[PATCH 1/4] remoteproc: Add TEE support

From: Arnaud Pouliquen
Date: Mon Jan 15 2024 - 08:55:01 EST


From: Arnaud Pouliquen <arnaud.pouliquen@xxxxxx>

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

Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxx>
---
drivers/remoteproc/Kconfig | 9 +
drivers/remoteproc/Makefile | 1 +
drivers/remoteproc/tee_remoteproc.c | 393 ++++++++++++++++++++++++++++
include/linux/tee_remoteproc.h | 99 +++++++
4 files changed, 502 insertions(+)
create mode 100644 drivers/remoteproc/tee_remoteproc.c
create mode 100644 include/linux/tee_remoteproc.h

diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig
index 48845dc8fa85..85299606806c 100644
--- a/drivers/remoteproc/Kconfig
+++ b/drivers/remoteproc/Kconfig
@@ -365,6 +365,15 @@ config XLNX_R5_REMOTEPROC

It's safe to say N if not interested in using RPU r5f cores.

+
+config TEE_REMOTEPROC
+ tristate "trusted firmware support by a TEE application"
+ depends on OPTEE
+ help
+ Support for trusted remote processors firmware. The firmware
+ authentication and/or decryption are managed by a trusted application.
+ This can be either built-in or a loadable module.
+
endif # REMOTEPROC

endmenu
diff --git a/drivers/remoteproc/Makefile b/drivers/remoteproc/Makefile
index 91314a9b43ce..fa8daebce277 100644
--- a/drivers/remoteproc/Makefile
+++ b/drivers/remoteproc/Makefile
@@ -36,6 +36,7 @@ obj-$(CONFIG_RCAR_REMOTEPROC) += rcar_rproc.o
obj-$(CONFIG_ST_REMOTEPROC) += st_remoteproc.o
obj-$(CONFIG_ST_SLIM_REMOTEPROC) += st_slim_rproc.o
obj-$(CONFIG_STM32_RPROC) += stm32_rproc.o
+obj-$(CONFIG_TEE_REMOTEPROC) += tee_remoteproc.o
obj-$(CONFIG_TI_K3_DSP_REMOTEPROC) += ti_k3_dsp_remoteproc.o
obj-$(CONFIG_TI_K3_R5_REMOTEPROC) += ti_k3_r5_remoteproc.o
obj-$(CONFIG_XLNX_R5_REMOTEPROC) += xlnx_r5_remoteproc.o
diff --git a/drivers/remoteproc/tee_remoteproc.c b/drivers/remoteproc/tee_remoteproc.c
new file mode 100644
index 000000000000..d089087eb1f6
--- /dev/null
+++ b/drivers/remoteproc/tee_remoteproc.c
@@ -0,0 +1,393 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) STMicroelectronics 2023 - All Rights Reserved
+ * Author: Arnaud Pouliquen <arnaud.pouliquen@xxxxxx>
+ */
+
+#include <linux/firmware.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of_reserved_mem.h>
+#include <linux/remoteproc.h>
+#include <linux/slab.h>
+#include <linux/tee_drv.h>
+#include <linux/tee_remoteproc.h>
+
+#include "remoteproc_internal.h"
+
+#define MAX_TEE_PARAM_ARRY_MEMBER 4
+
+/*
+ * Authentication of the firmware and load in the remote processor memory
+ *
+ * [in] params[0].value.a: unique 32bit identifier of the remote processor
+ * [in] params[1].memref: buffer containing the image of the buffer
+ */
+#define TA_RPROC_FW_CMD_LOAD_FW 1
+
+/*
+ * Start the remote processor
+ *
+ * [in] params[0].value.a: unique 32bit identifier of the remote processor
+ */
+#define TA_RPROC_FW_CMD_START_FW 2
+
+/*
+ * Stop the remote processor
+ *
+ * [in] params[0].value.a: unique 32bit identifier of the remote processor
+ */
+#define TA_RPROC_FW_CMD_STOP_FW 3
+
+/*
+ * Return the address of the resource table, or 0 if not found
+ * No check is done to verify that the address returned is accessible by
+ * the non secure context. If the resource table is loaded in a protected
+ * memory the access by the non secure context will lead to a data abort.
