Message ID | 1408004865-27525-1-git-send-email-juri.lelli@arm.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
On Thu, Aug 14, 2014 at 09:27:45AM +0100, Juri Lelli wrote: > Commit af040ffc9ba1 ("ARM: make it easier to check the CPU part number > correctly") changed ARM_CPU_PART_X masks, and the way they are returned and > checked against. Usage of read_cpuid_part_number() is now deprecated, and > calling places updated accordingly. This actually broke cpuidle-big_little > initialization, as bl_idle_driver_init() performs a check using an hardcoded > mask on cpu_id. > > Create an interface to perform the check (that is now even easier to read). > Define also a proper mask (ARM_CPU_PART_MASK) that makes this kind of checks > cleaner and helps preventing bugs in the future. Update usage accordingly. If Russell does not have any additional comments you can send it to his patch system. Thanks, Lorenzo > Signed-off-by: Juri Lelli <juri.lelli@arm.com> > Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> > Cc: Russell King <linux@arm.linux.org.uk> > Cc: Daniel Lezcano <daniel.lezcano@linaro.org> > Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> > Cc: Will Deacon <will.deacon@arm.com> > Cc: Chao Xie <chao.xie@marvell.com> > Cc: Stephen Warren <swarren@nvidia.com> > Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> > Cc: Rob Herring <rob.herring@calxeda.com> > Cc: Jonathan Austin <Jonathan.Austin@arm.com> > Cc: Chao Xie Linux <xiechao.mail@gmail.com> > Cc: Juri Lelli <juri.lelli@gmail.com> > Cc: linux-pm@vger.kernel.org > Cc: linux-arm-kernel@lists.infradead.org > Cc: linux-kernel@vger.kernel.org > --- > arch/arm/include/asm/cputype.h | 3 ++- > arch/arm/include/asm/smp_plat.h | 15 +++++++++++++++ > drivers/cpuidle/cpuidle-big_little.c | 13 +++---------- > 3 files changed, 20 insertions(+), 11 deletions(-) > > diff --git a/arch/arm/include/asm/cputype.h b/arch/arm/include/asm/cputype.h > index 963a251..819777d 100644 > --- a/arch/arm/include/asm/cputype.h > +++ b/arch/arm/include/asm/cputype.h > @@ -74,6 +74,7 @@ > #define ARM_CPU_PART_CORTEX_A12 0x4100c0d0 > #define ARM_CPU_PART_CORTEX_A17 0x4100c0e0 > #define ARM_CPU_PART_CORTEX_A15 0x4100c0f0 > +#define ARM_CPU_PART_MASK 0xff00fff0 > > #define ARM_CPU_XSCALE_ARCH_MASK 0xe000 > #define ARM_CPU_XSCALE_ARCH_V1 0x2000 > @@ -179,7 +180,7 @@ static inline unsigned int __attribute_const__ read_cpuid_implementor(void) > */ > static inline unsigned int __attribute_const__ read_cpuid_part(void) > { > - return read_cpuid_id() & 0xff00fff0; > + return read_cpuid_id() & ARM_CPU_PART_MASK; > } > > static inline unsigned int __attribute_const__ __deprecated read_cpuid_part_number(void) > diff --git a/arch/arm/include/asm/smp_plat.h b/arch/arm/include/asm/smp_plat.h > index a252c0b..0ad7d49 100644 > --- a/arch/arm/include/asm/smp_plat.h > +++ b/arch/arm/include/asm/smp_plat.h > @@ -8,6 +8,7 @@ > #include <linux/cpumask.h> > #include <linux/err.h> > > +#include <asm/cpu.h> > #include <asm/cputype.h> > > /* > @@ -25,6 +26,20 @@ static inline bool is_smp(void) > #endif > } > > +/** > + * smp_cpuid_part() - return part id for a given cpu > + * @cpu: logical cpu id. > + * > + * Return: part id of logical cpu passed as argument. > + */ > +static inline unsigned int smp_cpuid_part(int cpu) > +{ > + struct cpuinfo_arm *cpu_info = &per_cpu(cpu_data, cpu); > + > + return is_smp() ? cpu_info->cpuid & ARM_CPU_PART_MASK : > + read_cpuid_part(); > +} > + > /* all SMP configurations have the extended CPUID registers */ > #ifndef CONFIG_MMU > #define tlb_ops_need_broadcast() 0 > diff --git a/drivers/cpuidle/cpuidle-big_little.c b/drivers/cpuidle/cpuidle-big_little.c > index 344d79fa..ef94c3b 100644 > --- a/drivers/cpuidle/cpuidle-big_little.c > +++ b/drivers/cpuidle/cpuidle-big_little.c > @@ -138,25 +138,18 @@ static int bl_enter_powerdown(struct cpuidle_device *dev, > return idx; > } > > -static int __init bl_idle_driver_init(struct cpuidle_driver *drv, int cpu_id) > +static int __init bl_idle_driver_init(struct cpuidle_driver *drv, int part_id) > { > - struct cpuinfo_arm *cpu_info; > struct cpumask *cpumask; > - unsigned long cpuid; > int cpu; > > cpumask = kzalloc(cpumask_size(), GFP_KERNEL); > if (!cpumask) > return -ENOMEM; > > - for_each_possible_cpu(cpu) { > - cpu_info = &per_cpu(cpu_data, cpu); > - cpuid = is_smp() ? cpu_info->cpuid : read_cpuid_id(); > - > - /* read cpu id part number */ > - if ((cpuid & 0xFFF0) == cpu_id) > + for_each_possible_cpu(cpu) > + if (smp_cpuid_part(cpu) == part_id) > cpumask_set_cpu(cpu, cpumask); > - } > > drv->cpumask = cpumask; > > -- > 2.0.4 >
