> -----Original Message----- > From: kishore kadiyala [mailto:kishorek.kadiyala@xxxxxxxxx] > Sent: Wednesday, March 31, 2010 2:03 AM > To: Vimal Singh > Cc: Madhusudhan; tony@xxxxxxxxxxx; svenkatr@xxxxxx; linux- > omap@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; > jarkko.lavinen@xxxxxxxxx > Subject: Re: [PATCH-V2] OMAP: Fix for bus width which improves SD card's > peformance. > > Sorry for that and here's the Updated one. > > From: Kishore Kadiyala <kishore.kadiyala@xxxxxx> > > This patch improves low speeds for SD cards. > OMAP-MMC controller's can support maximum bus width of '8'. > when bus width is mentioned as "8" in controller data,the SD > stack will check whether bus width is "4" and if not it will > set bus width to "1" and there by degrading performance. > This patch fixes the issue and improves the performance of > SD cards. > > Signed-off-by: Kishore Kadiyala <kishore.kadiyala@xxxxxx> > Signed-off-by: Venkatraman S <svenkatr@xxxxxx> > Acked-by: Madhusudhan Chikkature <madhu.cr@xxxxxx> > > --- > In V2 : Appended Signed-off by Venkat and Ack by Madhu > > Here are my experiment numbers, on a Class 6 SDHC card: > Read peformance is increased by 220% > Write Performance is increased by 52% > > drivers/mmc/host/omap_hsmmc.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c > index 83f0aff..8c97c22 100644 > --- a/drivers/mmc/host/omap_hsmmc.c > +++ b/drivers/mmc/host/omap_hsmmc.c > @@ -2092,7 +2092,7 @@ static int __init omap_hsmmc_probe(struct > MMC_CAP_WAIT_WHILE_BUSY; > > if (mmc_slot(host).wires >= 8) > - mmc->caps |= MMC_CAP_8_BIT_DATA; > + mmc->caps |= (MMC_CAP_8_BIT_DATA | MMC_CAP_4_BIT_DATA); > else if (mmc_slot(host).wires >= 4) > mmc->caps |= MMC_CAP_4_BIT_DATA; > Kishore, Since this patch is not yet pushed it makes sense to fix the readability issue. Since 8-bit is the max how about: if (mmc_slot(host).wires == 8) mmc->caps |= MMC_CAP_8_BIT_DATA | MMC_CAP_4_BIT_DATA; if (mmc_slot(host).wires == 4) mmc->caps |= MMC_CAP_4_BIT_DATA; This would be little easy to read the code. Can you please repost the patch?? Regards, Madhu > -- > 1.6.3.3 -- 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
