diff --git a/plat/intel/soc/agilex/bl31_plat_setup.c b/plat/intel/soc/agilex/bl31_plat_setup.c
index 13099b4..4b11440 100644
--- a/plat/intel/soc/agilex/bl31_plat_setup.c
+++ b/plat/intel/soc/agilex/bl31_plat_setup.c
@@ -14,6 +14,7 @@
 #include <lib/mmio.h>
 #include <lib/xlat_tables/xlat_tables.h>
 
+#include "socfpga_mailbox.h"
 #include "socfpga_private.h"
 
 static entry_point_info_t bl32_image_ep_info;
@@ -107,6 +108,8 @@
 	/* Signal secondary CPUs to jump to BL31 (BL2 = U-boot SPL) */
 	mmio_write_64(PLAT_CPU_RELEASE_ADDR,
 		(uint64_t)plat_secondary_cpus_bl31_entry);
+
+	mailbox_hps_stage_notify(HPS_EXECUTION_STATE_SSBL);
 }
 
 const mmap_region_t plat_agilex_mmap[] = {
diff --git a/plat/intel/soc/common/include/socfpga_mailbox.h b/plat/intel/soc/common/include/socfpga_mailbox.h
index c4b9e59..38f4696 100644
--- a/plat/intel/soc/common/include/socfpga_mailbox.h
+++ b/plat/intel/soc/common/include/socfpga_mailbox.h
@@ -73,6 +73,29 @@
 /* Mailbox REBOOT commands */
 #define MBOX_CMD_REBOOT_HPS		71
 
+/* Mailbox RSU commands */
+#define MBOX_GET_SUBPARTITION_TABLE	90
+#define MBOX_RSU_STATUS			91
+#define MBOX_RSU_UPDATE			92
+
+/* Mailbox RSU macros */
+#define RSU_VERSION_ACMF		BIT(8)
+#define RSU_VERSION_ACMF_MASK		0xff00
+
+/* HPS stage notify command */
+#define MBOX_HPS_STAGE_NOTIFY		93
+
+/* Execution states for HPS_STAGE_NOTIFY */
+#define HPS_EXECUTION_STATE_FSBL	0
+#define HPS_EXECUTION_STATE_SSBL	1
+#define HPS_EXECUTION_STATE_OS		2
+
+/* Mailbox reconfiguration commands */
+#define MBOX_CONFIG_STATUS		4
+#define MBOX_RECONFIG			6
+#define MBOX_RECONFIG_DATA		8
+#define MBOX_RECONFIG_STATUS		9
+
 /* Generic error handling */
 #define MBOX_TIMEOUT			-2047
 #define MBOX_NO_RESPONSE		-2
@@ -98,13 +121,6 @@
 #define MBOX_CFGSTAT_STATE_ERROR_BOOT_INFO		0xf0000007
 #define MBOX_CFGSTAT_STATE_ERROR_QSPI_ERROR		0xf0000008
 
-/* Mailbox reconfiguration commands */
-#define MBOX_CONFIG_STATUS	4
-#define MBOX_RECONFIG		6
-#define MBOX_RECONFIG_DATA	8
-#define MBOX_RECONFIG_STATUS	9
-
-
 void mailbox_set_int(int interrupt_input);
 int mailbox_init(void);
 void mailbox_set_qspi_close(void);
@@ -122,4 +138,9 @@
 uint32_t intel_mailbox_get_config_status(uint32_t cmd);
 int intel_mailbox_is_fpga_not_ready(void);
 
+int mailbox_rsu_get_spt_offset(uint32_t *resp_buf, uint32_t resp_buf_len);
+int mailbox_rsu_status(uint32_t *resp_buf, uint32_t resp_buf_len);
+int mailbox_rsu_update(uint32_t *flash_offset);
+int mailbox_hps_stage_notify(uint32_t execution_stage);
+
 #endif /* SOCFPGA_MBOX_H */
diff --git a/plat/intel/soc/common/include/socfpga_sip_svc.h b/plat/intel/soc/common/include/socfpga_sip_svc.h
index 6bb41f3..2b1d983 100644
--- a/plat/intel/soc/common/include/socfpga_sip_svc.h
+++ b/plat/intel/soc/common/include/socfpga_sip_svc.h
@@ -28,6 +28,7 @@
 #define INTEL_SIP_LEGACY_SMC_ECC_DBE			0xC200000D
 #define INTEL_SIP_SMC_RSU_NOTIFY			0xC200000E
 #define INTEL_SIP_SMC_RSU_RETRY_COUNTER			0xC200000F
+#define INTEL_SIP_SMC_MBOX_SEND_CMD			0xC200001E
 
