Madhusudhan <madhu.cr@xxxxxx> wrote: >> -----Original Message----- >> From: linux-mmc-owner@xxxxxxxxxxxxxxx [mailto:linux-mmc- >> owner@xxxxxxxxxxxxxxx] On Behalf Of Venkatraman S >> Sent: Monday, March 01, 2010 5:27 AM >> To: linux-mmc@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; >> linux-omap@xxxxxxxxxxxxxxx >> Subject: [PATCH 03/03] omap hsmmc: adaptation of sdma descriptor >> autoloading feature >> >> Start to use the sDMA descriptor autoloading feature. >> For large datablocks, the MMC driver has to repeatedly setup, program >> and teardown the >> dma channel for each element of the sglist received in omap_hsmmc_request. >> >> By using descriptor autoloading, transfers from / to each element of >> the sglist is pre programmed >> into a linked list. The sDMA driver completes the entire transaction >> and provides a single interrupt. >> >> Due to this, number of dma interrupts for a typical 100MB transfer on the >> MMC is >> reduced from 25000 to about 400 (approximate). Transfer speeds are >> improved by ~5% >> (Though it varies on the size of read / write & improves on huge >> transfers) >> >> Descriptor autoloading is available only in 3630 and 4430 (as of now). >> Hence normal DMA >> mode is also retained. >> >> Tested on omap4430 sdp. >> >> Signed-off-by: Venkatraman S <svenkatr@xxxxxx> > > I don't see any issues with this patch except the concern I had on the first > patch in the series. Why is that change linked to this series? > Thanks. The problem was seen only in the context of using descriptor load. Would you prefer that I post it as a separate patch ? Regards, Venkat. -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
