1 files changed, 536 insertions, 0 deletions
diff --git a/drivers/tee/amdtee/core.c b/drivers/tee/amdtee/core.c
new file mode 100644
index 000000000..3c15f6a9e
--- /dev/null
+++ b/drivers/tee/amdtee/core.c
@@ -0,0 +1,536 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright 2019 Advanced Micro Devices, Inc.
+ */
+
+#include <linux/errno.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/device.h>
+#include <linux/tee_drv.h>
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/uaccess.h>
+#include <linux/firmware.h>
+#include "amdtee_private.h"
+#include "../tee_private.h"
+#include <linux/psp-tee.h>
+
+static struct amdtee_driver_data *drv_data;
+static DEFINE_MUTEX(session_list_mutex);
+
+static void amdtee_get_version(struct tee_device *teedev,
+			       struct tee_ioctl_version_data *vers)
+{
+	struct tee_ioctl_version_data v = {
+		.impl_id = TEE_IMPL_ID_AMDTEE,
+		.impl_caps = 0,
+		.gen_caps = TEE_GEN_CAP_GP,
+	};
+	*vers = v;
+}
+
+static int amdtee_open(struct tee_context *ctx)
+{
+	struct amdtee_context_data *ctxdata;
+
+	ctxdata = kzalloc(sizeof(*ctxdata), GFP_KERNEL);
+	if (!ctxdata)
+		return -ENOMEM;
+
+	INIT_LIST_HEAD(&ctxdata->sess_list);
+	INIT_LIST_HEAD(&ctxdata->shm_list);
+	mutex_init(&ctxdata->shm_mutex);
+
+	ctx->data = ctxdata;
+	return 0;
+}
+
+static void release_session(struct amdtee_session *sess)
+{
+	int i;
+
+	/* Close any open session */
+	for (i = 0; i < TEE_NUM_SESSIONS; ++i) {
+		/* Check if session entry 'i' is valid */
+		if (!test_bit(i, sess->sess_mask))
+			continue;
+
+		handle_close_session(sess->ta_handle, sess->session_info[i]);
+		handle_unload_ta(sess->ta_handle);
+	}
+
+	kfree(sess);
+}
+
+static void amdtee_release(struct tee_context *ctx)
+{
+	struct amdtee_context_data *ctxdata = ctx->data;
+
+	if (!ctxdata)
+		return;
+
+	while (true) {
+		struct amdtee_session *sess;
+
+		sess = list_first_entry_or_null(&ctxdata->sess_list,
+						struct amdtee_session,
+						list_node);
+
+		if (!sess)
+			break;
+
+		list_del(&sess->list_node);
+		release_session(sess);
+	}
+	mutex_destroy(&ctxdata->shm_mutex);
+	kfree(ctxdata);
+
+	ctx->data = NULL;
+}
+
+/**
+ * alloc_session() - Allocate a session structure
+ * @ctxdata:    TEE Context data structure
+ * @session:    Session ID for which 'struct amdtee_session' structure is to be
+ *              allocated.
+ *
+ * Scans the TEE context's session list to check if TA is already loaded in to
+ * TEE. If yes, returns the 'session' structure for that TA. Else allocates,
+ * initializes a new 'session' structure and adds it to context's session list.
+ *
+ * The caller must hold a mutex.
+ *
+ * Returns:
+ * 'struct amdtee_session *' on success and NULL on failure.
