Hello, Oleksandr and myself have been looking into why when we enable the write-back cache on the PandaBoard there are kernel panics with USB. We have tracked it down to an issue appending the ehci_qh_t to the list at the end of ehci_setup_standard_chain().
I have a patch at [1] that allows me to run sha256 on a 40MB file over NSF using the built in smsc USB ethernet chip. The problem is I have had to place a call to DELAY before EHCI_APPEND_QH. This is obviously not the correct solution. Is anyone able to help me narrow down what is missing? It appears to be a missing cache invalidate or flush somewhere but I haven't been able to track down what cache function the DELAY is working around. Andrew [1] http://fubar.geek.nz/files/freebsd/ehci_4.diff _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-usb To unsubscribe, send any mail to "[email protected]"
