Re: [PATCH v4 1/4] remoteproc: Add TEE support

[Arnaud POULIQUEN]

Hello Mathieu,

On 3/25/24 17:46, Mathieu Poirier wrote:
> On Fri, Mar 08, 2024 at 03:47:05PM +0100, Arnaud Pouliquen wrote:
>> Add a remoteproc TEE (Trusted Execution Environment) driver
>> that will be probed by the TEE bus. If the associated Trusted
>> application is supported on secure part this device offers a client
> 
> Device or driver?  I thought I touched on that before.

Right, I changed the first instance and missed this one

> 
>> interface to load a firmware in the secure part.
>> This firmware could be authenticated by the secure trusted application.
>>
>> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxxxxxxx>
>> ---
>> Updates from V3:
>> - rework TEE_REMOTEPROC description in Kconfig
>> - fix some namings
>> - add tee_rproc_parse_fw  to support rproc_ops::parse_fw
>> - add proc::tee_interface;
>> - add rproc struct as parameter of the tee_rproc_register() function
>> ---
>>  drivers/remoteproc/Kconfig          |  10 +
>>  drivers/remoteproc/Makefile         |   1 +
>>  drivers/remoteproc/tee_remoteproc.c | 434 ++++++++++++++++++++++++++++
>>  include/linux/remoteproc.h          |   4 +
>>  include/linux/tee_remoteproc.h      | 112 +++++++
>>  5 files changed, 561 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..2cf1431b2b59 100644
>> --- a/drivers/remoteproc/Kconfig
>> +++ b/drivers/remoteproc/Kconfig
>> @@ -365,6 +365,16 @@ config XLNX_R5_REMOTEPROC
>>  
>>  	  It's safe to say N if not interested in using RPU r5f cores.
>>  
>> +
>> +config TEE_REMOTEPROC
>> +	tristate "remoteproc support by a TEE application"
> 
> s/remoteproc/Remoteproc
> 
>> +	depends on OPTEE
>> +	help
>> +	  Support a remote processor with a TEE application. The Trusted
>> +	  Execution Context is responsible for loading the trusted firmware
>> +	  image and managing the remote processor's lifecycle.
>> +	  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..c855210e52e3
>> --- /dev/null
>> +++ b/drivers/remoteproc/tee_remoteproc.c
>> @@ -0,0 +1,434 @@
>> +// SPDX-License-Identifier: GPL-2.0-or-later
>> +/*
>> + * Copyright (C) STMicroelectronics 2024 - All Rights Reserved
>> + * Author: Arnaud Pouliquen <arnaud.pouliquen@xxxxxxxxxxx>
>> + */
>> +
>> +#include <linux/firmware.h>
>> +#include <linux/io.h>
>> +#include <linux/module.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_context {
>> +	struct list_head sessions;
>> +	struct tee_context *tee_ctx;
>> +	struct device *dev;
>> +};
>> +
>> +static struct tee_rproc_context *tee_rproc_ctx;
>> +
>> +static void tee_rproc_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 rproc *rproc, const struct firmware *fw)
>> +{
>> +	struct tee_ioctl_invoke_arg arg;
>> +	struct tee_param param[MAX_TEE_PARAM_ARRY_MEMBER];
>> +	struct tee_rproc *trproc = rproc->tee_interface;
>> +	struct tee_shm *fw_shm;
>> +	int ret;
> 
> Declarations in reverse ascending order here and everywhere in the driver.
> Sometimes it is done properly, sometimes it isn't. 
> 
>> +
>> +	if (!trproc)
>> +		return -EINVAL;
>> +
>> +	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);
>> +
>> +	tee_rproc_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);
>> +
>> +struct resource_table *tee_rproc_get_loaded_rsc_table(struct rproc *rproc, size_t *table_sz)
>> +{
>> +	struct tee_ioctl_invoke_arg arg;
>> +	struct tee_param param[MAX_TEE_PARAM_ARRY_MEMBER];
>> +	struct tee_rproc *trproc = rproc->tee_interface;
>> +	struct resource_table *rsc_table;
>> +	int ret;
>> +
>> +	if (!trproc)
>> +		return ERR_PTR(-EINVAL);
>> +
>> +	tee_rproc_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 ERR_PTR(-EIO);
>> +	}
>> +
>> +	*table_sz = param[2].u.value.a;
>> +
>> +	/* If the size is null no resource table defined in the image */
>> +	if (!*table_sz)
>> +		return NULL;
>> +
>> +	/* Store the resource table address that would be updated by the remote core. */
>> +	rsc_table = ioremap_wc(param[1].u.value.a, *table_sz);
>> +	if (IS_ERR_OR_NULL(rsc_table)) {
>> +		dev_err(tee_rproc_ctx->dev, "Unable to map memory region: %lld+%zx\n",
>> +			param[1].u.value.a, *table_sz);
>> +		return ERR_PTR(-ENOMEM);
>> +	}
>> +
>> +	return rsc_table;
>> +}
>> +EXPORT_SYMBOL_GPL(tee_rproc_get_loaded_rsc_table);
>> +
>> +int tee_rproc_parse_fw(struct rproc *rproc, const struct firmware *fw)
>> +{
>> +	struct tee_rproc *trproc = rproc->tee_interface;
>> +	struct resource_table *rsc_table;
>> +	size_t table_sz;
>> +	int ret;
>> +
>> +	ret = tee_rproc_load_fw(rproc, fw);
>> +	if (ret)
>> +		return ret;
>> +
>> +	rsc_table = tee_rproc_get_loaded_rsc_table(rproc, &table_sz);
>> +	if (IS_ERR(rsc_table))
>> +		return PTR_ERR(rsc_table);
>> +
>> +	/* Create a copy of the resource table to have same behaviour than the elf loader. */
>> +	rproc->cached_table = kmemdup(rsc_table, table_sz, GFP_KERNEL);
>> +	if (!rproc->cached_table)
>> +		return -ENOMEM;
> 
> Why not ->table_ptr and setting ->cached_table to NULL?