+ */
+static struct amdtee_session *alloc_session(struct amdtee_context_data *ctxdata,
+					    u32 session)
+{
+	struct amdtee_session *sess;
+	u32 ta_handle = get_ta_handle(session);
+
+	/* Scan session list to check if TA is already loaded in to TEE */
+	list_for_each_entry(sess, &ctxdata->sess_list, list_node)
+		if (sess->ta_handle == ta_handle) {
+			kref_get(&sess->refcount);
+			return sess;
+		}
+
+	/* Allocate a new session and add to list */
+	sess = kzalloc(sizeof(*sess), GFP_KERNEL);
+	if (sess) {
+		sess->ta_handle = ta_handle;
+		kref_init(&sess->refcount);
+		spin_lock_init(&sess->lock);
+		list_add(&sess->list_node, &ctxdata->sess_list);
+	}
+
+	return sess;
+}
+
+/* Requires mutex to be held */
+static struct amdtee_session *find_session(struct amdtee_context_data *ctxdata,
+					   u32 session)
+{
+	u32 ta_handle = get_ta_handle(session);
+	u32 index = get_session_index(session);
+	struct amdtee_session *sess;
+
+	if (index >= TEE_NUM_SESSIONS)
+		return NULL;
+
+	list_for_each_entry(sess, &ctxdata->sess_list, list_node)
+		if (ta_handle == sess->ta_handle &&
+		    test_bit(index, sess->sess_mask))
+			return sess;
+
+	return NULL;
+}
+
+u32 get_buffer_id(struct tee_shm *shm)
+{
+	struct amdtee_context_data *ctxdata = shm->ctx->data;
+	struct amdtee_shm_data *shmdata;
+	u32 buf_id = 0;
+
+	mutex_lock(&ctxdata->shm_mutex);
+	list_for_each_entry(shmdata, &ctxdata->shm_list, shm_node)
+		if (shmdata->kaddr == shm->kaddr) {
+			buf_id = shmdata->buf_id;
+			break;
+		}
+	mutex_unlock(&ctxdata->shm_mutex);
+
+	return buf_id;
+}
+
+static DEFINE_MUTEX(drv_mutex);
+static int copy_ta_binary(struct tee_context *ctx, void *ptr, void **ta,
+			  size_t *ta_size)
+{
+	const struct firmware *fw;
+	char fw_name[TA_PATH_MAX];
+	struct {
+		u32 lo;
+		u16 mid;
+		u16 hi_ver;
+		u8 seq_n[8];
+	} *uuid = ptr;
+	int n, rc = 0;
+
+	n = snprintf(fw_name, TA_PATH_MAX,
+		     "%s/%08x-%04x-%04x-%02x%02x%02x%02x%02x%02x%02x%02x.bin",
+		     TA_LOAD_PATH, uuid->lo, uuid->mid, uuid->hi_ver,
+		     uuid->seq_n[0], uuid->seq_n[1],
+		     uuid->seq_n[2], uuid->seq_n[3],
+		     uuid->seq_n[4], uuid->seq_n[5],
+		     uuid->seq_n[6], uuid->seq_n[7]);
+	if (n < 0 || n >= TA_PATH_MAX) {
+		pr_err("failed to get firmware name\n");
+		return -EINVAL;
+	}
+
+	mutex_lock(&drv_mutex);
+	n = request_firmware(&fw, fw_name, &ctx->teedev->dev);
+	if (n) {
+		pr_err("failed to load firmware %s\n", fw_name);
+		rc = -ENOMEM;
+		goto unlock;
+	}
+
+	*ta_size = roundup(fw->size, PAGE_SIZE);
+	*ta = (void *)__get_free_pages(GFP_KERNEL, get_order(*ta_size));
+	if (!*ta) {
+		pr_err("%s: get_free_pages failed\n", __func__);
+		rc = -ENOMEM;
+		goto rel_fw;
+	}
+
+	memcpy(*ta, fw->data, fw->size);
+rel_fw:
+	release_firmware(fw);
+unlock:
+	mutex_unlock(&drv_mutex);
+	return rc;
+}
+
+/* mutex must be held by caller */
+static void destroy_session(struct kref *ref)
+{
+	struct amdtee_session *sess = container_of(ref, struct amdtee_session,
+						   refcount);
+
+	list_del(&sess->list_node);
+	mutex_unlock(&session_list_mutex);
+	kfree(sess);
+}
+
+int amdtee_open_session(struct tee_context *ctx,
+			struct tee_ioctl_open_session_arg *arg,
+			struct tee_param *param)
+{
+	struct amdtee_context_data *ctxdata = ctx->data;
+	struct amdtee_session *sess = NULL;
+	u32 session_info, ta_handle;
+	size_t ta_size;
+	int rc, i;
+	void *ta;
+
+	if (arg->clnt_login != TEE_IOCTL_LOGIN_PUBLIC) {
