diff options
author | Catalin Marinas <catalin.marinas@arm.com> | 2007-09-25 16:49:45 +0100 |
---|---|---|
committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2007-10-12 23:43:27 +0100 |
commit | 180005c4efb76a81fd0abcef4c2412d238eea20c (patch) | |
tree | fbc9e78fce9c9c071d97e59a77a9e2fb8d7c3c1a /arch | |
parent | c1f438f5eec867707022e5f33bec5e91ec12f6e7 (diff) |
[ARM] 4585/1: Correctly identify the CPU architecture version
The cpu_architecture() function in arch/arm/kernel/setup.c only works
with cores produced by ARM Ltd. The more generic approach is to read
the ID_MMFR0 register and check for the VMSA or PMSA version
supported. With this patch, the ARM11MPCore would be reported as ARMv7
since its MMU is compatible with ARMv7.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/arm/kernel/setup.c | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index 4de432ec903..efac7df72d6 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -304,10 +304,23 @@ int cpu_architecture(void) cpu_arch = (processor_id >> 16) & 7; if (cpu_arch) cpu_arch += CPU_ARCH_ARMv3; - } else { - /* the revised CPUID */ - cpu_arch = ((processor_id >> 12) & 0xf) - 0xb + CPU_ARCH_ARMv6; - } + } else if ((processor_id & 0x000f0000) == 0x000f0000) { + unsigned int mmfr0; + + /* Revised CPUID format. Read the Memory Model Feature + * Register 0 and check for VMSAv7 or PMSAv7 */ + asm("mrc p15, 0, %0, c0, c1, 4" + : "=r" (mmfr0)); + if ((mmfr0 & 0x0000000f) == 0x00000003 || + (mmfr0 & 0x000000f0) == 0x00000030) + cpu_arch = CPU_ARCH_ARMv7; + else if ((mmfr0 & 0x0000000f) == 0x00000002 || + (mmfr0 & 0x000000f0) == 0x00000020) + cpu_arch = CPU_ARCH_ARMv6; + else + cpu_arch = CPU_ARCH_UNKNOWN; + } else + cpu_arch = CPU_ARCH_UNKNOWN; return cpu_arch; } |