From mboxrd@z Thu Jan 1 00:00:00 1970 From: Holger Brunck Date: Thu, 14 Nov 2013 09:18:41 +0100 Subject: [U-Boot] [U-Boot,PATCHv4] Optimized nand_read_buf for kirkwood In-Reply-To: <20131114013102.GA12213@home.buserror.net> References: <1377519056-25364-1-git-send-email-phil.sutter@viprinet.com> <20131114013102.GA12213@home.buserror.net> Message-ID: <52848761.3080004@keymile.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Scott, On 11/14/2013 02:31 AM, Scott Wood wrote: > On Mon, Aug 26, 2013 at 02:10:56PM +0200, Phil Sutter wrote: >> From: Nico Erfurth >> >> The basic idea is taken from the linux-kernel, but further optimized. >> >> First align the buffer to 8 bytes, then use ldrd/strd to read and store >> in 8 byte quantities, then do the final bytes. >> >> Tested using: 'date ; nand read.raw 0xE00000 0x0 0x10000 ; date'. >> Without this patch, NAND read of 132MB took 49s (~2.69MB/s). With this >> patch in place, reading the same amount of data was done in 27s >> (~4.89MB/s). So read performance is increased by ~80%! >> >> Signed-off-by: Nico Erfurth >> Tested-by: Phil Sutter >> Cc: Prafulla Wadaskar >> >> --- >> Changed since V3: >> - fixed author >> --- >> drivers/mtd/nand/kirkwood_nand.c | 32 ++++++++++++++++++++++++++++++++ >> 1 file changed, 32 insertions(+) > > I tried to build-test this, and I couldn't find any board that defines > CONFIG_NAND_KIRKWOOD. > it's not in board specific code defined it's defined in a common kirkwood header: arch/arm/include/asm/arch-kirkwood/config.h:58:#define CONFIG_NAND_KIRKWOOD > The patch that removed it was commit > b5befd8211b54ae2d2fca3fbed061c879951ceaa ("arm/km: fix u-boot.kwb build > breakage"), over two years ago. It's not clear whether the removal was > intentional. > yes it was. We include this common header and therefore we don't need to redefine it in our board setup. Regards Holger