+		pr_err("unsupported client login method\n");
+		return -EINVAL;
+	}
+
+	rc = copy_ta_binary(ctx, &arg->uuid[0], &ta, &ta_size);
+	if (rc) {
+		pr_err("failed to copy TA binary\n");
+		return rc;
+	}
+
+	/* Load the TA binary into TEE environment */
+	handle_load_ta(ta, ta_size, arg);
+	if (arg->ret != TEEC_SUCCESS)
+		goto out;
+
+	ta_handle = get_ta_handle(arg->session);
+
+	mutex_lock(&session_list_mutex);
+	sess = alloc_session(ctxdata, arg->session);
+	mutex_unlock(&session_list_mutex);
+
+	if (!sess) {
+		handle_unload_ta(ta_handle);
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	/* Open session with loaded TA */
+	handle_open_session(arg, &session_info, param);
+	if (arg->ret != TEEC_SUCCESS) {
+		pr_err("open_session failed %d\n", arg->ret);
+		handle_unload_ta(ta_handle);
+		kref_put_mutex(&sess->refcount, destroy_session,
+			       &session_list_mutex);
+		goto out;
+	}
+
+	/* Find an empty session index for the given TA */
+	spin_lock(&sess->lock);
+	i = find_first_zero_bit(sess->sess_mask, TEE_NUM_SESSIONS);
+	if (i < TEE_NUM_SESSIONS) {
+		sess->session_info[i] = session_info;
+		set_session_id(ta_handle, i, &arg->session);
+		set_bit(i, sess->sess_mask);
+	}
+	spin_unlock(&sess->lock);
+
+	if (i >= TEE_NUM_SESSIONS) {
+		pr_err("reached maximum session count %d\n", TEE_NUM_SESSIONS);
+		handle_close_session(ta_handle, session_info);
+		handle_unload_ta(ta_handle);
+		kref_put_mutex(&sess->refcount, destroy_session,
+			       &session_list_mutex);
+		rc = -ENOMEM;
+		goto out;
+	}
+
+out:
+	free_pages((u64)ta, get_order(ta_size));
+	return rc;
+}
+
+int amdtee_close_session(struct tee_context *ctx, u32 session)
+{
+	struct amdtee_context_data *ctxdata = ctx->data;
+	u32 i, ta_handle, session_info;
+	struct amdtee_session *sess;
+
+	pr_debug("%s: sid = 0x%x\n", __func__, session);
+
+	/*
+	 * Check that the session is valid and clear the session
+	 * usage bit
+	 */
+	mutex_lock(&session_list_mutex);
+	sess = find_session(ctxdata, session);
+	if (sess) {
+		ta_handle = get_ta_handle(session);
+		i = get_session_index(session);
+		session_info = sess->session_info[i];
+		spin_lock(&sess->lock);
+		clear_bit(i, sess->sess_mask);
+		spin_unlock(&sess->lock);
+	}
+	mutex_unlock(&session_list_mutex);
+
+	if (!sess)
+		return -EINVAL;
+
+	/* Close the session */
+	handle_close_session(ta_handle, session_info);
+	handle_unload_ta(ta_handle);
+
+	kref_put_mutex(&sess->refcount, destroy_session, &session_list_mutex);
+
+	return 0;
+}
+
+int amdtee_map_shmem(struct tee_shm *shm)
+{
+	struct amdtee_context_data *ctxdata;
+	struct amdtee_shm_data *shmnode;
+	struct shmem_desc shmem;
+	int rc, count;
+	u32 buf_id;
+
+	if (!shm)
+		return -EINVAL;
+
+	shmnode = kmalloc(sizeof(*shmnode), GFP_KERNEL);
+	if (!shmnode)
+		return -ENOMEM;
+
+	count = 1;
+	shmem.kaddr = shm->kaddr;
+	shmem.size = shm->size;
+
+	/*
+	 * Send a MAP command to TEE and get the corresponding
+	 * buffer Id
+	 */
+	rc = handle_map_shmem(count, &shmem, &buf_id);
+	if (rc) {
+		pr_err("map_shmem failed: ret = %d\n", rc);
+		kfree(shmnode);
+		return rc;
+	}
+
+	shmnode->kaddr = shm->kaddr;
+	shmnode->buf_id = buf_id;
+	ctxdata = shm->ctx->data;
+	mutex_lock(&ctxdata->shm_mutex);
+	list_add(&shmnode->shm_node, &ctxdata->shm_list);
+	mutex_unlock(&ctxdata->shm_mutex);
+
+	pr_debug("buf_id :[%x] kaddr[%p]\n", shmnode->buf_id, shmnode->kaddr);
