Mathieu Poirier <mathieu.poirier@xxxxxxxxxxxxx> wrote: > On Tue, 2010-06-15 at 20:58 +0530, Venkatraman S wrote: >> Mathieu Poirier <mathieu.poirier@xxxxxxxxxxxxx> wrote: >> > HW: Beagleboard rev. C2 and C4 >> > Processor: OMAP3 >> > Kernel: 2.6.35-rc2 >> > Driver: mmci-omap-hs >> > >> > I am faced with an SDHC card problem on a beagleboard. Some cards >> > cannot be initialized on startup while others work perfectly. I tracked >> > the issue down to one single kernel config: PREEMPT_VOLUNTARY. >> > >> > When going from PREEMPT_VOLUNTARY to PREEMPT_NONE the problem goes away. >> > >> > When booting, a failing card (PREEMPT_VOLUNTARY) will output the >> > following: >> > [ 2.283355] mmc0: error -110 whilst initialising SD card >> > >> > I have also seen transfer errors such as this one: >> > [ 105.343780] mmcblk0: error -110 transferring data, sector 798431, nr >> > 26, card status 0xc00 >> > >> > When working properly (PREEMPT_NONE), you get: >> > [ 27.026519] mmc0: new high speed SDHC card at address 0007 >> > [ 27.075775] mmcblk0: mmc0:0007 SD08G 7.49 GiB >> > >> > We seem to have a little timing problem - has anyone seen the same >> > issue ? Can driver "mmci-omap-hs" actually work under >> > PREEMPT_VOLUNTARY ? >> > >> > Thanks, Mathieu. >> > >> >> I will check this out - not tested with PREEMPT_VOLUNTARY so far. >> If it's not too much trouble, can you provide a log with CONFIG_MMC_DEBUG ? >> Also, some details about the failing card would be helpful. >> >> Thanks, >> Venkat. > > Venkat, > > Unfortunately enabling CONFIG_MMC_DEBUG doesn't yield more information - > the error message is the same and no additional output shows on the > console. > > As for the cards, had failures with 3 different manufacturer: > - Patriot Memory, MicroSD card, 8GB, class 4, SDHC. > - Kinston, 4GB, class 6, SDHC. > - Sandisk, 4GB, Class 2, SDHC. > > I am more than willing to test kernels for you if need be. > > Thanks, Mathieu. > For MMC/SD logs to be sent to the console, you need to a) "echo 8 > /proc/sys/kernel/printk" in the shell and b) insert the card If you are booting from the card itself, then this won't work and DEBUG_LL has to be enabled (in addition to CONFIG_MMC_DEBUG) Apologies - I should have explained this initially. 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
