generic channel at first */ + ret = scmi_txrx_setup(info, top_np, SCMI_PROTOCOL_BASE); + if (ret) + return ret; - mutex_lock(&scmi_syspower_mtx); - if (prot_id == SCMI_PROTOCOL_SYSTEM && scmi_syspower_registered) { - dev_warn(info->dev, - "SCMI SystemPower protocol device must be unique !\n"); - mutex_unlock(&scmi_syspower_mtx); + for_each_available_child_of_node(top_np, child) { + u32 prot_id; - return NULL; + if (of_property_read_u32(child, "reg", &prot_id)) + continue; + + if (!FIELD_FIT(MSG_PROTOCOL_ID_MASK, prot_id)) + dev_err(info->dev, + "Out of range protocol %d\n", prot_id); + + ret = scmi_txrx_setup(info, child, prot_id); + if (ret) { + of_node_put(child); + return ret; + } } - pr_debug("Creating SCMI device (%s) for protocol %x\n", name, prot_id); + return 0; +} - sdev = scmi_device_create(np, info->dev, prot_id, name); - if (!sdev) { - dev_err(info->dev, "failed to create %d protocol device\n", - prot_id); - mutex_unlock(&scmi_syspower_mtx); +static int scmi_chan_destroy(int id, void *p, void *idr) +{ + struct scmi_chan_info *cinfo = p; - return NULL; + if (cinfo->dev) { + struct scmi_info *info = handle_to_scmi_info(cinfo->handle); + struct scmi_device *sdev = to_scmi_dev(cinfo->dev); + + of_node_put(cinfo->dev->of_node); + scmi_device_destroy(info->dev, id, sdev->name); + cinfo->dev = NULL; } - if (scmi_txrx_setup(info, &sdev->dev, prot_id)) { - dev_err(&sdev->dev, "failed to setup transport\n"); - scmi_device_destroy(sdev); - mutex_unlock(&scmi_syspower_mtx); + idr_remove(idr, id); - return NULL; - } + return 0; +} - if (prot_id == SCMI_PROTOCOL_SYSTEM) - scmi_syspower_registered = true; +static void scmi_cleanup_channels(struct scmi_info *info, struct idr *idr) +{ + /* At first free all channels at the transport layer ... */ + idr_for_each(idr, info->desc->ops->chan_free, idr); - mutex_unlock(&scmi_syspower_mtx); + /* ...then destroy all underlying devices */ + idr_for_each(idr, scmi_chan_destroy, idr); - return sdev; + idr_destroy(idr); } -static inline void -scmi_create_protocol_device(struct device_node *np, struct scmi_info *info, - int prot_id, const char *name) +static void scmi_cleanup_txrx_channels(struct scmi_info *info) { - struct scmi_device *sdev; - - sdev = scmi_get_protocol_device(np, info, prot_id, name); - if (!sdev) - return; + scmi_cleanup_channels(info, &info->tx_idr); - /* setup handle now as the transport is ready */ - scmi_set_handle(sdev); + scmi_cleanup_channels(info, &info->rx_idr); } -/** - * scmi_create_protocol_devices - Create devices for all pending requests for - * this SCMI instance. - * - * @np: The device node describing the protocol - * @info: The SCMI instance descriptor - * @prot_id: The protocol ID - * - * All devices previously requested for this instance (if any) are found and - * created by scanning the proper @&scmi_requested_devices entry. - */ -static void scmi_create_protocol_devices(struct device_node *np, - struct scmi_info *info, int prot_id) +static int scmi_bus_notifier(struct notifier_block *nb, + unsigned long action, void *data) { - struct list_head *phead; + struct scmi_info *info = bus_nb_to_scmi_info(nb); + struct scmi_device *sdev = to_scmi_dev(data); - mutex_lock(&scmi_requested_devices_mtx); - phead = idr_find(&scmi_requested_devices, prot_id); - if (phead) { - struct scmi_requested_dev *rdev; + /* Skip transport devices and devices of different SCMI instances */ + if (!strncmp(sdev->name, "__scmi_transport_device", 23) || + sdev->dev.parent != info->dev) + return NOTIFY_DONE; - list_for_each_entry(rdev, phead, node) - scmi_create_protocol_device(np, info, prot_id, - rdev->id_table->name); + switch (action) { + case BUS_NOTIFY_BIND_DRIVER: + /* setup handle now as the transport is ready */ + scmi_set_handle(sdev); + break; + case BUS_NOTIFY_UNBOUND_DRIVER: + scmi_handle_put(sdev->handle); + sdev->handle = NULL; + break; + default: + return NOTIFY_DONE; } - mutex_unlock(&scmi_requested_devices_mtx); + + dev_dbg(info->dev, "Device %s (%s) is now %s\n", dev_name(&sdev->dev), + sdev->name, action == BUS_NOTIFY_BIND_DRIVER ? + "about to be BOUND." : "UNBOUND."); + + return NOTIFY_OK; } -/** - * scmi_protocol_device_request - Helper to request a device - * - * @id_table: A protocol/name pair descriptor for the device to be created. - * - * This helper let an SCMI driver request specific devices identified by the - * @id_table to be created for each active SCMI instance. - * - * The requested device name MUST NOT be already existent for any protocol; - * at first the freshly requested @id_table is annotated in the IDR table - * @scmi_requested_devices, then a matching device is created for each already - * active SCMI instance. (if any) - * - * This way the requested device is created straight-away for all the already - * initialized(probed) SCMI instances (handles) and it remains also annotated - * as pending creation if the requesting SCMI driver was loaded before some - * SCMI instance and related transports were available: when such late instance - * is probed, its probe will take care to scan the list of pending requested - * devices and create those on its own (see @scmi_create_protocol_devices and - * its enclosing loop) - * - * Return: 0 on Success - */ -int scmi_protocol_device_request(const struct scmi_device_id *id_table) +static int scmi_device_request_notifier(struct notifier_block *nb, + unsigned long action, void *data) { - int ret = 0; - unsigned int id = 0; - struct list_head *head, *phead = NULL; - struct scmi_requested_dev *rdev; - struct scmi_info *info; + struct device_node *np; + struct scmi_device_id *id_table = data; + struct scmi_info *info = req_nb_to_scmi_info(nb); - pr_debug("Requesting SCMI device (%s) for protocol %x\n", - id_table->name, id_table->protocol_id); + np = idr_find(&info->active_protocols, id_table->protocol_id); + if (!np) + return NOTIFY_DONE; - /* - * Search for the matching protocol rdev list and then search - * of any existent equally named device...fails if any duplicate found. - */ - mutex_lock(&scmi_requested_devices_mtx); - idr_for_each_entry(&scmi_requested_devices, head, id) { - if (!phead) { - /* A list found registered in the IDR is never empty */ - rdev = list_first_entry(head, struct scmi_requested_dev, - node); - if (rdev->id_table->protocol_id == - id_table->protocol_id) - phead = head; - } - list_for_each_entry(rdev, head, node) { - if (!strcmp(rdev->id_table->name, id_table->name)) { - pr_err("Ignoring duplicate request [%d] %s\n", - rdev->id_table->protocol_id, - rdev->id_table->name); - ret = -EINVAL; - goto out; - } - } - } + dev_dbg(info->dev, "%sRequested device (%s) for protocol 0x%x\n", + action == SCMI_BUS_NOTIFY_DEVICE_REQUEST ? "" : "UN-", + id_table->name, id_table->protocol_id); - /* - * No duplicate found for requested id_table, so let's create a new - * requested device entry for this new valid request. - */ - rdev = kzalloc(sizeof(*rdev), GFP_KERNEL); - if (!rdev) { - ret = -ENOMEM; - goto out; + switch (action) { + case SCMI_BUS_NOTIFY_DEVICE_REQUEST: + scmi_create_protocol_devices(np, info, id_table->protocol_id, + id_table->name); + break; + case SCMI_BUS_NOTIFY_DEVICE_UNREQUEST: + scmi_destroy_protocol_devices(info, id_table->protocol_id, + id_table->name); + break; + default: + return NOTIFY_DONE; } - rdev->id_table = id_table; - /* - * Append the new requested device table descriptor to the head of the - * related protocol list, eventually creating such head if not already - * there. - */ - if (!phead) { - phead = kzalloc(sizeof(*phead), GFP_KERNEL); - if (!phead) { - kfree(rdev); - ret = -ENOMEM; - goto out; - } - INIT_LIST_HEAD(phead); - - ret = idr_alloc(&scmi_requested_devices, (void *)phead, - id_table->protocol_id, - id_table->protocol_id + 1, GFP_KERNEL); - if (ret != id_table->protocol_id) { - pr_err("Failed to save SCMI device - ret:%d\n", ret); - kfree(rdev); - kfree(phead); - ret = -EINVAL; - goto out; - } - ret = 0; - } - list_add(&rdev->node, phead); + return NOTIFY_OK; +} - /* - * Now effectively create and initialize the requested device for every - * already initialized SCMI instance which has registered the requested - * protocol as a valid active one: i.e. defined in DT and supported by - * current platform FW. - */ - mutex_lock(&scmi_list_mutex); - list_for_each_entry(info, &scmi_list, node) { - struct device_node *child; - - child = idr_find(&info->active_protocols, - id_table->protocol_id); - if (child) { - struct scmi_device *sdev; - - sdev = scmi_get_protocol_device(child, info, - id_table->protocol_id, - id_table->name); - if (sdev) { - /* Set handle if not already set: device existed */ - if (!sdev->handle) - sdev->handle = - scmi_handle_get_from_info_unlocked(info); - /* Relink consumer and suppliers */ - if (sdev->handle) - scmi_device_link_add(&sdev->dev, - sdev->handle->dev); - } - } else { - dev_err(info->dev, - "Failed. SCMI protocol %d not active.