Re: [PATCH v2 1/4] remoteproc: Add TEE support

From: Mathieu Poirier
Date: Fri Jan 26 2024 - 13:03:42 EST


On Thu, Jan 18, 2024 at 11:04:30AM +0100, Arnaud Pouliquen wrote:
> From: Arnaud Pouliquen <arnaud.pouliquen@xxxxxx>
>
> Add a remoteproc TEE (Trusted Execution Environment) device
> that will be probed by the TEE bus. If the associated Trusted
> application is supported on secure part this device offers a client
> interface to load a firmware in the secure part.
> This firmware could be authenticated and decrypted by the secure
> trusted application.
>
> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxx>
> ---
> drivers/remoteproc/Kconfig | 9 +
> drivers/remoteproc/Makefile | 1 +
> drivers/remoteproc/tee_remoteproc.c | 393 ++++++++++++++++++++++++++++
> include/linux/tee_remoteproc.h | 99 +++++++
> 4 files changed, 502 insertions(+)
> create mode 100644 drivers/remoteproc/tee_remoteproc.c
> create mode 100644 include/linux/tee_remoteproc.h
>
> diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig
> index 48845dc8fa85..85299606806c 100644
> --- a/drivers/remoteproc/Kconfig
> +++ b/drivers/remoteproc/Kconfig
> @@ -365,6 +365,15 @@ config XLNX_R5_REMOTEPROC
>
> It's safe to say N if not interested in using RPU r5f cores.
>
> +
> +config TEE_REMOTEPROC
> + tristate "trusted firmware support by a TEE application"
> + depends on OPTEE
> + help
> + Support for trusted remote processors firmware. The firmware
> + authentication and/or decryption are managed by a trusted application.
> + This can be either built-in or a loadable module.
> +
> endif # REMOTEPROC
>
> endmenu
> diff --git a/drivers/remoteproc/Makefile b/drivers/remoteproc/Makefile
> index 91314a9b43ce..fa8daebce277 100644
> --- a/drivers/remoteproc/Makefile
> +++ b/drivers/remoteproc/Makefile
> @@ -36,6 +36,7 @@ obj-$(CONFIG_RCAR_REMOTEPROC) += rcar_rproc.o
> obj-$(CONFIG_ST_REMOTEPROC) += st_remoteproc.o
> obj-$(CONFIG_ST_SLIM_REMOTEPROC) += st_slim_rproc.o
> obj-$(CONFIG_STM32_RPROC) += stm32_rproc.o
> +obj-$(CONFIG_TEE_REMOTEPROC) += tee_remoteproc.o
> obj-$(CONFIG_TI_K3_DSP_REMOTEPROC) += ti_k3_dsp_remoteproc.o
> obj-$(CONFIG_TI_K3_R5_REMOTEPROC) += ti_k3_r5_remoteproc.o
> obj-$(CONFIG_XLNX_R5_REMOTEPROC) += xlnx_r5_remoteproc.o
> diff --git a/drivers/remoteproc/tee_remoteproc.c b/drivers/remoteproc/tee_remoteproc.c
> new file mode 100644
> index 000000000000..49e1e0caf889
> --- /dev/null
> +++ b/drivers/remoteproc/tee_remoteproc.c
> @@ -0,0 +1,393 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright (C) STMicroelectronics 2023 - All Rights Reserved
> + * Author: Arnaud Pouliquen <arnaud.pouliquen@xxxxxx>
> + */
> +
> +#include <linux/firmware.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of_address.h>
> +#include <linux/of_device.h>
> +#include <linux/of_reserved_mem.h>
> +#include <linux/remoteproc.h>
> +#include <linux/slab.h>
> +#include <linux/tee_drv.h>
> +#include <linux/tee_remoteproc.h>
> +
> +#include "remoteproc_internal.h"