+ *
+ * [in] params[0].value.a: unique 32bit identifier of the remote processor
+ * [out] params[1].value.a: 32bit LSB resource table memory address
+ * [out] params[1].value.b: 32bit MSB resource table memory address
+ * [out] params[2].value.a: 32bit LSB resource table memory size
+ * [out] params[2].value.b: 32bit MSB resource table memory size
+ */
+#define TA_RPROC_FW_CMD_GET_RSC_TABLE 4
+
+/*
+ * Return the address of the core dump
+ *
+ * [in] params[0].value.a: unique 32bit identifier of the remote processor
+ * [out] params[1].memref: address of the core dump image if exist,
+ * else return Null
+ */
+#define TA_RPROC_FW_CMD_GET_COREDUMP 5
+
+struct tee_rproc_mem {
+ char name[20];
+ void __iomem *cpu_addr;
+ phys_addr_t bus_addr;
+ u32 dev_addr;
+ size_t size;
+};
+
+struct tee_rproc_context {
+ struct list_head sessions;
+ struct tee_context *tee_ctx;
+ struct device *dev;
+};
+
+struct tee_rproc_context *tee_rproc_ctx;
+
+static void prepare_args(struct tee_rproc *trproc, int cmd, struct tee_ioctl_invoke_arg *arg,
+ struct tee_param *param, unsigned int num_params)
+{
+ memset(arg, 0, sizeof(*arg));
+ memset(param, 0, MAX_TEE_PARAM_ARRY_MEMBER * sizeof(*param));
+
+ arg->func = cmd;
+ arg->session = trproc->session_id;
+ arg->num_params = num_params + 1;
+
+ param[0] = (struct tee_param) {
+ .attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT,
+ .u.value.a = trproc->rproc_id,
+ };
+}
+
+int tee_rproc_load_fw(struct tee_rproc *trproc, const struct firmware *fw)
+{
+ struct tee_ioctl_invoke_arg arg;
+ struct tee_param param[MAX_TEE_PARAM_ARRY_MEMBER];
+ struct tee_shm *fw_shm;
+ int ret;
+
+ fw_shm = tee_shm_register_kernel_buf(tee_rproc_ctx->tee_ctx, (void *)fw->data, fw->size);
+ if (IS_ERR(fw_shm))
+ return PTR_ERR(fw_shm);
+
+ prepare_args(trproc, TA_RPROC_FW_CMD_LOAD_FW, &arg, param, 1);
+
+ /* Provide the address of the firmware image */
+ param[1] = (struct tee_param) {
+ .attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT,
+ .u.memref = {
+ .shm = fw_shm,
+ .size = fw->size,
+ .shm_offs = 0,
+ },
+ };
+
+ ret = tee_client_invoke_func(tee_rproc_ctx->tee_ctx, &arg, param);
+ if (ret < 0 || arg.ret != 0) {
+ dev_err(tee_rproc_ctx->dev,
+ "TA_RPROC_FW_CMD_LOAD_FW invoke failed TEE err: %x, ret:%x\n",
+ arg.ret, ret);
+ if (!ret)
+ ret = -EIO;
+ }
+
+ tee_shm_free(fw_shm);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(tee_rproc_load_fw);
+
+int rproc_tee_get_rsc_table(struct tee_rproc *trproc)
+{
+ struct tee_ioctl_invoke_arg arg;
+ struct tee_param param[MAX_TEE_PARAM_ARRY_MEMBER];
+ struct rproc *rproc = trproc->rproc;
+ size_t rsc_size;
+ int ret;
+
+ prepare_args(trproc, TA_RPROC_FW_CMD_GET_RSC_TABLE, &arg, param, 2);
+
+ param[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT;
+ param[2].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT;
+
+ ret = tee_client_invoke_func(tee_rproc_ctx->tee_ctx, &arg, param);
+ if (ret < 0 || arg.ret != 0) {
+ dev_err(tee_rproc_ctx->dev,
+ "TA_RPROC_FW_CMD_GET_RSC_TABLE invoke failed TEE err: %x, ret:%x\n",
+ arg.ret, ret);
+ return -EIO;
+ }
+
+ rsc_size = param[2].u.value.a;
+
+ /* If the size is null no resource table defined in the image */
+ if (!rsc_size)
+ return 0;
+
+ /* Store the resource table address that would be updated by the remote core . */
+ trproc->rsc_va = ioremap_wc(param[1].u.value.a, rsc_size);
+ if (IS_ERR_OR_NULL(trproc->rsc_va)) {
+ dev_err(tee_rproc_ctx->dev, "Unable to map memory region: %lld+%zx\n",
+ param[1].u.value.a, rsc_size);
+ trproc->rsc_va = NULL;
+ return -ENOMEM;
+ }
+
+ /*
+ * A cached table is requested as the physical address is not mapped yet
+ * but remoteproc needs to parse the table for resources.
