[PATCH 5/5] x86, cacheinfo, amd: fix reported cache parameters for family 0x10

From: Hans Rosenfeld
Date: Thu Jun 07 2012 - 12:46:41 EST


Family 0x10 RevD and later can use a part of the L3 cache as probe
filter. The size information from CPUID leaf 8000_0006 takes this into
account, but the reported associativity does not. The result are weird
values for ways_of_associativity and number_of_sets.

This patch fixes this for the affected models of family 0x10.

Signed-off-by: Hans Rosenfeld <hans.rosenfeld@xxxxxxx>
---
arch/x86/kernel/cpu/amd_cacheinfo.c | 11 ++++++++++-
arch/x86/kernel/cpu/cacheinfo.c | 4 ++--
arch/x86/kernel/cpu/cacheinfo.h | 3 ++-
3 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/cpu/amd_cacheinfo.c b/arch/x86/kernel/cpu/amd_cacheinfo.c
index e3fda975..5f77600 100644
--- a/arch/x86/kernel/cpu/amd_cacheinfo.c
+++ b/arch/x86/kernel/cpu/amd_cacheinfo.c
@@ -71,7 +71,8 @@ static const unsigned char __cpuinitconst types[] = { 1, 2, 3, 3 };
void __cpuinit amd_cpuid4(int leaf,
union _cpuid_cacheinfo_eax *eax,
union _cpuid_cacheinfo_ebx *ebx,
- union _cpuid_cacheinfo_ecx *ecx)
+ union _cpuid_cacheinfo_ecx *ecx,
+ struct amd_northbridge *nb)
{
unsigned dummy;
unsigned line_size, lines_per_tag, assoc, size_in_kb;
@@ -118,6 +119,14 @@ void __cpuinit amd_cpuid4(int leaf,
size_in_kb = size_in_kb >> 1;
assoc = assoc >> 1;
}
+ /* reduce associativity by amount used by probe filter */
+ if (boot_cpu_data.x86 == 0x10 && boot_cpu_data.x86_model >= 8 &&
+ nb != NULL) {
+ unsigned int reg;
+ pci_read_config_dword(nb->misc, 0x1d4, &reg);
+ if ((reg & 0x3))
+ assoc -= 8;
+ }
break;
default:
return;
diff --git a/arch/x86/kernel/cpu/cacheinfo.c b/arch/x86/kernel/cpu/cacheinfo.c
index db04501..9f879bf 100644
--- a/arch/x86/kernel/cpu/cacheinfo.c
+++ b/arch/x86/kernel/cpu/cacheinfo.c
@@ -27,12 +27,12 @@ int __cpuinit cpuid_cacheinfo_lookup_regs(int index,

if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
#if defined(CONFIG_CPU_SUP_AMD)
+ amd_init_l3_cache(this_leaf, index);
if (cpu_has_topoext)
cpuid_count(0x8000001d, index, &eax.full, &ebx.full,
&ecx.full, &edx);
else
- amd_cpuid4(index, &eax, &ebx, &ecx);
- amd_init_l3_cache(this_leaf, index);
+ amd_cpuid4(index, &eax, &ebx, &ecx, this_leaf->nb);
#endif
} else {
#if defined(CONFIG_CPU_SUP_INTEL)
diff --git a/arch/x86/kernel/cpu/cacheinfo.h b/arch/x86/kernel/cpu/cacheinfo.h
index fe39da7..104f818 100644
--- a/arch/x86/kernel/cpu/cacheinfo.h
+++ b/arch/x86/kernel/cpu/cacheinfo.h
@@ -66,7 +66,8 @@ struct _cache_attr {
extern struct attribute ** amd_l3_attrs(struct attribute **);
extern void amd_cpuid4(int, union _cpuid_cacheinfo_eax *,
union _cpuid_cacheinfo_ebx *,
- union _cpuid_cacheinfo_ecx *);
+ union _cpuid_cacheinfo_ecx *,
+ struct amd_northbridge *nb);
extern void amd_init_l3_cache(struct _cpuid_cacheinfo_regs *, int);
extern void cache_shared_amd_cpu_map_setup(unsigned int, int);
extern void cache_shared_intel_cpu_map_setup(unsigned int, int);
--
1.7.7


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