Add a remoteproc TEE (Trusted Execution Environment) driver that will be probed by the TEE bus. If the associated Trusted application is supported on the secure part, this driver offers a client interface to load firmware by the secure part. This firmware could be authenticated by the secure trusted application.

A specificity of the implementation is that the firmware has to be authenticated and optionally decrypted to access the resource table.

Consequently, the boot sequence is:

1) rproc_parse_fw --> rproc_tee_parse_fw remoteproc TEE: - Requests the TEE application to authenticate and load the firmware in the remote processor memories. - Requests the TEE application for the address of the resource table. - Creates a copy of the resource table stored in rproc->cached_table.

2) rproc_load_segments --> rproc_tee_load_fw remoteproc TEE: - Requests the TEE application to load the firmware. Nothing is done at the TEE application as the firmware is already loaded. - In case of recovery, the TEE application has to reload the firmware.

3) rproc_tee_get_loaded_rsc_table remoteproc TEE requests the TEE application for the address of the resource table.

4) rproc_start --> rproc_tee_start - Requests the TEE application to start the remote processor.

The shutdown sequence is:

5) rproc_stop --> rproc_tee_stop - Requests the TEE application to stop the remote processor.

6) rproc_tee_release_fw This function is used to request the TEE application to perform actions to return to the initial state on stop or on error during the boot sequence.

Signed-off-by: Arnaud Pouliquen arnaud.pouliquen@foss.st.com --- Updates vs previous version: - Come back to v13 managing a load in rproc_tee_parse_fw(). - Replace IS_REACHABLE with IS_ENABLED in remoteproc_tee.h, remoteproc_tee is not supported as module - update REMOTEPROC_TEE config description in Kconfig - manage unbind sequence of the consumer rproc drivers using devlink - remove TA_RPROC_FW_CMD_GET_COREDUMP as not use ( to be treated in a separate thread) - define a static `rproc_tee_ctx` variable instead of allocating it - add spinlock to protect `rproc_tee_ctx` accesses. - add exported function doumentation --- drivers/remoteproc/Kconfig | 10 + drivers/remoteproc/Makefile | 1 + drivers/remoteproc/remoteproc_tee.c | 619 ++++++++++++++++++++++++++++ include/linux/remoteproc_tee.h | 90 ++++ 4 files changed, 720 insertions(+) create mode 100644 drivers/remoteproc/remoteproc_tee.c create mode 100644 include/linux/remoteproc_tee.h

diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig index 83962a114dc9..e39265d249d9 100644 --- a/drivers/remoteproc/Kconfig +++ b/drivers/remoteproc/Kconfig @@ -23,6 +23,16 @@ config REMOTEPROC_CDEV

It's safe to say N if you don't want to use this interface.