 /* FPGA config helpers */
 #define INTEL_SIP_SMC_FPGA_CONFIG_ADDR			0x400000
diff --git a/plat/intel/soc/common/soc/socfpga_mailbox.c b/plat/intel/soc/common/soc/socfpga_mailbox.c
index 8d7c1d6..673c2d5 100644
--- a/plat/intel/soc/common/soc/socfpga_mailbox.c
+++ b/plat/intel/soc/common/soc/socfpga_mailbox.c
@@ -267,6 +267,55 @@
 	mailbox_send_cmd(MBOX_JOB_ID, MBOX_CMD_REBOOT_HPS, 0, 0, 0, NULL, 0);
 }
 
+int mailbox_rsu_get_spt_offset(uint32_t *resp_buf, uint32_t resp_buf_len)
+{
+	return mailbox_send_cmd(MBOX_JOB_ID, MBOX_GET_SUBPARTITION_TABLE,
+				NULL, 0, 0, (uint32_t *)resp_buf,
+				resp_buf_len);
+}
+
+struct rsu_status_info {
+	uint64_t current_image;
+	uint64_t fail_image;
+	uint32_t state;
+	uint32_t version;
+	uint32_t error_location;
+	uint32_t error_details;
+	uint32_t retry_counter;
+};
+
+int mailbox_rsu_status(uint32_t *resp_buf, uint32_t resp_buf_len)
+{
+	int ret;
+	struct rsu_status_info *info = (struct rsu_status_info *)resp_buf;
+
+	info->retry_counter = ~0;
+
+	ret = mailbox_send_cmd(MBOX_JOB_ID, MBOX_RSU_STATUS, NULL, 0, 0,
+			       (uint32_t *)resp_buf, resp_buf_len);
+
+	if (ret < 0)
+		return ret;
+
+	if (info->retry_counter != ~0)
+		if (!(info->version & RSU_VERSION_ACMF_MASK))
+			info->version |= RSU_VERSION_ACMF;
+
+	return ret;
+}
+
+int mailbox_rsu_update(uint32_t *flash_offset)
+{
+	return mailbox_send_cmd(MBOX_JOB_ID, MBOX_RSU_UPDATE,
+				(uint32_t *)flash_offset, 2, 0, NULL, 0);
+}
+
+int mailbox_hps_stage_notify(uint32_t execution_stage)
+{
+	return mailbox_send_cmd(MBOX_JOB_ID, MBOX_HPS_STAGE_NOTIFY,
+				&execution_stage, 1, 0, NULL, 0);
+}
+
 int mailbox_init(void)
 {
 	int status = 0;
diff --git a/plat/intel/soc/common/socfpga_psci.c b/plat/intel/soc/common/socfpga_psci.c
index d8a6c19..d27ab9f 100644
--- a/plat/intel/soc/common/socfpga_psci.c
+++ b/plat/intel/soc/common/socfpga_psci.c
@@ -130,9 +130,14 @@
 	panic();
 }
 
+extern uint64_t intel_rsu_update_address;
+
 static void __dead2 socfpga_system_reset(void)
 {
-	mailbox_reset_cold();
+	if (intel_rsu_update_address)
+		mailbox_rsu_update((uint32_t *)&intel_rsu_update_address);
+	else
+		mailbox_reset_cold();
 
 	while (1)
 		wfi();
diff --git a/plat/intel/soc/common/socfpga_sip_svc.c b/plat/intel/soc/common/socfpga_sip_svc.c
index 41dae9e..b4fe6d6 100644
--- a/plat/intel/soc/common/socfpga_sip_svc.c
+++ b/plat/intel/soc/common/socfpga_sip_svc.c
@@ -365,6 +365,61 @@
 	return INTEL_SIP_SMC_STATUS_ERROR;
 }
 
