summaryrefslogtreecommitdiffstats
path: root/arch/x86/kernel/cpu/addon_cpuid_features.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kernel/cpu/addon_cpuid_features.c')
-rw-r--r--arch/x86/kernel/cpu/addon_cpuid_features.c122
1 files changed, 111 insertions, 11 deletions
diff --git a/arch/x86/kernel/cpu/addon_cpuid_features.c b/arch/x86/kernel/cpu/addon_cpuid_features.c
index c2e1ce3..0d9c993 100644
--- a/arch/x86/kernel/cpu/addon_cpuid_features.c
+++ b/arch/x86/kernel/cpu/addon_cpuid_features.c
@@ -1,14 +1,14 @@
-
/*
* Routines to indentify additional cpu features that are scattered in
* cpuid space.
*/
-
#include <linux/cpu.h>
#include <asm/pat.h>
#include <asm/processor.h>
+#include <mach_apic.h>
+
struct cpuid_bit {
u16 feature;
u8 reg;
@@ -50,22 +50,122 @@ void __cpuinit init_scattered_cpuid_features(struct cpuinfo_x86 *c)
}
}
+/* 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;
+
+ 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;
+
+#ifdef CONFIG_X86_32
+ c->cpu_core_id = phys_pkg_id(c->initial_apicid, ht_mask_width)
+ & core_select_mask;
+ c->phys_proc_id = phys_pkg_id(c->initial_apicid, core_plus_mask_width);
+#else
+ c->cpu_core_id = phys_pkg_id(ht_mask_width) & core_select_mask;
+ c->phys_proc_id = phys_pkg_id(core_plus_mask_width);
+#endif
+ c->x86_max_cores = (core_level_siblings / smp_num_siblings);
+
+
+ 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);
+ return;
+#endif
+}
+
#ifdef CONFIG_X86_PAT
void __cpuinit validate_pat_support(struct cpuinfo_x86 *c)
{
+ if (!cpu_has_pat)
+ pat_disable("PAT not supported by CPU.");
+
switch (c->x86_vendor) {
- case X86_VENDOR_AMD:
- if (c->x86 >= 0xf && c->x86 <= 0x11)
- return;
- break;
case X86_VENDOR_INTEL:
- if (c->x86 == 0xF || (c->x86 == 6 && c->x86_model >= 15))
+ /*
+ * There is a known erratum on Pentium III and Core Solo
+ * and Core Duo CPUs.
+ * " Page with PAT set to WC while associated MTRR is UC
+ * may consolidate to UC "
+ * Because of this erratum, it is better to stick with
+ * setting WC in MTRR rather than using PAT on these CPUs.
+ *
+ * Enable PAT WC only on P4, Core 2 or later CPUs.
+ */
+ if (c->x86 > 0x6 || (c->x86 == 6 && c->x86_model >= 15))
return;
- break;
+
+ pat_disable("PAT WC disabled due to known CPU erratum.");
+ return;
+
+ case X86_VENDOR_AMD:
+ case X86_VENDOR_CENTAUR:
+ case X86_VENDOR_TRANSMETA:
+ return;
}
- pat_disable(cpu_has_pat ?
- "PAT disabled. Not yet verified on this CPU type." :
- "PAT not supported by CPU.");
+ pat_disable("PAT disabled. Not yet verified on this CPU type.");
}
#endif
OpenPOWER on IntegriCloud