Use the inline function instead of directly indexing the array. This allows some architectures with hardware instructions for bit reversals to eliminate the array. Signed-off-by: Joe Perches <joe@xxxxxxxxxxx> --- On Sun, 2014-10-26 at 23:46 -0700, Joe Perches 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. [] > > diff --git a/include/linux/bitrev.h b/include/linux/bitrev.h > > index 7ffe03f..ef5b2bb 100644 > > --- a/include/linux/bitrev.h > > +++ b/include/linux/bitrev.h > > @@ -3,6 +3,14 @@ > > > > #include <linux/types.h> > > > > +#ifdef CONFIG_HAVE_ARCH_BITREVERSE > > +#include <asm/bitrev.h> > > + > > +#define bitrev32 __arch_bitrev32 > > +#define bitrev16 __arch_bitrev16 > > +#define bitrev8 __arch_bitrev8 > > + > > +#else > > extern u8 const byte_rev_table[256]; drivers/net/wireless/ath/carl9170/phy.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/ath/carl9170/phy.c b/drivers/net/wireless/ath/carl9170/phy.c index b80b213..dca6df1 100644 --- a/drivers/net/wireless/ath/carl9170/phy.c +++ b/drivers/net/wireless/ath/carl9170/phy.c @@ -994,7 +994,7 @@ static int carl9170_init_rf_bank4_pwr(struct ar9170 *ar, bool band5ghz, refsel0 = 0; refsel1 = 1; } - chansel = byte_rev_table[chansel]; + chansel = bitrev8(chansel); } else { if (freq == 2484) { chansel = 10 + (freq - 2274) / 5; @@ -1002,7 +1002,7 @@ static int carl9170_init_rf_bank4_pwr(struct ar9170 *ar, bool band5ghz, } else chansel = 16 + (freq - 2272) / 5; chansel *= 4; - chansel = byte_rev_table[chansel]; + chansel = bitrev8(chansel); } d1 = chansel; -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>