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-rw-r--r--arch/x86/kernel/cpu/scattered.c73
1 files changed, 73 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c
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+++ b/arch/x86/kernel/cpu/scattered.c
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+/*
+ * Routines to identify additional cpu features that are scattered in
+ * cpuid space.
+ */
+#include <linux/cpu.h>
+
+#include <asm/memtype.h>
+#include <asm/apic.h>
+#include <asm/processor.h>
+
+#include "cpu.h"
+
+struct cpuid_bit {
+ u16 feature;
+ u8 reg;
+ u8 bit;
+ u32 level;
+ u32 sub_leaf;
+};
+
+/*
+ * Please keep the leaf sorted by cpuid_bit.level for faster search.
+ * X86_FEATURE_MBA is supported by both Intel and AMD. But the CPUID
+ * levels are different and there is a separate entry for each.
+ */
+static const struct cpuid_bit cpuid_bits[] = {
+ { X86_FEATURE_APERFMPERF, CPUID_ECX, 0, 0x00000006, 0 },
+ { X86_FEATURE_EPB, CPUID_ECX, 3, 0x00000006, 0 },
+ { X86_FEATURE_INTEL_PPIN, CPUID_EBX, 0, 0x00000007, 1 },
+ { X86_FEATURE_RRSBA_CTRL, CPUID_EDX, 2, 0x00000007, 2 },
+ { X86_FEATURE_CQM_LLC, CPUID_EDX, 1, 0x0000000f, 0 },
+ { X86_FEATURE_CQM_OCCUP_LLC, CPUID_EDX, 0, 0x0000000f, 1 },
+ { X86_FEATURE_CQM_MBM_TOTAL, CPUID_EDX, 1, 0x0000000f, 1 },
+ { X86_FEATURE_CQM_MBM_LOCAL, CPUID_EDX, 2, 0x0000000f, 1 },
+ { X86_FEATURE_CAT_L3, CPUID_EBX, 1, 0x00000010, 0 },
+ { X86_FEATURE_CAT_L2, CPUID_EBX, 2, 0x00000010, 0 },
+ { X86_FEATURE_CDP_L3, CPUID_ECX, 2, 0x00000010, 1 },
+ { X86_FEATURE_CDP_L2, CPUID_ECX, 2, 0x00000010, 2 },
+ { X86_FEATURE_MBA, CPUID_EBX, 3, 0x00000010, 0 },
+ { X86_FEATURE_PER_THREAD_MBA, CPUID_ECX, 0, 0x00000010, 3 },
+ { X86_FEATURE_SGX1, CPUID_EAX, 0, 0x00000012, 0 },
+ { X86_FEATURE_SGX2, CPUID_EAX, 1, 0x00000012, 0 },
+ { X86_FEATURE_HW_PSTATE, CPUID_EDX, 7, 0x80000007, 0 },
+ { X86_FEATURE_CPB, CPUID_EDX, 9, 0x80000007, 0 },
+ { X86_FEATURE_PROC_FEEDBACK, CPUID_EDX, 11, 0x80000007, 0 },
+ { X86_FEATURE_MBA, CPUID_EBX, 6, 0x80000008, 0 },
+ { X86_FEATURE_PERFMON_V2, CPUID_EAX, 0, 0x80000022, 0 },
+ { X86_FEATURE_AMD_LBR_V2, CPUID_EAX, 1, 0x80000022, 0 },
+ { 0, 0, 0, 0, 0 }
+};
+
+void init_scattered_cpuid_features(struct cpuinfo_x86 *c)
+{
+ u32 max_level;
+ u32 regs[4];
+ const struct cpuid_bit *cb;
+
+ for (cb = cpuid_bits; cb->feature; cb++) {
+
+ /* Verify that the level is valid */
+ max_level = cpuid_eax(cb->level & 0xffff0000);
+ if (max_level < cb->level ||
+ max_level > (cb->level | 0xffff))
+ continue;
+
+ cpuid_count(cb->level, cb->sub_leaf, &regs[CPUID_EAX],
+ &regs[CPUID_EBX], &regs[CPUID_ECX],
+ &regs[CPUID_EDX]);
+
+ if (regs[cb->reg] & (1 << cb->bit))
+ set_cpu_cap(c, cb->feature);
+ }
+}