+config REMOTEPROC_TEE + bool "Remoteproc support by a TEE application" + depends on OPTEE + help + Support a remote processor that is managed by an application running in a Trusted + Execution Environment (TEE). This application is responsible for loading the remote + processor firmware image and managing its lifecycle. + + It's safe to say N if the remote processor is not managed by a TEE. + config IMX_REMOTEPROC tristate "i.MX remoteproc support" depends on ARCH_MXC diff --git a/drivers/remoteproc/Makefile b/drivers/remoteproc/Makefile index 5ff4e2fee4ab..f77e0abe8349 100644 --- a/drivers/remoteproc/Makefile +++ b/drivers/remoteproc/Makefile @@ -11,6 +11,7 @@ remoteproc-y += remoteproc_sysfs.o remoteproc-y += remoteproc_virtio.o remoteproc-y += remoteproc_elf_loader.o obj-$(CONFIG_REMOTEPROC_CDEV) += remoteproc_cdev.o +obj-$(CONFIG_REMOTEPROC_TEE) += remoteproc_tee.o obj-$(CONFIG_IMX_REMOTEPROC) += imx_rproc.o obj-$(CONFIG_IMX_DSP_REMOTEPROC) += imx_dsp_rproc.o obj-$(CONFIG_INGENIC_VPU_RPROC) += ingenic_rproc.o diff --git a/drivers/remoteproc/remoteproc_tee.c b/drivers/remoteproc/remoteproc_tee.c new file mode 100644 index 000000000000..cf50de7eb952 --- /dev/null +++ b/drivers/remoteproc/remoteproc_tee.c @@ -0,0 +1,619 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) STMicroelectronics 2024 + * Author: Arnaud Pouliquen arnaud.pouliquen@foss.st.com + */ + +#include <linux/firmware.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/remoteproc.h> +#include <linux/remoteproc_tee.h> +#include <linux/slab.h> +#include <linux/tee_drv.h> + +#define MAX_TEE_PARAM_ARRAY_MEMBER 4 + +/* + * Authentication and load of the firmware image in the remote processor memories by the TEE. + * After this step the firmware is loaded in destination memories, which can then be locked to + * prevent access by Linux. + * + * [in] params[0].value.a: remote processor identifier + * [in] params[1].memref: buffer containing a temporary copy of the signed image to load. + */ +#define TA_RPROC_FW_CMD_LOAD_FW 1 + +/* + * Start the remote processor by the TEE + * + * [in] params[0].value.a: remote processor identifier + */ +#define TA_RPROC_FW_CMD_START 2 + +/* + * Stop the remote processor by the TEE + * + * [in] params[0].value.a: remote processor identifier + */ +#define TA_RPROC_FW_CMD_STOP 3 + +/* + * Return the address of the resource table, or 0 if not found. + * + * [in] params[0].value.a: remote processor identifier + * [out] params[1].value.a: 32bit LSB resource table memory address + * [out] params[1].value.b: 32bit MSB resource table memory address + * [out] params[2].value.a: 32bit LSB resource table memory size + * [out] params[2].value.b: 32bit MSB resource table memory size + */ +#define TA_RPROC_FW_CMD_GET_RSC_TABLE 4 + +/* + * Release remote processor firmware images and associated resources. + * This command should be used in case an error occurs between the loading of + * the firmware images (TA_RPROC_CMD_LOAD_FW) and the starting of the remote + * processor (TA_RPROC_CMD_START_FW) or after stopping the remote processor + * to release associated resources (TA_RPROC_CMD_STOP_FW). + * + * [in] params[0].value.a: Unique 32-bit remote processor identifier + */ +#define TA_RPROC_CMD_RELEASE_FW 6 + +struct rproc_tee_context { + struct list_head sessions; + struct tee_context *tee_ctx; + struct device *dev; +}; + +/** + * struct rproc_tee - TEE remoteproc structure + * @node: Reference in list + * @rproc: Remoteproc reference + * @rproc_id: Identifier of the target firmware + * @session_id: TEE session identifier + */ +struct rproc_tee { + struct list_head node; + struct rproc *rproc; + u32 rproc_id; + u32 session_id; +}; + +static struct rproc_tee_context rproc_tee_ctx; +static DEFINE_SPINLOCK(ctx_lock); + +static struct rproc_tee *rproc_to_trproc(struct rproc *rproc) +{ + struct rproc_tee *trproc; + + list_for_each_entry(trproc, &rproc_tee_ctx.sessions, node) + if (trproc->rproc == rproc) + return trproc; + + return NULL; +} + +static void rproc_tee_prepare_args(struct rproc_tee *trproc, int cmd, + struct tee_ioctl_invoke_arg *arg, + struct tee_param *param, + unsigned int num_params) +{ + memset(arg, 0, sizeof(*arg)); + memset(param, 0, MAX_TEE_PARAM_ARRAY_MEMBER * sizeof(*param)); + + arg->func = cmd; + arg->session = trproc->session_id; + arg->num_params = num_params + 1; + + param[0] = (struct tee_param) { + .attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT, + .u.value.a = trproc->rproc_id, + }; +} + +/** + * rproc_tee_release_fw - Release the firmware for a TEE-based remote processor + * + * This function invokes the TA_RPROC_CMD_RELEASE_FW TEE client function to release the firmware. + * It should only be called when the remoteproc state is RPROC_OFFLINE or RPROC_DETACHED. + * The function requests the TEE remoteproc application to release the firmware loaded by + * rproc_tee_load_fw(). The request is ignored if the rproc state is RPROC_DETACHED as the + * remote processor is still running. + * + * @rproc: Pointer to the struct rproc representing the remote processor + */ +void rproc_tee_release_fw(struct rproc *rproc) +{ + struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER]; + struct rproc_tee *trproc = rproc_to_trproc(rproc); + struct tee_ioctl_invoke_arg arg; + int ret; + + if (!rproc_tee_ctx.dev) + return; + + if (!trproc) + return; + + /* + * If the remote processor state is RPROC_DETACHED, just