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drivers: firmware: psci: add extended stateid power_state support

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PSCI v1.0 augmented the power_state parameter format specification
(extended stateid) and introduced a way to probe it through the
PSCI_FEATURES interface.

This patch implements code that detects the power_state format at
run-time through the PSCI_FEATURES interface, so that the power_state
argument can be properly detected and validated in the kernel according
to the information provided through firmware.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Jisheng Zhang <jszhang@marvell.com>
Cc: Mark Rutland <mark.rutland@arm.com>
This commit is contained in:
Lorenzo Pieralisi 2015-05-26 17:10:32 +01:00
parent 5f004e0c9f
commit a5c00bb28d
2 changed files with 44 additions and 2 deletions
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34
drivers/firmware/psci.c
View file

@ -75,14 +75,34 @@ static u32 psci_function_id[PSCI_FN_MAX];
PSCI_0_2_POWER_STATE_TYPE_MASK | \
PSCI_0_2_POWER_STATE_AFFL_MASK)
#define PSCI_1_0_EXT_POWER_STATE_MASK \
(PSCI_1_0_EXT_POWER_STATE_ID_MASK | \
PSCI_1_0_EXT_POWER_STATE_TYPE_MASK)
static u32 psci_cpu_suspend_feature;
static inline bool psci_has_ext_power_state(void)
{
return psci_cpu_suspend_feature &
PSCI_1_0_FEATURES_CPU_SUSPEND_PF_MASK;
}
bool psci_power_state_loses_context(u32 state)
{
return state & PSCI_0_2_POWER_STATE_TYPE_MASK;
const u32 mask = psci_has_ext_power_state() ?
PSCI_1_0_EXT_POWER_STATE_TYPE_MASK :
PSCI_0_2_POWER_STATE_TYPE_MASK;
return state & mask;
}
bool psci_power_state_is_valid(u32 state)
{
return !(state & ~PSCI_0_2_POWER_STATE_MASK);
const u32 valid_mask = psci_has_ext_power_state() ?
PSCI_1_0_EXT_POWER_STATE_MASK :
PSCI_0_2_POWER_STATE_MASK;
return !(state & ~valid_mask);
}
static int psci_to_linux_errno(int errno)
@ -203,6 +223,14 @@ static int __init psci_features(u32 psci_func_id)
psci_func_id, 0, 0);
}
static void __init psci_init_cpu_suspend(void)
{
int feature = psci_features(psci_function_id[PSCI_FN_CPU_SUSPEND]);
if (feature != PSCI_RET_NOT_SUPPORTED)
psci_cpu_suspend_feature = feature;
}
/*
* Detect the presence of a resident Trusted OS which may cause CPU_OFF to
* return DENIED (which would be fatal).
@ -287,6 +315,8 @@ static int __init psci_probe(void)
psci_init_migrate();
psci_init_cpu_suspend();
return 0;
}

12
include/uapi/linux/psci.h
View file

@ -58,6 +58,13 @@
#define PSCI_0_2_POWER_STATE_AFFL_MASK \
(0x3 << PSCI_0_2_POWER_STATE_AFFL_SHIFT)
/* PSCI extended power state encoding for CPU_SUSPEND function */
#define PSCI_1_0_EXT_POWER_STATE_ID_MASK 0xfffffff
#define PSCI_1_0_EXT_POWER_STATE_ID_SHIFT 0
#define PSCI_1_0_EXT_POWER_STATE_TYPE_SHIFT 30
#define PSCI_1_0_EXT_POWER_STATE_TYPE_MASK \
(0x1 << PSCI_1_0_EXT_POWER_STATE_TYPE_SHIFT)
/* PSCI v0.2 affinity level state returned by AFFINITY_INFO */
#define PSCI_0_2_AFFINITY_LEVEL_ON 0
#define PSCI_0_2_AFFINITY_LEVEL_OFF 1
@ -78,6 +85,11 @@
#define PSCI_VERSION_MINOR(ver) \
((ver) & PSCI_VERSION_MINOR_MASK)
/* PSCI features decoding (>=1.0) */
#define PSCI_1_0_FEATURES_CPU_SUSPEND_PF_SHIFT 1
#define PSCI_1_0_FEATURES_CPU_SUSPEND_PF_MASK \
(0x1 << PSCI_1_0_FEATURES_CPU_SUSPEND_PF_SHIFT)
/* PSCI return values (inclusive of all PSCI versions) */
#define PSCI_RET_SUCCESS 0
#define PSCI_RET_NOT_SUPPORTED -1