> +
> +#define MAX_TEE_PARAM_ARRY_MEMBER 4
> +
> +/*
> + * Authentication of the firmware and load in the remote processor memory
> + *
> + * [in] params[0].value.a: unique 32bit identifier of the remote processor
> + * [in] params[1].memref: buffer containing the image of the buffer
> + */
> +#define TA_RPROC_FW_CMD_LOAD_FW 1
> +
> +/*
> + * Start the remote processor
> + *
> + * [in] params[0].value.a: unique 32bit identifier of the remote processor
> + */
> +#define TA_RPROC_FW_CMD_START_FW 2
> +
> +/*
> + * Stop the remote processor
> + *
> + * [in] params[0].value.a: unique 32bit identifier of the remote processor
> + */
> +#define TA_RPROC_FW_CMD_STOP_FW 3
> +
> +/*
> + * Return the address of the resource table, or 0 if not found
> + * No check is done to verify that the address returned is accessible by
> + * the non secure context. If the resource table is loaded in a protected
> + * memory the access by the non secure context will lead to a data abort.
> + *
> + * [in] params[0].value.a: unique 32bit identifier of the remote processor
> + * [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
> +
> +/*
> + * Return the address of the core dump
> + *
> + * [in] params[0].value.a: unique 32bit identifier of the remote processor
> + * [out] params[1].memref: address of the core dump image if exist,
> + * else return Null
> + */
> +#define TA_RPROC_FW_CMD_GET_COREDUMP 5
> +
> +struct tee_rproc_mem {
> + char name[20];
> + void __iomem *cpu_addr;
> + phys_addr_t bus_addr;
> + u32 dev_addr;
> + size_t size;
> +};
> +
> +struct tee_rproc_context {
> + struct list_head sessions;
> + struct tee_context *tee_ctx;
> + struct device *dev;
> +};
> +
> +static struct tee_rproc_context *tee_rproc_ctx;
> +
> +static void prepare_args(struct tee_rproc *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_ARRY_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,
> + };
> +}
> +
> +int tee_rproc_load_fw(struct tee_rproc *trproc, const struct firmware *fw)
> +{
> + struct tee_ioctl_invoke_arg arg;
> + struct tee_param param[MAX_TEE_PARAM_ARRY_MEMBER];
> + struct tee_shm *fw_shm;
> + int ret;
> +
> + fw_shm = tee_shm_register_kernel_buf(tee_rproc_ctx->tee_ctx, (void *)fw->data, fw->size);
> + if (IS_ERR(fw_shm))
> + return PTR_ERR(fw_shm);
> +
> + 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(tee_rproc_ctx->tee_ctx, &arg, param);
> + if (ret < 0 || arg.ret != 0) {
> + dev_err(tee_rproc_ctx->dev,
> + "TA_RPROC_FW_CMD_LOAD_FW invoke failed TEE err: %x, ret:%x\n",
> + arg.ret, ret);
> + if (!ret)
> + ret = -EIO;
> + }
> +
> + tee_shm_free(fw_shm);
> +
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(tee_rproc_load_fw);
> +
> +int rproc_tee_get_rsc_table(struct tee_rproc *trproc)
> +{
> + struct tee_ioctl_invoke_arg arg;
> + struct tee_param param[MAX_TEE_PARAM_ARRY_MEMBER];
> + struct rproc *rproc = trproc->rproc;
> + size_t rsc_size;
> + int ret;
> +
