ti_sci_*: Add utility to access tisci firmware and SOC capability

Introduce response and request structs for receiving information
regarding FW/SOC capability from DM. The received capability can
further be used to call certain API's based on the feature supoorted
by the DM firmware.

Signed-off-by: Moteen Shah <m-shah@ti.com>
Reviewed-by: Neha Malcom Francis <n-francis@ti.com>
Reviewed-by: Dhruva Gole <d-gole@ti.com>
diff --git a/drivers/firmware/ti_sci.h b/drivers/firmware/ti_sci.h
index bb8bc7b..292f7cd 100644
--- a/drivers/firmware/ti_sci.h
+++ b/drivers/firmware/ti_sci.h
@@ -27,6 +27,7 @@
 #define TI_SCI_MSG_BOARD_CONFIG_SECURITY  0x000d
 #define TI_SCI_MSG_BOARD_CONFIG_PM	0x000e
 #define TISCI_MSG_QUERY_MSMC		0x0020
+#define TI_SCI_MSG_QUERY_FW_CAPS	0x0022
 
 /* Device requests */
 #define TI_SCI_MSG_SET_DEVICE_STATE	0x0200
@@ -135,6 +136,18 @@
 } __packed;
 
 /**
+ * struct ti_sci_query_fw_caps_resp - Response for a message
+ * @hdr:	Generic header
+ * @fw_caps:	64-bit value representing the FW/SOC capabilities.
+ *
+ * Response to a message with message type TI_SCI_MSG_QUERY_FW_CAPS
+ */
+struct ti_sci_query_fw_caps_resp {
+	struct ti_sci_msg_hdr hdr;
+	u64    fw_caps;
+} __packed;
+
+/**
  * struct ti_sci_msg_req_reboot - Reboot the SoC
  * @hdr:	Generic Header
  * @domain:	Domain to be reset, 0 for full SoC reboot.