Scott,
On Wed, Nov 13, 2013 at 07:31:02PM -0600, Scott Wood wrote:
On Mon, Aug 26, 2013 at 02:10:56PM +0200, Phil Sutter wrote:
From: Nico Erfurth ne@erfurth.eu
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 ne@erfurth.eu Tested-by: Phil Sutter phil.sutter@viprinet.com Cc: Prafulla Wadaskar prafulla@marvell.com
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.
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.
What target did you use to test this?
I tested using a custom board with Marvell Kirkwood SoC, but e.g. the Marvell OpenRD Ultimate should be fine.
Best wishes,
Phil Sutter Software Engineer