ACPI: Store NVS state even when entering suspend to RAM
https://bugzilla.kernel.org/show_bug.cgi?id=13931 describes a bug where
a system fails to successfully resume after the second suspend. Maxim
Levitsky discovered that this could be rectified by forcibly saving
and restoring the ACPI non-volatile state. The spec indicates that this
is only required for S4, but testing the behaviour of Windows by adding
an ACPI NVS region to qemu's e820 map and registering a custom memory
read/write handler reveals that it's saved and restored even over suspend
to RAM. We should mimic that behaviour to avoid other broken platforms.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c
index bcaa6ef..403daf0 100644
--- a/drivers/acpi/sleep.c
+++ b/drivers/acpi/sleep.c
@@ -112,6 +112,8 @@
{
int error = acpi_sleep_prepare(acpi_target_sleep_state);
+ suspend_nvs_save();
+
if (error)
acpi_target_sleep_state = ACPI_STATE_S0;
return error;
@@ -140,6 +142,8 @@
{
u32 acpi_state = acpi_target_sleep_state;
+ suspend_nvs_free();
+
if (acpi_state == ACPI_STATE_S0)
return;
@@ -189,6 +193,11 @@
u32 acpi_state = acpi_suspend_states[pm_state];
int error = 0;
+ error = suspend_nvs_alloc();
+
+ if (error)
+ return error;
+
if (sleep_states[acpi_state]) {
acpi_target_sleep_state = acpi_state;
acpi_sleep_tts_switch(acpi_target_sleep_state);
@@ -264,6 +273,8 @@
if (acpi_state == ACPI_STATE_S3)
acpi_restore_state_mem();
+ suspend_nvs_restore();
+
return ACPI_SUCCESS(status) ? 0 : -EFAULT;
}
@@ -430,12 +441,6 @@
return ACPI_SUCCESS(status) ? 0 : -EFAULT;
}
-static void acpi_hibernation_finish(void)
-{
- suspend_nvs_free();
- acpi_pm_finish();
-}
-
static void acpi_hibernation_leave(void)
{
/*
@@ -473,7 +478,7 @@
.begin = acpi_hibernation_begin,
.end = acpi_pm_end,
.pre_snapshot = acpi_hibernation_pre_snapshot,
- .finish = acpi_hibernation_finish,
+ .finish = acpi_pm_finish,
.prepare = acpi_pm_prepare,
.enter = acpi_hibernation_enter,
.leave = acpi_hibernation_leave,
@@ -526,7 +531,7 @@
.begin = acpi_hibernation_begin_old,
.end = acpi_pm_end,
.pre_snapshot = acpi_hibernation_pre_snapshot_old,
- .finish = acpi_hibernation_finish,
+ .finish = acpi_pm_finish,
.prepare = acpi_pm_disable_gpes,
.enter = acpi_hibernation_enter,
.leave = acpi_hibernation_leave,