[RFC V2] arm/arm64:add CONFIG_HAVE_ARCH_BITREVERSE to support rbit instruction

[Rob Herring]

On Mon, Oct 27, 2014 at 2:46 PM, Joe Perches <joe at perches.com> wrote:
> On Mon, 2014-10-27 at 14:37 +0800, Wang, Yalin wrote:
>> this change add CONFIG_HAVE_ARCH_BITREVERSE config option,
>> so that we can use arm/arm64 rbit instruction to do bitrev operation
>> by hardware.

I don't see the original patch in my inbox, so replying here.

>>
>> Signed-off-by: Yalin Wang <yalin.wang at sonymobile.com>
>> ---
>>  arch/arm/Kconfig                |  1 +
>>  arch/arm/include/asm/bitrev.h   | 21 +++++++++++++++++++++
>>  arch/arm64/Kconfig              |  1 +
>>  arch/arm64/include/asm/bitrev.h | 21 +++++++++++++++++++++
>>  include/linux/bitrev.h          |  9 +++++++++
>>  lib/Kconfig                     |  9 +++++++++
>>  lib/bitrev.c                    |  2 ++
>>  7 files changed, 64 insertions(+)
>>  create mode 100644 arch/arm/include/asm/bitrev.h
>>  create mode 100644 arch/arm64/include/asm/bitrev.h
>>
>> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
>> index 89c4b5c..426cbcc 100644
>> --- a/arch/arm/Kconfig
>> +++ b/arch/arm/Kconfig
>> @@ -16,6 +16,7 @@ config ARM
>>       select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS
>>       select GENERIC_ALLOCATOR
>>       select GENERIC_ATOMIC64 if (CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI)
>> +     select HAVE_ARCH_BITREVERSE if (CPU_V7M || CPU_V7)
>>       select GENERIC_CLOCKEVENTS_BROADCAST if SMP
>>       select GENERIC_IDLE_POLL_SETUP
>>       select GENERIC_IRQ_PROBE

[...]

>> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
>> index 9532f8d..263c28c 100644
>> --- a/arch/arm64/Kconfig
>> +++ b/arch/arm64/Kconfig
>> @@ -36,6 +36,7 @@ config ARM64
>>       select HARDIRQS_SW_RESEND
>>       select HAVE_ARCH_AUDITSYSCALL
>>       select HAVE_ARCH_JUMP_LABEL
>> +     select HAVE_ARCH_BITREVERSE
>>       select HAVE_ARCH_KGDB
>>       select HAVE_ARCH_TRACEHOOK
>>       select HAVE_BPF_JIT

The kconfig lists should be sorted.

Rob