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authorSudeep Holla <sudeep.holla@arm.com>2022-02-07 13:53:54 +0300
committerSudeep Holla <sudeep.holla@arm.com>2022-02-07 13:53:54 +0300
commitb1a1b152321107c74e1bfeaa729582174405ab23 (patch)
treec861f4fbf344e0e28c7b40aaab7b3a1fdd935b3d /drivers/firmware/arm_scmi/optee.c
parente783362eb54cd99b2cac8b3a9aeac942e6f6ac07 (diff)
parent94d0cd1da14af0042c8ee7c2cf401dfc321c575c (diff)
downloadlinux-b1a1b152321107c74e1bfeaa729582174405ab23.tar.xz
Merge tag 'scmi-updates-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux into for-next/scmi
Arm SCMI firmware interface updates for v5.17 Couple of main additions: - Support for OPTEE based SCMI transport to enable using SCMI service provided by OPTEE on some platforms - Support for atomic SCMI transports which enables few SCMI transactions to be completed in atomic context. This involves other refactoring work associated with it. It also marks SMC and OPTEE as atomic transport as the commands are completed once the return Other changes involves some trace and log enhancements and a miscellaneous bug fix. * tag 'scmi-updates-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux: firmware: arm_scmi: Add new parameter to mark_txdone firmware: arm_scmi: Add atomic mode support to smc transport firmware: arm_scmi: Add support for atomic transports firmware: arm_scmi: Make optee support sync_cmds_completed_on_ret firmware: arm_scmi: Make smc support sync_cmds_completed_on_ret firmware: arm_scmi: Add sync_cmds_completed_on_ret transport flag firmware: arm_scmi: Make smc transport use common completions firmware: arm_scmi: Add configurable polling mode for transports firmware: arm_scmi: Use new trace event scmi_xfer_response_wait include: trace: Add new scmi_xfer_response_wait event firmware: arm_scmi: Refactor message response path firmware: arm_scmi: Set polling timeout to max_rx_timeout_ms firmware: arm_scmi: Perform earlier cinfo lookup call in do_xfer firmware: arm_scmi: optee: Drop the support for the OPTEE shared dynamic buffer firmware: arm_scmi: optee: Fix missing mutex_init() firmware: arm_scmi: Make virtio Version_1 compliance optional firmware: arm_scmi: Add optee transport dt-bindings: arm: Add OP-TEE transport for SCMI firmware: arm_scmi: Review some virtio log messages
Diffstat (limited to 'drivers/firmware/arm_scmi/optee.c')
-rw-r--r--drivers/firmware/arm_scmi/optee.c567
1 files changed, 567 insertions, 0 deletions
diff --git a/drivers/firmware/arm_scmi/optee.c b/drivers/firmware/arm_scmi/optee.c
new file mode 100644
index 000000000000..734f1eeee161
--- /dev/null
+++ b/drivers/firmware/arm_scmi/optee.c
@@ -0,0 +1,567 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019-2021 Linaro Ltd.
+ */
+
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/tee_drv.h>
+#include <linux/uuid.h>
+#include <uapi/linux/tee.h>
+
+#include "common.h"
+
+#define SCMI_OPTEE_MAX_MSG_SIZE 128
+
+enum scmi_optee_pta_cmd {
+ /*
+ * PTA_SCMI_CMD_CAPABILITIES - Get channel capabilities
+ *
+ * [out] value[0].a: Capability bit mask (enum pta_scmi_caps)
+ * [out] value[0].b: Extended capabilities or 0
+ */
+ PTA_SCMI_CMD_CAPABILITIES = 0,
+
+ /*
+ * PTA_SCMI_CMD_PROCESS_SMT_CHANNEL - Process SCMI message in SMT buffer
+ *
+ * [in] value[0].a: Channel handle
+ *
+ * Shared memory used for SCMI message/response exhange is expected
+ * already identified and bound to channel handle in both SCMI agent
+ * and SCMI server (OP-TEE) parts.
+ * The memory uses SMT header to carry SCMI meta-data (protocol ID and
+ * protocol message ID).
+ */
+ PTA_SCMI_CMD_PROCESS_SMT_CHANNEL = 1,
+
+ /*
+ * PTA_SCMI_CMD_PROCESS_SMT_CHANNEL_MESSAGE - Process SMT/SCMI message
+ *
+ * [in] value[0].a: Channel handle
+ * [in/out] memref[1]: Message/response buffer (SMT and SCMI payload)
+ *
+ * Shared memory used for SCMI message/response is a SMT buffer
+ * referenced by param[1]. It shall be 128 bytes large to fit response
+ * payload whatever message playload size.
+ * The memory uses SMT header to carry SCMI meta-data (protocol ID and
+ * protocol message ID).
+ */
+ PTA_SCMI_CMD_PROCESS_SMT_CHANNEL_MESSAGE = 2,
+
+ /*
+ * PTA_SCMI_CMD_GET_CHANNEL - Get channel handle
+ *
+ * SCMI shm information are 0 if agent expects to use OP-TEE regular SHM
+ *
+ * [in] value[0].a: Channel identifier
+ * [out] value[0].a: Returned channel handle
+ * [in] value[0].b: Requested capabilities mask (enum pta_scmi_caps)
+ */
+ PTA_SCMI_CMD_GET_CHANNEL = 3,
+};
+
+/*
+ * OP-TEE SCMI service capabilities bit flags (32bit)
+ *
+ * PTA_SCMI_CAPS_SMT_HEADER
+ * When set, OP-TEE supports command using SMT header protocol (SCMI shmem) in
+ * shared memory buffers to carry SCMI protocol synchronisation information.
+ */
+#define PTA_SCMI_CAPS_NONE 0
+#define PTA_SCMI_CAPS_SMT_HEADER BIT(0)
+
+/**
+ * struct scmi_optee_channel - Description of an OP-TEE SCMI channel
+ *
+ * @channel_id: OP-TEE channel ID used for this transport
+ * @tee_session: TEE session identifier
+ * @caps: OP-TEE SCMI channel capabilities
+ * @mu: Mutex protection on channel access
+ * @cinfo: SCMI channel information
+ * @shmem: Virtual base address of the shared memory
+ * @tee_shm: Reference to TEE shared memory or NULL if using static shmem
+ * @link: Reference in agent's channel list
+ */
+struct scmi_optee_channel {
+ u32 channel_id;
+ u32 tee_session;
+ u32 caps;
+ struct mutex mu;
+ struct scmi_chan_info *cinfo;
+ struct scmi_shared_mem __iomem *shmem;
+ struct tee_shm *tee_shm;
+ struct list_head link;
+};
+
+/**
+ * struct scmi_optee_agent - OP-TEE transport private data
+ *
+ * @dev: Device used for communication with TEE
+ * @tee_ctx: TEE context used for communication
+ * @caps: Supported channel capabilities
+ * @mu: Mutex for protection of @channel_list
+ * @channel_list: List of all created channels for the agent
+ */
+struct scmi_optee_agent {
+ struct device *dev;
+ struct tee_context *tee_ctx;
+ u32 caps;
+ struct mutex mu;
+ struct list_head channel_list;
+};
+
+/* There can be only 1 SCMI service in OP-TEE we connect to */
+static struct scmi_optee_agent *scmi_optee_private;
+
+/* Forward reference to scmi_optee transport initialization */
+static int scmi_optee_init(void);
+
+/* Open a session toward SCMI OP-TEE service with REE_KERNEL identity */
+static int open_session(struct scmi_optee_agent *agent, u32 *tee_session)
+{
+ struct device *dev = agent->dev;
+ struct tee_client_device *scmi_pta = to_tee_client_device(dev);
+ struct tee_ioctl_open_session_arg arg = { };
+ int ret;
+
+ memcpy(arg.uuid, scmi_pta->id.uuid.b, TEE_IOCTL_UUID_LEN);
+ arg.clnt_login = TEE_IOCTL_LOGIN_REE_KERNEL;
+
+ ret = tee_client_open_session(agent->tee_ctx, &arg, NULL);
+ if (ret < 0 || arg.ret) {
+ dev_err(dev, "Can't open tee session: %d / %#x\n", ret, arg.ret);
+ return -EOPNOTSUPP;
+ }
+
+ *tee_session = arg.session;
+
+ return 0;
+}
+
+static void close_session(struct scmi_optee_agent *agent, u32 tee_session)
+{
+ tee_client_close_session(agent->tee_ctx, tee_session);
+}
+
+static int get_capabilities(struct scmi_optee_agent *agent)
+{
+ struct tee_ioctl_invoke_arg arg = { };
+ struct tee_param param[1] = { };
+ u32 caps;
+ u32 tee_session;
+ int ret;
+
+ ret = open_session(agent, &tee_session);
+ if (ret)
+ return ret;
+
+ arg.func = PTA_SCMI_CMD_CAPABILITIES;
+ arg.session = tee_session;
+ arg.num_params = 1;
+
+ param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT;
+
+ ret = tee_client_invoke_func(agent->tee_ctx, &arg, param);
+
+ close_session(agent, tee_session);
+
+ if (ret < 0 || arg.ret) {
+ dev_err(agent->dev, "Can't get capabilities: %d / %#x\n", ret, arg.ret);
+ return -EOPNOTSUPP;
+ }
+
+ caps = param[0].u.value.a;
+
+ if (!(caps & PTA_SCMI_CAPS_SMT_HEADER)) {
+ dev_err(agent->dev, "OP-TEE SCMI PTA doesn't support SMT\n");
+ return -EOPNOTSUPP;
+ }
+
+ agent->caps = caps;
+
+ return 0;
+}
+
+static int get_channel(struct scmi_optee_channel *channel)
+{
+ struct device *dev = scmi_optee_private->dev;
+ struct tee_ioctl_invoke_arg arg = { };
+ struct tee_param param[1] = { };
+ unsigned int caps = PTA_SCMI_CAPS_SMT_HEADER;
+ int ret;
+
+ arg.func = PTA_SCMI_CMD_GET_CHANNEL;
+ arg.session = channel->tee_session;
+ arg.num_params = 1;
+
+ param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT;
+ param[0].u.value.a = channel->channel_id;
+ param[0].u.value.b = caps;
+
+ ret = tee_client_invoke_func(scmi_optee_private->tee_ctx, &arg, param);
+
+ if (ret || arg.ret) {
+ dev_err(dev, "Can't get channel with caps %#x: %d / %#x\n", caps, ret, arg.ret);
+ return -EOPNOTSUPP;
+ }
+
+ /* From now on use channel identifer provided by OP-TEE SCMI service */
+ channel->channel_id = param[0].u.value.a;
+ channel->caps = caps;
+
+ return 0;
+}
+
+static int invoke_process_smt_channel(struct scmi_optee_channel *channel)
+{
+ struct tee_ioctl_invoke_arg arg = { };
+ struct tee_param param[2] = { };
+ int ret;
+
+ arg.session = channel->tee_session;
+ param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT;
+ param[0].u.value.a = channel->channel_id;
+
+ if (channel->tee_shm) {
+ param[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT;
+ param[1].u.memref.shm = channel->tee_shm;
+ param[1].u.memref.size = SCMI_OPTEE_MAX_MSG_SIZE;
+ arg.num_params = 2;
+ arg.func = PTA_SCMI_CMD_PROCESS_SMT_CHANNEL_MESSAGE;
+ } else {
+ arg.num_params = 1;
+ arg.func = PTA_SCMI_CMD_PROCESS_SMT_CHANNEL;
+ }
+
+ ret = tee_client_invoke_func(scmi_optee_private->tee_ctx, &arg, param);
+ if (ret < 0 || arg.ret) {
+ dev_err(scmi_optee_private->dev, "Can't invoke channel %u: %d / %#x\n",
+ channel->channel_id, ret, arg.ret);
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static int scmi_optee_link_supplier(struct device *dev)
+{
+ if (!scmi_optee_private) {
+ if (scmi_optee_init())
+ dev_dbg(dev, "Optee bus not yet ready\n");
+
+ /* Wait for optee bus */
+ return -EPROBE_DEFER;
+ }
+
+ if (!device_link_add(dev, scmi_optee_private->dev, DL_FLAG_AUTOREMOVE_CONSUMER)) {
+ dev_err(dev, "Adding link to supplier optee device failed\n");
+ return -ECANCELED;
+ }
+
+ return 0;
+}
+
+static bool scmi_optee_chan_available(struct device *dev, int idx)
+{
+ u32 channel_id;
+
+ return !of_property_read_u32_index(dev->of_node, "linaro,optee-channel-id",
+ idx, &channel_id);
+}
+
+static void scmi_optee_clear_channel(struct scmi_chan_info *cinfo)
+{
+ struct scmi_optee_channel *channel = cinfo->transport_info;
+
+ shmem_clear_channel(channel->shmem);
+}
+
+static int setup_static_shmem(struct device *dev, struct scmi_chan_info *cinfo,
+ struct scmi_optee_channel *channel)
+{
+ struct device_node *np;
+ resource_size_t size;
+ struct resource res;
+ int ret;
+
+ np = of_parse_phandle(cinfo->dev->of_node, "shmem", 0);
+ if (!of_device_is_compatible(np, "arm,scmi-shmem")) {
+ ret = -ENXIO;
+ goto out;
+ }
+
+ ret = of_address_to_resource(np, 0, &res);
+ if (ret) {
+ dev_err(dev, "Failed to get SCMI Tx shared memory\n");
+ goto out;
+ }
+
+ size = resource_size(&res);
+
+ channel->shmem = devm_ioremap(dev, res.start, size);
+ if (!channel->shmem) {
+ dev_err(dev, "Failed to ioremap SCMI Tx shared memory\n");
+ ret = -EADDRNOTAVAIL;
+ goto out;
+ }
+
+ ret = 0;
+
+out:
+ of_node_put(np);
+
+ return ret;
+}
+
+static int setup_shmem(struct device *dev, struct scmi_chan_info *cinfo,
+ struct scmi_optee_channel *channel)
+{
+ if (of_find_property(cinfo->dev->of_node, "shmem", NULL))
+ return setup_static_shmem(dev, cinfo, channel);
+ else
+ return -ENOMEM;
+}
+
+static int scmi_optee_chan_setup(struct scmi_chan_info *cinfo, struct device *dev, bool tx)
+{
+ struct scmi_optee_channel *channel;
+ uint32_t channel_id;
+ int ret;
+
+ if (!tx)
+ return -ENODEV;
+
+ channel = devm_kzalloc(dev, sizeof(*channel), GFP_KERNEL);
+ if (!channel)
+ return -ENOMEM;
+
+ ret = of_property_read_u32_index(cinfo->dev->of_node, "linaro,optee-channel-id",
+ 0, &channel_id);
+ if (ret)
+ return ret;
+
+ cinfo->transport_info = channel;
+ channel->cinfo = cinfo;
+ channel->channel_id = channel_id;
+ mutex_init(&channel->mu);
+
+ ret = setup_shmem(dev, cinfo, channel);
+ if (ret)
+ return ret;
+
+ ret = open_session(scmi_optee_private, &channel->tee_session);
+ if (ret)
+ goto err_free_shm;
+
+ ret = get_channel(channel);
+ if (ret)
+ goto err_close_sess;
+
+ /* Enable polling */
+ cinfo->no_completion_irq = true;
+
+ mutex_lock(&scmi_optee_private->mu);
+ list_add(&channel->link, &scmi_optee_private->channel_list);
+ mutex_unlock(&scmi_optee_private->mu);
+
+ return 0;
+
+err_close_sess:
+ close_session(scmi_optee_private, channel->tee_session);
+err_free_shm:
+ if (channel->tee_shm)
+ tee_shm_free(channel->tee_shm);
+
+ return ret;
+}
+
+static int scmi_optee_chan_free(int id, void *p, void *data)
+{
+ struct scmi_chan_info *cinfo = p;
+ struct scmi_optee_channel *channel = cinfo->transport_info;
+
+ mutex_lock(&scmi_optee_private->mu);
+ list_del(&channel->link);
+ mutex_unlock(&scmi_optee_private->mu);
+
+ close_session(scmi_optee_private, channel->tee_session);
+
+ if (channel->tee_shm) {
+ tee_shm_free(channel->tee_shm);
+ channel->tee_shm = NULL;
+ }
+
+ cinfo->transport_info = NULL;
+ channel->cinfo = NULL;
+
+ scmi_free_channel(cinfo, data, id);
+
+ return 0;
+}
+
+static struct scmi_shared_mem *get_channel_shm(struct scmi_optee_channel *chan,
+ struct scmi_xfer *xfer)
+{
+ if (!chan)
+ return NULL;
+
+ return chan->shmem;
+}
+
+
+static int scmi_optee_send_message(struct scmi_chan_info *cinfo,
+ struct scmi_xfer *xfer)
+{
+ struct scmi_optee_channel *channel = cinfo->transport_info;
+ struct scmi_shared_mem *shmem = get_channel_shm(channel, xfer);
+ int ret;
+
+ mutex_lock(&channel->mu);
+ shmem_tx_prepare(shmem, xfer);
+
+ ret = invoke_process_smt_channel(channel);
+ if (ret)
+ mutex_unlock(&channel->mu);
+
+ return ret;
+}
+
