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>

1 files changed, 23 insertions, 5 deletions

diff --git a/arch/x86/kernel/cpu/intel_cacheinfo.c b/arch/x86/kernel/cpu/intel_cacheinfo.c
index 93c5451bdd52..8ce7a83252f9 100644
--- a/arch/x86/kernel/cpu/intel_cacheinfo.c
+++ b/arch/x86/kernel/cpu/intel_cacheinfo.c
@@ -557,21 +557,39 @@ __cpuinit cpuid4_cache_lookup_regs(int index,
         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 @@ unsigned int __cpuinit init_intel_cacheinfo(struct cpuinfo_x86 *c)
 
                 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++;
                 }