x86, cacheinfo: Determine number of cache leafs using CPUID 0x8000001d on AMD
CPUID 0x8000001d works quite similar to Intels' CPUID function 4.
Use it to determine number of cache leafs.
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Link: http://lkml.kernel.org/r/20121019085933.GE26718@alberich
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
diff --git a/arch/x86/kernel/cpu/intel_cacheinfo.c b/arch/x86/kernel/cpu/intel_cacheinfo.c
index 93c5451..8ce7a83 100644
--- a/arch/x86/kernel/cpu/intel_cacheinfo.c
+++ b/arch/x86/kernel/cpu/intel_cacheinfo.c
@@ -557,21 +557,39 @@
return 0;
}
-static int __cpuinit find_num_cache_leaves(void)
+static int __cpuinit find_num_cache_leaves(struct cpuinfo_x86 *c)
{
- unsigned int eax, ebx, ecx, edx;
+ unsigned int eax, ebx, ecx, edx, op;
union _cpuid4_leaf_eax cache_eax;
int i = -1;
+ if (c->x86_vendor == X86_VENDOR_AMD)
+ op = 0x8000001d;
+ else
+ op = 4;
+
do {
++i;
- /* Do cpuid(4) loop to find out num_cache_leaves */
- cpuid_count(4, i, &eax, &ebx, &ecx, &edx);
+ /* Do cpuid(op) loop to find out num_cache_leaves */
+ cpuid_count(op, i, &eax, &ebx, &ecx, &edx);
cache_eax.full = eax;
} while (cache_eax.split.type != CACHE_TYPE_NULL);
return i;
}
+void __cpuinit init_amd_cacheinfo(struct cpuinfo_x86 *c)
+{
+
+ if (cpu_has_topoext) {
+ num_cache_leaves = find_num_cache_leaves(c);
+ } else if (c->extended_cpuid_level >= 0x80000006) {
+ if (cpuid_edx(0x80000006) & 0xf000)
+ num_cache_leaves = 4;
+ else
+ num_cache_leaves = 3;
+ }
+}
+
unsigned int __cpuinit init_intel_cacheinfo(struct cpuinfo_x86 *c)
{
/* Cache sizes */
@@ -588,7 +606,7 @@
if (is_initialized == 0) {
/* Init num_cache_leaves from boot CPU */
- num_cache_leaves = find_num_cache_leaves();
+ num_cache_leaves = find_num_cache_leaves(c);
is_initialized++;
}