From: Joe Perches Subject: [PATCH] 6fire: Convert byte_rev_table uses to bitrev8 Date: Tue, 28 Oct 2014 14:22:49 -0700 Message-ID: <1414531369.10912.14.camel@perches.com> References: <35FD53F367049845BC99AC72306C23D103E010D18254@CNBJMBX05.corpusers.net> <35FD53F367049845BC99AC72306C23D103E010D18257@CNBJMBX05.corpusers.net> <1414392371.8884.2.camel@perches.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1414392371.8884.2.camel@perches.com> Sender: owner-linux-mm@kvack.org To: Jaroslav Kysela , Takashi Iwai Cc: "Wang, Yalin" , Russell King , linux-mm@kvack.org, Will Deacon , Akinobu Mita , linux-arm-kernel@lists.infradead.org, alsa-devel , LKML linux-mm@kvack.orgWill Deacon Akinobu Mita linux-arm-kernel@lists.infradead.orgalsa-devel LKML List-Id: alsa-devel@alsa-project.org 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 --- 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 > > > > +#ifdef CONFIG_HAVE_ARCH_BITREVERSE > > +#include > > + > > +#define bitrev32 __arch_bitrev32 > > +#define bitrev16 __arch_bitrev16 > > +#define bitrev8 __arch_bitrev8 > > + > > +#else > > extern u8 const byte_rev_table[256]; sound/usb/6fire/firmware.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sound/usb/6fire/firmware.c b/sound/usb/6fire/firmware.c index 3b02e54..62c25e7 100644 --- a/sound/usb/6fire/firmware.c +++ b/sound/usb/6fire/firmware.c @@ -316,7 +316,7 @@ static int usb6fire_fw_fpga_upload( while (c != end) { for (i = 0; c != end && i < FPGA_BUFSIZE; i++, c++) - buffer[i] = byte_rev_table[(u8) *c]; + buffer[i] = bitrev8((u8)*c); ret = usb6fire_fw_fpga_write(device, buffer, i); if (ret < 0) { -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org