Tegra186: implement support for System Suspend

This patch adds the chip level support for System Suspend entry
and exit. As part of the entry sequence we first query the MCE
firmware to check if it is safe to enter system suspend. Once
we get a green light, we save hardware block settings and enter
the power state. As expected, all the hardware settings are
restored once we exit the power state.

Change-Id: I6d192d7568d6a555eb10efdfd45f6d79c20f74ea
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>

5 files changed, 98 insertions, 6 deletions

diff --git a/plat/nvidia/tegra/include/t186/tegra_def.h b/plat/nvidia/tegra/include/t186/tegra_def.h
index 0732993d..f3fbb891 100644
--- a/plat/nvidia/tegra/include/t186/tegra_def.h
+++ b/plat/nvidia/tegra/include/t186/tegra_def.h
@@ -81,6 +81,7 @@
 #define  HARDWARE_MINOR_REVISION_MASK	0xf0000
 #define  HARDWARE_MINOR_REVISION_SHIFT	0x10
 #define  HARDWARE_REVISION_A01		1
+#define  MISCREG_PFCFG			0x200C
 
 /*******************************************************************************
  * Tegra Memory Controller constants
@@ -106,6 +107,16 @@
 #define TEGRA_GICC_BASE			0x03882000
 
 /*******************************************************************************
+ * Security Engine related constants
+ ******************************************************************************/
+#define TEGRA_SE0_BASE			0x03AC0000
+#define  SE_MUTEX_WATCHDOG_NS_LIMIT	0x6C
+#define TEGRA_PKA1_BASE			0x03AD0000
+#define  PKA_MUTEX_WATCHDOG_NS_LIMIT	0x8144
+#define TEGRA_RNG1_BASE			0x03AE0000
+#define  RNG_MUTEX_WATCHDOG_NS_LIMIT	0xFE0
+
+/*******************************************************************************
  * Tegra Clock and Reset Controller constants
  ******************************************************************************/
 #define TEGRA_CAR_RESET_BASE		0x05000000
@@ -124,6 +135,9 @@
  * Tegra scratch registers constants
  ******************************************************************************/
 #define TEGRA_SCRATCH_BASE		0x0C390000
+#define  SECURE_SCRATCH_RSV6		0x680
+#define  SECURE_SCRATCH_RSV11_LO	0x6A8
+#define  SECURE_SCRATCH_RSV11_HI	0x6AC
 
 /*******************************************************************************
  * Tegra Memory Mapped Control Register Access Bus constants
diff --git a/plat/nvidia/tegra/soc/t186/drivers/mce/mce.c b/plat/nvidia/tegra/soc/t186/drivers/mce/mce.c
index 98151070..745b6f4e 100644
--- a/plat/nvidia/tegra/soc/t186/drivers/mce/mce.c
+++ b/plat/nvidia/tegra/soc/t186/drivers/mce/mce.c
@@ -262,7 +262,6 @@ int mce_command_handler(mce_cmd_t cmd, uint64_t arg0, uint64_t arg1,
 		/* update context to return SC7 status value */
 		write_ctx_reg(gp_regs, CTX_GPREG_X1, ret);
 		write_ctx_reg(gp_regs, CTX_GPREG_X3, ret);
-		ret = 0;
 
 		break;
 
diff --git a/plat/nvidia/tegra/soc/t186/plat_psci_handlers.c b/plat/nvidia/tegra/soc/t186/plat_psci_handlers.c
index 20c0f4c1..7e35cc6b 100644
--- a/plat/nvidia/tegra/soc/t186/plat_psci_handlers.c
+++ b/plat/nvidia/tegra/soc/t186/plat_psci_handlers.c
@@ -38,6 +38,7 @@
 #include <denver.h>
 #include <mce.h>
 #include <psci.h>
+#include <smmu.h>
 #include <t18x_ari.h>
 #include <tegra_private.h>
 
@@ -48,7 +49,10 @@ extern void prepare_cpu_pwr_dwn(void);
 /* constants to get power state's wake time */
 #define TEGRA186_WAKE_TIME_MASK		0xFFFFFF
 #define TEGRA186_WAKE_TIME_SHIFT	4
+/* context size to save during system suspend */
+#define TEGRA186_SE_CONTEXT_SIZE		3
 