It was my plan preparing this version. But during implementarion it looks
to me that having exactly same behavior than the ELF loader would be
simpler to maintain the remoteproc avoiding to update in the remoteproc core
to manage for the cached resource table (see also my comment below abourt recovery)
That why I propose this implementation

That said what you proposal should also work (with some updates in
remoteproc_core for the management of the cached table).

So please just comfirm your preference.

> 
>> +
>> +	rproc->table_ptr = rproc->cached_table;
>> +	rproc->table_sz = table_sz;
>> +	trproc->rsc_table = rsc_table;
> 
> I really don't see why this is needed, please remove and use rproc->table_ptr
> instead.

I need to store it for the iounmap in tee_rproc_remove.

> 
>> +
>> +	return 0;
>> +}
>> +EXPORT_SYMBOL_GPL(tee_rproc_parse_fw);
>> +
>> +struct resource_table *tee_rproc_find_loaded_rsc_table(struct rproc *rproc,
>> +						       const struct firmware *fw)
>> +{
>> +	struct tee_rproc *trproc = rproc->tee_interface;
>> +	struct resource_table *rsc_table;
>> +	size_t table_sz;
>> +
>> +	if (!trproc)
>> +		return ERR_PTR(-EINVAL);
>> +
>> +	/* Check if the resourse table has already been obtained in tee_rproc_parse_fw() */
>> +	if (trproc->rsc_table)
>> +		return trproc->rsc_table;
> 
> Again, why not simply use rproc->rsc_table?  This function should only return
> the resource table that was set in tee_rproc_parse_fw(). 

In case of recovery rproc->_rsc_table point to the cached table [1]
and we need to reapply the configuration in rproc_start() called during the
recovery[2]
[1]https://elixir.bootlin.com/linux/latest/source/drivers/remoteproc/remoteproc_core.c#L1586
[2]https://elixir.bootlin.com/linux/latest/source/drivers/remoteproc/remoteproc_core.c#L1287

