1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Module interface for CPU features 4 * 5 * Copyright IBM Corp. 2015 6 * Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com> 7 */ 8 9 #ifndef __ASM_S390_CPUFEATURE_H 10 #define __ASM_S390_CPUFEATURE_H 11 12 #include <asm/elf.h> 13 14 /* Hardware features on Linux on z Systems are indicated by facility bits that 15 * are mapped to the so-called machine flags. Particular machine flags are 16 * then used to define ELF hardware capabilities; most notably hardware flags 17 * that are essential for user space / glibc. 18 * 19 * Restrict the set of exposed CPU features to ELF hardware capabilities for 20 * now. Additional machine flags can be indicated by values larger than 21 * MAX_ELF_HWCAP_FEATURES. 22 */ 23 #define MAX_ELF_HWCAP_FEATURES (8 * sizeof(elf_hwcap)) 24 #define MAX_CPU_FEATURES MAX_ELF_HWCAP_FEATURES 25 26 #define cpu_feature(feat) ilog2(HWCAP_S390_ ## feat) 27 28 int cpu_have_feature(unsigned int nr); 29 30 #endif /* __ASM_S390_CPUFEATURE_H */ 31