+static uint32_t se_regs[TEGRA186_SE_CONTEXT_SIZE];
 static unsigned int wake_time[PLATFORM_CORE_COUNT];
 
 /* System power down state */
@@ -89,9 +93,15 @@ int32_t tegra_soc_validate_power_state(unsigned int power_state,
 int tegra_soc_pwr_domain_suspend(const psci_power_state_t *target_state)
 {
 	const plat_local_state_t *pwr_domain_state;
-	unsigned int stateid_afflvl0;
+	unsigned int stateid_afflvl0, stateid_afflvl2;
 	int cpu = read_mpidr() & MPIDR_CPU_MASK;
 	int impl = (read_midr() >> MIDR_IMPL_SHIFT) & MIDR_IMPL_MASK;
+	cpu_context_t *ctx = cm_get_context(NON_SECURE);
+	gp_regs_t *gp_regs = get_gpregs_ctx(ctx);
+	uint32_t val;
+
+	assert(ctx);
+	assert(gp_regs);
 
 	if (impl == DENVER_IMPL)
 		cpu |= 0x4;
@@ -100,6 +110,8 @@ int tegra_soc_pwr_domain_suspend(const psci_power_state_t *target_state)
 	pwr_domain_state = target_state->pwr_domain_state;
 	stateid_afflvl0 = pwr_domain_state[MPIDR_AFFLVL0] &
 		TEGRA186_STATE_ID_MASK;
+	stateid_afflvl2 = pwr_domain_state[PLAT_MAX_PWR_LVL] &
+		TEGRA186_STATE_ID_MASK;
 
 	if (stateid_afflvl0 == PSTATE_ID_CORE_IDLE) {
 
@@ -113,6 +125,42 @@ int tegra_soc_pwr_domain_suspend(const psci_power_state_t *target_state)
 		(void)mce_command_handler(MCE_CMD_ENTER_CSTATE,
 			TEGRA_ARI_CORE_C7, wake_time[cpu], 0);
 
+	} else if (stateid_afflvl2 == PSTATE_ID_SOC_POWERDN) {
+
+		/* loop until SC7 is allowed */
+		do {
+			val = mce_command_handler(MCE_CMD_IS_SC7_ALLOWED,
+					TEGRA_ARI_CORE_C7,
+					MCE_CORE_SLEEP_TIME_INFINITE,
+					0);
+		} while (val == 0);
+
+		/* save SE registers */
+		se_regs[0] = mmio_read_32(TEGRA_SE0_BASE +
+				SE_MUTEX_WATCHDOG_NS_LIMIT);
+		se_regs[1] = mmio_read_32(TEGRA_RNG1_BASE +
+				RNG_MUTEX_WATCHDOG_NS_LIMIT);
+		se_regs[2] = mmio_read_32(TEGRA_PKA1_BASE +
+				PKA_MUTEX_WATCHDOG_NS_LIMIT);
+
+		/* save 'Secure Boot' Processor Feature Config Register */
+		val = mmio_read_32(TEGRA_MISC_BASE + MISCREG_PFCFG);
+		mmio_write_32(TEGRA_SCRATCH_BASE + SECURE_SCRATCH_RSV6, val);
+
+		/* save SMMU context */
+		tegra_smmu_save_context();
+
+		/* Prepare for system suspend */
+		write_ctx_reg(gp_regs, CTX_GPREG_X4, 1);
+		write_ctx_reg(gp_regs, CTX_GPREG_X5, 0);
+		write_ctx_reg(gp_regs, CTX_GPREG_X6, 1);
+		(void)mce_command_handler(MCE_CMD_UPDATE_CSTATE_INFO,
+			TEGRA_ARI_CLUSTER_CC7, 0, TEGRA_ARI_SYSTEM_SC7);
+
+		/* Enter system suspend state */
+		(void)mce_command_handler(MCE_CMD_ENTER_CSTATE,
+			TEGRA_ARI_CORE_C7, MCE_CORE_SLEEP_TIME_INFINITE, 0);
+
 	} else {
 		ERROR("%s: Unknown state id\n", __func__);
 		return PSCI_E_NOT_SUPPORTED;
@@ -140,6 +188,29 @@ int tegra_soc_pwr_domain_on(u_register_t mpidr)
 	return PSCI_E_SUCCESS;
 }
 
