[PATCH v5 10/11] firmware: imx: enclave api to read-common-fuses

[Pankaj Gupta <pankaj.gupta@nxp.com>]

Added an API to read the common fuses only accessible to
enclave-firmware.

Signed-off-by: Pankaj Gupta <pankaj.gupta@nxp.com>
---
 drivers/firmware/imx/ele_base_msg.c       | 80 +++++++++++++++++++++++
 include/linux/firmware/imx/ele_base_msg.h |  7 ++
 2 files changed, 87 insertions(+)

diff --git a/drivers/firmware/imx/ele_base_msg.c b/drivers/firmware/imx/ele_base_msg.c
index b19ab8abeeb8..9785fcdcc29d 100644
--- a/drivers/firmware/imx/ele_base_msg.c
+++ b/drivers/firmware/imx/ele_base_msg.c
@@ -190,3 +190,83 @@ int ele_service_swap(struct device *dev,
 
 	return -EINVAL;
 }
+
+static int read_otp_uniq_id(struct ele_mu_priv *priv, u32 *value)
+{
+	unsigned int tag, command, size, ver, status;
+
+	tag = MSG_TAG(priv->rx_msg.header);
+	command = MSG_COMMAND(priv->rx_msg.header);
+	size = MSG_SIZE(priv->rx_msg.header);
+	ver = MSG_VER(priv->rx_msg.header);
+	status = RES_STATUS(priv->rx_msg.data[0]);
+
+	if (tag == priv->rsp_tag &&
+	    command == ELE_READ_FUSE_REQ &&
+	    size == ELE_READ_FUSE_RSP_MSG_SZ &&
+	    ver == ELE_BASE_API_VERSION &&
+	    status == priv->success_tag) {
+		value[0] = priv->rx_msg.data[1];
+		value[1] = priv->rx_msg.data[2];
+		value[2] = priv->rx_msg.data[3];
+		value[3] = priv->rx_msg.data[4];
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+static int read_fuse_word(struct ele_mu_priv *priv, u32 *value)
+{
+	unsigned int tag, command, size, ver, status;
+
+	tag = MSG_TAG(priv->rx_msg.header);
+	command = MSG_COMMAND(priv->rx_msg.header);
+	size = MSG_SIZE(priv->rx_msg.header);
+	ver = MSG_VER(priv->rx_msg.header);
+	status = RES_STATUS(priv->rx_msg.data[0]);
+
+	if (tag == priv->rsp_tag &&
+	    command == ELE_READ_FUSE_REQ &&
+	    size == ELE_READ_FUSE_REQ_MSG_SZ &&
+	    ver == ELE_BASE_API_VERSION &&
+	    status == priv->success_tag) {
+		value[0] = priv->rx_msg.data[1];
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+int read_common_fuse(struct device *dev,
+		     uint16_t fuse_id, u32 *value)
+{
+	struct ele_mu_priv *priv = dev_get_drvdata(dev);
+	int err;
+
+	err = plat_fill_cmd_msg_hdr(priv,
+				    (struct mu_hdr *)&priv->tx_msg.header,
+				    ELE_READ_FUSE_REQ, 8);
+	if (err) {
+		pr_err("Error: plat_fill_cmd_msg_hdr failed.\n");
+		return err;
+	}
+
+	priv->tx_msg.data[0] = fuse_id;
+	err = imx_ele_msg_send_rcv(priv);
+	if (err < 0)
+		return err;
+
+	switch (fuse_id) {
+	case OTP_UNIQ_ID:
+		err = read_otp_uniq_id(priv, value);
+		break;
+	default:
+		err = read_fuse_word(priv, value);
+		break;
+	}
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(read_common_fuse);
+
diff --git a/include/linux/firmware/imx/ele_base_msg.h b/include/linux/firmware/imx/ele_base_msg.h
index 6fbea7a8d7c9..99a135c21f56 100644
--- a/include/linux/firmware/imx/ele_base_msg.h
+++ b/include/linux/firmware/imx/ele_base_msg.h
@@ -47,6 +47,13 @@
 #define ELE_IMEM_EXPORT			0x1
 #define ELE_IMEM_IMPORT			0x2
 
+#define ELE_READ_FUSE_REQ		0x97
+#define ELE_READ_FUSE_RSP_MSG_SZ	0x07
+#define ELE_READ_FUSE_REQ_MSG_SZ	0x03
+
+#define OTP_UNIQ_ID			0x01
+#define OTFAD_CONFIG			0x2
+
 #define ELE_BASE_API_VERSION		0x6
 
 int ele_get_info(struct device *dev, phys_addr_t addr, u32 data_size);
-- 
2.34.1