ignore the + * request, as the remote processor is still running. + */ + if (rproc->state == RPROC_DETACHED) + return; + + if (rproc->state != RPROC_OFFLINE) { + dev_err(rproc_tee_ctx.dev, "unexpected rproc state: %d\n", rproc->state); + return; + } + + rproc_tee_prepare_args(trproc, TA_RPROC_CMD_RELEASE_FW, &arg, param, 0); + + ret = tee_client_invoke_func(rproc_tee_ctx.tee_ctx, &arg, param); + if (ret < 0 || arg.ret != 0) { + dev_err(rproc_tee_ctx.dev, + "TA_RPROC_CMD_RELEASE_FW invoke failed TEE err: %#x, ret:%d\n", + arg.ret, ret); + ret = -EIO; + } +} +EXPORT_SYMBOL_GPL(rproc_tee_release_fw); + +/** + * rproc_tee_load_fw - Load firmware from TEE application + * @rproc: Pointer to the struct rproc representing the remote processor + * @fw: Pointer to the firmware structure containing the firmware data and size + * + * This function invokes the TA_RPROC_FW_CMD_LOAD_FW TEE client function to load the firmware. + * It registers the fw->data as a shared memory region with the TEE, and request the TEE to load + * the firmware. This function can be called twice during the remote processor boot, considering + * that the TEE application ignores the command if the firmware is already loaded. + * + * @rproc: Pointer to the struct rproc representing the remote processor + * @fw: Pointer to the firmware structure containing the firmware data and size + * + * Return: 0 on success, or an error code on failure + */ +int rproc_tee_load_fw(struct rproc *rproc, const struct firmware *fw) +{ + struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER]; + struct rproc_tee *trproc = rproc_to_trproc(rproc); + struct tee_ioctl_invoke_arg arg; + struct tee_shm *fw_shm; + int ret; + + if (!rproc_tee_ctx.dev) + return -ENODEV; + + if (!trproc) + return -EINVAL; + + fw_shm = tee_shm_register_kernel_buf(rproc_tee_ctx.tee_ctx, (void *)fw->data, fw->size); + if (IS_ERR(fw_shm)) + return PTR_ERR(fw_shm); + + rproc_tee_prepare_args(trproc, TA_RPROC_FW_CMD_LOAD_FW, &arg, param, 1); + + /* Provide the address of the firmware image */ + param[1] = (struct tee_param) { + .attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT, + .u.memref = { + .shm = fw_shm, + .size = fw->size, + .shm_offs = 0, + }, + }; + + ret = tee_client_invoke_func(rproc_tee_ctx.tee_ctx, &arg, param); + if (ret < 0 || arg.ret != 0) { + dev_err(rproc_tee_ctx.dev, + "TA_RPROC_FW_CMD_LOAD_FW invoke failed TEE err: %#x, ret:%d\n", + arg.ret, ret); + if (!ret) + ret = -EIO; + } + + tee_shm_free(fw_shm); + + return ret; +} +EXPORT_SYMBOL_GPL(rproc_tee_load_fw); + +static int rproc_tee_get_loaded_rsc_table(struct rproc *rproc, phys_addr_t *rsc_pa, + size_t *table_sz) +{ + struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER]; + struct rproc_tee *trproc = rproc_to_trproc(rproc); + struct tee_ioctl_invoke_arg arg; + int ret; + + if (!rproc_tee_ctx.dev) + return -ENODEV; + + if (!trproc) + return -EINVAL; + + rproc_tee_prepare_args(trproc, TA_RPROC_FW_CMD_GET_RSC_TABLE, &arg, param, 2); + + param[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT; + param[2].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT; + + ret = tee_client_invoke_func(rproc_tee_ctx.tee_ctx, &arg, param); + if (ret < 0 || arg.ret != 0) { + dev_err(rproc_tee_ctx.dev, + "TA_RPROC_FW_CMD_GET_RSC_TABLE invoke failed TEE err: %#x, ret:%d\n", + arg.ret, ret); + return -EIO; + } + + *table_sz = param[2].u.value.a; + + if (*table_sz) + *rsc_pa = param[1].u.value.a; + else + *rsc_pa = 0; + + return 0; +} + +/** + * rproc_tee_parse_fw - Get the resource table from TEE application + * @rproc: Pointer to the struct rproc representing the remote processor + * @fw: Pointer to the firmware structure containing the firmware data and size + * + * This function retrieves the loaded resource table and creates a cached_table copy. Since the + * firmware image is signed and potentially encrypted, the firmware must be loaded first to + * access the loaded resource table. + * + * @rproc: Pointer to the struct rproc representing the remote processor + * @fw: Pointer to the firmware structure containing the firmware data and size + * + * Return: 0 on success, or an error code on failure + */ +int rproc_tee_parse_fw(struct rproc *rproc, const struct firmware *fw) +{ + phys_addr_t rsc_table; + void __iomem *rsc_va; + size_t table_sz; + int ret; + + if (!rproc) + return -EINVAL; + + /* We need first to Load the firmware, to be able to get the resource table. */ + ret = rproc_tee_load_fw(rproc, fw); + if (ret) + return ret; + + ret = rproc_tee_get_loaded_rsc_table(rproc, &rsc_table, &table_sz); + if (ret) + goto release_fw; + + /* + * We assume here that the memory mapping is the same between the TEE and Linux kernel + * contexts. Else a new TEE remoteproc service could be needed to get a copy of the + * resource table + */ + rsc_va = ioremap_wc(rsc_table, table_sz); + if (!rsc_va) { + dev_err(rproc_tee_ctx.dev, "Unable to map memory region: %pa+%zx\n", + &rsc_table, table_sz); + ret = -ENOMEM; + goto release_fw; + } + + /* + * Create a copy of the resource table to have the same behavior as the ELF loader. + * This cached table will be used by the remoteproc core after the remoteproc stops + * to free resources and for crash recovery to reapply the settings. + * The cached table will be freed by the remoteproc core. + */ + rproc->cached_table = kmemdup((__force void *)rsc_va, table_sz, GFP_KERNEL); + iounmap(rsc_va); + + if (!rproc->cached_table) { + ret = -ENOMEM; + goto release_fw; + } + + rproc->table_ptr = rproc->cached_table; + rproc->table_sz = table_sz; + + return 0; + +release_fw: + rproc_tee_release_fw(rproc); + return ret; +} +EXPORT_SYMBOL_GPL(rproc_tee_parse_fw); + +/** + * rproc_tee_find_loaded_rsc_table - Find the loaded resource table loaded by the TEE application + * @rproc: Pointer to the struct rproc representing the remote processor + * @fw: Pointer to the firmware structure containing the firmware data and size + * + * This function retrieves the physical address and size of the resource table loaded by the TEE + * application. + * + * @rproc: Pointer to the struct rproc representing the remote processor + * @fw: Pointer to the firmware structure containing the firmware data and size + * + * Return: pointer to the resource table if found, or NULL if not found or size is 0 + */ +struct resource_table *rproc_tee_find_loaded_rsc_table(struct rproc *rproc, + const struct firmware *fw) +{ + phys_addr_t rsc_table; + size_t table_sz; + int ret; + + ret = rproc_tee_get_loaded_rsc_table(rproc, &rsc_table, &table_sz); + if (ret) + return NULL; + + rproc->table_sz = table_sz; + if (!table_sz) + return NULL; + + /* + * At this step the memory area that contains the resource table should have been registered + * by the remote proc platform driver and allocated by rproc_alloc_registered_carveouts(). + */ + return (struct resource_table *)rproc_pa_to_va(rproc, rsc_table, table_sz, NULL); +} +EXPORT_SYMBOL_GPL(rproc_tee_find_loaded_rsc_table); + +/** + * rproc_tee_start - Request the TEE application to start the remote processor + * + * This function invokes the TA_RPROC_FW_CMD_START command to start the remote processor. + * + * @rproc: Pointer to the struct rproc representing the remote processor + * + * Return: Returns 0 on success, -EINVAL or -EIO on failure + */ +int rproc_tee_start(struct rproc *rproc) +{ + struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER]; + struct rproc_tee *trproc = rproc_to_trproc(rproc); + struct tee_ioctl_invoke_arg arg; + int ret = 0; + + if (!trproc) + return -EINVAL; + + rproc_tee_prepare_args(trproc, TA_RPROC_FW_CMD_START, &arg, param, 0); + + ret = tee_client_invoke_func(rproc_tee_ctx.tee_ctx, &arg, param); + if (ret < 0 || arg.ret != 0) { + dev_err(rproc_tee_ctx.dev, + "TA_RPROC_FW_CMD_START invoke failed TEE err: %#x, ret:%d\n", arg.ret, ret); + if (!ret) + return -EIO; + } + + return 0; +} +EXPORT_SYMBOL_GPL(rproc_tee_start); + +/** + * rproc_tee_stop - Request the TEE application to start the remote processor + * + * This function invokes the TA_RPROC_FW_CMD_STOP command to stop the remote processor. + * + * @rproc: Pointer to the struct rproc representing the remote processor + * + * Return: Returns 0 on success, -EINVAL or -EIO on failure + */ +int rproc_tee_stop(struct rproc *rproc) +{ + struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER]; + struct rproc_tee *trproc = rproc_to_trproc(rproc); + struct tee_ioctl_invoke_arg arg; + int ret; + + if (!trproc) + return -EINVAL; + + rproc_tee_prepare_args(trproc, TA_RPROC_FW_CMD_STOP, &arg, param, 0); + + ret = tee_client_invoke_func(rproc_tee_ctx.tee_ctx, &arg, param); + if (ret < 0 || arg.ret != 0) { + dev_err(rproc_tee_ctx.dev, + "TA_RPROC_FW_CMD_STOP invoke failed TEE err: %#x, ret:%d\n", arg.ret, ret); + if (!ret) + ret = -EIO; + } + + return ret; +} +EXPORT_SYMBOL_GPL(rproc_tee_stop); + +static const struct tee_client_device_id rproc_tee_id_table[] = { + {UUID_INIT(0x80a4c275, 0x0a47, 0x4905, 0x82, 0x85, 0x14, 0x86, 0xa9, 0x77, 0x1a, 0x08)}, + {} +}; + +/** + * rproc_tee_register - Register a remote processor controlled by a TEE application. + * + * This function registers a remote processor that will be managed by a TEE application,by opening + * a session with the TEE client. + * + * @dev: Pointer to client rproc device + * @rproc: Pointer to the struct rproc representing the remote processor + * @rproc_id: ID of the remote processor + * + * Return: Returns 0 on success, or an error code on failure + */ +int rproc_tee_register(struct device *dev, struct rproc *rproc, unsigned int rproc_id) +{ + struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER]; + struct tee_ioctl_open_session_arg sess_arg; + struct tee_client_device *tee_device; + struct rproc_tee *trproc; + struct device_link *link; + int ret; + + spin_lock(&ctx_lock); + /* + * Test if the device has been probed by the TEE bus. In case of failure, we ignore the + * reason. The bus could be not yet probed or the service not available in the secure + * firmware.The assumption in such a case is that the TEE remoteproc is not probed. + */ + if (!rproc_tee_ctx.dev) { + ret = -EPROBE_DEFER; + goto out; + } + + trproc = kzalloc(sizeof(*trproc), GFP_KERNEL); + if (!trproc) { + ret = -ENOMEM; + goto out; + } + + tee_device = to_tee_client_device(rproc_tee_ctx.dev); + memset(&sess_arg, 0, sizeof(sess_arg)); + + memcpy(sess_arg.uuid, tee_device->id.uuid.b, TEE_IOCTL_UUID_LEN); + + sess_arg.clnt_login = TEE_IOCTL_LOGIN_REE_KERNEL; + sess_arg.num_params = 1; + + param[0] = (struct tee_param) { + .attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT, + .u.value.a = rproc_id, + }; + + ret = tee_client_open_session(rproc_tee_ctx.tee_ctx, &sess_arg, param); + if (ret < 0 || sess_arg.ret != 0) { + dev_err(dev, "tee_client_open_session failed, err: %#x\n", sess_arg.ret); + ret = -EINVAL; + goto free_tproc; + } + + trproc->rproc_id = rproc_id; + trproc->session_id = sess_arg.session; + + trproc->rproc = rproc; + + /* Create device link between the rproc device and the TEE device */ + link = device_link_add(dev, rproc_tee_ctx.dev, DL_FLAG_AUTOREMOVE_CONSUMER); + if (!link) { + ret = -ENOMEM; + goto close_tee; + } + list_add_tail(&trproc->node, &rproc_tee_ctx.sessions); + + goto out; + +close_tee: + if (tee_client_close_session(rproc_tee_ctx.tee_ctx, trproc->session_id)) + dev_err(rproc_tee_ctx.dev, "tee_client_close_session failed\n"); +free_tproc: + kfree(trproc); +out: + spin_unlock(&ctx_lock); + + return ret; +} +EXPORT_SYMBOL_GPL(rproc_tee_register); + +/** + * rproc_tee_unregister - Register a remote processor controlled by a TEE application. + * + * This function unregisters a remote processor previously registered by the rproc_tee_register() + * function. + * + * @dev: Pointer to client rproc device + * @rproc: Pointer to the struct rproc representing the remote processor + * + * Return: Returns 0 on success, or an error code on failure + */ +int rproc_tee_unregister(struct device *dev, struct rproc *rproc) +{ + struct rproc_tee *trproc = rproc_to_trproc(rproc); + int ret; + + if (!trproc) + return -EINVAL; + + spin_lock(&ctx_lock); + + ret = tee_client_close_session(rproc_tee_ctx.tee_ctx, trproc->session_id); + if (ret < 0) + dev_err(rproc_tee_ctx.dev, "tee_client_close_session failed, err: %#x\n", ret); + + spin_unlock(&ctx_lock); + + list_del(&trproc->node); + kfree(trproc); + + return ret; +} +EXPORT_SYMBOL_GPL(rproc_tee_unregister); + +static int rproc_tee_ctx_match(struct tee_ioctl_version_data *ver, const void *data) +{ + /* Today we support only the OP-TEE, could be extend to other tees */ + return (ver->impl_id == TEE_IMPL_ID_OPTEE); +} + +static int rproc_tee_probe(struct device *dev) +{ + struct tee_context *tee_ctx; + + /* Open context with TEE driver */ + tee_ctx = tee_client_open_context(NULL, rproc_tee_ctx_match, NULL, NULL); + if (IS_ERR(tee_ctx)) + return PTR_ERR(tee_ctx); + + spin_lock(&ctx_lock); + rproc_tee_ctx.dev = dev; + rproc_tee_ctx.tee_ctx = tee_ctx; + INIT_LIST_HEAD(&rproc_tee_ctx.sessions); + spin_unlock(&ctx_lock); + + return 0; +} + +static int rproc_tee_remove(struct device *dev) +{ + spin_lock(&ctx_lock); + tee_client_close_context(rproc_tee_ctx.tee_ctx); + rproc_tee_ctx.dev = NULL; + rproc_tee_ctx.tee_ctx = NULL; + spin_unlock(&ctx_lock); + + return 0; +} + +MODULE_DEVICE_TABLE(tee, rproc_tee_id_table); + +static struct tee_client_driver rproc_tee_fw_driver = { + .id_table = rproc_tee_id_table, + .driver = { + .name = KBUILD_MODNAME, + .bus = &tee_bus_type, + .probe = rproc_tee_probe, + .remove = rproc_tee_remove, + }, +}; + +static int __init rproc_tee_fw_mod_init(void) +{ + return driver_register(&rproc_tee_fw_driver.driver); +} + +static void __exit rproc_tee_fw_mod_exit(void) +{ + driver_unregister(&rproc_tee_fw_driver.driver); +} + +module_init(rproc_tee_fw_mod_init); +module_exit(rproc_tee_fw_mod_exit); + +MODULE_DESCRIPTION(" remote processor TEE module"); +MODULE_LICENSE("GPL"); diff --git a/include/linux/remoteproc_tee.h b/include/linux/remoteproc_tee.h new file mode 100644 index 000000000000..659bd77a4f12 --- /dev/null +++ b/include/linux/remoteproc_tee.h @@ -0,0 +1,90 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright(c) 2024 STMicroelectronics + */ + +#ifndef REMOTEPROC_TEE_H +#define REMOTEPROC_TEE_H + +#include <linux/tee_drv.h> +#include <linux/firmware.h> +#include <linux/remoteproc.h> + +struct rproc; +struct rproc_tee; + +#if IS_ENABLED(CONFIG_REMOTEPROC_TEE) + +int rproc_tee_register(struct device *dev, struct rproc *rproc, unsigned int rproc_id); +int rproc_tee_unregister(struct device *dev, struct rproc *rproc); +int rproc_tee_parse_fw(struct rproc *rproc, const struct firmware *fw); +int rproc_tee_load_fw(struct rproc *rproc, const struct firmware *fw); +void rproc_tee_release_fw(struct rproc *rproc); +struct resource_table *rproc_tee_find_loaded_rsc_table(struct rproc *rproc, + const struct firmware *fw); +int rproc_tee_start(struct rproc *rproc); +int rproc_tee_stop(struct rproc *rproc); + +#else + +static inline int rproc_tee_register(struct device *dev, struct rproc *rproc, unsigned int rproc_id) +{ + return -ENODEV; +} + +static inline int rproc_tee_parse_fw(struct rproc *rproc, const struct firmware *fw) +{ + /* This shouldn't be possible */ + WARN_ON(1); + + return 0; +} + +static inline int rproc_tee_unregister(struct device *dev, struct rproc *rproc) +{ + /* This shouldn't be possible */ + WARN_ON(1); + + return 0; +} + +static inline int rproc_tee_load_fw(struct rproc *rproc, const struct firmware *fw) +{ + /* This shouldn't be possible */ + WARN_ON(1); + + return 0; +} + +static inline int rproc_tee_start(struct rproc *rproc) +{ + /* This shouldn't be possible */ + WARN_ON(1); + + return 0; +} + +static inline int rproc_tee_stop(struct rproc *rproc) +{ + /* This shouldn't be possible */ + WARN_ON(1); + + return 0; +} + +static inline void rproc_tee_release_fw(struct rproc *rproc) +{ + /* This shouldn't be possible */ + WARN_ON(1); +} + +static inline struct resource_table * +rproc_tee_find_loaded_rsc_table(struct rproc *rproc, const struct firmware *fw) +{ + /* This shouldn't be possible */ + WARN_ON(1); + + return NULL; +} +#endif /* CONFIG_REMOTEPROC_TEE */ +#endif /* REMOTEPROC_TEE_H */