> + 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(tee_rproc_ctx->tee_ctx, &arg, param);
> + if (ret < 0 || arg.ret != 0) {
> + dev_err(tee_rproc_ctx->dev,
> + "TA_RPROC_FW_CMD_GET_RSC_TABLE invoke failed TEE err: %x, ret:%x\n",
> + arg.ret, ret);
> + return -EIO;
> + }
> +
> + rsc_size = param[2].u.value.a;
> +
> + /* If the size is null no resource table defined in the image */
> + if (!rsc_size)
> + return 0;
> +
> + /* Store the resource table address that would be updated by the remote core . */
> + trproc->rsc_va = ioremap_wc(param[1].u.value.a, rsc_size);
> + if (IS_ERR_OR_NULL(trproc->rsc_va)) {
> + dev_err(tee_rproc_ctx->dev, "Unable to map memory region: %lld+%zx\n",
> + param[1].u.value.a, rsc_size);
> + trproc->rsc_va = NULL;
> + return -ENOMEM;
> + }
> +
> + /*
> + * A cached table is requested as the physical address is not mapped yet
> + * but remoteproc needs to parse the table for resources.
> + */
> + rproc->cached_table = kmemdup((__force void *)trproc->rsc_va, rsc_size, GFP_KERNEL);
> + if (!rproc->cached_table)
> + return -ENOMEM;
> +
> + rproc->table_ptr = rproc->cached_table;
> + rproc->table_sz = rsc_size;
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(rproc_tee_get_rsc_table);
> +
> +struct resource_table *tee_rproc_get_loaded_rsc_table(struct tee_rproc *trproc)
> +{
> + return (__force struct resource_table *)trproc->rsc_va;
> +}
> +EXPORT_SYMBOL_GPL(tee_rproc_get_loaded_rsc_table);
> +
> +int tee_rproc_start(struct tee_rproc *trproc)
> +{
> + struct tee_ioctl_invoke_arg arg;
> + struct tee_param param[MAX_TEE_PARAM_ARRY_MEMBER];
> + int ret;
> +
> + prepare_args(trproc, TA_RPROC_FW_CMD_START_FW, &arg, param, 0);
> +
> + ret = tee_client_invoke_func(tee_rproc_ctx->tee_ctx, &arg, param);
> + if (ret < 0 || arg.ret != 0) {
> + dev_err(tee_rproc_ctx->dev,
> + "TA_RPROC_FW_CMD_START_FW invoke failed TEE err: %x, ret:%x\n",
> + arg.ret, ret);
> + if (!ret)
> + ret = -EIO;
> + }
> +
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(tee_rproc_start);
> +
> +int tee_rproc_stop(struct tee_rproc *trproc)
> +{
> + struct tee_ioctl_invoke_arg arg;
> + struct tee_param param[MAX_TEE_PARAM_ARRY_MEMBER];
> + int ret;
> +
> + prepare_args(trproc, TA_RPROC_FW_CMD_STOP_FW, &arg, param, 0);
> +
> + ret = tee_client_invoke_func(tee_rproc_ctx->tee_ctx, &arg, param);
> + if (ret < 0 || arg.ret != 0) {
> + dev_err(tee_rproc_ctx->dev,
> + "TA_RPROC_FW_CMD_STOP_FW invoke failed TEE err: %x, ret:%x\n",
> + arg.ret, ret);
> + if (!ret)
> + ret = -EIO;
> + }
> + if (trproc->rsc_va)
> + iounmap(trproc->rsc_va);
> + trproc->rsc_va = NULL;
> +
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(tee_rproc_stop);
> +
> +static const struct tee_client_device_id stm32_tee_rproc_id_table[] = {
> + {UUID_INIT(0x80a4c275, 0x0a47, 0x4905,
> + 0x82, 0x85, 0x14, 0x86, 0xa9, 0x77, 0x1a, 0x08)},
> + {}
> +};
> +
> +struct tee_rproc *tee_rproc_register(struct device *dev, unsigned int rproc_id)
> +{
> + struct tee_client_device *rproc_tee_device;