\n", - id_table->protocol_id); - } - } - mutex_unlock(&scmi_list_mutex); +static void scmi_debugfs_common_cleanup(void *d) +{ + struct scmi_debug_info *dbg = d; -out: - mutex_unlock(&scmi_requested_devices_mtx); + if (!dbg) + return; - return ret; + debugfs_remove_recursive(dbg->top_dentry); + kfree(dbg->name); + kfree(dbg->type); } -/** - * scmi_protocol_device_unrequest - Helper to unrequest a device - * - * @id_table: A protocol/name pair descriptor for the device to be unrequested. - * - * An helper to let an SCMI driver release its request about devices; note that - * devices are created and initialized once the first SCMI driver request them - * but they destroyed only on SCMI core unloading/unbinding. - * - * The current SCMI transport layer uses such devices as internal references and - * as such they could be shared as same transport between multiple drivers so - * that cannot be safely destroyed till the whole SCMI stack is removed. - * (unless adding further burden of refcounting.) - */ -void scmi_protocol_device_unrequest(const struct scmi_device_id *id_table) +static struct scmi_debug_info *scmi_debugfs_common_setup(struct scmi_info *info) { - struct list_head *phead; + char top_dir[16]; + struct dentry *trans, *top_dentry; + struct scmi_debug_info *dbg; + const char *c_ptr = NULL; - pr_debug("Unrequesting SCMI device (%s) for protocol %x\n", - id_table->name, id_table->protocol_id); + dbg = devm_kzalloc(info->dev, sizeof(*dbg), GFP_KERNEL); + if (!dbg) + return NULL; - mutex_lock(&scmi_requested_devices_mtx); - phead = idr_find(&scmi_requested_devices, id_table->protocol_id); - if (phead) { - struct scmi_requested_dev *victim, *tmp; + dbg->name = kstrdup(of_node_full_name(info->dev->of_node), GFP_KERNEL); + if (!dbg->name) { + devm_kfree(info->dev, dbg); + return NULL; + } - list_for_each_entry_safe(victim, tmp, phead, node) { - if (!strcmp(victim->id_table->name, id_table->name)) { - list_del(&victim->node); - kfree(victim); - break; - } - } + of_property_read_string(info->dev->of_node, "compatible", &c_ptr); + dbg->type = kstrdup(c_ptr, GFP_KERNEL); + if (!dbg->type) { + kfree(dbg->name); + devm_kfree(info->dev, dbg); + return NULL; + } - if (list_empty(phead)) { - idr_remove(&scmi_requested_devices, - id_table->protocol_id); - kfree(phead); - } + snprintf(top_dir, 16, "%d", info->id); + top_dentry = debugfs_create_dir(top_dir, scmi_top_dentry); + trans = debugfs_create_dir("transport", top_dentry); + + dbg->is_atomic = info->desc->atomic_enabled && + is_transport_polling_capable(info->desc); + + debugfs_create_str("instance_name", 0400, top_dentry, + (char **)&dbg->name); + + debugfs_create_u32("atomic_threshold_us", 0400, top_dentry, + &info->atomic_threshold); + + debugfs_create_str("type", 0400, trans, (char **)&dbg->type); + + debugfs_create_bool("is_atomic", 0400, trans, &dbg->is_atomic); + + debugfs_create_u32("max_rx_timeout_ms", 0400, trans, + (u32 *)&info->desc->max_rx_timeout_ms); + + debugfs_create_u32("max_msg_size", 0400, trans, + (u32 *)&info->desc->max_msg_size); + + debugfs_create_u32("tx_max_msg", 0400, trans, + (u32 *)&info->tx_minfo.max_msg); + + debugfs_create_u32("rx_max_msg", 0400, trans, + (u32 *)&info->rx_minfo.max_msg); + + dbg->top_dentry = top_dentry; + + if (devm_add_action_or_reset(info->dev, + scmi_debugfs_common_cleanup, dbg)) { + scmi_debugfs_common_cleanup(dbg); + return NULL; } - mutex_unlock(&scmi_requested_devices_mtx); + + return dbg; } -static int scmi_cleanup_txrx_channels(struct scmi_info *info) +static int scmi_debugfs_raw_mode_setup(struct scmi_info *info) { - int ret; - struct idr *idr = &info->tx_idr; + int id, num_chans = 0, ret = 0; + struct scmi_chan_info *cinfo; + u8 channels[SCMI_MAX_CHANNELS] = {}; + DECLARE_BITMAP(protos, SCMI_MAX_CHANNELS) = {}; + + if (!info->dbg) + return -EINVAL; + + /* Enumerate all channels to collect their ids */ + idr_for_each_entry(&info->tx_idr, cinfo, id) { + /* + * Cannot happen, but be defensive. + * Zero as num_chans is ok, warn and carry on. + */ + if (num_chans >= SCMI_MAX_CHANNELS || !cinfo) { + dev_warn(info->dev, + "SCMI RAW - Error enumerating channels\n"); + break; + } - ret = idr_for_each(idr, info->desc->ops->chan_free, idr); - idr_destroy(&info->tx_idr); + if (!test_bit(cinfo->id, protos)) { + channels[num_chans++] = cinfo->id; + set_bit(cinfo->id, protos); + } + } - idr = &info->rx_idr; - ret = idr_for_each(idr, info->desc->ops->chan_free, idr); - idr_destroy(&info->rx_idr); + info->raw = scmi_raw_mode_init(&info->handle, info->dbg->top_dentry, + info->id, channels, num_chans, + info->desc, info->tx_minfo.max_msg); + if (IS_ERR(info->raw)) { + dev_err(info->dev, "Failed to initialize SCMI RAW Mode !\n"); + ret = PTR_ERR(info->raw); + info->raw = NULL; + } return ret; } @@ -2379,12 +2668,19 @@ static int scmi_probe(struct platform_device *pdev) if (!info) return -ENOMEM; + info->id = ida_alloc_min(&scmi_id, 0, GFP_KERNEL); + if (info->id < 0) + return info->id; + info->dev = dev; info->desc = desc; + info->bus_nb.notifier_call = scmi_bus_notifier; + info->dev_req_nb.notifier_call = scmi_device_request_notifier; INIT_LIST_HEAD(&info->node); idr_init(&info->protocols); mutex_init(&info->protocols_mtx); idr_init(&info->active_protocols); + mutex_init(&info->devreq_mtx); platform_set_drvdata(pdev, info); idr_init(&info->tx_idr); @@ -2408,21 +2704,55 @@ static int scmi_probe(struct platform_device *pdev) if (desc->ops->link_supplier) { ret = desc->ops->link_supplier(dev); if (ret) - return ret; + goto clear_ida; } - ret = scmi_txrx_setup(info, dev, SCMI_PROTOCOL_BASE); + /* Setup all channels described in the DT at first */ + ret = scmi_channels_setup(info); if (ret) - return ret; + goto clear_ida; - ret = scmi_xfer_info_init(info); + ret = bus_register_notifier(&scmi_bus_type, &info->bus_nb); if (ret) goto clear_txrx_setup; + ret = blocking_notifier_chain_register(&scmi_requested_devices_nh, + &info->dev_req_nb); + if (ret) + goto clear_bus_notifier; + + ret = scmi_xfer_info_init(info); + if (ret) + goto clear_dev_req_notifier; + + if (scmi_top_dentry) { + info->dbg = scmi_debugfs_common_setup(info); + if (!info->dbg) + dev_warn(dev, "Failed to setup SCMI debugfs.\n"); + + if (IS_ENABLED(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT)) { + bool coex = + IS_ENABLED(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT_COEX); + + ret = scmi_debugfs_raw_mode_setup(info); + if (!coex) { + if (ret) + goto clear_dev_req_notifier; + + /* Bail out anyway when coex enabled */ + return ret; + } + + /* Coex enabled, carry on in any case. */ + dev_info(dev, "SCMI RAW Mode COEX enabled !\n"); + } + } + if (scmi_notification_init(handle)) dev_err(dev, "SCMI Notifications NOT available.\n"); - if (info->desc->atomic_enabled && !is_transport_polling_capable(info)) + if (info->desc->atomic_enabled && + !is_transport_polling_capable(info->desc)) dev_err(dev, "Transport is not polling capable. Atomic mode not supported.