> -----Original Message----- > From: linux-omap-ow...@vger.kernel.org [mailto:linux-omap- > ow...@vger.kernel.org] On Behalf Of Gadiyar, Anand > Sent: Friday, May 28, 2010 2:55 PM > To: Stephen Schwarm, CSDP; linux-omap@vger.kernel.org > Subject: RE: simple sd card performance bug fix on OMAP > > Stephen Schwarm, CSDP wrote: > > > > I have not had time to make a formal patch for this but I thought it was > > significant enough just to send it out. The problem is on omap systems > > that use omap_hsmmc.c to run sd or mmc cards. If the system you are > > using has an 8 wire interface, it will only use a one wire interface to > > 4 wire cards (eg, sd class 4 and sd class 6). > > > > In the file driver/mmc/omap_hsmmc.c in the function omap_hsmmc_probe: > > at about line 1739 change: > > > > if (mmc_slot(host).wires >= 8) > > mmc->caps |= MMC_CAP_8_BIT_DATA; > > else if (mmc_slot(host).wires >= 4) > > mmc->caps |= MMC_CAP_4_BIT_DATA; > > > > to: > > > > if (mmc_slot(host).wires >= 8) > > mmc->caps |= MMC_CAP_8_BIT_DATA; > > if (mmc_slot(host).wires >= 4) > > mmc->caps |= w; > > > > just delete the word "else". This sets the MMC_CAP_4_BIT_DATA bit on > > interfaces that have 8 wire interfaces. > > > > We have seen a BIG performance improvement on our systems. > > > > Thanks for reporting this. > > A similar patch was posted a while ago and is currently marked as > "awaiting upstream", although it looks like it got lost again. > > <https://patchwork.kernel.org/patch/78713/> > A revised version of the same patch was posted.
https://patchwork.kernel.org/patch/93519/ Tony, Can you please push this? Regards, Madhu > - Anand > -- > To unsubscribe from this list: send the line "unsubscribe linux-omap" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
