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authorJuri Lelli <juri.lelli@arm.com>2014-08-15 16:53:14 +0200
committerRussell King <rmk+kernel@arm.linux.org.uk>2014-08-27 16:40:45 +0200
commiteba1c71819d210f5e0d522571f9b8abce94fe9c5 (patch)
tree9ce0c82dc16f8f20caecb76956b234377de52a6a /arch/arm
parentARM: 8129/1: errata: work around Cortex-A15 erratum 830321 using dummy strex (diff)
downloadlinux-eba1c71819d210f5e0d522571f9b8abce94fe9c5.tar.xz
linux-eba1c71819d210f5e0d522571f9b8abce94fe9c5.zip
ARM: 8130/1: cpuidle/cpuidle-big_little: fix reading cpu id part number
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. Signed-off-by: Juri Lelli <juri.lelli@arm.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm')
-rw-r--r--arch/arm/include/asm/cputype.h3
-rw-r--r--arch/arm/include/asm/smp_plat.h15
2 files changed, 17 insertions, 1 deletions
diff --git a/arch/arm/include/asm/cputype.h b/arch/arm/include/asm/cputype.h
index 963a2515906d..819777d0e91f 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 a252c0bfacf5..0ad7d490ee6f 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