+ */
+ rproc->cached_table = kmemdup(trproc->rsc_va, rsc_size, GFP_KERNEL);
+ if (!rproc->cached_table)
+ return -ENOMEM;
+
+ rproc->table_ptr = rproc->cached_table;
+ rproc->table_sz = rsc_size;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(rproc_tee_get_rsc_table);
+
+struct resource_table *tee_rproc_get_loaded_rsc_table(struct tee_rproc *trproc)
+{
+ return (struct resource_table *)trproc->rsc_va;
+}
+EXPORT_SYMBOL_GPL(tee_rproc_get_loaded_rsc_table);
+
+int tee_rproc_start(struct tee_rproc *trproc)
+{
+ struct tee_ioctl_invoke_arg arg;
+ struct tee_param param[MAX_TEE_PARAM_ARRY_MEMBER];
+ int ret;
+
+ prepare_args(trproc, TA_RPROC_FW_CMD_START_FW, &arg, param, 0);
+
+ ret = tee_client_invoke_func(tee_rproc_ctx->tee_ctx, &arg, param);
+ if (ret < 0 || arg.ret != 0) {
+ dev_err(tee_rproc_ctx->dev,
+ "TA_RPROC_FW_CMD_START_FW invoke failed TEE err: %x, ret:%x\n",
+ arg.ret, ret);
+ if (!ret)
+ ret = -EIO;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(tee_rproc_start);
+
+int tee_rproc_stop(struct tee_rproc *trproc)
+{
+ struct tee_ioctl_invoke_arg arg;
+ struct tee_param param[MAX_TEE_PARAM_ARRY_MEMBER];
+ int ret;
+
+ prepare_args(trproc, TA_RPROC_FW_CMD_STOP_FW, &arg, param, 0);
+
+ ret = tee_client_invoke_func(tee_rproc_ctx->tee_ctx, &arg, param);
+ if (ret < 0 || arg.ret != 0) {
+ dev_err(tee_rproc_ctx->dev,
+ "TA_RPROC_FW_CMD_STOP_FW invoke failed TEE err: %x, ret:%x\n",
+ arg.ret, ret);
+ if (!ret)
+ ret = -EIO;
+ }
+ if (trproc->rsc_va)
+ iounmap(trproc->rsc_va);
+ trproc->rsc_va = NULL;
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(tee_rproc_stop);
+
+static const struct tee_client_device_id stm32_tee_rproc_id_table[] = {
+ {UUID_INIT(0x80a4c275, 0x0a47, 0x4905,
+ 0x82, 0x85, 0x14, 0x86, 0xa9, 0x77, 0x1a, 0x08)},
+ {}
+};
+
+struct tee_rproc *tee_rproc_register(struct device *dev, unsigned int rproc_id)
+{
+ struct tee_client_device *rproc_tee_device;
+ struct tee_ioctl_open_session_arg sess_arg;
+ struct tee_param param[MAX_TEE_PARAM_ARRY_MEMBER];
+ struct tee_rproc *trproc;
+ int ret;
+
+ /*
+ * The device is not probed by the TEE bus. We ignore the reason (bus could be not yet
+ * probed or service not available in the secure firmware)
+ * Assumption here is that the TEE bus is not probed.
