LXR linux/arch/s390/include/asm/cpufeature.h

   1/*
   2 * Module interface for CPU features
   3 *
   4 * Copyright IBM Corp. 2015
   5 * Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
   6 */
   7
   8#ifndef __ASM_S390_CPUFEATURE_H
   9#define __ASM_S390_CPUFEATURE_H
  10
  11#include <asm/elf.h>
  12
  13/* Hardware features on Linux on z Systems are indicated by facility bits that
  14 * are mapped to the so-called machine flags.  Particular machine flags are
  15 * then used to define ELF hardware capabilities; most notably hardware flags
  16 * that are essential for user space / glibc.
  17 *
  18 * Restrict the set of exposed CPU features to ELF hardware capabilities for
  19 * now.  Additional machine flags can be indicated by values larger than
  20 * MAX_ELF_HWCAP_FEATURES.
  21 */
  22#define MAX_ELF_HWCAP_FEATURES  (8 * sizeof(elf_hwcap))
  23#define MAX_CPU_FEATURES        MAX_ELF_HWCAP_FEATURES
  24
  25#define cpu_feature(feat)       ilog2(HWCAP_S390_ ## feat)
  26
  27int cpu_have_feature(unsigned int nr);
  28
  29#endif /* __ASM_S390_CPUFEATURE_H */
  30