[PATCH v13 2/7] remoteproc: Add TEE support

Arnaud Pouliquen posted 7 patches 2 weeks, 6 days ago
[PATCH v13 2/7] remoteproc: Add TEE support
Posted by Arnaud Pouliquen 2 weeks, 6 days ago
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 driver offers a client
interface to load a firmware by the secure part.
This firmware could be authenticated by the secure trusted application.

Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
---
Updates from version V11:
- rename structures, functions, and variables from "tee_rproc_xxx" to
  "rproc_tee_xxx",
- update rproc_tee_register to return an error instead of
  "struct rproc_tee *" pointer,
- update rproc_tee_unregister argument from "struct rproc_tee *trproc"
  to "struct rproc *rproc",
- reword MODULE_DESCRIPTION.
---
 drivers/remoteproc/Kconfig          |  10 +
 drivers/remoteproc/Makefile         |   1 +
 drivers/remoteproc/remoteproc_tee.c | 510 ++++++++++++++++++++++++++++
 include/linux/remoteproc.h          |   4 +
 include/linux/remoteproc_tee.h      | 105 ++++++
 5 files changed, 630 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 955e4e38477e..d0284220a194 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
+	tristate "Remoteproc support by a TEE application"
+	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.
+
+	  It's safe to say N if you don't want to use remoteproc 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..f258b9304daf
--- /dev/null
+++ b/drivers/remoteproc/remoteproc_tee.c
@@ -0,0 +1,510 @@
+// 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/remoteproc.h>
+#include <linux/remoteproc_tee.h>
+#include <linux/slab.h>
+#include <linux/tee_drv.h>
+
+#define MAX_TEE_PARAM_ARRAY_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
+
+/*
+ * 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 (A_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;
+};
+
+static struct rproc_tee_context *rproc_tee_ctx;
+
+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,
+	};
+}
+
+void rproc_tee_release_fw(struct rproc *rproc)
+{
+	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
+	struct rproc_tee *trproc = rproc->rproc_tee_itf;
+	struct tee_ioctl_invoke_arg arg;
+	int ret;
+
+	if (!rproc) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/*
+	 * 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) {
+		ret = -EBUSY;
+		goto out;
+	}
+
+	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:%x\n",
+			arg.ret, ret);
+		ret = -EIO;
+	}
+
+out:
+	if (ret)
+		/* Unexpected state without solution to come back in a stable state */
+		dev_err(rproc_tee_ctx->dev, "Failed to release TEE remoteproc firmware: %d\n", ret);
+}
+EXPORT_SYMBOL_GPL(rproc_tee_release_fw);
+
+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->rproc_tee_itf;
+	struct tee_ioctl_invoke_arg arg;
+	struct tee_shm *fw_shm;
+	int ret;
+
+	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:%x\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->rproc_tee_itf;
+	struct tee_ioctl_invoke_arg arg;
+	int ret;
+
+	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:%x\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;
+}
+
+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;
+
+	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 (IS_ERR_OR_NULL(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);
+
+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);
+
+int rproc_tee_start(struct rproc *rproc)
+{
+	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
+	struct rproc_tee *trproc = rproc->rproc_tee_itf;
+	struct tee_ioctl_invoke_arg arg;
+	int ret = 0;
+
+	if (!trproc)
+		return -EINVAL;
+
+	rproc_tee_prepare_args(trproc, TA_RPROC_FW_CMD_START_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_FW_CMD_START_FW invoke failed TEE err: %x, ret:%x\n",
+			arg.ret, ret);
+		if (!ret)
+			return  -EIO;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(rproc_tee_start);
+
+int rproc_tee_stop(struct rproc *rproc)
+{
+	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
+	struct rproc_tee *trproc = rproc->rproc_tee_itf;
+	struct tee_ioctl_invoke_arg arg;
+	int ret;
+
+	if (!trproc)
+		return -EINVAL;
+
+	rproc_tee_prepare_args(trproc, TA_RPROC_FW_CMD_STOP_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_FW_CMD_STOP_FW invoke failed TEE err: %x, ret:%x\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)},
+	{}
+};
+
+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;
+	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 (!rproc_tee_ctx)
+		return -EPROBE_DEFER;
+
+	/* Prevent rproc tee module from being removed */
+	if (!try_module_get(THIS_MODULE)) {
+		dev_err(rproc_tee_ctx->dev, "can't get owner\n");
+		return -ENODEV;
+	}
+
+	trproc =  devm_kzalloc(dev, sizeof(*trproc), GFP_KERNEL);
+	if (!trproc) {
+		ret = -ENOMEM;
+		goto module_put;
+	}
+
+	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 module_put;
+	}
+
+	trproc->parent = dev;
+	trproc->rproc_id = rproc_id;
+	trproc->session_id = sess_arg.session;
+
+	trproc->rproc = rproc;
+	rproc->rproc_tee_itf = trproc;
+
+	list_add_tail(&trproc->node, &rproc_tee_ctx->sessions);
+
+	return 0;
+
+module_put:
+	module_put(THIS_MODULE);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(rproc_tee_register);
+
+int rproc_tee_unregister(struct rproc *rproc)
+{
+	struct rproc_tee *trproc = rproc->rproc_tee_itf;
+	int ret;
+
+	if (!rproc->rproc_tee_itf)
+		return -ENODEV;
+
+	ret = tee_client_close_session(rproc_tee_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->rproc_tee_itf = NULL;
+
+	module_put(THIS_MODULE);
+
+	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;
+	int ret;
+
+	/* 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);
+
+	rproc_tee_ctx = devm_kzalloc(dev, sizeof(*rproc_tee_ctx), GFP_KERNEL);
+	if (!rproc_tee_ctx) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	rproc_tee_ctx->dev = dev;
+	rproc_tee_ctx->tee_ctx = tee_ctx;
+	INIT_LIST_HEAD(&rproc_tee_ctx->sessions);
+
+	return 0;
+err:
+	tee_client_close_context(tee_ctx);
+
+	return ret;
+}
+
+static int rproc_tee_remove(struct device *dev)
+{
+	struct rproc_tee *entry, *tmp;
+
+	list_for_each_entry_safe(entry, tmp, &rproc_tee_ctx->sessions, node) {
+		tee_client_close_session(rproc_tee_ctx->tee_ctx, entry->session_id);
+		list_del(&entry->node);
+		kfree(entry);
+	}
+
+	tee_client_close_context(rproc_tee_ctx->tee_ctx);
+
+	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.h b/include/linux/remoteproc.h
index 8fd0d7f63c8e..2e0ddcb2d792 100644
--- a/include/linux/remoteproc.h
+++ b/include/linux/remoteproc.h
@@ -503,6 +503,8 @@ enum rproc_features {
 	RPROC_MAX_FEATURES,
 };
 
