[RFC PATCH v2 1/2] ARM: kernel: add MIDR to per-CPU information data

[Lorenzo Pieralisi]

The advent of big.LITTLE ARM platforms requires the kernel to be able
to identify the MIDRs of all online CPUs upon request. MIDRs are stashed
at boot time so that kernel subsystems can detect the MIDR of online CPUs
by simply retrieving per-CPU data updated by all booted CPUs.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi at arm.com>
---
 arch/arm/include/asm/cpu.h | 1 +
 arch/arm/kernel/smp.c      | 1 +
 2 files changed, 2 insertions(+)

diff --git a/arch/arm/include/asm/cpu.h b/arch/arm/include/asm/cpu.h
index d797223..2744f06 100644
--- a/arch/arm/include/asm/cpu.h
+++ b/arch/arm/include/asm/cpu.h
@@ -15,6 +15,7 @@
 
 struct cpuinfo_arm {
 	struct cpu	cpu;
+	u32		cpuid;
 #ifdef CONFIG_SMP
 	unsigned int	loops_per_jiffy;
 #endif
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index 9da08ce..eeb75e1 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -282,6 +282,7 @@ static void __cpuinit smp_store_cpu_info(unsigned int cpuid)
 	struct cpuinfo_arm *cpu_info = &per_cpu(cpu_data, cpuid);
 
 	cpu_info->loops_per_jiffy = loops_per_jiffy;
+	cpu_info->cpuid = read_cpuid_id();
 
 	store_cpu_topology(cpuid);
 }
-- 
1.7.12