platform/x86/amd/pmf: Add PMF TEE interface

AMD PMF driver loads the PMF TA (Trusted Application) into the AMD
ASP's (AMD Security Processor) TEE (Trusted Execution Environment).

PMF Trusted Application is a secured firmware placed under
/lib/firmware/amdtee gets loaded only when the TEE environment is
initialized. Add the initial code path to build these pipes.

Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
Link: https://lore.kernel.org/r/20231212014705.2017474-2-Shyam-sundar.S-k@amd.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

1 files changed, 105 insertions, 0 deletions

diff --git a/drivers/platform/x86/amd/pmf/tee-if.c b/drivers/platform/x86/amd/pmf/tee-if.c
new file mode 100644
index 000000000000..6ec8c3726624
--- /dev/null
+++ b/drivers/platform/x86/amd/pmf/tee-if.c
@@ -0,0 +1,105 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * AMD Platform Management Framework Driver - TEE Interface
+ *
+ * Copyright (c) 2023, Advanced Micro Devices, Inc.
+ * All Rights Reserved.
+ *
+ * Author: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
+ */
+
+#include <linux/tee_drv.h>
+#include <linux/uuid.h>
+#include "pmf.h"
+
+#define MAX_TEE_PARAM	4
+static const uuid_t amd_pmf_ta_uuid = UUID_INIT(0x6fd93b77, 0x3fb8, 0x524d,
+						0xb1, 0x2d, 0xc5, 0x29, 0xb1, 0x3d, 0x85, 0x43);
+
+static int amd_pmf_amdtee_ta_match(struct tee_ioctl_version_data *ver, const void *data)
+{
+	return ver->impl_id == TEE_IMPL_ID_AMDTEE;
+}
+
+static int amd_pmf_ta_open_session(struct tee_context *ctx, u32 *id)
+{
+	struct tee_ioctl_open_session_arg sess_arg = {};
+	int rc;
+
+	export_uuid(sess_arg.uuid, &amd_pmf_ta_uuid);
+	sess_arg.clnt_login = TEE_IOCTL_LOGIN_PUBLIC;
+	sess_arg.num_params = 0;
+
+	rc = tee_client_open_session(ctx, &sess_arg, NULL);
+	if (rc < 0 || sess_arg.ret != 0) {
+		pr_err("Failed to open TEE session err:%#x, rc:%d\n", sess_arg.ret, rc);
+		return rc;
+	}
+
+	*id = sess_arg.session;
+
+	return rc;
+}
+
+static int amd_pmf_tee_init(struct amd_pmf_dev *dev)
+{
+	u32 size;
+	int ret;
+
+	dev->tee_ctx = tee_client_open_context(NULL, amd_pmf_amdtee_ta_match, NULL, NULL);
+	if (IS_ERR(dev->tee_ctx)) {
+		dev_err(dev->dev, "Failed to open TEE context\n");
+		return PTR_ERR(dev->tee_ctx);
+	}
+
+	ret = amd_pmf_ta_open_session(dev->tee_ctx, &dev->session_id);
+	if (ret) {
+		dev_err(dev->dev, "Failed to open TA session (%d)\n", ret);
+		ret = -EINVAL;
+		goto out_ctx;
+	}
+
+	size = sizeof(struct ta_pmf_shared_memory);
+	dev->fw_shm_pool = tee_shm_alloc_kernel_buf(dev->tee_ctx, size);
+	if (IS_ERR(dev->fw_shm_pool)) {
+		dev_err(dev->dev, "Failed to alloc TEE shared memory\n");
+		ret = PTR_ERR(dev->fw_shm_pool);
+		goto out_sess;
+	}
+
+	dev->shbuf = tee_shm_get_va(dev->fw_shm_pool, 0);
+	if (IS_ERR(dev->shbuf)) {
+		dev_err(dev->dev, "Failed to get TEE virtual address\n");
+		ret = PTR_ERR(dev->shbuf);
+		goto out_shm;
+	}
+	dev_dbg(dev->dev, "TEE init done\n");
+
+	return 0;
+
+out_shm:
+	tee_shm_free(dev->fw_shm_pool);
+out_sess:
+	tee_client_close_session(dev->tee_ctx, dev->session_id);
+out_ctx:
+	tee_client_close_context(dev->tee_ctx);
+
+	return ret;
+}
+
+static void amd_pmf_tee_deinit(struct amd_pmf_dev *dev)
+{
+	tee_shm_free(dev->fw_shm_pool);
+	tee_client_close_session(dev->tee_ctx, dev->session_id);
+	tee_client_close_context(dev->tee_ctx);
+}
+
+int amd_pmf_init_smart_pc(struct amd_pmf_dev *dev)
+{
+	return amd_pmf_tee_init(dev);
+}
+
+void amd_pmf_deinit_smart_pc(struct amd_pmf_dev *dev)
+{
+	amd_pmf_tee_deinit(dev);
+}