On Fri, Mar 29, 2024 at 09:58:11AM +0100, Arnaud POULIQUEN wrote:
> Hello Mathieu,
>
> On 3/27/24 18:07, Mathieu Poirier wrote:
> > On Tue, Mar 26, 2024 at 08:18:23PM +0100, Arnaud POULIQUEN wrote:
> >> 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.pouliq...@foss.st.com>
> >>>> ---
> >>>> 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.pouliq...@foss.st.com>
> >>>> + */
> >>>> +
> >>>> +#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).
> >>
> >
> > Yes
> >
> >> So please just comfirm your preference.
> >>
> >
> > Definitely keep ->cached_table to NULL.
> >
> >>>
> >>>> +
> >>>> + 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.
> >
> > iounmap(entry->rproc->rsc_table);
> >
> > What am I missing?
>
> rproc->rsc_table is a field that can be updated by remoteproc_core.
> How can we garanty in tee_remoteproc that it still points to the mapped
> resource
> table?
By making sure the core doesn't touch rproc->rsc_table when
rproc->tee_interface is valid.
> As the remoteproc_tee maps the pointer, it seems reliable that it stores it
> for
> unmap.
>
Doing so creates a shadow value that is confusing and really hard to maintain
going forward.
> Seems also that I also missed to handle the case where rproc_fw_boot()
> fails[3]
> (not done yet).
>
> [3]https://elixir.bootlin.com/linux/latest/source/drivers/remoteproc/remoteproc_core.c#L1442
>
>
> >
> >>
> >>>
> >>>> +
> >>>> + 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]
> >
> > In [1], on line 1554, add a check for rproc->tee_interface and if it is
> > valid
> > call rproc_find_loaded_rsc_table().
> >
> >> and we need to reapply the configuration in rproc_start() called during the
> >> recovery[2]
> >
> > 1) Rename rproc_set_rsc_table() to rproc_set_rsc_table_on_attach()
> > 2) Introduce a new function called rproc_set_rsc_table_on_start()
> > 3) Move code from [2], line 1278 to 1292, to that new function. In the new
> > function, add a check on rproc->tee_interface. If it is valid then call
> > rproc_find_loaded_rsc_table().
> > 4) in rproc_start(), replace lines 1278 to 1292 with a call to
> > rproc_set_rsc_table_on_start().
>
>
> I will try this
>
Ok
> Thanks!
> Arnaud
>
> >
> >> [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
> >>
> >
> > I was thinking more along the lines of try_module_get() and module_put() to
> > avoid bloating the core.
> >
> >> 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
> >>>>