+ */
+ if (!tee_rproc_ctx)
+ return ERR_PTR(-EPROBE_DEFER);
+
+ trproc = devm_kzalloc(dev, sizeof(*trproc), GFP_KERNEL);
+ if (!trproc)
+ return ERR_PTR(-ENOMEM);
+
+ rproc_tee_device = to_tee_client_device(tee_rproc_ctx->dev);
+ memset(&sess_arg, 0, sizeof(sess_arg));
+
+ /* Open session with rproc_tee load the OP-TEE Trusted Application */
+ memcpy(sess_arg.uuid, rproc_tee_device->id.uuid.b, TEE_IOCTL_UUID_LEN);
+
+ sess_arg.clnt_login = TEE_IOCTL_LOGIN_REE_KERNEL;
+ sess_arg.num_params = 1;
+
+ param[0] = (struct tee_param) {
+ .attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT,
+ .u.value.a = rproc_id,
+ };
+
+ ret = tee_client_open_session(tee_rproc_ctx->tee_ctx, &sess_arg, param);
+ if (ret < 0 || sess_arg.ret != 0) {
+ dev_err(dev, "tee_client_open_session failed, err: %x\n", sess_arg.ret);
+ return ERR_PTR(-EINVAL);
+ }
+
+ trproc->parent = dev;
+ trproc->rproc_id = rproc_id;
+ trproc->session_id = sess_arg.session;
+
+ list_add_tail(&trproc->node, &tee_rproc_ctx->sessions);
+
+ return trproc;
+}
+EXPORT_SYMBOL_GPL(tee_rproc_register);
+
+int tee_rproc_unregister(struct tee_rproc *trproc)
+{
+ int ret;
+
+ if (!tee_rproc_ctx)
+ return -ENODEV;
+
+ ret = tee_client_close_session(tee_rproc_ctx->tee_ctx, trproc->session_id);
+ if (ret < 0)
+ dev_err(trproc->parent, "tee_client_close_session failed, err: %x\n", ret);
+
+ list_del(&trproc->node);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(tee_rproc_unregister);
+
+static int tee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
+{
+ /* Today we support only the OP-TEE, could be extend to other tees */
+ return (ver->impl_id == TEE_IMPL_ID_OPTEE);
+}
+
+static int tee_rproc_probe(struct device *dev)
+{
+ struct tee_context *tee_ctx;
+ int ret;
+
+ /* Only one RPROC OP-TEE device allowed */
+ if (tee_rproc_ctx) {
+ dev_err(dev, "An RPROC OP-TEE device was already initialized: only one allowed\n");
+ return -EBUSY;
+ }
+
+ /* Open context with TEE driver */
+ tee_ctx = tee_client_open_context(NULL, tee_ctx_match, NULL, NULL);
+ if (IS_ERR(tee_ctx))
+ return PTR_ERR(tee_ctx);
+
+ tee_rproc_ctx = devm_kzalloc(dev, sizeof(*tee_ctx), GFP_KERNEL);
+ if (!tee_ctx) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ tee_rproc_ctx->dev = dev;
+ tee_rproc_ctx->tee_ctx = tee_ctx;
+ INIT_LIST_HEAD(&tee_rproc_ctx->sessions);
+
+ return 0;
+err:
+ tee_client_close_context(tee_ctx);
+
+ return ret;
+}
+
+static int tee_rproc_remove(struct device *dev)
+{
+ struct tee_rproc *entry, *tmp;
+
+ list_for_each_entry_safe(entry, tmp, &tee_rproc_ctx->sessions, node) {
+ tee_client_close_session(tee_rproc_ctx->tee_ctx, entry->session_id);
+ list_del(&entry->node);
+ kfree(entry);
+ }
+
+ tee_client_close_context(tee_rproc_ctx->tee_ctx);
+
+ return 0;
+}
+
+MODULE_DEVICE_TABLE(tee, stm32_tee_rproc_id_table);
+
+static struct tee_client_driver tee_rproc_fw_driver = {
+ .id_table = stm32_tee_rproc_id_table,
+ .driver = {
