x86/boot: Detect 5-level paging support

[people/arne_f/kernel.git] / arch / x86 / boot / cpuflags.c

diff --git a/arch/x86/boot/cpuflags.c b/arch/x86/boot/cpuflags.c
index 6687ab9532575bf1d52fac34809fb94a040613f7..9e77c23c242268482e413da37af5f1835780dc1f 100644 (file)
--- a/arch/x86/boot/cpuflags.c
+++ b/arch/x86/boot/cpuflags.c
@@ -70,16 +70,19 @@ int has_eflag(unsigned long mask)
 # define EBX_REG "=b"
 #endif
 
-static inline void cpuid(u32 id, u32 *a, u32 *b, u32 *c, u32 *d)
+static inline void cpuid_count(u32 id, u32 count,
+               u32 *a, u32 *b, u32 *c, u32 *d)
 {
        asm volatile(".ifnc %%ebx,%3 ; movl  %%ebx,%3 ; .endif  \n\t"
                     "cpuid                                     \n\t"
                     ".ifnc %%ebx,%3 ; xchgl %%ebx,%3 ; .endif  \n\t"
                    : "=a" (*a), "=c" (*c), "=d" (*d), EBX_REG (*b)
-                   : "a" (id)
+                   : "a" (id), "c" (count)
        );
 }
 
+#define cpuid(id, a, b, c, d) cpuid_count(id, 0, a, b, c, d)
+
 void get_cpuflags(void)
 {
        u32 max_intel_level, max_amd_level;
@@ -108,6 +111,11 @@ void get_cpuflags(void)
                                cpu.model += ((tfms >> 16) & 0xf) << 4;
                }
 
+               if (max_intel_level >= 0x00000007) {
+                       cpuid_count(0x00000007, 0, &ignored, &ignored,
+                                       &cpu.flags[16], &ignored);
+               }
+
                cpuid(0x80000000, &max_amd_level, &ignored, &ignored,
                      &ignored);