[MODERN FEATURES] CPUID and MSR

kernel/arch/msr.c

@@ -0,0 +1,13 @@
+#include <stdint.h>
+
+uint64_t msr_read(uint32_t msr)
+{
+  uint64_t lo, hi;
+  asm volatile("rdmsr" : "=a"(lo), "=d"(hi) : "c"(msr));
+  return ((hi&0xFFFFFFFF) << 32) | (lo&0xFFFFFFFF);
+}
+
+void msr_write(uint32_t msr, uint64_t value)
+{
+  asm volatile("wrmsr" : : "a" (value&0xFFFFFFFF), "d"(value>>32), "c"(msr));
+}