\n"); @@ -2469,29 +2799,36 @@ static int scmi_probe(struct platform_device *pdev) } of_node_get(child); - scmi_create_protocol_devices(child, info, prot_id); + scmi_create_protocol_devices(child, info, prot_id, NULL); } return 0; notification_exit: + if (IS_ENABLED(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT)) + scmi_raw_mode_cleanup(info->raw); scmi_notification_exit(&info->handle); +clear_dev_req_notifier: + blocking_notifier_chain_unregister(&scmi_requested_devices_nh, + &info->dev_req_nb); +clear_bus_notifier: + bus_unregister_notifier(&scmi_bus_type, &info->bus_nb); clear_txrx_setup: scmi_cleanup_txrx_channels(info); +clear_ida: + ida_free(&scmi_id, info->id); return ret; } -void scmi_free_channel(struct scmi_chan_info *cinfo, struct idr *idr, int id) -{ - idr_remove(idr, id); -} - static int scmi_remove(struct platform_device *pdev) { - int ret, id; + int id; struct scmi_info *info = platform_get_drvdata(pdev); struct device_node *child; + if (IS_ENABLED(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT)) + scmi_raw_mode_cleanup(info->raw); + mutex_lock(&scmi_list_mutex); if (info->users) dev_warn(&pdev->dev, @@ -2509,10 +2846,14 @@ static int scmi_remove(struct platform_device *pdev) of_node_put(child); idr_destroy(&info->active_protocols); + blocking_notifier_chain_unregister(&scmi_requested_devices_nh, + &info->dev_req_nb); + bus_unregister_notifier(&scmi_bus_type, &info->bus_nb); + /* Safe to free channels since no more users */ - ret = scmi_cleanup_txrx_channels(info); - if (ret) - dev_warn(&pdev->dev, "Failed to cleanup SCMI channels.\n"); + scmi_cleanup_txrx_channels(info); + + ida_free(&scmi_id, info->id); return 0; } @@ -2641,6 +2982,19 @@ static void __exit scmi_transports_exit(void) __scmi_transports_setup(false); } +static struct dentry *scmi_debugfs_init(void) +{ + struct dentry *d; + + d = debugfs_create_dir("scmi", NULL); + if (IS_ERR(d)) { + pr_err("Could NOT create SCMI top dentry.\n"); + return NULL; + } + + return d; +} + static int __init scmi_driver_init(void) { int ret; @@ -2649,13 +3003,14 @@ static int __init scmi_driver_init(void) if (WARN_ON(!IS_ENABLED(CONFIG_ARM_SCMI_HAVE_TRANSPORT))) return -EINVAL; - scmi_bus_init(); - /* Initialize any compiled-in transport which provided an init/exit */ ret = scmi_transports_init(); if (ret) return ret; + if (IS_ENABLED(CONFIG_ARM_SCMI_NEED_DEBUGFS)) + scmi_top_dentry = scmi_debugfs_init(); + scmi_base_register(); scmi_clock_register(); @@ -2669,7 +3024,7 @@ static int __init scmi_driver_init(void) return platform_driver_register(&scmi_driver); } -subsys_initcall(scmi_driver_init); +module_init(scmi_driver_init); static void __exit scmi_driver_exit(void) { @@ -2684,11 +3039,11 @@ static void __exit scmi_driver_exit(void) scmi_system_unregister(); scmi_powercap_unregister(); - scmi_bus_exit(); - scmi_transports_exit(); platform_driver_unregister(&scmi_driver); + + debugfs_remove_recursive(scmi_top_dentry); } module_exit(scmi_driver_exit); diff --git a/drivers/firmware/arm_scmi/mailbox.c b/drivers/firmware/arm_scmi/mailbox.c index 1e40cb035044..0d9c9538b7f4 100644 --- a/drivers/firmware/arm_scmi/mailbox.c +++ b/drivers/firmware/arm_scmi/mailbox.c @@ -46,9 +46,9 @@ static void rx_callback(struct mbox_client *cl, void *m) scmi_rx_callback(smbox->cinfo, shmem_read_header(smbox->shmem), NULL); } -static bool mailbox_chan_available(struct device *dev, int idx) +static bool mailbox_chan_available(struct device_node *of_node, int idx) { - return !of_parse_phandle_with_args(dev->of_node, "mboxes", + return !of_parse_phandle_with_args(of_node, "mboxes", "#mbox-cells", idx, NULL); } @@ -120,8 +120,6 @@ static int mailbox_chan_free(int id, void *p, void *data) smbox->cinfo = NULL; } - scmi_free_channel(cinfo, data, id); - return 0; } diff --git a/drivers/firmware/arm_scmi/optee.c b/drivers/firmware/arm_scmi/optee.c index 2a7aeab40e54..929720387102 100644 --- a/drivers/firmware/arm_scmi/optee.c +++ b/drivers/firmware/arm_scmi/optee.c @@ -328,11 +328,11 @@ static int scmi_optee_link_supplier(struct device *dev) return 0; } -static bool scmi_optee_chan_available(struct device *dev, int idx) +static bool scmi_optee_chan_available(struct device_node *of_node, int idx) { u32 channel_id; - return !of_property_read_u32_index(dev->of_node, "linaro,optee-channel-id", + return !of_property_read_u32_index(of_node, "linaro,optee-channel-id", idx, &channel_id); } @@ -481,8 +481,6 @@ static int scmi_optee_chan_free(int id, void *p, void *data) cinfo->transport_info = NULL; channel->cinfo = NULL; - scmi_free_channel(cinfo, data, id); - return 0; } diff --git a/drivers/firmware/arm_scmi/protocols.h b/drivers/firmware/arm_scmi/protocols.h index 2f3bf691db7c..78e1a01eb656 100644 --- a/drivers/firmware/arm_scmi/protocols.h +++ b/drivers/firmware/arm_scmi/protocols.h @@ -115,6 +115,7 @@ struct scmi_msg_hdr { * - SCMI_XFER_SENT_OK -> SCMI_XFER_RESP_OK [ -> SCMI_XFER_DRESP_OK ] * - SCMI_XFER_SENT_OK -> SCMI_XFER_DRESP_OK * (Missing synchronous response is assumed OK and ignored) + * @flags: Optional flags associated to this xfer. * @lock: A spinlock to protect state and busy fields. * @priv: A pointer for transport private usage. */ @@ -135,6 +136,12 @@ struct scmi_xfer { #define SCMI_XFER_RESP_OK 1 #define SCMI_XFER_DRESP_OK 2 int state; +#define SCMI_XFER_FLAG_IS_RAW BIT(0) +#define SCMI_XFER_IS_RAW(x) ((x)->flags & SCMI_XFER_FLAG_IS_RAW) +#define SCMI_XFER_FLAG_CHAN_SET BIT(1) +#define SCMI_XFER_IS_CHAN_SET(x) \ + ((x)->flags & SCMI_XFER_FLAG_CHAN_SET) + int flags; /* A lock to protect state and busy fields */ spinlock_t lock; void *priv; diff --git a/drivers/firmware/arm_scmi/raw_mode.c b/drivers/firmware/arm_scmi/raw_mode.c new file mode 100644 index 000000000000..d40df099fd51 --- /dev/null +++ b/drivers/firmware/arm_scmi/raw_mode.c @@ -0,0 +1,1443 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * System Control and Management Interface (SCMI) Raw mode support + * + * Copyright (C) 2022 ARM Ltd. + */ +/** + * DOC: Theory of operation + * + * When enabled the SCMI Raw mode support exposes a userspace API which allows + * to send and receive SCMI commands, replies and notifications from a user + * application through injection and snooping of bare SCMI messages in binary + * little-endian format. + * + * Such injected SCMI transactions will then be routed through the SCMI core + * stack towards the SCMI backend server using whatever SCMI transport is + * currently configured on the system under test. + * + * It is meant to help in running any sort of SCMI backend server testing, no + * matter where the server is placed, as long as it is normally reachable via + * the transport configured on the system. + * + * It is activated by a Kernel configuration option since it is NOT meant to + * be used in production but only during development and in CI deployments. + * + * In order to avoid possible interferences between the SCMI Raw transactions + * originated from a test-suite and the normal operations of the SCMI drivers, + * when Raw mode is enabled, by default, all the regular SCMI drivers are + * inhibited, unless CONFIG_ARM_SCMI_RAW_MODE_SUPPORT_COEX is enabled: in this + * latter case the regular SCMI stack drivers will be loaded as usual and it is + * up to the user of this interface to take care of manually inhibiting the + * regular SCMI drivers in order to avoid interferences during the test runs. + * + * The exposed API is as follows. + * + * All SCMI Raw entries are rooted under a common top /raw debugfs top directory + * which in turn is rooted under the corresponding underlying SCMI instance. + * + * /sys/kernel/debug/scmi/ + * `-- 0 + * |-- atomic_threshold_us + * |-- instance_name + * |-- raw + * | |-- channels + * | | |-- 0x10 + * | | | |-- message + * | | | `-- message_async + * | | `-- 0x13 + * | | |-- message + * | | `-- message_async + * | |-- errors + * | |-- message + * | |-- message_async + * | |-- notification + * | `-- reset + * `-- transport + * |-- is_atomic + * |-- max_msg_size + * |-- max_rx_timeout_ms + * |-- rx_max_msg + * |-- tx_max_msg + * `-- type + * + * where: + * + * - errors: used to read back timed-out and unexpected replies + * - message*: used to send sync/async commands and read back immediate and + * delayed reponses (if any) + * - notification: used to read any notification being emitted by the system + * (if previously enabled by the user app) + * - reset: used to flush the queues of messages (of any kind) still pending + * to be read; this is useful at test-suite start/stop to get + * rid of any unread messages from the previous run. + * + * with the per-channel entries rooted at /channels being present only on a + * system where multiple transport channels have been configured. + * + * Such per-channel entries can be used to explicitly choose a specific channel + * for SCMI bare message injection, in contrast with the general entries above + * where, instead, the selection of the proper channel to use is automatically + * performed based the protocol embedded in the injected message and on how the + * transport is configured on the system. + * + * Note that other common general entries are available under transport/ to let + * the user applications properly make up their expectations in terms of + * timeouts and message characteristics. + * + * Each write to the message* entries causes one command request to be built + * and sent while the replies or delayed response are read back from those same + * entries one message at time (receiving an EOF at each message boundary). + * + * The user application running the test is in charge of handling timeouts + * on replies and properly choosing SCMI sequence numbers for the outgoing + * requests (using the same sequence number is supported but discouraged). + * + * Injection of multiple in-flight requests is supported as long as the user + * application uses properly distinct sequence numbers for concurrent requests + * and takes care to properly manage all the related issues about concurrency + * and command/reply pairing. Keep in mind that, anyway, the real level of + * parallelism attainable in such scenario is dependent on the characteristics + * of the underlying transport being used. + * + * Since the SCMI core regular stack is partially used to deliver and collect + * the messages, late replies arrived after timeouts and any other sort of + * unexpected message can be identified by the SCMI core as usual and they will + * be reported as messages under "errors" for later analysis. + */ + +#include <linux/bitmap.h> +#include <linux/debugfs.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/export.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/fs.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/poll.h> +#include <linux/of.h> +#include <linux/slab.h> +#include <linux/xarray.h> + +#include "common.h" + +#include "raw_mode.h" + +#include <trace/events/scmi.h> + +#define SCMI_XFER_RAW_MAX_RETRIES 10 + +/** + * struct scmi_raw_queue - Generic Raw queue descriptor + * + * @free_bufs: A freelists listhead used to keep unused raw buffers + * @free_bufs_lock: Spinlock used to protect access to @free_bufs + * @msg_q: A listhead to a queue of snooped messages waiting to be read out + * @msg_q_lock: Spinlock used to protect access to @msg_q + * @wq: A waitqueue used to wait and poll on related @msg_q + */ +struct scmi_raw_queue { + struct list_head free_bufs; + /* Protect free_bufs[] lists */ + spinlock_t free_bufs_lock; + struct list_head msg_q; + /* Protect msg_q[] lists */ + spinlock_t msg_q_lock; + wait_queue_head_t wq; +}; + +/** + * struct scmi_raw_mode_info - Structure holding SCMI Raw instance data + * + * @id: Sequential Raw instance ID. + * @handle: Pointer to SCMI entity handle to use + * @desc: Pointer to the transport descriptor to use + * @tx_max_msg: Maximum number of concurrent TX in-flight messages + * @q: An array of Raw queue descriptors + * @chans_q: An XArray mapping optional additional per-channel queues + * @free_waiters: Head of freelist for unused waiters + * @free_mtx: A mutex to protect the waiters freelist + * @active_waiters: Head of list for currently active and used waiters + * @active_mtx: A mutex to protect the active waiters list + * @waiters_work: A work descriptor to be used with the workqueue machinery + * @wait_wq: A workqueue reference to the created workqueue + * @dentry: Top debugfs root dentry for SCMI Raw + * @gid: A group ID used for devres accounting + * + * Note that this descriptor is passed back to the core after SCMI Raw is + * initialized as an opaque handle to use by subsequent SCMI Raw call hooks. + * + */ +struct scmi_raw_mode_info { + unsigned int id; + const struct scmi_handle *handle; + const struct scmi_desc *desc; + int tx_max_msg; + struct scmi_raw_queue *q[SCMI_RAW_MAX_QUEUE]; + struct xarray chans_q; + struct list_head free_waiters; + /* Protect free_waiters list */ + struct mutex free_mtx; + struct list_head active_waiters; + /* Protect active_waiters list */ + struct mutex active_mtx; + struct work_struct waiters_work; + struct workqueue_struct *wait_wq; + struct dentry *dentry; + void *gid; +}; + +/** + * struct scmi_xfer_raw_waiter - Structure to describe an xfer to be waited for + * + * @start_jiffies: The timestamp in jiffies of when this structure was queued. + * @cinfo: A reference to the channel to use for this transaction + * @xfer: A reference to the xfer to be waited for + * @async_response: A completion to be, optionally, used for async waits: it + * will be setup by @scmi_do_xfer_raw_start, if needed, to be + * pointed at by xfer->async_done. + * @node: A list node. + */ +struct scmi_xfer_raw_waiter { + unsigned long start_jiffies; + struct scmi_chan_info *cinfo; + struct scmi_xfer *xfer; + struct completion async_response; + struct list_head node; +}; + +/** + * struct scmi_raw_buffer - Structure to hold a full SCMI message + * + * @max_len: The maximum allowed message size (header included) that can be + * stored into @msg + * @msg: A message buffer used to collect a full message grabbed from an xfer. + * @node: A list node. + */ +struct scmi_raw_buffer { + size_t max_len; + struct scmi_msg msg; + struct list_head node; +}; + +/** + * struct scmi_dbg_raw_data - Structure holding data needed by the debugfs + * layer + * + * @chan_id: The preferred channel to use: if zero the channel is automatically + * selected based on protocol. + * @raw: A reference to the Raw instance. + * @tx: A message buffer used to collect TX message on write. + * @tx_size: The effective size of the TX message. + * @tx_req_size: The final expected size of the complete TX message. + * @rx: A message buffer to collect RX message on read. + * @rx_size: The effective size of the RX message. + */ +struct scmi_dbg_raw_data { + u8 chan_id; + struct scmi_raw_mode_info *raw; + struct scmi_msg tx; + size_t tx_size; + size_t tx_req_size; + struct scmi_msg rx; + size_t rx_size; +}; + +static struct scmi_raw_queue * +scmi_raw_queue_select(struct scmi_raw_mode_info *raw, unsigned int idx, + unsigned int chan_id) +{ + if (!chan_id) + return raw->q[idx]; + + return xa_load(&raw->chans_q, chan_id); +} + +static struct scmi_raw_buffer *scmi_raw_buffer_get(struct scmi_raw_queue *q) +{ + unsigned long flags; + struct scmi_raw_buffer *rb = NULL; + struct list_head *head = &q->free_bufs; + + spin_lock_irqsave(&q->free_bufs_lock, flags); + if (!list_empty(head)) { + rb = list_first_entry(head, struct scmi_raw_buffer, node); + list_del_init(&rb->node); + } + spin_unlock_irqrestore(&q->free_bufs_lock, flags); + + return rb; +} + +static void scmi_raw_buffer_put(struct scmi_raw_queue *q, + struct scmi_raw_buffer *rb) +{ + unsigned long flags; + + /* Reset to full buffer length */ + rb->msg.len = rb->max_len; + + spin_lock_irqsave(&q->free_bufs_lock, flags); + list_add_tail(&rb->node, &q->free_bufs); + spin_unlock_irqrestore(&q->free_bufs_lock, flags); +} + +static void scmi_raw_buffer_enqueue(struct scmi_raw_queue *q, + struct scmi_raw_buffer *rb) +{ + unsigned long flags; + + spin_lock_irqsave(&q->msg_q_lock, flags); + list_add_tail(&rb->node, &q->msg_q); + spin_unlock_irqrestore(&q->msg_q_lock, flags); + + wake_up_interruptible(&q->wq); +} + +static struct scmi_raw_buffer* +scmi_raw_buffer_dequeue_unlocked(struct scmi_raw_queue *q) +{ + struct scmi_raw_buffer *rb = NULL; + + if (!list_empty(&q->msg_q)) { + rb = list_first_entry(&q->msg_q, struct scmi_raw_buffer, node); + list_del_init(&rb->node); + } + + return rb; +} + +static struct scmi_raw_buffer *scmi_raw_buffer_dequeue(struct scmi_raw_queue *q) +{ + unsigned long flags; + struct scmi_raw_buffer *rb; + + spin_lock_irqsave(&q->msg_q_lock, flags); + rb = scmi_raw_buffer_dequeue_unlocked(q); + spin_unlock_irqrestore(&q->msg_q_lock, flags); + + return rb; +} + +static void scmi_raw_buffer_queue_flush(struct scmi_raw_queue *q) +{ + struct scmi_raw_buffer *rb; + + do { + rb = scmi_raw_buffer_dequeue(q); + if (rb) + scmi_raw_buffer_put(q, rb); + } while (rb); +} + +static struct scmi_xfer_raw_waiter * +scmi_xfer_raw_waiter_get(struct scmi_raw_mode_info *raw, struct scmi_xfer *xfer, + struct scmi_chan_info *cinfo, bool async) +{ + struct scmi_xfer_raw_waiter *rw = NULL; + + mutex_lock(&raw->free_mtx); + if (!list_empty(&raw->free_waiters)) { + rw = list_first_entry(&raw->free_waiters, + struct scmi_xfer_raw_waiter, node); + list_del_init(&rw->node); + + if (async) { + reinit_completion(&rw->async_response); + xfer->async_done = &rw->async_response; + } + + rw->cinfo = cinfo; + rw->xfer = xfer; + } + mutex_unlock(&raw->free_mtx); + + return rw; +} + +static void scmi_xfer_raw_waiter_put(struct scmi_raw_mode_info *raw, + struct scmi_xfer_raw_waiter *rw) +{ + if (rw->xfer) { + rw->xfer->async_done = NULL; + rw->xfer = NULL; + } + + mutex_lock(&raw->free_mtx); + list_add_tail(&rw->node, &raw->free_waiters); + mutex_unlock(&raw->free_mtx); +} + +static void scmi_xfer_raw_waiter_enqueue(struct scmi_raw_mode_info *raw, + struct scmi_xfer_raw_waiter *rw) +{ + /* A timestamp for the deferred worker to know how much this has aged */ + rw->start_jiffies = jiffies; + + trace_scmi_xfer_response_wait(rw->xfer->transfer_id, rw->xfer->hdr.id, + rw->xfer->hdr.protocol_id, + rw->xfer->hdr.seq, + raw->desc->max_rx_timeout_ms, + rw->xfer->hdr.poll_completion); + + mutex_lock(&raw->active_mtx); + list_add_tail(&rw->node, &raw->active_waiters); + mutex_unlock(&raw->active_mtx); + + /* kick waiter work */ + queue_work(raw->wait_wq, &raw->waiters_work); +} + +static struct scmi_xfer_raw_waiter * +scmi_xfer_raw_waiter_dequeue(struct scmi_raw_mode_info *raw) +{ + struct scmi_xfer_raw_waiter *rw = NULL; + + mutex_lock(&raw->active_mtx); + if (!list_empty(&raw->active_waiters)) { + rw = list_first_entry(&raw->active_waiters, + struct scmi_xfer_raw_waiter, node); + list_del_init(&rw->node); + } + mutex_unlock(&raw->active_mtx); + + return rw; +} + +/** + * scmi_xfer_raw_worker - Work function to wait for Raw xfers completions + * + * @work: A reference to the work. + * + * In SCMI Raw mode, once a user-provided injected SCMI message is sent, we + * cannot wait to receive its response (if any) in the context of the injection + * routines so as not to leave the userspace write syscall, which delivered the + * SCMI message to send, pending till eventually a reply is received. + * Userspace should and will poll/wait instead on the read syscalls which will + * be in charge of reading a received reply (if any). + * + * Even though reply messages are collected and reported into the SCMI Raw layer + * on the RX path, nonetheless we have to properly wait for their completion as + * usual (and async_completion too if needed) in order to properly release the + * xfer structure at the end: to do this out of the context of the write/send + * these waiting jobs are delegated to this deferred worker. + * + * Any sent xfer, to be waited for, is timestamped and queued for later + * consumption by this worker: queue aging is accounted for while choosing a + * timeout for the completion, BUT we do not really care here if we end up + * accidentally waiting for a bit too long. + */ +static void scmi_xfer_raw_worker(struct work_struct *work) +{ + struct scmi_raw_mode_info *raw; + struct device *dev; + unsigned long max_tmo; + + raw = container_of(work, struct scmi_raw_mode_info, waiters_work); + dev = raw->handle->dev; + max_tmo = msecs_to_jiffies(raw->desc->max_rx_timeout_ms); + + do { + int ret = 0; + unsigned int timeout_ms; + unsigned long aging; + struct scmi_xfer *xfer; + struct scmi_xfer_raw_waiter *rw; + struct scmi_chan_info *cinfo; + + rw = scmi_xfer_raw_waiter_dequeue(raw); + if (!rw) + return; + + cinfo = rw->cinfo; + xfer = rw->xfer; + /* + * Waiters are queued by wait-deadline at the end, so some of + * them could have been already expired when processed, BUT we + * have to check the completion status anyway just in case a + * virtually expired (aged) transaction was indeed completed + * fine and we'll have to wait for the asynchronous part (if + * any): for this reason a 1 ms timeout is used for already + * expired/aged xfers. + */ + aging = jiffies - rw->start_jiffies; + timeout_ms = max_tmo > aging ? + jiffies_to_msecs(max_tmo - aging) : 1; + + ret = scmi_xfer_raw_wait_for_message_response(cinfo, xfer, + timeout_ms); + if (!ret && xfer->hdr.status) + ret = scmi_to_linux_errno(xfer->hdr.status); + + if (raw->desc->ops->mark_txdone) + raw->desc->ops->mark_txdone(rw->cinfo, ret, xfer); + + trace_scmi_xfer_end(xfer->transfer_id, xfer->hdr.id, + xfer->hdr.protocol_id, xfer->hdr.seq, ret); + + /* Wait also for an async delayed response if needed */ + if (!ret && xfer->async_done) { + unsigned long tmo = msecs_to_jiffies(SCMI_MAX_RESPONSE_TIMEOUT); + + if (!wait_for_completion_timeout(xfer->async_done, tmo)) + dev_err(dev, + "timed out in RAW delayed resp - HDR:%08X\n", + pack_scmi_header(&xfer->hdr)); + } + + /* Release waiter and xfer */ + scmi_xfer_raw_put(raw->handle, xfer); + scmi_xfer_raw_waiter_put(raw, rw); + } while (1); +} + +static void scmi_xfer_raw_reset(struct scmi_raw_mode_info *raw) +{ + int i; + + dev_info(raw->handle->dev, "Resetting SCMI Raw stack.\n"); + + for (i = 0; i < SCMI_RAW_MAX_QUEUE; i++) + scmi_raw_buffer_queue_flush(raw->q[i]); +} + +/** + * scmi_xfer_raw_get_init - An helper to build a valid xfer from the provided + * bare SCMI message. + * + * @raw: A reference to the Raw instance. + * @buf: A buffer containing the whole SCMI message to send (including the + * header) in little-endian binary formmat. + * @len: Length of the message in @buf. + * @p: A pointer to return the initialized Raw xfer. + * + * After an xfer is picked from the TX pool and filled in with the message + * content, the xfer is registered as pending with the core in the usual way + * using the original sequence number provided by the user with the message. + * + * Note that, in case the testing user application is NOT using distinct + * sequence-numbers between successive SCMI messages such registration could + * fail temporarily if the previous message, using the same sequence number, + * had still not released; in such a case we just wait and retry. + * + * Return: 0 on Success + */ +static int scmi_xfer_raw_get_init(struct scmi_raw_mode_info *raw, void *buf, + size_t len, struct scmi_xfer **p) +{ + u32 msg_hdr; + size_t tx_size; + struct scmi_xfer *xfer; + int ret, retry = SCMI_XFER_RAW_MAX_RETRIES; + struct device *dev = raw->handle->dev; + + if (!buf || len < sizeof(u32)) + return -EINVAL; + + tx_size = len - sizeof(u32); + /* Ensure we have sane transfer sizes */ + if (tx_size > raw->desc->max_msg_size) + return -ERANGE; + + xfer = scmi_xfer_raw_get(raw->handle); + if (IS_ERR(xfer)) { + dev_warn(dev, "RAW - Cannot get a free RAW xfer !\n"); + return PTR_ERR(xfer); + } + + /* Build xfer from the provided SCMI bare LE message */ + msg_hdr = le32_to_cpu(*((__le32 *)buf)); + unpack_scmi_header(msg_hdr, &xfer->hdr); + xfer->hdr.seq = (u16)MSG_XTRACT_TOKEN(msg_hdr); + /* Polling not supported */ + xfer->hdr.poll_completion = false; + xfer->hdr.status = SCMI_SUCCESS; + xfer->tx.len = tx_size; + xfer->rx.len = raw->desc->max_msg_size; + /* Clear the whole TX buffer */ + memset(xfer->tx.buf, 0x00, raw->desc->max_msg_size); + if (xfer->tx.len) + memcpy(xfer->tx.buf, (u8 *)buf + sizeof(msg_hdr), xfer->tx.len); + *p = xfer; + + /* + * In flight registration can temporarily fail in case of Raw messages + * if the user injects messages without using monotonically increasing + * sequence numbers since, in Raw mode, the xfer (and the token) is + * finally released later by a deferred worker. Just retry for a while. + */ + do { + ret = scmi_xfer_raw_inflight_register(raw->handle, xfer); + if (ret) { + dev_dbg(dev, + "...retrying[%d] inflight registration\n", + retry); + msleep(raw->desc->max_rx_timeout_ms / + SCMI_XFER_RAW_MAX_RETRIES); + } + } while (ret && --retry); + + if (ret) { + dev_warn(dev, + "RAW - Could NOT register xfer %d in-flight HDR:0x%08X\n", + xfer->hdr.seq, msg_hdr); + scmi_xfer_raw_put(raw->handle, xfer); + } + + return ret; +} + +/** + * scmi_do_xfer_raw_start - An helper to send a valid raw xfer + * + * @raw: A reference to the Raw instance. + * @xfer: The xfer to send + * @chan_id: The channel ID to use, if zero the channels is automatically + * selected based on the protocol used. + * @async: A flag stating if an asynchronous command is required. + * + * This function send a previously built raw xfer using an appropriate channel + * and queues the related waiting work. + * + * Note that we need to know explicitly if the required command is meant to be + * asynchronous in kind since we have to properly setup the waiter. + * (and deducing this from the payload is weak and do not scale given there is + * NOT a common header-flag stating if the command is asynchronous or not) + * + * Return: 0 on Success + */ +static int scmi_do_xfer_raw_start(struct scmi_raw_mode_info *raw, + struct scmi_xfer *xfer, u8 chan_id, + bool async) +{ + int ret; + struct scmi_chan_info *cinfo; + struct scmi_xfer_raw_waiter *rw; + struct device *dev = raw->handle->dev; + + if (!chan_id) + chan_id = xfer->hdr.protocol_id; + else + xfer->flags |= SCMI_XFER_FLAG_CHAN_SET; + + cinfo = scmi_xfer_raw_channel_get(raw->handle, chan_id); + if (IS_ERR(cinfo)) + return PTR_ERR(cinfo); + + rw = scmi_xfer_raw_waiter_get(raw, xfer, cinfo, async); + if (!rw) { + dev_warn(dev, "RAW - Cannot get a free waiter !