This belongs to the TEE subsystem and as such would call it tee_device.

> + struct tee_ioctl_open_session_arg sess_arg;
> + struct tee_param param[MAX_TEE_PARAM_ARRY_MEMBER];
> + struct tee_rproc *trproc;
> + int ret;
> +
> + /*
> + * The device is not probed by the TEE bus. We ignore the reason (bus could be not yet
> + * probed or service not available in the secure firmware)
> + * Assumption here is that the TEE bus is not probed.
> + */
> + if (!tee_rproc_ctx)
> + return ERR_PTR(-EPROBE_DEFER);
> +
> + trproc = devm_kzalloc(dev, sizeof(*trproc), GFP_KERNEL);
> + if (!trproc)
> + return ERR_PTR(-ENOMEM);
> +
> + rproc_tee_device = to_tee_client_device(tee_rproc_ctx->dev);
> + memset(&sess_arg, 0, sizeof(sess_arg));
> +
> + /* Open session with rproc_tee load the OP-TEE Trusted Application */
> + memcpy(sess_arg.uuid, rproc_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(tee_rproc_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);
> + return ERR_PTR(-EINVAL);
> + }
> +
> + trproc->parent = dev;
> + trproc->rproc_id = rproc_id;
> + trproc->session_id = sess_arg.session;
> +
> + list_add_tail(&trproc->node, &tee_rproc_ctx->sessions);
> +
> + return trproc;
> +}
> +EXPORT_SYMBOL_GPL(tee_rproc_register);
> +
> +int tee_rproc_unregister(struct tee_rproc *trproc)
> +{
> + int ret;
> +
> + if (!tee_rproc_ctx)
> + return -ENODEV;
> +
> + ret = tee_client_close_session(tee_rproc_ctx->tee_ctx, trproc->session_id);
> + if (ret < 0)
> + dev_err(trproc->parent, "tee_client_close_session failed, err: %x\n", ret);
> +
> + list_del(&trproc->node);
> +
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(tee_rproc_unregister);
> +
> +static int tee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)

tee_rproc_ctx_match()

> +{
> + /* Today we support only the OP-TEE, could be extend to other tees */
> + return (ver->impl_id == TEE_IMPL_ID_OPTEE);
> +}
> +
> +static int tee_rproc_probe(struct device *dev)
> +{
> + struct tee_context *tee_ctx;
> + int ret;
> +
> + /* Only one RPROC OP-TEE device allowed */
> + if (tee_rproc_ctx) {
> + dev_err(dev, "An RPROC OP-TEE device was already initialized: only one allowed\n");
> + return -EBUSY;
> + }
> +
> + /* Open context with TEE driver */
> + tee_ctx = tee_client_open_context(NULL, tee_ctx_match, NULL, NULL);
> + if (IS_ERR(tee_ctx))
> + return PTR_ERR(tee_ctx);
> +
> + tee_rproc_ctx = devm_kzalloc(dev, sizeof(*tee_ctx), GFP_KERNEL);
> + if (!tee_ctx) {

There is a big problem here...

More comments on Monday.

