diff options
| author | Dave Martin <dave.martin@linaro.org> | 2013-02-13 16:20:44 +0000 |
|---|---|---|
| committer | Nicolas Pitre <nicolas.pitre@linaro.org> | 2013-06-20 00:45:30 -0400 |
| commit | 8e3aa3f1462fc25b810e867059b292675f0d3a94 (patch) | |
| tree | 474e36c5d066286be965e6b9c3e36d6c6fa739c5 | |
| parent | 21ba6d493d0aa19b1932880ebbab057a99a9a9a1 (diff) | |
ARM: bL_switcher: Add query interface to discover CPU affinities
When the switcher is active, there is no straightforward way to
figure out which logical CPU a given physical CPU maps to.
This patch provides a function
bL_switcher_get_logical_index(mpidr), which is analogous to
get_logical_index().
This function returns the logical CPU on which the specified
physical CPU is grouped (or -EINVAL if unknown).
If the switcher is inactive or not present, -EUNATCH is returned instead.
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
| -rw-r--r-- | arch/arm/common/bL_switcher.c | 20 | ||||
| -rw-r--r-- | arch/arm/include/asm/bL_switcher.h | 2 |
2 files changed, 22 insertions, 0 deletions
diff --git a/arch/arm/common/bL_switcher.c b/arch/arm/common/bL_switcher.c index 38c852627c3..1883c5b3e3f 100644 --- a/arch/arm/common/bL_switcher.c +++ b/arch/arm/common/bL_switcher.c @@ -571,6 +571,26 @@ static int bL_switcher_halve_cpus(void) return 0; } +/* Determine the logical CPU a given physical CPU is grouped on. */ +int bL_switcher_get_logical_index(u32 mpidr) +{ + int cpu; + + if (!bL_switcher_active) + return -EUNATCH; + + mpidr &= MPIDR_HWID_BITMASK; + for_each_online_cpu(cpu) { + int pairing = bL_switcher_cpu_pairing[cpu]; + if (pairing == -1) + continue; + if ((mpidr == cpu_logical_map(cpu)) || + (mpidr == cpu_logical_map(pairing))) + return cpu; + } + return -EINVAL; +} + static void bL_switcher_trace_trigger_cpu(void *__always_unused info) { trace_cpu_migrate_current(get_ns(), read_mpidr()); diff --git a/arch/arm/include/asm/bL_switcher.h b/arch/arm/include/asm/bL_switcher.h index 31df916c40a..482383b45c9 100644 --- a/arch/arm/include/asm/bL_switcher.h +++ b/arch/arm/include/asm/bL_switcher.h @@ -58,6 +58,7 @@ bool bL_switcher_get_enabled(void); void bL_switcher_put_enabled(void); int bL_switcher_trace_trigger(void); +int bL_switcher_get_logical_index(u32 mpidr); #else static void bL_switch_request_detach(unsigned int cpu, @@ -76,6 +77,7 @@ static inline int bL_switcher_unregister_notifier(struct notifier_block *nb) static inline bool bL_switcher_get_enabled(void) { return false; } static inline void bL_switcher_put_enabled(void) { } static inline int bL_switcher_trace_trigger(void) { return 0; } +static inline int bL_switcher_get_logical_index(u32 mpidr) { return -EUNATCH; } #endif /* CONFIG_BL_SWITCHER */ #endif |