> 
>> +
>> +	rsc_table = tee_rproc_get_loaded_rsc_table(rproc, &table_sz);
>> +	if (IS_ERR(rsc_table))
>> +		return rsc_table;
>> +
>> +	rproc->table_sz = table_sz;
>> +	trproc->rsc_table = rsc_table;
>> +
>> +	return rsc_table;
>> +}
>> +EXPORT_SYMBOL_GPL(tee_rproc_find_loaded_rsc_table);
>> +
>> +int tee_rproc_start(struct rproc *rproc)
>> +{
>> +	struct tee_ioctl_invoke_arg arg;
>> +	struct tee_param param[MAX_TEE_PARAM_ARRY_MEMBER];
>> +	struct tee_rproc *trproc = rproc->tee_interface;
>> +	int ret;
>> +
>> +	if (!trproc)
>> +		return -EINVAL;
>> +
>> +	tee_rproc_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 rproc *rproc)
>> +{
>> +	struct tee_ioctl_invoke_arg arg;
>> +	struct tee_param param[MAX_TEE_PARAM_ARRY_MEMBER];
>> +	struct tee_rproc *trproc = rproc->tee_interface;
>> +	int ret;
>> +
>> +	if (!trproc)
>> +		return -EINVAL;
>> +
>> +	tee_rproc_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 (!rproc->table_ptr)
>> +		return ret;
>> +
>> +	iounmap(trproc->rsc_table);
>> +	trproc->rsc_table = NULL;
>> +	rproc->table_ptr = NULL;
>> +
>> +	return 0;
>> +}
>> +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, struct rproc *rproc, unsigned int rproc_id)
>> +{
>> +	struct tee_client_device *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;
>> +
>> +	/*
>> +	 * 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 (!tee_rproc_ctx)
>> +		return ERR_PTR(-EPROBE_DEFER);
>> +
>> +	trproc =  devm_kzalloc(dev, sizeof(*trproc), GFP_KERNEL);
>> +	if (!trproc)
>> +		return ERR_PTR(-ENOMEM);
>> +
>> +	tee_device = to_tee_client_device(tee_rproc_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(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;
>> +
>> +	trproc->rproc = rproc;
>> +	rproc->tee_interface = trproc;
>> +
>> +	list_add_tail(&trproc->node, &tee_rproc_ctx->sessions);
>> +
>> +	return trproc;
> 
> Once this function was called by a client, what prevents a user from unloading
> the tee_remoteproc module and breaking everything?

