ARM: elf: add new hwcap for identifying atomic ldrd/strd instructions

CPUs implementing LPAE have atomic ldrd/strd instructions, meaning that
userspace software can avoid having to use the exclusive variants of
these instructions if they wish.

This patch advertises the atomicity of these instructions via the
hwcaps, so userspace can detect this CPU feature.

Reported-by: Vladimir Danushevsky <vladimir.danushevsky@oracle.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This commit is contained in:
Will Deacon
2013-04-08 17:13:12 +01:00
parent e38a517578
commit a469abd0f8
2 changed files with 8 additions and 2 deletions

View File

@@ -25,6 +25,6 @@
#define HWCAP_IDIVT (1 << 18)
#define HWCAP_VFPD32 (1 << 19) /* set if VFP has 32 regs (not 16) */
#define HWCAP_IDIV (HWCAP_IDIVA | HWCAP_IDIVT)
#define HWCAP_LPAE (1 << 20)
#endif /* _UAPI__ASMARM_HWCAP_H */