\n"); + return -ENOMEM; + } + + /* True ONLY if also supported by transport. */ + if (is_polling_enabled(cinfo, raw->desc)) + xfer->hdr.poll_completion = true; + + reinit_completion(&xfer->done); + /* Make sure xfer state update is visible before sending */ + smp_store_mb(xfer->state, SCMI_XFER_SENT_OK); + + trace_scmi_xfer_begin(xfer->transfer_id, xfer->hdr.id, + xfer->hdr.protocol_id, xfer->hdr.seq, + xfer->hdr.poll_completion); + + ret = raw->desc->ops->send_message(rw->cinfo, xfer); + if (ret) { + dev_err(dev, "Failed to send RAW message %d\n", ret); + scmi_xfer_raw_waiter_put(raw, rw); + return ret; + } + + trace_scmi_msg_dump(raw->id, cinfo->id, xfer->hdr.protocol_id, + xfer->hdr.id, "cmnd", xfer->hdr.seq, + xfer->hdr.status, + xfer->tx.buf, xfer->tx.len); + + scmi_xfer_raw_waiter_enqueue(raw, rw); + + return ret; +} + +/** + * scmi_raw_message_send - An helper to build and send an SCMI command using + * the provided SCMI bare message buffer + * + * @raw: A reference to the Raw instance. + * @buf: A buffer containing the whole SCMI message to send (including the + * header) in little-endian binary format. + * @len: Length of the message in @buf. + * @chan_id: The channel ID to use. + * @async: A flag stating if an asynchronous command is required. + * + * Return: 0 on Success + */ +static int scmi_raw_message_send(struct scmi_raw_mode_info *raw, + void *buf, size_t len, u8 chan_id, bool async) +{ + int ret; + struct scmi_xfer *xfer; + + ret = scmi_xfer_raw_get_init(raw, buf, len, &xfer); + if (ret) + return ret; + + ret = scmi_do_xfer_raw_start(raw, xfer, chan_id, async); + if (ret) + scmi_xfer_raw_put(raw->handle, xfer); + + return ret; +} + +static struct scmi_raw_buffer * +scmi_raw_message_dequeue(struct scmi_raw_queue *q, bool o_nonblock) +{ + unsigned long flags; + struct scmi_raw_buffer *rb; + + spin_lock_irqsave(&q->msg_q_lock, flags); + while (list_empty(&q->msg_q)) { + spin_unlock_irqrestore(&q->msg_q_lock, flags); + + if (o_nonblock) + return ERR_PTR(-EAGAIN); + + if (wait_event_interruptible(q->wq, !list_empty(&q->msg_q))) + return ERR_PTR(-ERESTARTSYS); + + spin_lock_irqsave(&q->msg_q_lock, flags); + } + + rb = scmi_raw_buffer_dequeue_unlocked(q); + + spin_unlock_irqrestore(&q->msg_q_lock, flags); + + return rb; +} + +/** + * scmi_raw_message_receive - An helper to dequeue and report the next + * available enqueued raw message payload that has been collected. + * + * @raw: A reference to the Raw instance. + * @buf: A buffer to get hold of the whole SCMI message received and represented + * in little-endian binary format. + * @len: Length of @buf. + * @size: The effective size of the message copied into @buf + * @idx: The index of the queue to pick the next queued message from. + * @chan_id: The channel ID to use. + * @o_nonblock: A flag to request a non-blocking message dequeue. + * + * Return: 0 on Success + */ +static int scmi_raw_message_receive(struct scmi_raw_mode_info *raw, + void *buf, size_t len, size_t *size, + unsigned int idx, unsigned int chan_id, + bool o_nonblock) +{ + int ret = 0; + struct scmi_raw_buffer *rb; + struct scmi_raw_queue *q; + + q = scmi_raw_queue_select(raw, idx, chan_id); + if (!q) + return -ENODEV; + + rb = scmi_raw_message_dequeue(q, o_nonblock); + if (IS_ERR(rb)) { + dev_dbg(raw->handle->dev, "RAW - No message available!\n"); + return PTR_ERR(rb); + } + + if (rb->msg.len <= len) { + memcpy(buf, rb->msg.buf, rb->msg.len); + *size = rb->msg.len; + } else { + ret = -ENOSPC; + } + + scmi_raw_buffer_put(q, rb); + + return ret; +} + +/* SCMI Raw debugfs helpers */ + +static ssize_t scmi_dbg_raw_mode_common_read(struct file *filp, + char __user *buf, + size_t count, loff_t *ppos, + unsigned int idx) +{ + ssize_t cnt; + struct scmi_dbg_raw_data *rd = filp->private_data; + + if (!rd->rx_size) { + int ret; + + ret = scmi_raw_message_receive(rd->raw, rd->rx.buf, rd->rx.len, + &rd->rx_size, idx, rd->chan_id, + filp->f_flags & O_NONBLOCK); + if (ret) { + rd->rx_size = 0; + return ret; + } + + /* Reset any previous filepos change, including writes */ + *ppos = 0; + } else if (*ppos == rd->rx_size) { + /* Return EOF once all the message has been read-out */ + rd->rx_size = 0; + return 0; + } + + cnt = simple_read_from_buffer(buf, count, ppos, + rd->rx.buf, rd->rx_size); + + return cnt; +} + +static ssize_t scmi_dbg_raw_mode_common_write(struct file *filp, + const char __user *buf, + size_t count, loff_t *ppos, + bool async) +{ + int ret; + struct scmi_dbg_raw_data *rd = filp->private_data; + + if (count > rd->tx.len - rd->tx_size) + return -ENOSPC; + + /* On first write attempt @count carries the total full message size. */ + if (!rd->tx_size) + rd->tx_req_size = count; + + /* + * Gather a full message, possibly across multiple interrupted wrrtes, + * before sending it with a single RAW xfer. + */ + if (rd->tx_size < rd->tx_req_size) { + size_t cnt; + + cnt = simple_write_to_buffer(rd->tx.buf, rd->tx.len, ppos, + buf, count); + rd->tx_size += cnt; + if (cnt < count) + return cnt; + } + + ret = scmi_raw_message_send(rd->raw, rd->tx.buf, rd->tx_size, + rd->chan_id, async); + + /* Reset ppos for next message ... */ + rd->tx_size = 0; + *ppos = 0; + + return ret ?: count; +} + +static __poll_t scmi_test_dbg_raw_common_poll(struct file *filp, + struct poll_table_struct *wait, + unsigned int idx) +{ + unsigned long flags; + struct scmi_dbg_raw_data *rd = filp->private_data; + struct scmi_raw_queue *q; + __poll_t mask = 0; + + q = scmi_raw_queue_select(rd->raw, idx, rd->chan_id); + if (!q) + return mask; + + poll_wait(filp, &q->wq, wait); + + spin_lock_irqsave(&q->msg_q_lock, flags); + if (!list_empty(&q->msg_q)) + mask = EPOLLIN | EPOLLRDNORM; + spin_unlock_irqrestore(&q->msg_q_lock, flags); + + return mask; +} + +static ssize_t scmi_dbg_raw_mode_message_read(struct file *filp, + char __user *buf, + size_t count, loff_t *ppos) +{ + return scmi_dbg_raw_mode_common_read(filp, buf, count, ppos, + SCMI_RAW_REPLY_QUEUE); +} + +static ssize_t scmi_dbg_raw_mode_message_write(struct file *filp, + const char __user *buf, + size_t count, loff_t *ppos) +{ + return scmi_dbg_raw_mode_common_write(filp, buf, count, ppos, false); +} + +static __poll_t scmi_dbg_raw_mode_message_poll(struct file *filp, + struct poll_table_struct *wait) +{ + return scmi_test_dbg_raw_common_poll(filp, wait, SCMI_RAW_REPLY_QUEUE); +} + +static int scmi_dbg_raw_mode_open(struct inode *inode, struct file *filp) +{ + u8 id; + struct scmi_raw_mode_info *raw; + struct scmi_dbg_raw_data *rd; + const char *id_str = filp->f_path.dentry->d_parent->d_name.name; + + if (!inode->i_private) + return -ENODEV; + + raw = inode->i_private; + rd = kzalloc(sizeof(*rd), GFP_KERNEL); + if (!rd) + return -ENOMEM; + + rd->rx.len = raw->desc->max_msg_size + sizeof(u32); + rd->rx.buf = kzalloc(rd->rx.len, GFP_KERNEL); + if (!rd->rx.buf) { + kfree(rd); + return -ENOMEM; + } + + rd->tx.len = raw->desc->max_msg_size + sizeof(u32); + rd->tx.buf = kzalloc(rd->tx.len, GFP_KERNEL); + if (!rd->tx.buf) { + kfree(rd->rx.buf); + kfree(rd); + return -ENOMEM; + } + + /* Grab channel ID from debugfs entry naming if any */ + if (!kstrtou8(id_str, 16, &id)) + rd->chan_id = id; + + rd->raw = raw; + filp->private_data = rd; + + return 0; +} + +static int scmi_dbg_raw_mode_release(struct inode *inode, struct file *filp) +{ + struct scmi_dbg_raw_data *rd = filp->private_data; + + kfree(rd->rx.buf); + kfree(rd->tx.buf); + kfree(rd); + + return 0; +} + +static ssize_t scmi_dbg_raw_mode_reset_write(struct file *filp, + const char __user *buf, + size_t count, loff_t *ppos) +{ + struct scmi_dbg_raw_data *rd = filp->private_data; + + scmi_xfer_raw_reset(rd->raw); + + return count; +} + +static const struct file_operations scmi_dbg_raw_mode_reset_fops = { + .open = scmi_dbg_raw_mode_open, + .release = scmi_dbg_raw_mode_release, + .write = scmi_dbg_raw_mode_reset_write, + .owner = THIS_MODULE, +}; + +static const struct file_operations scmi_dbg_raw_mode_message_fops = { + .open = scmi_dbg_raw_mode_open, + .release = scmi_dbg_raw_mode_release, + .read = scmi_dbg_raw_mode_message_read, + .write = scmi_dbg_raw_mode_message_write, + .poll = scmi_dbg_raw_mode_message_poll, + .owner = THIS_MODULE, +}; + +static ssize_t scmi_dbg_raw_mode_message_async_write(struct file *filp, + const char __user *buf, + size_t count, loff_t *ppos) +{ + return scmi_dbg_raw_mode_common_write(filp, buf, count, ppos, true); +} + +static const struct file_operations scmi_dbg_raw_mode_message_async_fops = { + .open = scmi_dbg_raw_mode_open, + .release = scmi_dbg_raw_mode_release, + .read = scmi_dbg_raw_mode_message_read, + .write = scmi_dbg_raw_mode_message_async_write, + .poll = scmi_dbg_raw_mode_message_poll, + .owner = THIS_MODULE, +}; + +static ssize_t scmi_test_dbg_raw_mode_notif_read(struct file *filp, + char __user *buf, + size_t count, loff_t *ppos) +{ + return scmi_dbg_raw_mode_common_read(filp, buf, count, ppos, + SCMI_RAW_NOTIF_QUEUE); +} + +static __poll_t +scmi_test_dbg_raw_mode_notif_poll(struct file *filp, + struct poll_table_struct *wait) +{ + return scmi_test_dbg_raw_common_poll(filp, wait, SCMI_RAW_NOTIF_QUEUE); +} + +static const struct file_operations scmi_dbg_raw_mode_notification_fops = { + .open = scmi_dbg_raw_mode_open, + .release = scmi_dbg_raw_mode_release, + .read = scmi_test_dbg_raw_mode_notif_read, + .poll = scmi_test_dbg_raw_mode_notif_poll, + .owner = THIS_MODULE, +}; + +static ssize_t scmi_test_dbg_raw_mode_errors_read(struct file *filp, + char __user *buf, + size_t count, loff_t *ppos) +{ + return scmi_dbg_raw_mode_common_read(filp, buf, count, ppos, + SCMI_RAW_ERRS_QUEUE); +} + +static __poll_t +scmi_test_dbg_raw_mode_errors_poll(struct file *filp, + struct poll_table_struct *wait) +{ + return scmi_test_dbg_raw_common_poll(filp, wait, SCMI_RAW_ERRS_QUEUE); +} + +static const struct file_operations scmi_dbg_raw_mode_errors_fops = { + .open = scmi_dbg_raw_mode_open, + .release = scmi_dbg_raw_mode_release, + .read = scmi_test_dbg_raw_mode_errors_read, + .poll = scmi_test_dbg_raw_mode_errors_poll, + .owner = THIS_MODULE, +}; + +static struct scmi_raw_queue * +scmi_raw_queue_init(struct scmi_raw_mode_info *raw) +{ + int i; + struct scmi_raw_buffer *rb; + struct device *dev = raw->handle->dev; + struct scmi_raw_queue *q; + + q = devm_kzalloc(dev, sizeof(*q), GFP_KERNEL); + if (!q) + return ERR_PTR(-ENOMEM); + + rb = devm_kcalloc(dev, raw->tx_max_msg, sizeof(*rb), GFP_KERNEL); + if (!rb) + return ERR_PTR(-ENOMEM); + + spin_lock_init(&q->free_bufs_lock); + INIT_LIST_HEAD(&q->free_bufs); + for (i = 0; i < raw->tx_max_msg; i++, rb++) { + rb->max_len = raw->desc->max_msg_size + sizeof(u32); + rb->msg.buf = devm_kzalloc(dev, rb->max_len, GFP_KERNEL); + if (!rb->msg.buf) + return ERR_PTR(-ENOMEM); + scmi_raw_buffer_put(q, rb); + } + + spin_lock_init(&q->msg_q_lock); + INIT_LIST_HEAD(&q->msg_q); + init_waitqueue_head(&q->wq); + + return q; +} + +static int scmi_xfer_raw_worker_init(struct scmi_raw_mode_info *raw) +{ + int i; + struct scmi_xfer_raw_waiter *rw; + struct device *dev = raw->handle->dev; + + rw = devm_kcalloc(dev, raw->tx_max_msg, sizeof(*rw), GFP_KERNEL); + if (!rw) + return -ENOMEM; + + raw->wait_wq = alloc_workqueue("scmi-raw-wait-wq-%d", + WQ_UNBOUND | WQ_FREEZABLE | + WQ_HIGHPRI, WQ_SYSFS, raw->id); + if (!raw->wait_wq) + return -ENOMEM; + + mutex_init(&raw->free_mtx); + INIT_LIST_HEAD(&raw->free_waiters); + mutex_init(&raw->active_mtx); + INIT_LIST_HEAD(&raw->active_waiters); + + for (i = 0; i < raw->tx_max_msg; i++, rw++) { + init_completion(&rw->async_response); + scmi_xfer_raw_waiter_put(raw, rw); + } + INIT_WORK(&raw->waiters_work, scmi_xfer_raw_worker); + + return 0; +} + +static int scmi_raw_mode_setup(struct scmi_raw_mode_info *raw, + u8 *channels, int num_chans) +{ + int ret, idx; + void *gid; + struct device *dev = raw->handle->dev; + + gid = devres_open_group(dev, NULL, GFP_KERNEL); + if (!gid) + return -ENOMEM; + + for (idx = 0; idx < SCMI_RAW_MAX_QUEUE; idx++) { + raw->q[idx] = scmi_raw_queue_init(raw); + if (IS_ERR(raw->q[idx])) { + ret = PTR_ERR(raw->q[idx]); + goto err; + } + } + + xa_init(&raw->chans_q); + if (num_chans > 1) { + int i; + + for (i = 0; i < num_chans; i++) { + void *xret; + struct scmi_raw_queue *q; + + q = scmi_raw_queue_init(raw); + if (IS_ERR(q)) { + ret = PTR_ERR(q); + goto err_xa; + } + + xret = xa_store(&raw->chans_q, channels[i], q, + GFP_KERNEL); + if (xa_err(xret)) { + dev_err(dev, + "Fail to allocate Raw queue 0x%02X\n", + channels[i]); + ret = xa_err(xret); + goto err_xa; + } + } + } + + ret = scmi_xfer_raw_worker_init(raw); + if (ret) + goto err_xa; + + devres_close_group(dev, gid); + raw->gid = gid; + + return 0; + +err_xa: + xa_destroy(&raw->chans_q); +err: + devres_release_group(dev, gid); + return ret; +} + +/** + * scmi_raw_mode_init - Function to initialize the SCMI Raw stack + * + * @handle: Pointer to SCMI entity handle + * @top_dentry: A reference to the top Raw debugfs dentry + * @instance_id: The ID of the underlying SCMI platform instance represented by + * this Raw instance + * @channels: The list of the existing channels + * @num_chans: The number of entries in @channels + * @desc: Reference to the transport operations + * @tx_max_msg: Max number of in-flight messages allowed by the transport + * + * This function prepare the SCMI Raw stack and creates the debugfs API. + * + * Return: An opaque handle to the Raw instance on Success, an ERR_PTR otherwise + */ +void *scmi_raw_mode_init(const struct scmi_handle *handle, + struct dentry *top_dentry, int instance_id, + u8 *channels, int num_chans, + const struct scmi_desc *desc, int tx_max_msg) +{ + int ret; + struct scmi_raw_mode_info *raw; + struct device *dev; + + if (!handle || !desc) + return ERR_PTR(-EINVAL); + + dev = handle->dev; + raw = devm_kzalloc(dev, sizeof(*raw), GFP_KERNEL); + if (!raw) + return ERR_PTR(-ENOMEM); + + raw->handle = handle; + raw->desc = desc; + raw->tx_max_msg = tx_max_msg; + raw->id = instance_id; + + ret = scmi_raw_mode_setup(raw, channels, num_chans); + if (ret) { + devm_kfree(dev, raw); + return ERR_PTR(ret); + } + + raw->dentry = debugfs_create_dir("raw", top_dentry); + + debugfs_create_file("reset", 0200, raw->dentry, raw, + &scmi_dbg_raw_mode_reset_fops); + + debugfs_create_file("message", 0600, raw->dentry, raw, + &scmi_dbg_raw_mode_message_fops); + + debugfs_create_file("message_async", 0600, raw->dentry, raw, + &scmi_dbg_raw_mode_message_async_fops); + + debugfs_create_file("notification", 0400, raw->dentry, raw, + &scmi_dbg_raw_mode_notification_fops); + + debugfs_create_file("errors", 0400, raw->dentry, raw, + &scmi_dbg_raw_mode_errors_fops); + + /* + * Expose per-channel entries if multiple channels available. + * Just ignore errors while setting up these interfaces since we + * have anyway already a working core Raw support. + */ + if (num_chans > 1) { + int i; + struct dentry *top_chans; + + top_chans = debugfs_create_dir("channels", raw->dentry); + + for (i = 0; i < num_chans; i++) { + char cdir[8]; + struct dentry *chd; + + snprintf(cdir, 8, "0x%02X", channels[i]); + chd = debugfs_create_dir(cdir, top_chans); + + debugfs_create_file("message", 0600, chd, raw, + &scmi_dbg_raw_mode_message_fops); + + debugfs_create_file("message_async", 0600, chd, raw, + &scmi_dbg_raw_mode_message_async_fops); + } + } + + dev_info(dev, "SCMI RAW Mode initialized for instance %d\n", raw->id); + + return raw; +} + +/** + * scmi_raw_mode_cleanup - Function to cleanup the SCMI Raw stack + * + * @r: An opaque handle to an initialized SCMI Raw instance + */ +void scmi_raw_mode_cleanup(void *r) +{ + struct scmi_raw_mode_info *raw = r; + + if (!raw) + return; + + debugfs_remove_recursive(raw->dentry); + + cancel_work_sync(&raw->waiters_work); + destroy_workqueue(raw->wait_wq); + xa_destroy(&raw->chans_q); +} + +static int scmi_xfer_raw_collect(void *msg, size_t *msg_len, + struct scmi_xfer *xfer) +{ + __le32 *m; + size_t msg_size; + + if (!xfer || !msg || !msg_len) + return -EINVAL; + + /* Account for hdr ...