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-stress-test.txt Regards, -- Robert Nelson http://www.rcn-ee.com/ -- 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
