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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-12-15 14:52:16 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-12-15 14:52:16 -0300
commit8d91c1e411f55d7ea91b1183a2e9f8088fb4d5be (patch)
treee9891aa6c295060d065adffd610c4f49ecf884f3 /arch/s390/include/asm/cpufeature.h
parenta71852147516bc1cb5b0b3cbd13639bfd4022dc8 (diff)
Linux-libre 4.3.2-gnu
Diffstat (limited to 'arch/s390/include/asm/cpufeature.h')
-rw-r--r--arch/s390/include/asm/cpufeature.h29
1 files changed, 29 insertions, 0 deletions
diff --git a/arch/s390/include/asm/cpufeature.h b/arch/s390/include/asm/cpufeature.h
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+++ b/arch/s390/include/asm/cpufeature.h
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+/*
+ * Module interface for CPU features
+ *
+ * Copyright IBM Corp. 2015
+ * Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
+ */
+
+#ifndef __ASM_S390_CPUFEATURE_H
+#define __ASM_S390_CPUFEATURE_H
+
+#include <asm/elf.h>
+
+/* Hardware features on Linux on z Systems are indicated by facility bits that
+ * are mapped to the so-called machine flags. Particular machine flags are
+ * then used to define ELF hardware capabilities; most notably hardware flags
+ * that are essential for user space / glibc.
+ *
+ * Restrict the set of exposed CPU features to ELF hardware capabilities for
+ * now. Additional machine flags can be indicated by values larger than
+ * MAX_ELF_HWCAP_FEATURES.
+ */
+#define MAX_ELF_HWCAP_FEATURES (8 * sizeof(elf_hwcap))
+#define MAX_CPU_FEATURES MAX_ELF_HWCAP_FEATURES
+
+#define cpu_feature(feat) ilog2(HWCAP_S390_ ## feat)
+
+int cpu_have_feature(unsigned int nr);
+
+#endif /* __ASM_S390_CPUFEATURE_H */