imx: add imx8qm/imx8qx SRTC SIP runtime service support

On i.MX8QM/i.MX8QX with system controller inside, the SRTC is
managed by SCFW(system controller firmware) and some functions
like setting SRTC's time etc. can ONLY be requested from secure
world, so SIP runtime service is needed for such kind of operations,
this patch adds SRTC SIP runtime service support for i.MX8QM and
i.MX8QX.
Signed-off-by: Anson Huang <Anson.Huang@nxp.com>

plat/imx/common/imx_sip_handler.c

+/*
+ * Copyright 2019 NXP
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stdlib.h>
+#include <stdint.h>
+#include <std_svc.h>
+#include <platform_def.h>
+#include <common/debug.h>
+#include <common/runtime_svc.h>
+#include <imx_sip_svc.h>
+#include <sci/sci.h>
+
+static int imx_srtc_set_time(uint32_t year_mon,
+			unsigned long day_hour,
+			unsigned long min_sec)
+{
+	return sc_timer_set_rtc_time(ipc_handle,
+		year_mon >> 16, year_mon & 0xffff,
+		day_hour >> 16, day_hour & 0xffff,
+		min_sec >> 16, min_sec & 0xffff);
+}
+
+int imx_srtc_handler(uint32_t smc_fid,
+		    void *handle,
+		    u_register_t x1,
+		    u_register_t x2,
+		    u_register_t x3,
+		    u_register_t x4)
+{
+	int ret;
+
+	switch (x1) {
+	case IMX_SIP_SRTC_SET_TIME:
+		ret = imx_srtc_set_time(x2, x3, x4);
+		break;
+	default:
+		ret = SMC_UNK;
+	}
+
+	SMC_RET1(handle, ret);
+}

plat/imx/common/imx_sip_svc.c

+/*
+ * Copyright (c) 2015-2019, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stdint.h>
+#include <common/debug.h>
+#include <common/runtime_svc.h>
+#include <lib/pmf/pmf.h>
+#include <tools_share/uuid.h>
+#include <imx_sip_svc.h>
+
+static int32_t imx_sip_setup(void)
+{
+	return 0;
+}
+
+static uintptr_t imx_sip_handler(unsigned int smc_fid,
+			u_register_t x1,
+			u_register_t x2,
+			u_register_t x3,
+			u_register_t x4,
+			void *cookie,
+			void *handle,
+			u_register_t flags)
+{
+	switch (smc_fid) {
+#if (defined(PLAT_IMX8QM) || defined(PLAT_IMX8QX))
+	case  IMX_SIP_SRTC:
+		return imx_srtc_handler(smc_fid, handle, x1, x2, x3, x4);
+#endif
+	default:
+		WARN("Unimplemented i.MX SiP Service Call: 0x%x\n", smc_fid);
+		SMC_RET1(handle, SMC_UNK);
+		break;
+	}
+}
+
+/* Define a runtime service descriptor for fast SMC calls */
+DECLARE_RT_SVC(
+		imx_sip_svc,
+		OEN_SIP_START,
+		OEN_SIP_END,
+		SMC_TYPE_FAST,
+		imx_sip_setup,
+		imx_sip_handler
+);

plat/imx/common/include/imx_sip_svc.h

+/*
+ * Copyright (c) 2015-2019, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef __IMX_SIP_SVC_H__
+#define __IMX_SIP_SVC_H__
+
+/* SMC function IDs for SiP Service queries */
+#define IMX_SIP_SRTC			0xC2000002
+#define IMX_SIP_SRTC_SET_TIME		0x00
+
+#if (defined(PLAT_IMX8QM) || defined(PLAT_IMX8QX))
+int imx_srtc_handler(uint32_t smc_fid, void *handle, u_register_t x1,
+		     u_register_t x2, u_register_t x3, u_register_t x4);
+#endif
+
+#endif /* __IMX_SIP_SVC_H__ */

plat/imx/imx8qm/platform.mk

@@ -22,6 +22,8 @@ BL31_SOURCES		+=	plat/imx/common/lpuart_console.S	\
 				plat/imx/imx8qm/imx8qm_psci.c		\
 				plat/imx/common/imx8_topology.c		\
 				plat/imx/common/imx8_psci.c		\
+				plat/imx/common/imx_sip_svc.c		\
+				plat/imx/common/imx_sip_handler.c	\
 				lib/xlat_tables/aarch64/xlat_tables.c		\
 				lib/xlat_tables/xlat_tables_common.c		\
 				lib/cpus/aarch64/cortex_a53.S			\

plat/imx/imx8qx/platform.mk

@@ -21,6 +21,8 @@ BL31_SOURCES		+=	plat/imx/common/lpuart_console.S	\
 				plat/imx/imx8qx/imx8qx_psci.c		\
 				plat/imx/common/imx8_topology.c		\
 				plat/imx/common/imx8_psci.c		\
+				plat/imx/common/imx_sip_svc.c		\
+				plat/imx/common/imx_sip_handler.c	\
 				plat/common/plat_psci_common.c		\
 				lib/xlat_tables/xlat_tables_common.c	\
 				lib/xlat_tables/aarch64/xlat_tables.c	\