On 07/06/2016 11:30 AM, Will Deacon wrote:

On Tue, Jun 21, 2016 at 12:11:44PM -0500, Jeremy Linton wrote:

quoted

It is helpful if we can read the cpuid/midr of other CPUs
in the system independent of arm/arm64.

Signed-off-by: Jeremy Linton <redacted>
---
  arch/arm/include/asm/cputype.h   | 6 +++++-
  arch/arm64/include/asm/cputype.h | 4 ++++
  2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/arch/arm/include/asm/cputype.h b/arch/arm/include/asm/cputype.h
index 1ee94c7..e391b67 100644
--- a/arch/arm/include/asm/cputype.h
+++ b/arch/arm/include/asm/cputype.h

@@ -81,6 +81,8 @@
  #define ARM_CPU_XSCALE_ARCH_V2		0x4000
  #define ARM_CPU_XSCALE_ARCH_V3		0x6000

+#define ARM_PARTNUM(cpuid_id) (cpuid_id & ARM_CPU_PART_MASK)
+
  extern unsigned int processor_id;

  #ifdef CONFIG_CPU_CP15

@@ -180,7 +182,7 @@ static inline unsigned int __attribute_const__ read_cpuid_implementor(void)
   */
  static inline unsigned int __attribute_const__ read_cpuid_part(void)
  {
-	return read_cpuid_id() & ARM_CPU_PART_MASK;
+	return ARM_PARTNUM(read_cpuid_id());

I don't understand why you need to make this change.

The short answer is that the ARM_PARTNUM stuff is left over from v4 (?) 
of the patch, where it seemed a good idea to create a macro that was 
arm/arm64 independent for use in arm_pmu.c. Somewhere along there I 
reverted the ARM_PARTNUM to MIDR_PARTNUM in the arm_pmu_acpi.c but 
didn't drop that portion from this patch. Partially because it seems 
like a good idea. OTOH, your right probably doesn't belong here without 
the large cleanup which would form their own patch set.