Re: Unable to randomly boot rootfs (EXT3 or EXT4) from SD: MMC error -110 (TIMEDOUT)

[Theodore Ts'o <tytso@mit.edu>]

On Wed, Aug 28, 2013 at 11:22:58AM -0400, Kevyn-Alexandre Paré wrote:
> We try multiple of our system ( Different micro SD from SanDisk +
> Overo with OMAP3) and they are all doing this with the SanDisk 64GB,
> 32GB :
> http://www.sandisk.com/products/memory-cards/microsd/ultra-class10-for-android/?capacity=64GB
> 
> The problem seem to be easier to reproduce when we just flash the
> micro SD (partition, format & copy rootfs) at it first boot.
> Also, when we let the system down for a couple of days and then
> sometimes we need to reboot the system multiple times before it fall
> back alright.
> 
> We found a old patch that was simply increasing the timeout of the host:
> http://cgit.openembedded.org/cgit.cgi/openembedded/tree/recipes/linux/linux-omap-2.6.39/sakoman/0024-omap-mmc-Adjust-dto-to-eliminate-timeout-errors.patch?h=org.openembedded.dev
> 
> By settings the timeout to zero I reproduce kind of the same timeout
> error at every boot. That was expected since I don't let enough time
> to the controller to respond...
> 
> Could the mix of that MMC controller and these card is not optimal? Is
> the driver fully supporting the UHS-I speed grade?

I've cc'ed Arnd Bergman who works at Linaro; I suspect that if he
doesn't know the answer off the top of his head, he can probably
direct you to someone who will.

							- Ted