Hi Daniel, >From: Daniel Mack [mailto:zon...@gmail.com] > >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 _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot