diff options
Diffstat (limited to 'drivers/firmware/arm_scmi/base.c')
| -rw-r--r-- | drivers/firmware/arm_scmi/base.c | 253 |
1 files changed, 253 insertions, 0 deletions
diff --git a/drivers/firmware/arm_scmi/base.c b/drivers/firmware/arm_scmi/base.c new file mode 100644 index 000000000000..0d3806c0d432 --- /dev/null +++ b/drivers/firmware/arm_scmi/base.c @@ -0,0 +1,253 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * System Control and Management Interface (SCMI) Base Protocol + * + * Copyright (C) 2018 ARM Ltd. + */ + +#include "common.h" + +enum scmi_base_protocol_cmd { + BASE_DISCOVER_VENDOR = 0x3, + BASE_DISCOVER_SUB_VENDOR = 0x4, + BASE_DISCOVER_IMPLEMENT_VERSION = 0x5, + BASE_DISCOVER_LIST_PROTOCOLS = 0x6, + BASE_DISCOVER_AGENT = 0x7, + BASE_NOTIFY_ERRORS = 0x8, +}; + +struct scmi_msg_resp_base_attributes { + u8 num_protocols; + u8 num_agents; + __le16 reserved; +}; + +/** + * scmi_base_attributes_get() - gets the implementation details + * that are associated with the base protocol. + * + * @handle - SCMI entity handle + * + * Return: 0 on success, else appropriate SCMI error. + */ +static int scmi_base_attributes_get(const struct scmi_handle *handle) +{ + int ret; + struct scmi_xfer *t; + struct scmi_msg_resp_base_attributes *attr_info; + struct scmi_revision_info *rev = handle->version; + + ret = scmi_one_xfer_init(handle, PROTOCOL_ATTRIBUTES, + SCMI_PROTOCOL_BASE, 0, sizeof(*attr_info), &t); + if (ret) + return ret; + + ret = scmi_do_xfer(handle, t); + if (!ret) { + attr_info = t->rx.buf; + rev->num_protocols = attr_info->num_protocols; + rev->num_agents = attr_info->num_agents; + } + + scmi_one_xfer_put(handle, t); + return ret; +} + +/** + * scmi_base_vendor_id_get() - gets vendor/subvendor identifier ASCII string. + * + * @handle - SCMI entity handle + * @sub_vendor - specify true if sub-vendor ID is needed + * + * Return: 0 on success, else appropriate SCMI error. + */ +static int +scmi_base_vendor_id_get(const struct scmi_handle *handle, bool sub_vendor) +{ + u8 cmd; + int ret, size; + char *vendor_id; + struct scmi_xfer *t; + struct scmi_revision_info *rev = handle->version; + + if (sub_vendor) { + cmd = BASE_DISCOVER_SUB_VENDOR; + vendor_id = rev->sub_vendor_id; + size = ARRAY_SIZE(rev->sub_vendor_id); + } else { + cmd = BASE_DISCOVER_VENDOR; + vendor_id = rev->vendor_id; + size = ARRAY_SIZE(rev->vendor_id); + } + + ret = scmi_one_xfer_init(handle, cmd, SCMI_PROTOCOL_BASE, 0, size, &t); + if (ret) + return ret; + + ret = scmi_do_xfer(handle, t); + if (!ret) + memcpy(vendor_id, t->rx.buf, size); + + scmi_one_xfer_put(handle, t); + return ret; +} + +/** + * scmi_base_implementation_version_get() - gets a vendor-specific + * implementation 32-bit version. The format of the version number is + * vendor-specific + * + * @handle - SCMI entity handle + * + * Return: 0 on success, else appropriate SCMI error. + */ +static int +scmi_base_implementation_version_get(const struct scmi_handle *handle) +{ + int ret; + __le32 *impl_ver; + struct scmi_xfer *t; + struct scmi_revision_info *rev = handle->version; + + ret = scmi_one_xfer_init(handle, BASE_DISCOVER_IMPLEMENT_VERSION, + SCMI_PROTOCOL_BASE, 0, sizeof(*impl_ver), &t); + if (ret) + return ret; + + ret = scmi_do_xfer(handle, t); + if (!ret) { + impl_ver = t->rx.buf; + rev->impl_ver = le32_to_cpu(*impl_ver); + } + + scmi_one_xfer_put(handle, t); + return