+struct rproc_tee;
+
 /**
  * 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
+ * @rproc_tee_itf: 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 rproc_tee *rproc_tee_itf;
 };
 
 /**
diff --git a/include/linux/remoteproc_tee.h b/include/linux/remoteproc_tee.h
new file mode 100644
index 000000000000..9b498a8eff4d
--- /dev/null
+++ b/include/linux/remoteproc_tee.h
@@ -0,0 +1,105 @@
+/* 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 - 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
+ */
+struct rproc_tee {
+	struct list_head node;
+	struct rproc *rproc;
+	struct device *parent;
+	u32 rproc_id;
+	u32 session_id;
+};
+
+#if IS_REACHABLE(CONFIG_REMOTEPROC_TEE)
+
+int rproc_tee_register(struct device *dev, struct rproc *rproc, unsigned int rproc_id);
+int rproc_tee_unregister(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 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 */
-- 
2.25.1
Re: [PATCH v13 2/7] remoteproc: Add TEE support
Posted by Mathieu Poirier 1 week, 2 days ago
On Mon, Nov 04, 2024 at 02:35:10PM +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 driver offers a client
> interface to load a firmware by the secure part.
> This firmware could be authenticated by the secure trusted application.
> 
> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
> ---
> Updates from version V11:
> - rename structures, functions, and variables from "tee_rproc_xxx" to
>   "rproc_tee_xxx",
> - update rproc_tee_register to return an error instead of
>   "struct rproc_tee *" pointer,
> - update rproc_tee_unregister argument from "struct rproc_tee *trproc"
>   to "struct rproc *rproc",
> - reword MODULE_DESCRIPTION.
> ---
>  drivers/remoteproc/Kconfig          |  10 +
>  drivers/remoteproc/Makefile         |   1 +
>  drivers/remoteproc/remoteproc_tee.c | 510 ++++++++++++++++++++++++++++
>  include/linux/remoteproc.h          |   4 +
>  include/linux/remoteproc_tee.h      | 105 ++++++
>  5 files changed, 630 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 955e4e38477e..d0284220a194 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
> +	tristate "Remoteproc support by a TEE application"

Tristate?  Didn't we agree this would be either compiled in or out, but not as a
module?

