arch/powerpc/include/asm/cpu_has_feature.h

   1 #ifndef __ASM_POWERPC_CPUFEATURES_H
   2 #define __ASM_POWERPC_CPUFEATURES_H
   3
   4 #ifndef __ASSEMBLY__
   5
   6 #include <linux/bug.h>
   7 #include <asm/cputable.h>
   8
   9 static inline bool early_cpu_has_feature(unsigned long feature)
  10 {
  11         return !!((CPU_FTRS_ALWAYS & feature) ||
  12                   (CPU_FTRS_POSSIBLE & cur_cpu_spec->cpu_features & feature));
  13 }
  14
  15 #ifdef CONFIG_JUMP_LABEL_FEATURE_CHECKS
  16 #include <linux/jump_label.h>
  17
  18 #define NUM_CPU_FTR_KEYS        64
  19
  20 extern struct static_key_true cpu_feature_keys[NUM_CPU_FTR_KEYS];
  21
  22 static __always_inline bool cpu_has_feature(unsigned long feature)
  23 {
  24         int i;
  25
  26         BUILD_BUG_ON(!__builtin_constant_p(feature));
  27
  28         if (CPU_FTRS_ALWAYS & feature)
  29                 return true;
  30
  31         if (!(CPU_FTRS_POSSIBLE & feature))
  32                 return false;
  33
  34         i = __builtin_ctzl(feature);
  35         return static_branch_likely(&cpu_feature_keys[i]);
  36 }
  37 #else
  38 static inline bool cpu_has_feature(unsigned long feature)
  39 {
  40         return early_cpu_has_feature(feature);
  41 }
  42 #endif
  43
  44 #endif /* __ASSEMBLY__ */
  45 #endif /* __ASM_POWERPC_CPUFEATURE_H */