include/asm-x86/acpi.h

   1 #ifndef _ASM_X86_ACPI_H
   2 #define _ASM_X86_ACPI_H
   3
   4 #ifdef CONFIG_X86_32
   5 # include "acpi_32.h"
   6 #else
   7 # include "acpi_64.h"
   8 #endif
   9
  10 #include <asm/processor.h>
  11
  12 /*
  13  * Check if the CPU can handle C2 and deeper
  14  */
  15 static inline unsigned int acpi_processor_cstate_check(unsigned int max_cstate)
  16 {
  17         /*
  18          * Early models (<=5) of AMD Opterons are not supposed to go into
  19          * C2 state.
  20          *
  21          * Steppings 0x0A and later are good
  22          */
  23         if (boot_cpu_data.x86 == 0x0F &&
  24             boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
  25             boot_cpu_data.x86_model <= 0x05 &&
  26             boot_cpu_data.x86_mask < 0x0A)
  27                 return 1;
  28         else
  29                 return max_cstate;
  30 }
  31
  32 #endif