+/* Intel Remote System Update (RSU) services */
+uint64_t intel_rsu_update_address;
+
+static uint32_t intel_rsu_status(uint64_t *respbuf, uint32_t respbuf_sz)
+{
+	if (mailbox_rsu_status((uint32_t *)respbuf, respbuf_sz) < 0)
+		return INTEL_SIP_SMC_STATUS_ERROR;
+
+	return INTEL_SIP_SMC_STATUS_OK;
+}
+
+static uint32_t intel_rsu_update(uint64_t update_address)
+{
+	intel_rsu_update_address = update_address;
+	return INTEL_SIP_SMC_STATUS_OK;
+}
+
+static uint32_t intel_rsu_notify(uint64_t execution_stage)
+{
+	if (mailbox_hps_stage_notify((uint32_t)execution_stage) < 0)
+		return INTEL_SIP_SMC_STATUS_ERROR;
+
+	return INTEL_SIP_SMC_STATUS_OK;
+}
+
+static uint32_t intel_rsu_retry_counter(uint32_t *respbuf, uint32_t respbuf_sz,
+					uint32_t *ret_stat)
+{
+	if (mailbox_rsu_status((uint32_t *)respbuf, respbuf_sz) < 0)
+		return INTEL_SIP_SMC_STATUS_ERROR;
+
+	*ret_stat = respbuf[8];
+	return INTEL_SIP_SMC_STATUS_OK;
+}
+
+/* Mailbox services */
+static uint32_t intel_mbox_send_cmd(uint32_t cmd, uint32_t *args, int len,
+				    int urgent, uint32_t *response,
+				    int resp_len, int *mbox_status,
+				    int *len_in_resp)
+{
+	int status = mailbox_send_cmd(MBOX_JOB_ID, cmd, args, len, urgent,
+				      response, resp_len);
+
+	if (status < 0) {
+		*len_in_resp = 0;
+		*mbox_status = -status;
+		return INTEL_SIP_SMC_STATUS_ERROR;
+	}
+
+	*mbox_status = 0;
+	*len_in_resp = status;
+	return INTEL_SIP_SMC_STATUS_OK;
+}
+
 /*
  * This function is responsible for handling all SiP calls from the NS world
  */
@@ -381,7 +436,10 @@
 	uint32_t val = 0;
 	uint32_t status = INTEL_SIP_SMC_STATUS_OK;
 	uint32_t completed_addr[3];
+	uint64_t rsu_respbuf[9];
 	uint32_t count = 0;
+	u_register_t x5, x6;
+	int mbox_status, len_in_resp;
 
 	switch (smc_fid) {
 	case SIP_SVC_UID:
@@ -446,6 +504,41 @@
 						 (uint32_t)x3, &val);
 		SMC_RET3(handle, status, val, x1);
 
+	case INTEL_SIP_SMC_RSU_STATUS:
+		status = intel_rsu_status(rsu_respbuf,
+					ARRAY_SIZE(rsu_respbuf));
+		if (status) {
+			SMC_RET1(handle, status);
+		} else {
+			SMC_RET4(handle, rsu_respbuf[0], rsu_respbuf[1],
+					rsu_respbuf[2], rsu_respbuf[3]);
+		}
+
+	case INTEL_SIP_SMC_RSU_UPDATE:
+		status = intel_rsu_update(x1);
+		SMC_RET1(handle, status);
+
+	case INTEL_SIP_SMC_RSU_NOTIFY:
+		status = intel_rsu_notify(x1);
+		SMC_RET1(handle, status);
+
+	case INTEL_SIP_SMC_RSU_RETRY_COUNTER:
+		status = intel_rsu_retry_counter((uint32_t *)rsu_respbuf,
+						ARRAY_SIZE(rsu_respbuf), &val);
+		if (status) {
+			SMC_RET1(handle, status);
+		} else {
+			SMC_RET2(handle, status, val);
+		}
+
+	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,
+					     (uint32_t *)x5, x6, &mbox_status,
+					     &len_in_resp);
+		SMC_RET4(handle, status, mbox_status, x5, len_in_resp);
+
 	default:
 		return socfpga_sip_handler(smc_fid, x1, x2, x3, x4,
 			cookie, handle, flags);
diff --git a/plat/intel/soc/stratix10/bl31_plat_setup.c b/plat/intel/soc/stratix10/bl31_plat_setup.c
index 29f57c4..4c31238 100644
--- a/plat/intel/soc/stratix10/bl31_plat_setup.c
+++ b/plat/intel/soc/stratix10/bl31_plat_setup.c
@@ -16,6 +16,7 @@
 #include <plat/common/platform.h>
 #include <platform_def.h>
 
+#include "socfpga_mailbox.h"
 #include "socfpga_private.h"
 #include "socfpga_reset_manager.h"
 #include "socfpga_system_manager.h"
@@ -115,6 +116,8 @@
 	/* Signal secondary CPUs to jump to BL31 (BL2 = U-boot SPL) */
 	mmio_write_64(PLAT_CPU_RELEASE_ADDR,
 		(uint64_t)plat_secondary_cpus_bl31_entry);
+
+	mailbox_hps_stage_notify(HPS_EXECUTION_STATE_SSBL);
 }
 
 const mmap_region_t plat_stratix10_mmap[] = {