intel: Fix Coverity Scan Defects

Fix mailbox driver incompatible cast bug and control flow issue that
was flagged by Coverity Scan.

Signed-off-by: Abdul Halim, Muhammad Hadi Asyrafi <muhammad.hadi.asyrafi.abdul.halim@intel.com>
Change-Id: I3f34e98d24e40139d31cf7d5b9b973cd2d981065
diff --git a/plat/intel/soc/common/socfpga_sip_svc.c b/plat/intel/soc/common/socfpga_sip_svc.c
index 5b600e5..1c3d45b 100644
--- a/plat/intel/soc/common/socfpga_sip_svc.c
+++ b/plat/intel/soc/common/socfpga_sip_svc.c
@@ -61,7 +61,7 @@
 
 static int intel_fpga_sdm_write_buffer(struct fpga_config_info *buffer)
 {
-	uint32_t args[3];
+	uint64_t args[3];
 
 	while (max_blocks > 0 && buffer->size > buffer->size_written) {
 		args[0] = (1<<8);
@@ -256,7 +256,7 @@
 {
 	if (size > (UINT64_MAX - addr))
 		return false;
-	if (addr < DRAM_BASE)
+	if (addr < BL31_LIMIT)
 		return false;
 	if (addr + size > DRAM_BASE + DRAM_SIZE)
 		return false;
@@ -387,7 +387,7 @@
 
 static uint32_t intel_rsu_notify(uint64_t execution_stage)
 {
-	if (mailbox_hps_stage_notify((uint32_t)execution_stage) < 0)
+	if (mailbox_hps_stage_notify(execution_stage) < 0)
 		return INTEL_SIP_SMC_STATUS_ERROR;
 
 	return INTEL_SIP_SMC_STATUS_OK;
@@ -404,7 +404,7 @@
 }
 
 /* Mailbox services */
-static uint32_t intel_mbox_send_cmd(uint32_t cmd, uint32_t *args, int len,
+static uint32_t intel_mbox_send_cmd(uint32_t cmd, uint64_t *args, int len,
 				    int urgent, uint32_t *response,
 				    int resp_len, int *mbox_status,
 				    int *len_in_resp)
@@ -542,7 +542,7 @@
 	case INTEL_SIP_SMC_MBOX_SEND_CMD:
 		x5 = SMC_GET_GP(handle, CTX_GPREG_X5);
 		x6 = SMC_GET_GP(handle, CTX_GPREG_X6);
-		status = intel_mbox_send_cmd(x1, (uint32_t *)x2, x3, x4,
+		status = intel_mbox_send_cmd(x1, (uint64_t *)x2, x3, x4,
 					     (uint32_t *)x5, x6, &mbox_status,
 					     &len_in_resp);
 		SMC_RET4(handle, status, mbox_status, x5, len_in_resp);