The "st,stm32mp1-m4-tee" compatible is utilized in a system configuration where the Cortex-M4 firmware is loaded by the Trusted Execution Environment (TEE).

For instance, this compatible is used in both the Linux and OP-TEE device trees: - In OP-TEE, a node is defined in the device tree with the "st,stm32mp1-m4-tee" compatible to support signed remoteproc firmware. Based on DT properties, the OP-TEE remoteproc framework is initiated to expose a trusted application service to authenticate and load the remote processor firmware provided by the Linux remoteproc framework, as well as to start and stop the remote processor. - In Linux, when the compatibility is set, the Cortex-M resets should not be declared in the device tree. In such a configuration, the reset is managed by the OP-TEE remoteproc driver and is no longer accessible from the Linux kernel.

Associated with this new compatible, add the "st,proc-id" property to identify the remote processor. This ID is used to define a unique ID, common between Linux, U-Boot, and OP-TEE, to identify a coprocessor. This ID will be used in requests to the OP-TEE remoteproc Trusted Application to specify the remote processor.

Signed-off-by: Arnaud Pouliquen arnaud.pouliquen@foss.st.com Reviewed-by: Rob Herring (Arm) robh@kernel.org --- .../bindings/remoteproc/st,stm32-rproc.yaml | 58 ++++++++++++++++--- 1 file changed, 50 insertions(+), 8 deletions(-)