> +	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.
> +
> +	  It's safe to say N if you don't want to use remoteproc 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..f258b9304daf
> --- /dev/null
> +++ b/drivers/remoteproc/remoteproc_tee.c
> @@ -0,0 +1,510 @@
> +// 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/remoteproc.h>
> +#include <linux/remoteproc_tee.h>
> +#include <linux/slab.h>
> +#include <linux/tee_drv.h>
> +
> +#define MAX_TEE_PARAM_ARRAY_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
> +
> +/*
> + * 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 (A_RPROC_CMD_LOAD_FW) and the starting of the remote

s/A_RPROC_CMD_LOAD_FW/TA_RPROC_CMD_LOAD_FW

> + * 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;
> +};
> +
> +static struct rproc_tee_context *rproc_tee_ctx;
> +
> +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,
> +	};
> +}
> +
> +void rproc_tee_release_fw(struct rproc *rproc)
> +{
> +	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
> +	struct rproc_tee *trproc = rproc->rproc_tee_itf;
> +	struct tee_ioctl_invoke_arg arg;
> +	int ret;
> +
> +	if (!rproc) {
> +		ret = -EINVAL;
> +		goto out;
> +	}
> +
> +	/*
> +	 * 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) {
> +		ret = -EBUSY;
> +		goto out;
> +	}
> +
> +	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:%x\n",
> +			arg.ret, ret);
> +		ret = -EIO;
> +	}
> +
> +out:
> +	if (ret)
> +		/* Unexpected state without solution to come back in a stable state */
> +		dev_err(rproc_tee_ctx->dev, "Failed to release TEE remoteproc firmware: %d\n", ret);
> +}
> +EXPORT_SYMBOL_GPL(rproc_tee_release_fw);
> +
> +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->rproc_tee_itf;
> +	struct tee_ioctl_invoke_arg arg;
> +	struct tee_shm *fw_shm;
> +	int ret;
> +
> +	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:%x\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->rproc_tee_itf;
> +	struct tee_ioctl_invoke_arg arg;
> +	int ret;
> +
> +	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:%x\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;
> +}
> +
> +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;
> +
> +	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 (IS_ERR_OR_NULL(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);
> +
> +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);
> +
> +int rproc_tee_start(struct rproc *rproc)
> +{
> +	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
> +	struct rproc_tee *trproc = rproc->rproc_tee_itf;
> +	struct tee_ioctl_invoke_arg arg;
> +	int ret = 0;
> +
> +	if (!trproc)
> +		return -EINVAL;
> +
> +	rproc_tee_prepare_args(trproc, TA_RPROC_FW_CMD_START_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_FW_CMD_START_FW invoke failed TEE err: %x, ret:%x\n",
> +			arg.ret, ret);
> +		if (!ret)
> +			return  -EIO;
> +	}
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(rproc_tee_start);
> +
> +int rproc_tee_stop(struct rproc *rproc)
> +{
> +	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
> +	struct rproc_tee *trproc = rproc->rproc_tee_itf;
> +	struct tee_ioctl_invoke_arg arg;
> +	int ret;
> +
> +	if (!trproc)
> +		return -EINVAL;
> +
> +	rproc_tee_prepare_args(trproc, TA_RPROC_FW_CMD_STOP_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_FW_CMD_STOP_FW invoke failed TEE err: %x, ret:%x\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)},
> +	{}
> +};
> +
> +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;
> +	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 (!rproc_tee_ctx)
> +		return -EPROBE_DEFER;
> +
> +	/* Prevent rproc tee module from being removed */
> +	if (!try_module_get(THIS_MODULE)) {
> +		dev_err(rproc_tee_ctx->dev, "can't get owner\n");
> +		return -ENODEV;
> +	}
> +
> +	trproc =  devm_kzalloc(dev, sizeof(*trproc), GFP_KERNEL);
> +	if (!trproc) {
> +		ret = -ENOMEM;
> +		goto module_put;
> +	}
> +
> +	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 module_put;
> +	}
> +
> +	trproc->parent = dev;
> +	trproc->rproc_id = rproc_id;
> +	trproc->session_id = sess_arg.session;
> +
> +	trproc->rproc = rproc;
