diff options
author | H. Peter Anvin <hpa@linux.intel.com> | 2010-07-19 18:32:04 -0700 |
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committer | H. Peter Anvin <hpa@linux.intel.com> | 2010-07-19 19:02:41 -0700 |
commit | 2decb194e65ab66eaf787512dc572cdc99893b24 (patch) | |
tree | 80e1df44c19b28487bfc663300ca58236505bc70 /arch/x86/kernel/cpu/topology.c | |
parent | 278bc5f6abd69dd868746dbd642266ac09a9c9c6 (diff) | |
download | linux-2decb194e65ab66eaf787512dc572cdc99893b24.tar.bz2 |
x86, cpu: Split addon_cpuid_features.c
addon_cpuid_features.c contains exactly two almost completely
unrelated functions, plus has a long and very generic name. Split it
into two files, scattered.c for the scattered feature flags, and
topology.c for the topology information.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
LKML-Reference: <tip-*@git.kernel.org>
Diffstat (limited to 'arch/x86/kernel/cpu/topology.c')
-rw-r--r-- | arch/x86/kernel/cpu/topology.c | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/topology.c b/arch/x86/kernel/cpu/topology.c new file mode 100644 index 000000000000..4397e987a1cf --- /dev/null +++ b/arch/x86/kernel/cpu/topology.c @@ -0,0 +1,99 @@ +/* + * Check for extended topology enumeration cpuid leaf 0xb and if it + * exists, use it for populating initial_apicid and cpu topology + * detection. + */ + +#include <linux/cpu.h> +#include <asm/apic.h> +#include <asm/pat.h> +#include <asm/processor.h> + +/* leaf 0xb SMT level */ +#define SMT_LEVEL 0 + +/* leaf 0xb sub-leaf types */ +#define INVALID_TYPE 0 +#define SMT_TYPE 1 +#define CORE_TYPE 2 + +#define LEAFB_SUBTYPE(ecx) (((ecx) >> 8) & 0xff) +#define BITS_SHIFT_NEXT_LEVEL(eax) ((eax) & 0x1f) +#define LEVEL_MAX_SIBLINGS(ebx) ((ebx) & 0xffff) + +/* + * Check for extended topology enumeration cpuid leaf 0xb and if it + * exists, use it for populating initial_apicid and cpu topology + * detection. + */ +void __cpuinit detect_extended_topology(struct cpuinfo_x86 *c) +{ +#ifdef CONFIG_SMP + unsigned int eax, ebx, ecx, edx, sub_index; + unsigned int ht_mask_width, core_plus_mask_width; + unsigned int core_select_mask, core_level_siblings; + static bool printed; + + if (c->cpuid_level < 0xb) + return; + + cpuid_count(0xb, SMT_LEVEL, &eax, &ebx, &ecx, &edx); + + /* + * check if the cpuid leaf 0xb is actually implemented. + */ + if (ebx == 0 || (LEAFB_SUBTYPE(ecx) != SMT_TYPE)) + return; + + set_cpu_cap(c, X86_FEATURE_XTOPOLOGY); + + /* + * initial apic id, which also represents 32-bit extended x2apic id. + */ + c->initial_apicid = edx; + + /* + * Populate HT related information from sub-leaf level 0. + */ + core_level_siblings = smp_num_siblings = LEVEL_MAX_SIBLINGS(ebx); + core_plus_mask_width = ht_mask_width = BITS_SHIFT_NEXT_LEVEL(eax); + + sub_index = 1; + do { + cpuid_count(0xb, sub_index, &eax, &ebx, &ecx, &edx); + + /* + * Check for the Core type in the implemented sub leaves. + */ + if (LEAFB_SUBTYPE(ecx) == CORE_TYPE) { + core_level_siblings = LEVEL_MAX_SIBLINGS(ebx); + core_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax); + break; + } + + sub_index++; + } while (LEAFB_SUBTYPE(ecx) != INVALID_TYPE); + + core_select_mask = (~(-1 << core_plus_mask_width)) >> ht_mask_width; + + c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid, ht_mask_width) + & core_select_mask; + c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid, core_plus_mask_width); + /* + * Reinit the apicid, now that we have extended initial_apicid. + */ + c->apicid = apic->phys_pkg_id(c->initial_apicid, 0); + + c->x86_max_cores = (core_level_siblings / smp_num_siblings); + + if (!printed) { + printk(KERN_INFO "CPU: Physical Processor ID: %d\n", + c->phys_proc_id); + if (c->x86_max_cores > 1) + printk(KERN_INFO "CPU: Processor Core ID: %d\n", + c->cpu_core_id); + printed = 1; + } + return; +#endif +} |