> -----Original Message----- > From: [email protected] [mailto:linux-omap- > [email protected]] On Behalf Of Stephen Schwarm, CSDP > Sent: Friday, May 28, 2010 2:05 PM > To: [email protected] > Subject: simple sd card performance bug fix on OMAP > > 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). > A patch to fix this was already posted on LO by Kishore.
Regards, Madhu > 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. > > Steve Schwarm > -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