> +	rproc->rproc_tee_itf = trproc;
> +
> +	list_add_tail(&trproc->node, &rproc_tee_ctx->sessions);
> +
> +	return 0;
> +
> +module_put:
> +	module_put(THIS_MODULE);
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(rproc_tee_register);
> +
> +int rproc_tee_unregister(struct rproc *rproc)
> +{
> +	struct rproc_tee *trproc = rproc->rproc_tee_itf;
> +	int ret;
> +
> +	if (!rproc->rproc_tee_itf)
> +		return -ENODEV;
> +
> +	ret = tee_client_close_session(rproc_tee_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->rproc_tee_itf = NULL;
> +
> +	module_put(THIS_MODULE);
> +
> +	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;
> +	int ret;
> +
> +	/* 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);
> +
> +	rproc_tee_ctx = devm_kzalloc(dev, sizeof(*rproc_tee_ctx), GFP_KERNEL);
> +	if (!rproc_tee_ctx) {
> +		ret = -ENOMEM;
> +		goto err;
> +	}
> +
> +	rproc_tee_ctx->dev = dev;
> +	rproc_tee_ctx->tee_ctx = tee_ctx;
> +	INIT_LIST_HEAD(&rproc_tee_ctx->sessions);
> +
> +	return 0;
> +err:
> +	tee_client_close_context(tee_ctx);
> +
> +	return ret;
> +}
> +
> +static int rproc_tee_remove(struct device *dev)
> +{
> +	struct rproc_tee *entry, *tmp;
> +
> +	list_for_each_entry_safe(entry, tmp, &rproc_tee_ctx->sessions, node) {
> +		tee_client_close_session(rproc_tee_ctx->tee_ctx, entry->session_id);
> +		list_del(&entry->node);
> +		kfree(entry);
> +	}
> +
> +	tee_client_close_context(rproc_tee_ctx->tee_ctx);
> +
> +	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.h b/include/linux/remoteproc.h
> index 8fd0d7f63c8e..2e0ddcb2d792 100644
> --- a/include/linux/remoteproc.h
> +++ b/include/linux/remoteproc.h
> @@ -503,6 +503,8 @@ enum rproc_features {
>  	RPROC_MAX_FEATURES,
>  };
>  
> +struct rproc_tee;
> +
>  /**
>   * 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
> + * @rproc_tee_itf: 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 rproc_tee *rproc_tee_itf;
>  };
>  
>  /**
> diff --git a/include/linux/remoteproc_tee.h b/include/linux/remoteproc_tee.h
> new file mode 100644
> index 000000000000..9b498a8eff4d
> --- /dev/null
> +++ b/include/linux/remoteproc_tee.h
> @@ -0,0 +1,105 @@
> +/* 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 - 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
> + */
> +struct rproc_tee {
> +	struct list_head node;
> +	struct rproc *rproc;
> +	struct device *parent;
> +	u32 rproc_id;
> +	u32 session_id;
> +};
> +
> +#if IS_REACHABLE(CONFIG_REMOTEPROC_TEE)
> +
> +int rproc_tee_register(struct device *dev, struct rproc *rproc, unsigned int rproc_id);
> +int rproc_tee_unregister(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 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 */
> -- 
> 2.25.1
>
Re: [PATCH v13 2/7] remoteproc: Add TEE support
Posted by Arnaud POULIQUEN 1 week, 2 days ago
Hello Mathieu

On 11/14/24 18:59, Mathieu Poirier wrote:
> On Mon, Nov 04, 2024 at 02:35:10PM +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 driver offers a client
>> interface to load a firmware by the secure part.
>> This firmware could be authenticated by the secure trusted application.
>>
>> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
>> ---
>> Updates from version V11:
>> - rename structures, functions, and variables from "tee_rproc_xxx" to
>>   "rproc_tee_xxx",
>> - update rproc_tee_register to return an error instead of
>>   "struct rproc_tee *" pointer,
>> - update rproc_tee_unregister argument from "struct rproc_tee *trproc"
>>   to "struct rproc *rproc",
>> - reword MODULE_DESCRIPTION.
>> ---
>>  drivers/remoteproc/Kconfig          |  10 +
>>  drivers/remoteproc/Makefile         |   1 +
>>  drivers/remoteproc/remoteproc_tee.c | 510 ++++++++++++++++++++++++++++
>>  include/linux/remoteproc.h          |   4 +
>>  include/linux/remoteproc_tee.h      | 105 ++++++
>>  5 files changed, 630 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 955e4e38477e..d0284220a194 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
>> +	tristate "Remoteproc support by a TEE application"
> 
> Tristate?  Didn't we agree this would be either compiled in or out, but not as a
> module?

