On Wednesday 27 January 2010 00:13:48 Robert Nelson wrote: > On Tue, Jan 26, 2010 at 4:30 PM, Andreas Hartmetz <ahartmetz@xxxxxxxxx> wrote: > > Hi, > > > > I have a problem with the USB OTG port on my Beagle Board revision B6 - > > the OTG port is the only USB port on that device so it's critical that > > it works. Everybody on this list probably knows this hardware, I'll just > > say that it has an ARM Cortex-A8 CPU (OMAP3530) with a built-in USB > > interface. The driver is musb_hdrc. > > I'm using this interface in host mode (no gadget mode support compiled > > in, though this doesn't seem to make a difference) to attach necessary > > peripherals via a powered USB hub. The make and model of hub do not play > > a role, I've tried several. > > > > The problem: > > Whenever the following conditions are met all hardware on the port > > "disappears" after a few minutes, cutting off the board from network and > > storage: - Network traffic over USB (doesn't matter if it's regular 100 > > Mbps Ethernet or a WLAN stick) > > - Disk "traffic" over USB - I use a 2,5" disk in a USB enclosure > > - CPU load - not sure if this is necessary > > The only fix seems to be a reboot. > > > > This happens to me when compiling something on the board (easier than > > cross-compiling) with the help of Icecream, which is a kind of distcc on > > steroids. On #beagle on Freenode IRC I've found somebody with the same > > problem when scp-ing a large file (several hundred megabytes) off or > > onto the USB disk. I can reproduce that as well. > > I have spent a lot of time trying to find fixes and/or workarounds but > > nothing worked so far except using the "validation kernel" recommended > > to test the hardware e.g. after receipt: > > http://code.google.com/p/beagleboard/wiki/BeagleBoardDiagnostics. > > Fittingly, the link to the kernel image is currently broken. The board > > usually locked itself up after about a day when using that ancient > > kernel, so it's not an option either, and probably quite unmaintained > > and buggy in many other areas. > > > > So far I have tried many versions of the linux-omap and linux-omap-pm > > kernel, from about 2.6.30 to the latest git version. They all exhibit > > the USB OTG death bug. > > I've used kernels with openembedded patches and without, currently > > without. Yesterday I discovered the musb_hdrc.fifo_mode parameter and > > played around with it. I also modified the given configurations. Result: > > - FIFO configurations including .mode = BUF_DOUBLE don't work at all - no > > devices work. > > - the USB death bug is not fixed by: > > - using only one endpoint > > - using no TXRX entries but only separate RX and TX > > (every endpoint gets a TX and an RX entry though) > > - using a large number of endpoints with same maxpacket value > > ... still no solution. > > > > Enabling debug output of the musb_hdrc driver (yes I've also compiled in > > debug messages) is not very practical due to the high volume of > > messages; also, when the bug occurs nothing special is printed. The > > first error usually comes from the memory manager / filesystem > > complaining that it can't do "IO to offline device", i.e. the > > disappeared external harddisk (which contains the swapfile). > > > > I would *really* appreciate somebody looking into this because this > > currently makes the hardware as useful as a brick for me. I can supply > > debug output and test patches. > > > > Cheers, > > Andreas > > Hi Andreas, > > Give this patch a try: > http://bazaar.launchpad.net/~beagleboard-kernel/%2Bjunk/2.6-stable/annotate > /head%3A/patches/musb/fifo-change.patch > > It's in Angstrom's 2.6.29, my 2.6.31/32... And a real fix just went > into mainline 2.6.33-rc5, with it my otg port is solid as a rock and > can transfer large amounts of data between shared devices on the > otg/musb port... > > http://rcn-ee.homeip.net:81/dl/farm/log/2.6.32.6-x6.0_beagle-128mb-0_musb-s > tress-test.txt > > Regards, Nice try, but no success. I've tried the fifo-change patch against the pm branch (with musb_hdrc.fifo_mode=4 obviously, otherwise it wouldn't do anything) and also the 2.6.32.6-x6.0 kernel from you. Nothing is fixed for me. With your kernel I have an additional problem I don't have with pm: it takes several tries to bring up the USB WLAN interface to a working state, with the rt73usb driver. Basically I start and kill wpa_supplicant, unload the module a few times and whatnot until it works. DHCP seems to work almost every time but no IP or ICMP packets come through. I know it sounds strange. When it works ping response times range from one to ten seconds (?!) whereas they are in the several milliseconds range with pm. I tried your latest kernel with and without musb_hdrc.fifo_mode=4 to be sure. Which fix in mainline do you mean btw? As long as no particular commit fixes the bug I consider it fixed by accident, and it may break again by accident. I suspect that your stress test is not stressful enough. Try scp or anything that loads the CPU heavily while network and disk I/O is going on. Maybe throw in some swapping with swap on the external disk for good measure, git gc seems to work well for that. If all else fails I can publish a filesystem image with a distributed build ready to run. Andreas -- 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