+int tegra_soc_pwr_domain_on_finish(const psci_power_state_t *target_state)
+{
+	int state_id = target_state->pwr_domain_state[PLAT_MAX_PWR_LVL];
+
+	/*
+	 * Check if we are exiting from deep sleep and restore SE
+	 * context if we are.
+	 */
+	if (state_id == PSTATE_ID_SOC_POWERDN) {
+		mmio_write_32(TEGRA_SE0_BASE + SE_MUTEX_WATCHDOG_NS_LIMIT,
+			se_regs[0]);
+		mmio_write_32(TEGRA_RNG1_BASE + RNG_MUTEX_WATCHDOG_NS_LIMIT,
+			se_regs[1]);
+		mmio_write_32(TEGRA_PKA1_BASE + PKA_MUTEX_WATCHDOG_NS_LIMIT,
+			se_regs[2]);
+
+		/* Init SMMU */
+		tegra_smmu_init();
+	}
+
+	return PSCI_E_SUCCESS;
+}
+
 int tegra_soc_pwr_domain_off(const psci_power_state_t *target_state)
 {
 	cpu_context_t *ctx = cm_get_context(NON_SECURE);
diff --git a/plat/nvidia/tegra/soc/t186/plat_setup.c b/plat/nvidia/tegra/soc/t186/plat_setup.c
index 44faefef..d6b8bc3f 100644
--- a/plat/nvidia/tegra/soc/t186/plat_setup.c
+++ b/plat/nvidia/tegra/soc/t186/plat_setup.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2016, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -73,13 +73,21 @@ static const mmap_region_t tegra_mmap[] = {
 			MT_DEVICE | MT_RW | MT_SECURE),
 	MAP_REGION_FLAT(TEGRA_GICD_BASE, 0x20000, /* 128KB */
 			MT_DEVICE | MT_RW | MT_SECURE),
+	MAP_REGION_FLAT(TEGRA_SE0_BASE, 0x10000, /* 64KB */
+			MT_DEVICE | MT_RW | MT_SECURE),
+	MAP_REGION_FLAT(TEGRA_PKA1_BASE, 0x10000, /* 64KB */
+			MT_DEVICE | MT_RW | MT_SECURE),
+	MAP_REGION_FLAT(TEGRA_RNG1_BASE, 0x10000, /* 64KB */
+			MT_DEVICE | MT_RW | MT_SECURE),
 	MAP_REGION_FLAT(TEGRA_CAR_RESET_BASE, 0x10000, /* 64KB */
 			MT_DEVICE | MT_RW | MT_SECURE),
 	MAP_REGION_FLAT(TEGRA_PMC_BASE, 0x40000, /* 256KB */
 			MT_DEVICE | MT_RW | MT_SECURE),
+	MAP_REGION_FLAT(TEGRA_SCRATCH_BASE, 0x10000, /* 64KB */
+			MT_DEVICE | MT_RW | MT_SECURE),
 	MAP_REGION_FLAT(TEGRA_MMCRAB_BASE, 0x60000, /* 384KB */
 			MT_DEVICE | MT_RW | MT_SECURE),
-	MAP_REGION_FLAT(TEGRA_SMMU_BASE, 0x10000, /* 64KB */
+	MAP_REGION_FLAT(TEGRA_SMMU_BASE, 0x1000000, /* 64KB */
 			MT_DEVICE | MT_RW | MT_SECURE),
 	{0}
 };
diff --git a/plat/nvidia/tegra/soc/t186/platform_t186.mk b/plat/nvidia/tegra/soc/t186/platform_t186.mk
index 272074c5..adc4a9ee 100644
--- a/plat/nvidia/tegra/soc/t186/platform_t186.mk
+++ b/plat/nvidia/tegra/soc/t186/platform_t186.mk
@@ -42,10 +42,10 @@ $(eval $(call add_define,PLATFORM_CLUSTER_COUNT))
 PLATFORM_MAX_CPUS_PER_CLUSTER		:= 4
 $(eval $(call add_define,PLATFORM_MAX_CPUS_PER_CLUSTER))
 
-MAX_XLAT_TABLES				:= 12
+MAX_XLAT_TABLES				:= 15
 $(eval $(call add_define,MAX_XLAT_TABLES))
 
-MAX_MMAP_REGIONS			:= 12
+MAX_MMAP_REGIONS			:= 15
 $(eval $(call add_define,MAX_MMAP_REGIONS))
 
 # platform files