It was built-in because we needed to build it with the remoteproc core. With the
introduction of rproc->ops->release_fw, it is now independent and can be built
as a module (OPTEE config is also in tristate).

That said, I can limit it to the boolean configuration if that makes more sense
to you.

Thanks,
Arnaud



> 
>> +	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.
>> +
>> +	  It's safe to say N if you don't want to use remoteproc 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..f258b9304daf
>> --- /dev/null
>> +++ b/drivers/remoteproc/remoteproc_tee.c
>> @@ -0,0 +1,510 @@
>> +// 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/remoteproc.h>
>> +#include <linux/remoteproc_tee.h>
>> +#include <linux/slab.h>
>> +#include <linux/tee_drv.h>
>> +
>> +#define MAX_TEE_PARAM_ARRAY_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
>> +
>> +/*
>> + * 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 (A_RPROC_CMD_LOAD_FW) and the starting of the remote
> 
> s/A_RPROC_CMD_LOAD_FW/TA_RPROC_CMD_LOAD_FW
> 
>> + * 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;
>> +};
>> +
>> +static struct rproc_tee_context *rproc_tee_ctx;
>> +
>> +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,
>> +	};
>> +}
>> +
>> +void rproc_tee_release_fw(struct rproc *rproc)
>> +{
>> +	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
>> +	struct rproc_tee *trproc = rproc->rproc_tee_itf;
>> +	struct tee_ioctl_invoke_arg arg;
>> +	int ret;
>> +
>> +	if (!rproc) {
>> +		ret = -EINVAL;
>> +		goto out;
>> +	}
>> +
>> +	/*
>> +	 * 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) {
>> +		ret = -EBUSY;
>> +		goto out;
>> +	}
>> +
>> +	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:%x\n",
>> +			arg.ret, ret);
>> +		ret = -EIO;
>> +	}
>> +
>> +out:
>> +	if (ret)
>> +		/* Unexpected state without solution to come back in a stable state */
>> +		dev_err(rproc_tee_ctx->dev, "Failed to release TEE remoteproc firmware: %d\n", ret);
>> +}
>> +EXPORT_SYMBOL_GPL(rproc_tee_release_fw);
>> +
>> +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->rproc_tee_itf;
>> +	struct tee_ioctl_invoke_arg arg;
>> +	struct tee_shm *fw_shm;
>> +	int ret;
>> +
>> +	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:%x\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->rproc_tee_itf;
>> +	struct tee_ioctl_invoke_arg arg;
>> +	int ret;
>> +
>> +	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:%x\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;
>> +}
>> +
>> +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;
>> +
>> +	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 (IS_ERR_OR_NULL(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);
>> +
>> +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);
>> +
>> +int rproc_tee_start(struct rproc *rproc)
>> +{
>> +	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
>> +	struct rproc_tee *trproc = rproc->rproc_tee_itf;
>> +	struct tee_ioctl_invoke_arg arg;
>> +	int ret = 0;
>> +
>> +	if (!trproc)
>> +		return -EINVAL;
>> +
>> +	rproc_tee_prepare_args(trproc, TA_RPROC_FW_CMD_START_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_FW_CMD_START_FW invoke failed TEE err: %x, ret:%x\n",
>> +			arg.ret, ret);
>> +		if (!ret)
>> +			return  -EIO;
>> +	}
>> +
>> +	return 0;
>> +}
>> +EXPORT_SYMBOL_GPL(rproc_tee_start);
>> +
>> +int rproc_tee_stop(struct rproc *rproc)
>> +{
>> +	struct tee_param param[MAX_TEE_PARAM_ARRAY_MEMBER];
>> +	struct rproc_tee *trproc = rproc->rproc_tee_itf;
>> +	struct tee_ioctl_invoke_arg arg;
>> +	int ret;
>> +
>> +	if (!trproc)
>> +		return -EINVAL;
>> +
