
+Julius, who may have more comment
Hi Marshall,
On Mon, Aug 19, 2013 at 4:41 PM, Marshall Ha marshha@gmail.com wrote:
Hi Simon,
I saw that you had proposed a patch for increasing the U-Boot timeout to work with some USB flash devices:
http://lists.denx.de/pipermail/u-boot/2010-December/083467.html
I have also ran into this problem in U-Boot, with the same root cause. I realize that this mailer is primarily for U-Boot, but I was curious whether this was an issue that you had encountered only in U-Boot, or whether you had also observed this problem after booting into an operating system. For example, I have observed that once booted into Linux, the USB devices will return I/O errors after heavy read/write activity, which I suspect to have the same root cause.
I believe this code was merged into U-Boot - or at least in Chrome OS I'm not aware of any patches to this code that remain (on top of mainline) other than the USB3 work.
Some devices do have strange characteristics, and increasing the timeout can make them work. However, it's tricky since it then makes every other device slower (if we are scanning for something that isn't there and waiting longer than we need to for 99% of the devices out there).
So either you have found a real bug in U-Boot and Linux, or the device is broken. I'm not sure which, but it is worth investigating with an open mind.
Regards, Simon
Thanks, Marshall