diff --git a/Documentation/devicetree/bindings/remoteproc/st,stm32-rproc.yaml b/Documentation/devicetree/bindings/remoteproc/st,stm32-rproc.yaml index 370af61d8f28..409123cd4667 100644 --- a/Documentation/devicetree/bindings/remoteproc/st,stm32-rproc.yaml +++ b/Documentation/devicetree/bindings/remoteproc/st,stm32-rproc.yaml @@ -16,7 +16,12 @@ maintainers:

properties: compatible: - const: st,stm32mp1-m4 + enum: + - st,stm32mp1-m4 + - st,stm32mp1-m4-tee + description: + Use "st,stm32mp1-m4" for the Cortex-M4 coprocessor management by non-secure context + Use "st,stm32mp1-m4-tee" for the Cortex-M4 coprocessor management by secure context

reg: description: @@ -43,6 +48,10 @@ properties: - description: The offset of the hold boot setting register - description: The field mask of the hold boot

+ st,proc-id: + description: remote processor identifier + $ref: /schemas/types.yaml#/definitions/uint32 + st,syscfg-tz: deprecated: true description: @@ -142,21 +151,43 @@ properties: required: - compatible - reg - - resets

allOf: - if: properties: - reset-names: - not: - contains: - const: hold_boot + compatible: + contains: + const: st,stm32mp1-m4 then: + if: + properties: + reset-names: + not: + contains: + const: hold_boot + then: + required: + - st,syscfg-holdboot + else: + properties: + st,syscfg-holdboot: false + required: + - reset-names required: - - st,syscfg-holdboot - else: + - resets + + - if: + properties: + compatible: + contains: + const: st,stm32mp1-m4-tee + then: properties: st,syscfg-holdboot: false + reset-names: false + resets: false + required: + - st,proc-id

additionalProperties: false

@@ -188,5 +219,16 @@ examples: st,syscfg-rsc-tbl = <&tamp 0x144 0xFFFFFFFF>; st,syscfg-m4-state = <&tamp 0x148 0xFFFFFFFF>; }; + - | + #include <dt-bindings/reset/stm32mp1-resets.h> + m4@10000000 { + compatible = "st,stm32mp1-m4-tee"; + reg = <0x10000000 0x40000>, + <0x30000000 0x40000>, + <0x38000000 0x10000>; + st,proc-id = <0>; + st,syscfg-rsc-tbl = <&tamp 0x144 0xFFFFFFFF>; + st,syscfg-m4-state = <&tamp 0x148 0xFFFFFFFF>; + };

...

