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Diffstat (limited to 'arch/x86/kernel/cpu/scattered.c')
-rw-r--r--arch/x86/kernel/cpu/scattered.c63
1 files changed, 63 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c
new file mode 100644
index 000000000000..34b4dad6f0b8
--- /dev/null
+++ b/arch/x86/kernel/cpu/scattered.c
@@ -0,0 +1,63 @@
+/*
+ * 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 <asm/apic.h>
+
+struct cpuid_bit {
+ u16 feature;
+ u8 reg;
+ u8 bit;
+ u32 level;
+ u32 sub_leaf;
+};
+
+enum cpuid_regs {
+ CR_EAX = 0,
+ CR_ECX,
+ CR_EDX,
+ CR_EBX
+};
+
+void __cpuinit init_scattered_cpuid_features(struct cpuinfo_x86 *c)
+{
+ u32 max_level;
+ u32 regs[4];
+ const struct cpuid_bit *cb;
+
+ static const struct cpuid_bit __cpuinitconst cpuid_bits[] = {
+ { X86_FEATURE_IDA, CR_EAX, 1, 0x00000006, 0 },
+ { X86_FEATURE_ARAT, CR_EAX, 2, 0x00000006, 0 },
+ { X86_FEATURE_PLN, CR_EAX, 4, 0x00000006, 0 },
+ { X86_FEATURE_PTS, CR_EAX, 6, 0x00000006, 0 },
+ { X86_FEATURE_APERFMPERF, CR_ECX, 0, 0x00000006, 0 },
+ { X86_FEATURE_EPB, CR_ECX, 3, 0x00000006, 0 },
+ { X86_FEATURE_XSAVEOPT, CR_EAX, 0, 0x0000000d, 1 },
+ { X86_FEATURE_CPB, CR_EDX, 9, 0x80000007, 0 },
+ { X86_FEATURE_NPT, CR_EDX, 0, 0x8000000a, 0 },
+ { X86_FEATURE_LBRV, CR_EDX, 1, 0x8000000a, 0 },
+ { X86_FEATURE_SVML, CR_EDX, 2, 0x8000000a, 0 },
+ { X86_FEATURE_NRIPS, CR_EDX, 3, 0x8000000a, 0 },
+ { 0, 0, 0, 0, 0 }
+ };
+
+ 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[CR_EAX],
+ &regs[CR_EBX], &regs[CR_ECX], &regs[CR_EDX]);
+
+ if (regs[cb->reg] & (1 << cb->bit))
+ set_cpu_cap(c, cb->feature);
+ }
+}