+ .name = KBUILD_MODNAME,
+ .bus = &tee_bus_type,
+ .probe = tee_rproc_probe,
+ .remove = tee_rproc_remove,
+ },
+};
+
+static int __init tee_rproc_fw_mod_init(void)
+{
+ return driver_register(&tee_rproc_fw_driver.driver);
+}
+
+static void __exit tee_rproc_fw_mod_exit(void)
+{
+ driver_unregister(&tee_rproc_fw_driver.driver);
+}
+
+module_init(tee_rproc_fw_mod_init);
+module_exit(tee_rproc_fw_mod_exit);
+
+MODULE_DESCRIPTION(" TEE remote processor control driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/tee_remoteproc.h b/include/linux/tee_remoteproc.h
new file mode 100644
index 000000000000..0e11e5b8b524
--- /dev/null
+++ b/include/linux/tee_remoteproc.h
@@ -0,0 +1,99 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright(c) 2023 STMicroelectronics - All Rights Reserved
+ */
+
+#ifndef TEE_REMOTEPROC_H
+#define TEE_REMOTEPROC_H
+
+#include <linux/remoteproc.h>
+#include <linux/tee_drv.h>
+
+/**
+ * struct tee_rproc - TEE remoteproc structure
+ * @node: Reference in list
+ * @rproc: Remoteproc reference
+ * @parent: Parent device
+ * @rproc_id: Identifier of the target firmware
+ * @session_id: TEE session identifier
+ * @rsc_va: Resource table virtual address.
+ */
+struct tee_rproc {
+ struct list_head node;
+ struct rproc *rproc;
+ struct device *parent;
+ u32 rproc_id;
+ u32 session_id;
+ void *rsc_va;
+};
+
+#if IS_ENABLED(CONFIG_TEE_REMOTEPROC)
+
+struct tee_rproc *tee_rproc_register(struct device *dev, unsigned int rproc_id);
+int tee_rproc_unregister(struct tee_rproc *trproc);
+
+int tee_rproc_load_fw(struct tee_rproc *trproc, const struct firmware *fw);
+int rproc_tee_get_rsc_table(struct tee_rproc *trproc);
+struct resource_table *tee_rproc_get_loaded_rsc_table(struct tee_rproc *trproc);
+int tee_rproc_start(struct tee_rproc *trproc);
+int tee_rproc_stop(struct tee_rproc *trproc);
+
+#else
+
+static inline struct tee_rproc *tee_rproc_register(struct device *dev, unsigned int rproc_id)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline int tee_rproc_unregister(struct tee_rproc *trproc)
+{
+ /* This shouldn't be possible */
+ WARN_ON(1);
+
+ return 0;
+}
+
+static inline int tee_rproc_load_fw(struct tee_rproc *trproc,
+ const struct firmware *fw)
+{
+ /* This shouldn't be possible */
+ WARN_ON(1);
+
+ return 0;
+}
+
+static inline int tee_rproc_start(struct tee_rproc *trproc)
+{
+ /* This shouldn't be possible */
+ WARN_ON(1);
+
+ return 0;
+}
+
+static inline int tee_rproc_stop(struct tee_rproc *trproc)
+{
+ /* This shouldn't be possible */
+ WARN_ON(1);
+
+ return 0;
+}
+
+static inline int rproc_tee_get_rsc_table(struct tee_rproc *trproc)
+{
+ /* This shouldn't be possible */
+ WARN_ON(1);
+
+ return 0;
+}
+
+static inline struct resource_table *
+ tee_rproc_get_loaded_rsc_table(struct tee_rproc *trproc)
+{
+ /* This shouldn't be possible */
+ WARN_ON(1);
+
+ return NULL;
+}
+
+#endif /* CONFIG_TEE_REMOTEPROC */
+#endif /* TEE_REMOTEPROC_H */
--
2.25.1