ret; +} + +/** + * scmi_base_implementation_list_get() - gets the list of protocols it is + * OSPM is allowed to access + * + * @handle - SCMI entity handle + * @protocols_imp - pointer to hold the list of protocol identifiers + * + * Return: 0 on success, else appropriate SCMI error. + */ +static int scmi_base_implementation_list_get(const struct scmi_handle *handle, + u8 *protocols_imp) +{ + u8 *list; + int ret, loop; + struct scmi_xfer *t; + __le32 *num_skip, *num_ret; + u32 tot_num_ret = 0, loop_num_ret; + struct device *dev = handle->dev; + + ret = scmi_one_xfer_init(handle, BASE_DISCOVER_LIST_PROTOCOLS, + SCMI_PROTOCOL_BASE, sizeof(*num_skip), 0, &t); + if (ret) + return ret; + + num_skip = t->tx.buf; + num_ret = t->rx.buf; + list = t->rx.buf + sizeof(*num_ret); + + do { + /* Set the number of protocols to be skipped/already read */ + *num_skip = cpu_to_le32(tot_num_ret); + + ret = scmi_do_xfer(handle, t); + if (ret) + break; + + loop_num_ret = le32_to_cpu(*num_ret); + if (tot_num_ret + loop_num_ret > MAX_PROTOCOLS_IMP) { + dev_err(dev, "No. of Protocol > MAX_PROTOCOLS_IMP"); + break; + } + + for (loop = 0; loop < loop_num_ret; loop++) + protocols_imp[tot_num_ret + loop] = *(list + loop); + + tot_num_ret += loop_num_ret; + } while (loop_num_ret); + + scmi_one_xfer_put(handle, t); + return ret; +} + +/** + * scmi_base_discover_agent_get() - discover the name of an agent + * + * @handle - SCMI entity handle + * @id - Agent identifier + * @name - Agent identifier ASCII string + * + * An agent id of 0 is reserved to identify the platform itself. + * Generally operating system is represented as "OSPM" + * + * Return: 0 on success, else appropriate SCMI error. + */ +static int scmi_base_discover_agent_get(const struct scmi_handle *handle, + int id, char *name) +{ + int ret; + struct scmi_xfer *t; + + ret = scmi_one_xfer_init(handle, BASE_DISCOVER_AGENT, + SCMI_PROTOCOL_BASE, sizeof(__le32), + SCMI_MAX_STR_SIZE, &t); + if (ret) + return ret; + + *(__le32 *)t->tx.buf = cpu_to_le32(id); + + ret = scmi_do_xfer(handle, t); + if (!ret) + memcpy(name, t->rx.buf, SCMI_MAX_STR_SIZE); + + scmi_one_xfer_put(handle, t); + return ret; +} + +int scmi_base_protocol_init(struct scmi_handle *h) +{ + int id, ret; + u8 *prot_imp; + u32 version; + char name[SCMI_MAX_STR_SIZE]; + const struct scmi_handle *handle = h; + struct device *dev = handle->dev; + struct scmi_revision_info *rev = handle->version; + + ret = scmi_version_get(handle, SCMI_PROTOCOL_BASE, &version); + if (ret) + return ret; + + prot_imp = devm_kcalloc(dev, MAX_PROTOCOLS_IMP, sizeof(u8), GFP_KERNEL); + if (!prot_imp) + return -ENOMEM; + + rev->major_ver = PROTOCOL_REV_MAJOR(version), + rev->minor_ver = PROTOCOL_REV_MINOR(version); + + scmi_base_attributes_get(handle); + scmi_base_vendor_id_get(handle, false); + scmi_base_vendor_id_get(handle, true); + scmi_base_implementation_version_get(handle); + scmi_base_implementation_list_get(handle, prot_imp); + scmi_setup_protocol_implemented(handle, prot_imp); + + dev_info(dev, "SCMI Protocol v%d.%d '%s:%s' Firmware version 0x%x\n", + rev->major_ver, rev->minor_ver, rev->vendor_id, + rev->sub_vendor_id, rev->impl_ver); + dev_dbg(dev, "Found %d protocol(s) %d agent(s)\n", rev->num_protocols, + rev->num_agents); + + for (id = 0; id < rev->num_agents; id++) { + scmi_base_discover_agent_get(handle, id, name); + dev_dbg(dev, "Agent %d: %s\n", id, name); + } + + return 0; +} |