| Message ID | 1432901799-18359-6-git-send-email-lorenzo.pieralisi@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 29 May 2015 at 08:16, Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> wrote: > 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> > Cc: Mark Rutland <mark.rutland@arm.com> > --- > drivers/firmware/psci.c | 34 ++++++++++++++++++++++++++++++++-- > include/uapi/linux/psci.h | 12 ++++++++++++ > 2 files changed, 44 insertions(+), 2 deletions(-) > > diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c > index 2330099..4063784 100644 > --- a/drivers/firmware/psci.c > +++ b/drivers/firmware/psci.c > @@ -74,14 +74,34 @@ static u32 psci_function_id[PSCI_FN_MAX]; > PSCI_0_2_POWER_STATE_TYPE_MASK | \ > PSCI_0_2_POWER_STATE_AFFL_MASK) > > +#define PSCI_EXT_POWER_STATE_MASK \ > + (PSCI_EXT_POWER_STATE_ID_MASK | \ > + PSCI_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_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_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_EXT_POWER_STATE_MASK : > + PSCI_0_2_POWER_STATE_MASK; > + > + return !(state & ~valid_mask); > } > > static int psci_to_linux_errno(int errno) > @@ -202,6 +222,14 @@ 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). > @@ -280,6 +308,8 @@ static int __init psci_probe(void) > > psci_init_migrate(); > > + psci_init_cpu_suspend(); > + > return 0; > } > > diff --git a/include/uapi/linux/psci.h b/include/uapi/linux/psci.h > index 187b828d..2598d7c 100644 > --- a/include/uapi/linux/psci.h > +++ b/include/uapi/linux/psci.h > @@ -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_EXT_POWER_STATE_ID_MASK 0xfffffff > +#define PSCI_EXT_POWER_STATE_ID_SHIFT 0 > +#define PSCI_EXT_POWER_STATE_TYPE_SHIFT 30 > +#define PSCI_EXT_POWER_STATE_TYPE_MASK \ > + (0x1 << PSCI_EXT_POWER_STATE_TYPE_SHIFT) > + For consistency, dont you need version numbers here, like we have for v0.2? > /* 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_FEATURES_CPU_SUSPEND_PF_SHIFT 1 > +#define PSCI_FEATURES_CPU_SUSPEND_PF_MASK \ > + (0x1 << PSCI_FEATURES_CPU_SUSPEND_PF_SHIFT) > + Likewise. > /* PSCI return values (inclusive of all PSCI versions) */ > #define PSCI_RET_SUCCESS 0 > #define PSCI_RET_NOT_SUPPORTED -1 > -- > 2.2.1 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
On Fri, Jun 05, 2015 at 03:16:36PM +0100, Ashwin Chaugule wrote: > On 29 May 2015 at 08:16, Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> wrote: [...] > > diff --git a/include/uapi/linux/psci.h b/include/uapi/linux/psci.h > > index 187b828d..2598d7c 100644 > > --- a/include/uapi/linux/psci.h > > +++ b/include/uapi/linux/psci.h > > @@ -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_EXT_POWER_STATE_ID_MASK 0xfffffff > > +#define PSCI_EXT_POWER_STATE_ID_SHIFT 0 > > +#define PSCI_EXT_POWER_STATE_TYPE_SHIFT 30 > > +#define PSCI_EXT_POWER_STATE_TYPE_MASK \ > > + (0x1 << PSCI_EXT_POWER_STATE_TYPE_SHIFT) > > + > > For consistency, dont you need version numbers here, like we have for v0.2? According to the docs (page 49, 5.12.2 Implementation responsibilities) the choice is between "Original Format(PSCI0.2)" and "extended stateid" parameter. Do we really need to add a version number to the extended stateid defines ? I could add it, I am not not fussed about this. > > /* 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_FEATURES_CPU_SUSPEND_PF_SHIFT 1 > > +#define PSCI_FEATURES_CPU_SUSPEND_PF_MASK \ > > + (0x1 << PSCI_FEATURES_CPU_SUSPEND_PF_SHIFT) > > + > > Likewise. I could do, yes. Thanks, Lorenzo
diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c index 2330099..4063784 100644 --- a/drivers/firmware/psci.c +++ b/drivers/firmware/psci.c @@ -74,14 +74,34 @@ static u32 psci_function_id[PSCI_FN_MAX]; PSCI_0_2_POWER_STATE_TYPE_MASK | \ PSCI_0_2_POWER_STATE_AFFL_MASK) +#define PSCI_EXT_POWER_STATE_MASK \ + (PSCI_EXT_POWER_STATE_ID_MASK | \ + PSCI_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_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_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_EXT_POWER_STATE_MASK : + PSCI_0_2_POWER_STATE_MASK; + + return !(state & ~valid_mask); } static int psci_to_linux_errno(int errno) @@ -202,6 +222,14 @@ 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). @@ -280,6 +308,8 @@ static int __init psci_probe(void) psci_init_migrate(); + psci_init_cpu_suspend(); + return 0; } diff --git a/include/uapi/linux/psci.h b/include/uapi/linux/psci.h index 187b828d..2598d7c 100644 --- a/include/uapi/linux/psci.h +++ b/include/uapi/linux/psci.h @@ -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_EXT_POWER_STATE_ID_MASK 0xfffffff +#define PSCI_EXT_POWER_STATE_ID_SHIFT 0 +#define PSCI_EXT_POWER_STATE_TYPE_SHIFT 30 +#define PSCI_EXT_POWER_STATE_TYPE_MASK \ + (0x1 << PSCI_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_FEATURES_CPU_SUSPEND_PF_SHIFT 1 +#define PSCI_FEATURES_CPU_SUSPEND_PF_MASK \ + (0x1 << PSCI_FEATURES_CPU_SUSPEND_PF_SHIFT) + /* PSCI return values (inclusive of all PSCI versions) */ #define PSCI_RET_SUCCESS 0 #define PSCI_RET_NOT_SUPPORTED -1
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> Cc: Mark Rutland <mark.rutland@arm.com> --- drivers/firmware/psci.c | 34 ++++++++++++++++++++++++++++++++-- include/uapi/linux/psci.h | 12 ++++++++++++ 2 files changed, 44 insertions(+), 2 deletions(-)