Hi Daniel, >From: Gupta, Pekon > >Hi Daniel, > >>From: Daniel Mack [mailto:[email protected]] >> >>Resending this since I got no replies on the first version. >>I also fixed up the commit log of #1. >> >I plan to test this, but there is still a long pending list of patches which >for me to test in kernel and u-boot. So it might take bit time. >But really thanks much for this feature addition. > >Just a minor feedback, if you like it... >GPMC controller support various transfer modes >- POLLED: <default mode> >- PREFETCH_POLLED : <as added in this patch> >- PREFETCH_IRQ: <not implemented/required> >- PREFETCH_DMA: <not implemented/required> > >(1) Will it be okay to use following config names, this would be synonymous >to the xfer-modes DT binding used in kernel ? >CONFIG_NAND_OMAP_XFER_MODE_POLLED >CONFIG_NAND_OMAP_XFER_MODE_PREFETCH_POLLED > >(2) It would be good if you can make "PREFETCH_POLLED" mode as "default" >And instead make "POLLED" mode selectable. >#ifdef CONFIG_NAND_OMAP_XFER_MODE_POLLED > /* old behavior */ >#else /* > /* default PREFETCH_POLLED mode */ >#endif > >However, let me first test your patch, and these minor nit-picks >(if required) can be done later. > >Thanks.. >with regards, pekon >>------------ >> >>I spent some time looking into boot times of AM335x platforms. One big >>improvement I made came with adding support for GPMC prefetch mode, >>which gave a speed-up of NAND reads of roughly factor 2. >>This is what patch #1 does. >> >>Note that this is currently limited to read operations in 8-bit mode, but >>I believe it could be easily extended to 16-bit operations if anyone has >>hardware to test it on. Using the engine for write mode speed >>improvements should also be doable, but I didn't spend time on it yet. >>That can be added as a separate patch later. >> >>Patch #2 decreases the GPMC memory map window size from 256MiB to 16MiB. >>Admittedly, I'm not quite sure about the reason, but a read from >>offset 0 in this memory area will freeze U-Boot instantly if the size >>is configured to 256MiB. As contents of the FIFO are accessed in a >>pseudo-mode from offset 0 anyway, it doesn't really matter. >> >>What I also did to further speed up my boot was to tweak the GPMC >>parameters for the NAND chip on our boards, but that's not part of this >>patch set, and probably deserves a little more cleanup. >> >>Test results and feedback very welcome. >> >>Thanks, >>Daniel >> >> >>Daniel Mack (2): >> mtd: OMAP: Enable GPMC prefetch mode >> ARM: omap-common: gpmp: decrease memory region size to 16MiB >> >> arch/arm/cpu/armv7/omap-common/mem-common.c | 2 +- >> doc/README.nand | 5 ++ >> drivers/mtd/nand/omap_gpmc.c | 115 >> +++++++++++++++++++++++++++- >> include/linux/mtd/omap_gpmc.h | 6 +- >> 4 files changed, 124 insertions(+), 4 deletions(-) >> >>-- >>1.9.3
My apologies, sorry I'm unable to test this patch-set. But as I have already reviewed it. And apart from minor comments for rest of things Reviewed-by: Pekon Gupta <[email protected]> with regards, pekon _______________________________________________ U-Boot mailing list [email protected] http://lists.denx.de/mailman/listinfo/u-boot
