ARM: rmobile: Add basic PSCI support for R8A779A0 V3U Falcon

Enable basic PSCI support for R8A779A0 V3U Falcon

Signed-off-by: Hai Pham <hai.pham.ud@renesas.com>
Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
diff --git a/arch/arm/mach-rmobile/Makefile b/arch/arm/mach-rmobile/Makefile
index 81a0ded..195bbeb 100644
--- a/arch/arm/mach-rmobile/Makefile
+++ b/arch/arm/mach-rmobile/Makefile
@@ -15,6 +15,10 @@
 obj-$(CONFIG_RCAR_GEN3) += lowlevel_init_gen3.o cpu_info-rcar.o memmap-gen3.o
 obj-$(CONFIG_RZ_G2) += cpu_info-rzg.o
 
+ifneq ($(CONFIG_R8A779A0),)
+obj-$(CONFIG_ARMV8_PSCI) += psci-r8a779a0.o
+endif
+
 OBJCOPYFLAGS_u-boot-spl.srec := -O srec
 quiet_cmd_objcopy = OBJCOPY $@
 cmd_objcopy = $(OBJCOPY) --gap-fill=0x00 $(OBJCOPYFLAGS) \
diff --git a/arch/arm/mach-rmobile/psci-r8a779a0.c b/arch/arm/mach-rmobile/psci-r8a779a0.c
new file mode 100644
index 0000000..6a85eb2
--- /dev/null
+++ b/arch/arm/mach-rmobile/psci-r8a779a0.c
@@ -0,0 +1,49 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * This file implements basic PSCI support for Renesas r8a779a0 SoC
+ *
+ * Copyright (C) 2020 Renesas Electronics Corp.
+ *
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/psci.h>
+#include <asm/secure.h>
+
+int __secure psci_features(u32 function_id, u32 psci_fid)
+{
+	switch (psci_fid) {
+	case ARM_PSCI_0_2_FN_PSCI_VERSION:
+	case ARM_PSCI_0_2_FN_SYSTEM_RESET:
+		return 0x0;
+	}
+	/* case ARM_PSCI_0_2_FN_CPU_ON: */
+	/* case ARM_PSCI_0_2_FN_CPU_OFF: */
+	/* case ARM_PSCI_0_2_FN_AFFINITY_INFO: */
+	/* case ARM_PSCI_0_2_FN_MIGRATE_INFO_TYPE: */
+	/* case ARM_PSCI_0_2_FN_SYSTEM_OFF: */
+	return ARM_PSCI_RET_NI;
+}
+
+u32 __secure psci_version(void)
+{
+	return ARM_PSCI_VER_0_2;
+}
+
+#define RST_BASE	0xE6160000 /* Domain0 */
+#define RST_SRESCR0	(RST_BASE + 0x18)
+#define RST_SPRES	0x5AA58000
+
+void __secure __noreturn psci_system_reset(void)
+{
+	writel(RST_SPRES, RST_SRESCR0);
+
+	while (1)
+		;
+}
+
+int psci_update_dt(void *fdt)
+{
+	return 0;
+}
diff --git a/configs/r8a779a0_falcon_defconfig b/configs/r8a779a0_falcon_defconfig
index dad8b77..8df647a 100644
--- a/configs/r8a779a0_falcon_defconfig
+++ b/configs/r8a779a0_falcon_defconfig
@@ -10,6 +10,7 @@
 CONFIG_RCAR_GEN3=y
 CONFIG_TARGET_FALCON=y
 # CONFIG_PSCI_RESET is not set
+CONFIG_ARMV8_PSCI=y
 CONFIG_DEFAULT_DEVICE_TREE="r8a779a0-falcon-u-boot"
 CONFIG_FIT=y
 CONFIG_SUPPORT_RAW_INITRD=y