+static void scmi_optee_fetch_response(struct scmi_chan_info *cinfo,
+ struct scmi_xfer *xfer)
+{
+ struct scmi_optee_channel *channel = cinfo->transport_info;
+ struct scmi_shared_mem *shmem = get_channel_shm(channel, xfer);
+
+ shmem_fetch_response(shmem, xfer);
+}
+
+static void scmi_optee_mark_txdone(struct scmi_chan_info *cinfo, int ret,
+ struct scmi_xfer *__unused)
+{
+ struct scmi_optee_channel *channel = cinfo->transport_info;
+
+ mutex_unlock(&channel->mu);
+}
+
+static struct scmi_transport_ops scmi_optee_ops = {
+ .link_supplier = scmi_optee_link_supplier,
+ .chan_available = scmi_optee_chan_available,
+ .chan_setup = scmi_optee_chan_setup,
+ .chan_free = scmi_optee_chan_free,
+ .send_message = scmi_optee_send_message,
+ .mark_txdone = scmi_optee_mark_txdone,
+ .fetch_response = scmi_optee_fetch_response,
+ .clear_channel = scmi_optee_clear_channel,
+};
+
+static int scmi_optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
+{
+ return ver->impl_id == TEE_IMPL_ID_OPTEE;
+}
+
+static int scmi_optee_service_probe(struct device *dev)
+{
+ struct scmi_optee_agent *agent;
+ struct tee_context *tee_ctx;
+ int ret;
+
+ /* Only one SCMI OP-TEE device allowed */
+ if (scmi_optee_private) {
+ dev_err(dev, "An SCMI OP-TEE device was already initialized: only one allowed\n");
+ return -EBUSY;
+ }
+
+ tee_ctx = tee_client_open_context(NULL, scmi_optee_ctx_match, NULL, NULL);
+ if (IS_ERR(tee_ctx))
+ return -ENODEV;
+
+ agent = devm_kzalloc(dev, sizeof(*agent), GFP_KERNEL);
+ if (!agent) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ agent->dev = dev;
+ agent->tee_ctx = tee_ctx;
+ INIT_LIST_HEAD(&agent->channel_list);
+ mutex_init(&agent->mu);
+
+ ret = get_capabilities(agent);
+ if (ret)
+ goto err;
+
+ /* Ensure agent resources are all visible before scmi_optee_private is */
+ smp_mb();
+ scmi_optee_private = agent;
+
+ return 0;
+
+err:
+ tee_client_close_context(tee_ctx);
+
+ return ret;
+}
+
+static int scmi_optee_service_remove(struct device *dev)
+{
+ struct scmi_optee_agent *agent = scmi_optee_private;
+
+ if (!scmi_optee_private)
+ return -EINVAL;
+
+ if (!list_empty(&scmi_optee_private->channel_list))
+ return -EBUSY;
+
+ /* Ensure cleared reference is visible before resources are released */
+ smp_store_mb(scmi_optee_private, NULL);
+
+ tee_client_close_context(agent->tee_ctx);
+
+ return 0;
+}
+
+static const struct tee_client_device_id scmi_optee_service_id[] = {
+ {
+ UUID_INIT(0xa8cfe406, 0xd4f5, 0x4a2e,
+ 0x9f, 0x8d, 0xa2, 0x5d, 0xc7, 0x54, 0xc0, 0x99)
+ },
+ { }
+};
+
+MODULE_DEVICE_TABLE(tee, scmi_optee_service_id);
+
+static struct tee_client_driver scmi_optee_driver = {
+ .id_table = scmi_optee_service_id,
+ .driver = {
+ .name = "scmi-optee",
+ .bus = &tee_bus_type,
+ .probe = scmi_optee_service_probe,
+ .remove = scmi_optee_service_remove,
+ },
+};
+
+static int scmi_optee_init(void)
+{
+ return driver_register(&scmi_optee_driver.driver);
+}
+
+static void scmi_optee_exit(void)
+{
+ if (scmi_optee_private)
+ driver_unregister(&scmi_optee_driver.driver);
+}
+
+const struct scmi_desc scmi_optee_desc = {
+ .transport_exit = scmi_optee_exit,
+ .ops = &scmi_optee_ops,
+ .max_rx_timeout_ms = 30,
+ .max_msg = 20,
+ .max_msg_size = SCMI_OPTEE_MAX_MSG_SIZE,
+ .sync_cmds_completed_on_ret = true,
+};