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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/x86/kernel/cpu/scattered.c
Initial import
Diffstat (limited to 'arch/x86/kernel/cpu/scattered.c')
-rw-r--r--arch/x86/kernel/cpu/scattered.c77
1 files changed, 77 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c
new file mode 100644
index 000000000..3d423a101
--- /dev/null
+++ b/arch/x86/kernel/cpu/scattered.c
@@ -0,0 +1,77 @@
+/*
+ * Routines to identify 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 init_scattered_cpuid_features(struct cpuinfo_x86 *c)
+{
+ u32 max_level;
+ u32 regs[4];
+ const struct cpuid_bit *cb;
+
+ static const struct cpuid_bit cpuid_bits[] = {
+ { X86_FEATURE_DTHERM, CR_EAX, 0, 0x00000006, 0 },
+ { 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_HWP, CR_EAX, 7, 0x00000006, 0 },
+ { X86_FEATURE_HWP_NOITFY, CR_EAX, 8, 0x00000006, 0 },
+ { X86_FEATURE_HWP_ACT_WINDOW, CR_EAX, 9, 0x00000006, 0 },
+ { X86_FEATURE_HWP_EPP, CR_EAX,10, 0x00000006, 0 },
+ { X86_FEATURE_HWP_PKG_REQ, CR_EAX,11, 0x00000006, 0 },
+ { X86_FEATURE_INTEL_PT, CR_EBX,25, 0x00000007, 0 },
+ { X86_FEATURE_APERFMPERF, CR_ECX, 0, 0x00000006, 0 },
+ { X86_FEATURE_EPB, CR_ECX, 3, 0x00000006, 0 },
+ { X86_FEATURE_HW_PSTATE, CR_EDX, 7, 0x80000007, 0 },
+ { X86_FEATURE_CPB, CR_EDX, 9, 0x80000007, 0 },
+ { X86_FEATURE_PROC_FEEDBACK, CR_EDX,11, 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 },
+ { X86_FEATURE_TSCRATEMSR, CR_EDX, 4, 0x8000000a, 0 },
+ { X86_FEATURE_VMCBCLEAN, CR_EDX, 5, 0x8000000a, 0 },
+ { X86_FEATURE_FLUSHBYASID, CR_EDX, 6, 0x8000000a, 0 },
+ { X86_FEATURE_DECODEASSISTS, CR_EDX, 7, 0x8000000a, 0 },
+ { X86_FEATURE_PAUSEFILTER, CR_EDX,10, 0x8000000a, 0 },
+ { X86_FEATURE_PFTHRESHOLD, CR_EDX,12, 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);
+ }
+}