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Intel CPUs: Fix counting of CPU cores

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Detection for a hyper-threading CPU was not compatible with multicore
CPUs. When using CPUID eax==4, also need to set ecx=0.

CAR init tested on real hardware with hyper-threading model_f25 and
under qemu 0.15.1 with multicore CPU.

Change-Id: I28ac8790f94652e4ba8ff88fe7812c812f967608
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/1172
Tested-by: build bot (Jenkins)
Reviewed-by: Anton Kochkov <anton.kochkov@gmail.com>
This commit is contained in:
Kyösti Mälkki
2012-07-04 12:02:58 +03:00
committed by Anton Kochkov
parent 15cf0adc3e
commit df0fbc7455
2 changed files with 32 additions and 9 deletions
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7
src/cpu/intel/hyperthreading/intel_sibling.c
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@@ -28,8 +28,11 @@ int intel_ht_sibling(void)
apic_ids = 1;
core_ids = 1;
if (cpuid_eax(0) >= 4)
core_ids += (cpuid_eax(4) >> 26) & 0x3f;
if (cpuid_eax(0) >= 4) {
struct cpuid_result result;
result = cpuid_ext(4, 0);
core_ids += (result.eax >> 26) & 0x3f;
}
threads = (apic_ids / core_ids);
return !!(lapicid() & (threads-1));