*/ + msg_size = xfer->rx.len + sizeof(u32); + /* ... and status if needed */ + if (xfer->hdr.type != MSG_TYPE_NOTIFICATION) + msg_size += sizeof(u32); + + if (msg_size > *msg_len) + return -ENOSPC; + + m = msg; + *m = cpu_to_le32(pack_scmi_header(&xfer->hdr)); + if (xfer->hdr.type != MSG_TYPE_NOTIFICATION) + *++m = cpu_to_le32(xfer->hdr.status); + + memcpy(++m, xfer->rx.buf, xfer->rx.len); + + *msg_len = msg_size; + + return 0; +} + +/** + * scmi_raw_message_report - Helper to report back valid reponses/notifications + * to raw message requests. + * + * @r: An opaque reference to the raw instance configuration + * @xfer: The xfer containing the message to be reported + * @idx: The index of the queue. + * @chan_id: The channel ID to use. + * + * If Raw mode is enabled, this is called from the SCMI core on the regular RX + * path to save and enqueue the response/notification payload carried by this + * xfer into a dedicated scmi_raw_buffer for later consumption by the user. + * + * This way the caller can free the related xfer immediately afterwards and the + * user can read back the raw message payload at its own pace (if ever) without + * holding an xfer for too long. + */ +void scmi_raw_message_report(void *r, struct scmi_xfer *xfer, + unsigned int idx, unsigned int chan_id) +{ + int ret; + unsigned long flags; + struct scmi_raw_buffer *rb; + struct device *dev; + struct scmi_raw_queue *q; + struct scmi_raw_mode_info *raw = r; + + if (!raw || (idx == SCMI_RAW_REPLY_QUEUE && !SCMI_XFER_IS_RAW(xfer))) + return; + + dev = raw->handle->dev; + q = scmi_raw_queue_select(raw, idx, + SCMI_XFER_IS_CHAN_SET(xfer) ? chan_id : 0); + + /* + * Grab the msg_q_lock upfront to avoid a possible race between + * realizing the free list was empty and effectively picking the next + * buffer to use from the oldest one enqueued and still unread on this + * msg_q. + * + * Note that nowhere else these locks are taken together, so no risk of + * deadlocks du eto inversion. + */ + spin_lock_irqsave(&q->msg_q_lock, flags); + rb = scmi_raw_buffer_get(q); + if (!rb) { + /* + * Immediate and delayed replies to previously injected Raw + * commands MUST be read back from userspace to free the buffers: + * if this is not happening something is seriously broken and + * must be fixed at the application level: complain loudly. + */ + if (idx == SCMI_RAW_REPLY_QUEUE) { + spin_unlock_irqrestore(&q->msg_q_lock, flags); + dev_warn(dev, + "RAW[%d] - Buffers exhausted. Dropping report.\n", + idx); + return; + } + + /* + * Notifications and errors queues are instead handled in a + * circular manner: unread old buffers are just overwritten by + * newer ones. + * + * The main reason for this is that notifications originated + * by Raw requests cannot be distinguished from normal ones, so + * your Raw buffers queues risk to be flooded and depleted by + * notifications if you left it mistakenly enabled or when in + * coexistence mode. + */ + rb = scmi_raw_buffer_dequeue_unlocked(q); + if (WARN_ON(!rb)) { + spin_unlock_irqrestore(&q->msg_q_lock, flags); + return; + } + + /* Reset to full buffer length */ + rb->msg.len = rb->max_len; + + dev_warn_once(dev, + "RAW[%d] - Buffers exhausted. Re-using oldest.\n", + idx); + } + spin_unlock_irqrestore(&q->msg_q_lock, flags); + + ret = scmi_xfer_raw_collect(rb->msg.buf, &rb->msg.len, xfer); + if (ret) { + dev_warn(dev, "RAW - Cannot collect xfer into buffer !\n"); + scmi_raw_buffer_put(q, rb); + return; + } + + scmi_raw_buffer_enqueue(q, rb); +} + +static void scmi_xfer_raw_fill(struct scmi_raw_mode_info *raw, + struct scmi_chan_info *cinfo, + struct scmi_xfer *xfer, u32 msg_hdr) +{ + /* Unpack received HDR as it is */ + unpack_scmi_header(msg_hdr, &xfer->hdr); + xfer->hdr.seq = MSG_XTRACT_TOKEN(msg_hdr); + + memset(xfer->rx.buf, 0x00, xfer->rx.len); + + raw->desc->ops->fetch_response(cinfo, xfer); +} + +/** + * scmi_raw_error_report - Helper to report back timed-out or generally + * unexpected replies. + * + * @r: An opaque reference to the raw instance configuration + * @cinfo: A reference to the channel to use to retrieve the broken xfer + * @msg_hdr: The SCMI message header of the message to fetch and report + * @priv: Any private data related to the xfer. + * + * If Raw mode is enabled, this is called from the SCMI core on the RX path in + * case of errors to save and enqueue the bad message payload carried by the + * message that has just been received. + * + * Note that we have to manually fetch any available payload into a temporary + * xfer to be able to save and enqueue the message, since the regular RX error + * path which had called this would have not fetched the message payload having + * classified it as an error. + */ +void scmi_raw_error_report(void *r, struct scmi_chan_info *cinfo, + u32 msg_hdr, void *priv) +{ + struct scmi_xfer xfer; + struct scmi_raw_mode_info *raw = r; + + if (!raw) + return; + + xfer.rx.len = raw->desc->max_msg_size; + xfer.rx.buf = kzalloc(xfer.rx.len, GFP_ATOMIC); + if (!xfer.rx.buf) { + dev_info(raw->handle->dev, + "Cannot report Raw error for HDR:0x%X - ENOMEM\n", + msg_hdr); + return; + } + + /* Any transport-provided priv must be passed back down to transport */ + if (priv) + /* Ensure priv is visible */ + smp_store_mb(xfer.priv, priv); + + scmi_xfer_raw_fill(raw, cinfo, &xfer, msg_hdr); + scmi_raw_message_report(raw, &xfer, SCMI_RAW_ERRS_QUEUE, 0); + + kfree(xfer.rx.buf); +} diff --git a/drivers/firmware/arm_scmi/raw_mode.h b/drivers/firmware/arm_scmi/raw_mode.h new file mode 100644 index 000000000000..8af756a83fd1 --- /dev/null +++ b/drivers/firmware/arm_scmi/raw_mode.h @@ -0,0 +1,31 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * System Control and Management Interface (SCMI) Message Protocol + * Raw mode support header. + * + * Copyright (C) 2022 ARM Ltd. + */ +#ifndef _SCMI_RAW_MODE_H +#define _SCMI_RAW_MODE_H + +#include "common.h" + +enum { + SCMI_RAW_REPLY_QUEUE, + SCMI_RAW_NOTIF_QUEUE, + SCMI_RAW_ERRS_QUEUE, + SCMI_RAW_MAX_QUEUE +}; + +void *scmi_raw_mode_init(const struct scmi_handle *handle, + struct dentry *top_dentry, int instance_id, + u8 *channels, int num_chans, + const struct scmi_desc *desc, int tx_max_msg); +void scmi_raw_mode_cleanup(void *raw); + +void scmi_raw_message_report(void *raw, struct scmi_xfer *xfer, + unsigned int idx, unsigned int chan_id); +void scmi_raw_error_report(void *raw, struct scmi_chan_info *cinfo, + u32 msg_hdr, void *priv); + +#endif /* _SCMI_RAW_MODE_H */ diff --git a/drivers/firmware/arm_scmi/smc.c b/drivers/firmware/arm_scmi/smc.c index 87a7b13cf868..93272e4bbd12 100644 --- a/drivers/firmware/arm_scmi/smc.c +++ b/drivers/firmware/arm_scmi/smc.c @@ -52,9 +52,9 @@ static irqreturn_t smc_msg_done_isr(int irq, void *data) return IRQ_HANDLED; } -static bool smc_chan_available(struct device *dev, int idx) +static bool smc_chan_available(struct device_node *of_node, int idx) { - struct device_node *np = of_parse_phandle(dev->of_node, "shmem", 0); + struct device_node *np = of_parse_phandle(of_node, "shmem", 0); if (!np) return false; @@ -171,8 +171,6 @@ static int smc_chan_free(int id, void *p, void *data) cinfo->transport_info = NULL; scmi_info->cinfo = NULL; - scmi_free_channel(cinfo, data, id); - return 0; } diff --git a/drivers/firmware/arm_scmi/virtio.c b/drivers/firmware/arm_scmi/virtio.c index 1db975c08896..d68c01cb7aa0 100644 --- a/drivers/firmware/arm_scmi/virtio.c +++ b/drivers/firmware/arm_scmi/virtio.c @@ -385,7 +385,7 @@ static int virtio_link_supplier(struct device *dev) return 0; } -static bool virtio_chan_available(struct device *dev, int idx) +static bool virtio_chan_available(struct device_node *of_node, int idx) { struct scmi_vio_channel *channels, *vioch = NULL; @@ -489,8 +489,6 @@ static int virtio_chan_free(int id, void *p, void *data) virtio_break_device(vioch->vqueue->vdev); scmi_vio_channel_cleanup_sync(vioch); - scmi_free_channel(cinfo, data, id); - return 0; } |