imx: ele_api: add DEK Blob generation

- Add crc computation.
- Add ele_generate_dek_blob API for encrypted boot support.

Signed-off-by: Clement Faure <[email protected]>
Signed-off-by: Peng Fan <[email protected]>

1 files changed, 44 insertions, 0 deletions

diff --git a/drivers/misc/imx_ele/ele_api.c b/drivers/misc/imx_ele/ele_api.c
index 0ca0a94f08c..8a14cf6aa92 100644
--- a/drivers/misc/imx_ele/ele_api.c
+++ b/drivers/misc/imx_ele/ele_api.c
@@ -14,6 +14,18 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
+static u32 compute_crc(const struct ele_msg *msg)
+{
+	u32 crc = 0;
+	size_t i = 0;
+	u32 *data = (u32 *)msg;
+
+	for (i = 0; i < (msg->size - 1); i++)
+		crc ^= data[i];
+
+	return crc;
+}
+
 int ele_release_rdc(u8 core_id, u8 xrdc, u32 *response)
 {
 	struct udevice *dev = gd->arch.ele_dev;
@@ -552,3 +564,35 @@ int ele_return_lifecycle_update(ulong signed_msg_blk, u32 *response)
 
 	return ret;
 }
+
+int ele_generate_dek_blob(u32 key_id, u32 src_paddr, u32 dst_paddr, u32 max_output_size)
+{
+	struct udevice *dev = gd->arch.ele_dev;
+	int size = sizeof(struct ele_msg);
+	struct ele_msg msg;
+	int ret;
+
+	if (!dev) {
+		printf("ele dev is not initialized\n");
+		return -ENODEV;
+	}
+
+	msg.version = ELE_VERSION;
+	msg.tag = ELE_CMD_TAG;
+	msg.size = 8;
+	msg.command = ELE_GENERATE_DEK_BLOB;
+	msg.data[0] = key_id;
+	msg.data[1] = 0x0;
+	msg.data[2] = src_paddr;
+	msg.data[3] = 0x0;
+	msg.data[4] = dst_paddr;
+	msg.data[5] = max_output_size;
+	msg.data[6] = compute_crc(&msg);
+
+	ret = misc_call(dev, false, &msg, size, &msg, size);
+	if (ret)
+		printf("Error: %s: ret 0x%x, response 0x%x\n",
+		       __func__, ret, msg.data[0]);
+
+	return ret;
+}