Juri Lelli <juri.lelli@arm.com> writes: > Commit af040ffc9ba1 ("ARM: make it easier to check the CPU part number > correctly") changed ARM_CPU_PART_X masks, and the way they are returned and > checked against. Usage of read_cpuid_part_number() is now deprecated, and > calling places updated accordingly. This actually broke cpuidle-big_little > initialization, as bl_idle_driver_init() performs a check using an hardcoded > mask on cpu_id. > > Create an interface to perform the check (that is now even easier to read). > Define also a proper mask (ARM_CPU_PART_MASK) that makes this kind of checks > cleaner and helps preventing bugs in the future. Update usage accordingly. [...] Tested-by: Kevin Hilman <khilman@linaro.org> FWIW, I can confirm that this patch is needed for cpuidle-big_little to work on the Exynos5800/Chromebook2. Kevin
On 15/08/14 17:32, Kevin Hilman wrote: > Juri Lelli <juri.lelli@arm.com> writes: > >> Commit af040ffc9ba1 ("ARM: make it easier to check the CPU part number >> correctly") changed ARM_CPU_PART_X masks, and the way they are returned and >> checked against. Usage of read_cpuid_part_number() is now deprecated, and >> calling places updated accordingly. This actually broke cpuidle-big_little >> initialization, as bl_idle_driver_init() performs a check using an hardcoded >> mask on cpu_id. >> >> Create an interface to perform the check (that is now even easier to read). >> Define also a proper mask (ARM_CPU_PART_MASK) that makes this kind of checks >> cleaner and helps preventing bugs in the future. Update usage accordingly. > > [...] > > Tested-by: Kevin Hilman <khilman@linaro.org> > Great, thanks! > FWIW, I can confirm that this patch is needed for cpuidle-big_little to > work on the Exynos5800/Chromebook2. > Ok, the patch has been already sent to Russell's patch system. Best, - Juri > Kevin >
diff --git a/arch/arm/include/asm/cputype.h b/arch/arm/include/asm/cputype.h index 963a251..819777d 100644 --- a/arch/arm/include/asm/cputype.h +++ b/arch/arm/include/asm/cputype.h @@ -74,6 +74,7 @@ #define ARM_CPU_PART_CORTEX_A12 0x4100c0d0 #define ARM_CPU_PART_CORTEX_A17 0x4100c0e0 #define ARM_CPU_PART_CORTEX_A15 0x4100c0f0 +#define ARM_CPU_PART_MASK 0xff00fff0 #define ARM_CPU_XSCALE_ARCH_MASK 0xe000 #define ARM_CPU_XSCALE_ARCH_V1 0x2000 @@ -179,7 +180,7 @@ static inline unsigned int __attribute_const__ read_cpuid_implementor(void) */ static inline unsigned int __attribute_const__ read_cpuid_part(void) { - return read_cpuid_id() & 0xff00fff0; + return read_cpuid_id() & ARM_CPU_PART_MASK; } static inline unsigned int __attribute_const__ __deprecated read_cpuid_part_number(void) diff --git a/arch/arm/include/asm/smp_plat.h b/arch/arm/include/asm/smp_plat.h index a252c0b..0ad7d49 100644 --- a/arch/arm/include/asm/smp_plat.h +++ b/arch/arm/include/asm/smp_plat.h @@ -8,6 +8,7 @@ #include <linux/cpumask.h> #include <linux/err.h> +#include <asm/cpu.h> #include <asm/cputype.h> /* @@ -25,6 +26,20 @@ static inline bool is_smp(void) #endif } +/** + * smp_cpuid_part() - return part id for a given cpu + * @cpu: logical cpu id. + * + * Return: part id of logical cpu passed as argument. + */ +static inline unsigned int smp_cpuid_part(int cpu) +{ + struct cpuinfo_arm *cpu_info = &per_cpu(cpu_data, cpu); + + return is_smp() ? cpu_info->cpuid & ARM_CPU_PART_MASK : + read_cpuid_part(); +} + /* all SMP configurations have the extended CPUID registers */ #ifndef CONFIG_MMU #define tlb_ops_need_broadcast() 0 diff --git a/drivers/cpuidle/cpuidle-big_little.c b/drivers/cpuidle/cpuidle-big_little.c index 344d79fa..ef94c3b 100644 --- a/drivers/cpuidle/cpuidle-big_little.c +++ b/drivers/cpuidle/cpuidle-big_little.c @@ -138,25 +138,18 @@ static int bl_enter_powerdown(struct cpuidle_device *dev, return idx; } -static int __init bl_idle_driver_init(struct cpuidle_driver *drv, int cpu_id) +static int __init bl_idle_driver_init(struct cpuidle_driver *drv, int part_id) { - struct cpuinfo_arm *cpu_info; struct cpumask *cpumask; - unsigned long cpuid; int cpu; cpumask = kzalloc(cpumask_size(), GFP_KERNEL); if (!cpumask) return -ENOMEM; - for_each_possible_cpu(cpu) { - cpu_info = &per_cpu(cpu_data, cpu); - cpuid = is_smp() ? cpu_info->cpuid : read_cpuid_id(); - - /* read cpu id part number */ - if ((cpuid & 0xFFF0) == cpu_id) + for_each_possible_cpu(cpu) + if (smp_cpuid_part(cpu) == part_id) cpumask_set_cpu(cpu, cpumask); - } drv->cpumask = cpumask;