Tegra186: save system suspend entry marker to TZDRAM
This patch adds support to save the system suspend entry and exit
markers to TZDRAM to help the trampoline code decide if the current
warmboot is actually an exit from System Suspend.
The Tegra186 platform handler sets the system suspend entry marker
before entering SC7 state and the trampoline flips the state back to
system resume, on exiting SC7.
Change-Id: I29d73f1693c89ebc8d19d7abb1df1e460eb5558e
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
diff --git a/plat/nvidia/tegra/include/t186/tegra186_private.h b/plat/nvidia/tegra/include/t186/tegra186_private.h
index 30b1595..9e2c02b 100644
--- a/plat/nvidia/tegra/include/t186/tegra186_private.h
+++ b/plat/nvidia/tegra/include/t186/tegra186_private.h
@@ -11,5 +11,6 @@
uint64_t tegra186_get_cpu_reset_handler_base(void);
uint64_t tegra186_get_cpu_reset_handler_size(void);
uint64_t tegra186_get_smmu_ctx_offset(void);
+void tegra186_set_system_suspend_entry(void);
#endif /* TEGRA186_PRIVATE_H */
diff --git a/plat/nvidia/tegra/soc/t186/plat_psci_handlers.c b/plat/nvidia/tegra/soc/t186/plat_psci_handlers.c
index 162a283..09e257d 100644
--- a/plat/nvidia/tegra/soc/t186/plat_psci_handlers.c
+++ b/plat/nvidia/tegra/soc/t186/plat_psci_handlers.c
@@ -134,6 +134,7 @@
cstate_info.system_state_force = 1;
cstate_info.update_wake_mask = 1;
mce_update_cstate_info(&cstate_info);
+
/* Loop until system suspend is allowed */
do {
val = (uint32_t)mce_command_handler(
@@ -146,6 +147,10 @@
/* Instruct the MCE to enter system suspend state */
(void)mce_command_handler((uint64_t)MCE_CMD_ENTER_CSTATE,
(uint64_t)TEGRA_ARI_CORE_C7, MCE_CORE_SLEEP_TIME_INFINITE, 0U);
+
+ /* set system suspend state for house-keeping */
+ tegra186_set_system_suspend_entry();
+
} else {
; /* do nothing */
}
diff --git a/plat/nvidia/tegra/soc/t186/plat_trampoline.S b/plat/nvidia/tegra/soc/t186/plat_trampoline.S
index d609a14..e3393e9 100644
--- a/plat/nvidia/tegra/soc/t186/plat_trampoline.S
+++ b/plat/nvidia/tegra/soc/t186/plat_trampoline.S
@@ -10,23 +10,32 @@
#include <plat/common/common_def.h>
#include <tegra_def.h>
+#define TEGRA186_STATE_SYSTEM_SUSPEND 0x5C7
+#define TEGRA186_STATE_SYSTEM_RESUME 0x600D
#define TEGRA186_SMMU_CTX_SIZE 0x420
.globl tegra186_cpu_reset_handler
/* CPU reset handler routine */
func tegra186_cpu_reset_handler _align=4
- /*
- * The TZRAM loses state during System Suspend. We use this
- * information to decide if the reset handler is running after a
- * System Suspend. Resume from system suspend requires restoring
- * the entire state from TZDRAM to TZRAM.
- */
- mov x0, #BL31_BASE
- ldr x0, [x0]
- cbnz x0, boot_cpu
+ /* check if we are exiting system suspend state */
+ adr x0, __tegra186_system_suspend_state
+ ldr x1, [x0]
+ mov x2, #TEGRA186_STATE_SYSTEM_SUSPEND
+ lsl x2, x2, #16
+ add x2, x2, #TEGRA186_STATE_SYSTEM_SUSPEND
+ cmp x1, x2
+ bne boot_cpu
+
+ /* set system resume state */
+ mov x1, #TEGRA186_STATE_SYSTEM_RESUME
+ lsl x1, x1, #16
+ mov x2, #TEGRA186_STATE_SYSTEM_RESUME
+ add x1, x1, x2
+ str x1, [x0]
+ dsb sy
- /* resume from system suspend */
+ /* prepare to relocate to TZSRAM */
mov x0, #BL31_BASE
adr x1, __tegra186_cpu_reset_handler_end
adr x2, __tegra186_cpu_reset_handler_data
@@ -70,6 +79,10 @@
.quad tegra_secure_entrypoint
.quad __BL31_END__ - BL31_BASE
+ .globl __tegra186_system_suspend_state
+__tegra186_system_suspend_state:
+ .quad 0
+
.align 4
.globl __tegra186_smmu_context
__tegra186_smmu_context:
@@ -86,6 +99,7 @@
.globl tegra186_get_cpu_reset_handler_size
.globl tegra186_get_cpu_reset_handler_base
.globl tegra186_get_smmu_ctx_offset
+ .globl tegra186_set_system_suspend_entry
/* return size of the CPU reset handler */
func tegra186_get_cpu_reset_handler_size
@@ -108,3 +122,23 @@
sub x0, x0, x1
ret
endfunc tegra186_get_smmu_ctx_offset
+
+/* set system suspend state before SC7 entry */
+func tegra186_set_system_suspend_entry
+ mov x0, #TEGRA_MC_BASE
+ mov x3, #MC_SECURITY_CFG3_0
+ ldr w1, [x0, x3]
+ lsl x1, x1, #32
+ mov x3, #MC_SECURITY_CFG0_0
+ ldr w2, [x0, x3]
+ orr x3, x1, x2 /* TZDRAM base */
+ adr x0, __tegra186_system_suspend_state
+ adr x1, tegra186_cpu_reset_handler
+ sub x2, x0, x1 /* offset in TZDRAM */
+ mov x0, #TEGRA186_STATE_SYSTEM_SUSPEND
+ lsl x0, x0, #16
+ add x0, x0, #TEGRA186_STATE_SYSTEM_SUSPEND
+ str x0, [x3, x2] /* set value in TZDRAM */
+ dsb sy
+ ret
+endfunc tegra186_set_system_suspend_entry