arch/arm/include/asm/cputype.h

   1 #ifndef __ASM_ARM_CPUTYPE_H
   2 #define __ASM_ARM_CPUTYPE_H
   3
   4 #include <linux/stringify.h>
   5
   6 #define CPUID_ID        0
   7 #define CPUID_CACHETYPE 1
   8 #define CPUID_TCM       2
   9 #define CPUID_TLBTYPE   3
  10
  11 #ifdef CONFIG_CPU_CP15
  12 #define read_cpuid(reg)                                                 \
  13         ({                                                              \
  14                 unsigned int __val;                                     \
  15                 asm("mrc        p15, 0, %0, c0, c0, " __stringify(reg)  \
  16                     : "=r" (__val)                                      \
  17                     :                                                   \
  18                     : "cc");                                            \
  19                 __val;                                                  \
  20         })
  21 #else
  22 extern unsigned int processor_id;
  23 #define read_cpuid(reg) (processor_id)
  24 #endif
  25
  26 /*
  27  * The CPU ID never changes at run time, so we might as well tell the
  28  * compiler that it's constant.  Use this function to read the CPU ID
  29  * rather than directly reading processor_id or read_cpuid() directly.
  30  */
  31 static inline unsigned int __attribute_const__ read_cpuid_id(void)
  32 {
  33         return read_cpuid(CPUID_ID);
  34 }
  35
  36 static inline unsigned int __attribute_const__ read_cpuid_cachetype(void)
  37 {
  38         return read_cpuid(CPUID_CACHETYPE);
  39 }
  40
  41 /*
  42  * Intel's XScale3 core supports some v6 features (supersections, L2)
  43  * but advertises itself as v5 as it does not support the v6 ISA.  For
  44  * this reason, we need a way to explicitly test for this type of CPU.
  45  */
  46 #ifndef CONFIG_CPU_XSC3
  47 #define cpu_is_xsc3()   0
  48 #else
  49 static inline int cpu_is_xsc3(void)
  50 {
  51         if ((read_cpuid_id() & 0xffffe000) == 0x69056000)
  52                 return 1;
  53
  54         return 0;
  55 }
  56 #endif
  57
  58 #if !defined(CONFIG_CPU_XSCALE) && !defined(CONFIG_CPU_XSC3)
  59 #define cpu_is_xscale() 0
  60 #else
  61 #define cpu_is_xscale() 1
  62 #endif
  63
  64 #endif