[PATCH v11 2/7] arm: arm64: Add routine to determine cpuid of other cpus

Jeremy Linton
2016-12-02T18:55:56Z

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 <jeremy.linton@arm.com>
---
arch/arm/include/asm/cputype.h | 4 ++++
arch/arm/kernel/setup.c | 2 +-
arch/arm64/include/asm/cputype.h | 3 +++
3 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/arch/arm/include/asm/cputype.h b/arch/arm/include/asm/cputype.h
index 522b5fe..1e87d06 100644
--- a/arch/arm/include/asm/cputype.h
+++ b/arch/arm/include/asm/cputype.h
@@ -235,6 +235,10 @@ static inline unsigned int __attribute_const__ read_cpuid_mpidr(void)
#define cpu_is_sa1100() (read_cpuid_part() == ARM_CPU_PART_SA1100)
#define cpu_is_sa1110() (read_cpuid_part() == ARM_CPU_PART_SA1110)

+#define read_specific_cpuid(cpu_num) (is_smp() ? \
+ per_cpu_ptr(&cpu_data, cpu_num)->cpuid \
+ : read_cpuid_id())
+
/*
* Intel's XScale3 core supports some v6 features (supersections, L2)
* but advertises itself as v5 as it does not support the v6 ISA. For
diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index 34e3f3c..d443c97 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -1217,7 +1217,7 @@ static int c_show(struct seq_file *m, void *v)
* "processor". Give glibc what it expects.
*/
seq_printf(m, "processor\t: %d\n", i);
- cpuid = is_smp() ? per_cpu(cpu_data, i).cpuid : read_cpuid_id();
+ cpuid = read_specific_cpuid(i);
seq_printf(m, "model name\t: %s rev %d (%s)\n",
cpu_name, cpuid & 15, elf_platform);

diff --git a/arch/arm64/include/asm/cputype.h b/arch/arm64/include/asm/cputype.h
index 26a68dd..a6d26e1 100644
--- a/arch/arm64/include/asm/cputype.h
+++ b/arch/arm64/include/asm/cputype.h
@@ -124,6 +124,9 @@ static inline u32 __attribute_const__ read_cpuid_cachetype(void)
{
return read_cpuid(CTR_EL0);
}
+
+#define read_specific_cpuid(cpu_num) per_cpu_ptr(&cpu_data, cpu_num)->reg_midr
+
#endif /* __ASSEMBLY__ */

#endif
--
2.5.5