Good point! seems better toremove the module build capability

Thanks,
Arnaud

> 
>> +}
>> +EXPORT_SYMBOL_GPL(tee_rproc_register);
>> +
>> +int tee_rproc_unregister(struct tee_rproc *trproc)
>> +{
> 
> If you pass a struct_rproc instead of a struct tee_rproc there is no need for
> tee_rproc::rproc, which is only ever used in this function.
> 
> 
>> +	struct rproc *rproc = trproc->rproc;
>> +	int ret;
>> +
>> +	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);
>> +	rproc->tee_interface = NULL;
>> +
>> +	return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(tee_rproc_unregister);
>> +
>> +static int tee_rproc_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 tee_rproc_probe(struct device *dev)
>> +{
>> +	struct tee_context *tee_ctx;
>> +	int ret;
>> +
>> +	/* Open context with TEE driver */
>> +	tee_ctx = tee_client_open_context(NULL, tee_rproc_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_rproc_ctx) {
>> +		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);
>> +		if (entry->rsc_table)
>> +			iounmap(entry->rsc_table);
>> +		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/remoteproc.h b/include/linux/remoteproc.h
>> index b4795698d8c2..8b678009e481 100644
>> --- a/include/linux/remoteproc.h
>> +++ b/include/linux/remoteproc.h
>> @@ -503,6 +503,8 @@ enum rproc_features {
>>  	RPROC_MAX_FEATURES,
>>  };
>>  
>> +struct tee_rproc;
>> +
>>  /**
>>   * struct rproc - represents a physical remote processor device
>>   * @node: list node of this rproc object
>> @@ -545,6 +547,7 @@ enum rproc_features {
>>   * @cdev: character device of the rproc
>>   * @cdev_put_on_release: flag to indicate if remoteproc should be shutdown on @char_dev release
>>   * @features: indicate remoteproc features
>> + * @tee_interface: pointer to the remoteproc tee context
>>   */
>>  struct rproc {
>>  	struct list_head node;
>> @@ -586,6 +589,7 @@ struct rproc {
>>  	struct cdev cdev;
>>  	bool cdev_put_on_release;
>>  	DECLARE_BITMAP(features, RPROC_MAX_FEATURES);
>> +	struct tee_rproc *tee_interface;
>>  };
>>  
>>  /**
>> diff --git a/include/linux/tee_remoteproc.h b/include/linux/tee_remoteproc.h
>> new file mode 100644
>> index 000000000000..571e47190d02
>> --- /dev/null
>> +++ b/include/linux/tee_remoteproc.h
>> @@ -0,0 +1,112 @@
>> +/* SPDX-License-Identifier: GPL-2.0-or-later */
>> +/*
>> + * Copyright(c) 2024 STMicroelectronics - All Rights Reserved
>> + */
>> +
>> +#ifndef TEE_REMOTEPROC_H
>> +#define TEE_REMOTEPROC_H
>> +
>> +#include <linux/tee_drv.h>
>> +#include <linux/firmware.h>
>> +#include <linux/remoteproc.h>
>> +
>> +struct rproc;
>> +
>> +/**
>> + * 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_table:		Resource table virtual address.
>> + */
>> +struct tee_rproc {
>> +	struct list_head node;
>> +	struct rproc *rproc;
>> +	struct device *parent;
>> +	u32 rproc_id;
>> +	u32 session_id;
>> +	struct resource_table *rsc_table;
>> +};
>> +
>> +#if IS_REACHABLE(CONFIG_TEE_REMOTEPROC)
>> +
>> +struct tee_rproc *tee_rproc_register(struct device *dev, struct rproc *rproc,
>> +				     unsigned int rproc_id);
>> +int tee_rproc_unregister(struct tee_rproc *trproc);
>> +int tee_rproc_parse_fw(struct rproc *rproc, const struct firmware *fw);
>> +int tee_rproc_load_fw(struct rproc *rproc, const struct firmware *fw);
>> +struct resource_table *tee_rproc_get_loaded_rsc_table(struct rproc *rproc, size_t *table_sz);
>> +struct resource_table *tee_rproc_find_loaded_rsc_table(struct rproc *rproc,
>> +						       const struct firmware *fw);
>> +int tee_rproc_start(struct rproc *rproc);
>> +int tee_rproc_stop(struct rproc *rproc);
>> +
>> +#else
>> +
>> +static inline struct tee_rproc *tee_rproc_register(struct device *dev, struct rproc *rproc,
>> +						   unsigned int rproc_id)
>> +{
>> +	return ERR_PTR(-ENODEV);
>> +}
>> +
>> +static int tee_rproc_parse_fw(struct rproc *rproc, const struct firmware *fw)
>> +{
>> +	/* This shouldn't be possible */
>> +	WARN_ON(1);
>> +
>> +	return 0;
>> +}
>> +
>> +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 rproc *rproc,  const struct firmware *fw)
>> +{
>> +	/* This shouldn't be possible */
>> +	WARN_ON(1);
>> +
>> +	return 0;
>> +}
>> +
>> +static inline int tee_rproc_start(struct rproc *rproc)
>> +{
>> +	/* This shouldn't be possible */
>> +	WARN_ON(1);
>> +
>> +	return 0;
>> +}
>> +
>> +static inline int tee_rproc_stop(struct rproc *rproc)
>> +{
>> +	/* This shouldn't be possible */
>> +	WARN_ON(1);
>> +
>> +	return 0;
>> +}
>> +
>> +static inline struct resource_table *
>> +tee_rproc_get_loaded_rsc_table(struct rproc *rproc, size_t *table_sz)
>> +{
>> +	/* This shouldn't be possible */
>> +	WARN_ON(1);
>> +
>> +	return NULL;
>> +}
>> +
>> +static inline struct resource_table *
>> +tee_rproc_find_loaded_rsc_table(struct rproc *rproc, const struct firmware *fw)
>> +{
>> +	/* This shouldn't be possible */
>> +	WARN_ON(1);
>> +
>> +	return NULL;
>> +}
>> +#endif /* CONFIG_TEE_REMOTEPROC */
>> +#endif /* TEE_REMOTEPROC_H */
>> -- 
>> 2.25.1
>>