ARM: elf: add new hwcap for identifying atomic ldrd/strd instructions
authorWill Deacon <will.deacon@arm.com>
Mon, 8 Apr 2013 16:13:12 +0000 (17:13 +0100)
committerWill Deacon <will.deacon@arm.com>
Thu, 30 May 2013 15:02:34 +0000 (16:02 +0100)
commita469abd0f868c902b75532579bf87553dcf1b360
tree45b8497556dff1a90311bbd087f34ff4791be9d6
parente38a517578d6c0f764b0d0f6e26dcdf9f70c69d7
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>
arch/arm/include/uapi/asm/hwcap.h
arch/arm/kernel/setup.c