+
+	return 0;
+}
+
+void amdtee_unmap_shmem(struct tee_shm *shm)
+{
+	struct amdtee_context_data *ctxdata;
+	struct amdtee_shm_data *shmnode;
+	u32 buf_id;
+
+	if (!shm)
+		return;
+
+	buf_id = get_buffer_id(shm);
+	/* Unmap the shared memory from TEE */
+	handle_unmap_shmem(buf_id);
+
+	ctxdata = shm->ctx->data;
+	mutex_lock(&ctxdata->shm_mutex);
+	list_for_each_entry(shmnode, &ctxdata->shm_list, shm_node)
+		if (buf_id == shmnode->buf_id) {
+			list_del(&shmnode->shm_node);
+			kfree(shmnode);
+			break;
+		}
+	mutex_unlock(&ctxdata->shm_mutex);
+}
+
+int amdtee_invoke_func(struct tee_context *ctx,
+		       struct tee_ioctl_invoke_arg *arg,
+		       struct tee_param *param)
+{
+	struct amdtee_context_data *ctxdata = ctx->data;
+	struct amdtee_session *sess;
+	u32 i, session_info;
+
+	/* Check that the session is valid */
+	mutex_lock(&session_list_mutex);
+	sess = find_session(ctxdata, arg->session);
+	if (sess) {
+		i = get_session_index(arg->session);
+		session_info = sess->session_info[i];
+	}
+	mutex_unlock(&session_list_mutex);
+
+	if (!sess)
+		return -EINVAL;
+
+	handle_invoke_cmd(arg, session_info, param);
+
+	return 0;
+}
+
+int amdtee_cancel_req(struct tee_context *ctx, u32 cancel_id, u32 session)
+{
+	return -EINVAL;
+}
+
+static const struct tee_driver_ops amdtee_ops = {
+	.get_version = amdtee_get_version,
+	.open = amdtee_open,
+	.release = amdtee_release,
+	.open_session = amdtee_open_session,
+	.close_session = amdtee_close_session,
+	.invoke_func = amdtee_invoke_func,
+	.cancel_req = amdtee_cancel_req,
+};
+
+static const struct tee_desc amdtee_desc = {
+	.name = DRIVER_NAME "-clnt",
+	.ops = &amdtee_ops,
+	.owner = THIS_MODULE,
+};
+
+static int __init amdtee_driver_init(void)
+{
+	struct tee_device *teedev;
+	struct tee_shm_pool *pool;
+	struct amdtee *amdtee;
+	int rc;
+
+	rc = psp_check_tee_status();
+	if (rc) {
+		pr_err("amd-tee driver: tee not present\n");
+		return rc;
+	}
+
+	drv_data = kzalloc(sizeof(*drv_data), GFP_KERNEL);
+	if (!drv_data)
+		return -ENOMEM;
+
+	amdtee = kzalloc(sizeof(*amdtee), GFP_KERNEL);
+	if (!amdtee) {
+		rc = -ENOMEM;
+		goto err_kfree_drv_data;
+	}
+
+	pool = amdtee_config_shm();
+	if (IS_ERR(pool)) {
+		pr_err("shared pool configuration error\n");
+		rc = PTR_ERR(pool);
+		goto err_kfree_amdtee;
+	}
+
+	teedev = tee_device_alloc(&amdtee_desc, NULL, pool, amdtee);
+	if (IS_ERR(teedev)) {
+		rc = PTR_ERR(teedev);
+		goto err_free_pool;
+	}
+	amdtee->teedev = teedev;
+
+	rc = tee_device_register(amdtee->teedev);
+	if (rc)
+		goto err_device_unregister;
+
+	amdtee->pool = pool;
+
+	drv_data->amdtee = amdtee;
+
+	pr_info("amd-tee driver initialization successful\n");
+	return 0;
+
+err_device_unregister:
+	tee_device_unregister(amdtee->teedev);
+
+err_free_pool:
+	tee_shm_pool_free(pool);
+
+err_kfree_amdtee:
+	kfree(amdtee);
+
+err_kfree_drv_data:
+	kfree(drv_data);
+	drv_data = NULL;
+
+	pr_err("amd-tee driver initialization failed\n");
+	return rc;
+}
+module_init(amdtee_driver_init);
+
+static void __exit amdtee_driver_exit(void)
+{
+	struct amdtee *amdtee;
+
+	if (!drv_data || !drv_data->amdtee)
+		return;
+
+	amdtee = drv_data->amdtee;
+
+	tee_device_unregister(amdtee->teedev);
+	tee_shm_pool_free(amdtee->pool);
+}
+module_exit(amdtee_driver_exit);
+
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION("AMD-TEE driver");
+MODULE_VERSION("1.0");
+MODULE_LICENSE("Dual MIT/GPL");