>> +	rproc_tee_prepare_args(trproc, TA_RPROC_FW_CMD_STOP_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_FW_CMD_STOP_FW invoke failed TEE err: %x, ret:%x\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)},
>> +	{}
>> +};
>> +
>> +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;
>> +	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 (!rproc_tee_ctx)
>> +		return -EPROBE_DEFER;
>> +
>> +	/* Prevent rproc tee module from being removed */
>> +	if (!try_module_get(THIS_MODULE)) {
>> +		dev_err(rproc_tee_ctx->dev, "can't get owner\n");
>> +		return -ENODEV;
>> +	}
>> +
>> +	trproc =  devm_kzalloc(dev, sizeof(*trproc), GFP_KERNEL);
>> +	if (!trproc) {
>> +		ret = -ENOMEM;
>> +		goto module_put;
>> +	}
>> +
>> +	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 module_put;
>> +	}
>> +
>> +	trproc->parent = dev;
>> +	trproc->rproc_id = rproc_id;
>> +	trproc->session_id = sess_arg.session;
>> +
>> +	trproc->rproc = rproc;
>> +	rproc->rproc_tee_itf = trproc;
>> +
>> +	list_add_tail(&trproc->node, &rproc_tee_ctx->sessions);
>> +
>> +	return 0;
>> +
>> +module_put:
>> +	module_put(THIS_MODULE);
>> +	return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(rproc_tee_register);
>> +
>> +int rproc_tee_unregister(struct rproc *rproc)
>> +{
>> +	struct rproc_tee *trproc = rproc->rproc_tee_itf;
>> +	int ret;
>> +
>> +	if (!rproc->rproc_tee_itf)
>> +		return -ENODEV;
>> +
>> +	ret = tee_client_close_session(rproc_tee_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->rproc_tee_itf = NULL;
>> +
>> +	module_put(THIS_MODULE);
>> +
>> +	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;
>> +	int ret;
>> +
>> +	/* 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);
>> +
>> +	rproc_tee_ctx = devm_kzalloc(dev, sizeof(*rproc_tee_ctx), GFP_KERNEL);
>> +	if (!rproc_tee_ctx) {
>> +		ret = -ENOMEM;
>> +		goto err;
>> +	}
>> +
>> +	rproc_tee_ctx->dev = dev;
>> +	rproc_tee_ctx->tee_ctx = tee_ctx;
>> +	INIT_LIST_HEAD(&rproc_tee_ctx->sessions);
>> +
>> +	return 0;
>> +err:
>> +	tee_client_close_context(tee_ctx);
>> +
>> +	return ret;
>> +}
>> +
>> +static int rproc_tee_remove(struct device *dev)
>> +{
>> +	struct rproc_tee *entry, *tmp;
>> +
>> +	list_for_each_entry_safe(entry, tmp, &rproc_tee_ctx->sessions, node) {
>> +		tee_client_close_session(rproc_tee_ctx->tee_ctx, entry->session_id);
>> +		list_del(&entry->node);
>> +		kfree(entry);
>> +	}
>> +
>> +	tee_client_close_context(rproc_tee_ctx->tee_ctx);
>> +
>> +	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.h b/include/linux/remoteproc.h
>> index 8fd0d7f63c8e..2e0ddcb2d792 100644
>> --- a/include/linux/remoteproc.h
>> +++ b/include/linux/remoteproc.h
>> @@ -503,6 +503,8 @@ enum rproc_features {
>>  	RPROC_MAX_FEATURES,
>>  };
>>  
>> +struct rproc_tee;
>> +
>>  /**
>>   * 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
>> + * @rproc_tee_itf: 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 rproc_tee *rproc_tee_itf;
>>  };
>>  
>>  /**
>> diff --git a/include/linux/remoteproc_tee.h b/include/linux/remoteproc_tee.h
>> new file mode 100644
>> index 000000000000..9b498a8eff4d
>> --- /dev/null
>> +++ b/include/linux/remoteproc_tee.h
>> @@ -0,0 +1,105 @@
>> +/* 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 - 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
>> + */
>> +struct rproc_tee {
>> +	struct list_head node;
>> +	struct rproc *rproc;
>> +	struct device *parent;
>> +	u32 rproc_id;
>> +	u32 session_id;
>> +};
>> +
>> +#if IS_REACHABLE(CONFIG_REMOTEPROC_TEE)
>> +
>> +int rproc_tee_register(struct device *dev, struct rproc *rproc, unsigned int rproc_id);
>> +int rproc_tee_unregister(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 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 */
>> -- 
>> 2.25.1
>>