Thanks,
Mathieu

> + ret = -ENOMEM;
> + goto err;
> + }
> +
> + tee_rproc_ctx->dev = dev;
> + tee_rproc_ctx->tee_ctx = tee_ctx;
> + INIT_LIST_HEAD(&tee_rproc_ctx->sessions);
> +
> + return 0;
> +err:
> + tee_client_close_context(tee_ctx);
> +
> + return ret;
> +}
> +
> +static int tee_rproc_remove(struct device *dev)
> +{
> + struct tee_rproc *entry, *tmp;
> +
> + list_for_each_entry_safe(entry, tmp, &tee_rproc_ctx->sessions, node) {
> + tee_client_close_session(tee_rproc_ctx->tee_ctx, entry->session_id);
> + list_del(&entry->node);
> + kfree(entry);
> + }
> +
> + tee_client_close_context(tee_rproc_ctx->tee_ctx);
> +
> + return 0;
> +}
> +
> +MODULE_DEVICE_TABLE(tee, stm32_tee_rproc_id_table);
> +
> +static struct tee_client_driver tee_rproc_fw_driver = {
> + .id_table = stm32_tee_rproc_id_table,
> + .driver = {
> + .name = KBUILD_MODNAME,
> + .bus = &tee_bus_type,
> + .probe = tee_rproc_probe,
> + .remove = tee_rproc_remove,
> + },
> +};
> +
> +static int __init tee_rproc_fw_mod_init(void)
> +{
> + return driver_register(&tee_rproc_fw_driver.driver);
> +}
> +
> +static void __exit tee_rproc_fw_mod_exit(void)
> +{
> + driver_unregister(&tee_rproc_fw_driver.driver);
> +}
> +
> +module_init(tee_rproc_fw_mod_init);
> +module_exit(tee_rproc_fw_mod_exit);
> +
> +MODULE_DESCRIPTION(" TEE remote processor control driver");
> +MODULE_LICENSE("GPL");
> diff --git a/include/linux/tee_remoteproc.h b/include/linux/tee_remoteproc.h
> new file mode 100644
> index 000000000000..537d6dc3b858
> --- /dev/null
> +++ b/include/linux/tee_remoteproc.h
> @@ -0,0 +1,99 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +/*
> + * Copyright(c) 2023 STMicroelectronics - All Rights Reserved
> + */
> +
> +#ifndef TEE_REMOTEPROC_H
> +#define TEE_REMOTEPROC_H
> +
> +#include <linux/remoteproc.h>
> +#include <linux/tee_drv.h>
> +
> +/**
> + * struct tee_rproc - TEE remoteproc structure
> + * @node: Reference in list
> + * @rproc: Remoteproc reference
> + * @parent: Parent device
> + * @rproc_id: Identifier of the target firmware
> + * @session_id: TEE session identifier
> + * @rsc_va: Resource table virtual address.
> + */
> +struct tee_rproc {
> + struct list_head node;
> + struct rproc *rproc;
> + struct device *parent;
> + u32 rproc_id;
> + u32 session_id;
> + void __iomem *rsc_va;
> +};
> +
> +#if IS_ENABLED(CONFIG_TEE_REMOTEPROC)
> +
> +struct tee_rproc *tee_rproc_register(struct device *dev, unsigned int rproc_id);
> +int tee_rproc_unregister(struct tee_rproc *trproc);
> +
> +int tee_rproc_load_fw(struct tee_rproc *trproc, const struct firmware *fw);
> +int rproc_tee_get_rsc_table(struct tee_rproc *trproc);
> +struct resource_table *tee_rproc_get_loaded_rsc_table(struct tee_rproc *trproc);
> +int tee_rproc_start(struct tee_rproc *trproc);
> +int tee_rproc_stop(struct tee_rproc *trproc);
> +
> +#else
> +
> +static inline struct tee_rproc *tee_rproc_register(struct device *dev, unsigned int rproc_id)
> +{
> + return ERR_PTR(-ENODEV);
> +}
> +
> +static inline int tee_rproc_unregister(struct tee_rproc *trproc)
> +{
> + /* This shouldn't be possible */
> + WARN_ON(1);
> +
> + return 0;
> +}
> +
> +static inline int tee_rproc_load_fw(struct tee_rproc *trproc,
> + const struct firmware *fw)
> +{
> + /* This shouldn't be possible */
> + WARN_ON(1);
> +
> + return 0;
> +}
> +
> +static inline int tee_rproc_start(struct tee_rproc *trproc)
> +{
> + /* This shouldn't be possible */
> + WARN_ON(1);
> +
> + return 0;
> +}
> +
> +static inline int tee_rproc_stop(struct tee_rproc *trproc)
> +{
> + /* This shouldn't be possible */
> + WARN_ON(1);
> +
> + return 0;
> +}
> +
> +static inline int rproc_tee_get_rsc_table(struct tee_rproc *trproc)
> +{
> + /* This shouldn't be possible */
> + WARN_ON(1);
> +
> + return 0;
> +}
> +
> +static inline struct resource_table *
> + tee_rproc_get_loaded_rsc_table(struct tee_rproc *trproc)
> +{
> + /* This shouldn't be possible */
> + WARN_ON(1);
> +
> + return NULL;
> +}
> +
> +#endif /* CONFIG_TEE_REMOTEPROC */
> +#endif /* TEE_REMOTEPROC_H */
> --
> 2.25.1
>