lkml.org 
[lkml]   [2014]   [Oct]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Subject[PATCH] carl9170: Convert byte_rev_table uses to bitrev8
From
Date
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@perches.com>
---
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;



\
 
 \ /
  Last update: 2014-10-28 22:21    [W:0.181 / U:0.716 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site