The new TEE remoteproc driver is used to manage remote firmware in a secure, trusted context. The 'st,stm32mp1-m4-tee' compatibility is introduced to delegate the loading of the firmware to the trusted execution context. In such cases, the firmware should be signed and adhere to the image format defined by the TEE.

Signed-off-by: Arnaud Pouliquen arnaud.pouliquen@foss.st.com --- drivers/remoteproc/stm32_rproc.c | 57 ++++++++++++++++++++++++++++++-- 1 file changed, 54 insertions(+), 3 deletions(-)

diff --git a/drivers/remoteproc/stm32_rproc.c b/drivers/remoteproc/stm32_rproc.c index b1bda314ca85..829dfd440dbf 100644 --- a/drivers/remoteproc/stm32_rproc.c +++ b/drivers/remoteproc/stm32_rproc.c @@ -18,6 +18,7 @@ #include <linux/pm_wakeirq.h> #include <linux/regmap.h> #include <linux/remoteproc.h> +#include <linux/remoteproc_tee.h> #include <linux/reset.h> #include <linux/slab.h> #include <linux/workqueue.h> @@ -255,6 +256,19 @@ static int stm32_rproc_release(struct rproc *rproc) return 0; }

+static int stm32_rproc_tee_stop(struct rproc *rproc) +{ + int err; + + stm32_rproc_request_shutdown(rproc); + + err = rproc_tee_stop(rproc); + if (err) + return err; + + return stm32_rproc_release(rproc); +} + static int stm32_rproc_prepare(struct rproc *rproc) { struct device *dev = rproc->dev.parent; @@ -691,8 +705,20 @@ static const struct rproc_ops st_rproc_ops = { .get_boot_addr = rproc_elf_get_boot_addr, };

+static const struct rproc_ops st_rproc_tee_ops = { + .prepare = stm32_rproc_prepare, + .start = rproc_tee_start, + .stop = stm32_rproc_tee_stop, + .kick = stm32_rproc_kick, + .load = rproc_tee_load_fw, + .parse_fw = rproc_tee_parse_fw, + .find_loaded_rsc_table = rproc_tee_find_loaded_rsc_table, + .release_fw = rproc_tee_release_fw, +}; + static const struct of_device_id stm32_rproc_match[] = { { .compatible = "st,stm32mp1-m4" }, + { .compatible = "st,stm32mp1-m4-tee" }, {}, }; MODULE_DEVICE_TABLE(of, stm32_rproc_match); @@ -853,15 +879,36 @@ static int stm32_rproc_probe(struct platform_device *pdev) struct device_node *np = dev->of_node; struct rproc *rproc; unsigned int state; + u32 proc_id; int ret;

ret = dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(32)); if (ret) return ret;

- rproc = devm_rproc_alloc(dev, np->name, &st_rproc_ops, NULL, sizeof(*ddata)); - if (!rproc) - return -ENOMEM; + if (of_device_is_compatible(np, "st,stm32mp1-m4-tee")) { + /* + * Delegate the firmware management to the secure context. + * The firmware loaded has to be signed. + */ + ret = of_property_read_u32(np, "st,proc-id", &proc_id); + if (ret) { + dev_err(dev, "failed to read st,rproc-id property\n"); + return ret; + } + + rproc = devm_rproc_alloc(dev, np->name, &st_rproc_tee_ops, NULL, sizeof(*ddata)); + if (!rproc) + return -ENOMEM; + + ret = rproc_tee_register(dev, rproc, proc_id); + if (ret) + return dev_err_probe(dev, ret, "signed firmware not supported by TEE\n"); + } else { + rproc = devm_rproc_alloc(dev, np->name, &st_rproc_ops, NULL, sizeof(*ddata)); + if (!rproc) + return -ENOMEM; + }

ddata = rproc->priv;

@@ -913,6 +960,8 @@ static int stm32_rproc_probe(struct platform_device *pdev) dev_pm_clear_wake_irq(dev); device_init_wakeup(dev, false); } + rproc_tee_unregister(dev, rproc); + return ret; }

@@ -933,6 +982,8 @@ static void stm32_rproc_remove(struct platform_device *pdev) dev_pm_clear_wake_irq(dev); device_init_wakeup(dev, false); } + + rproc_tee_unregister(dev, rproc); }

static int stm32_rproc_suspend(struct device *dev)