2010/8/27 Gadiyar, Anand <gadi...@ti.com>: > tom.leim...@gmail.com wrote: >> >> From: Ming Lei <tom.leim...@gmail.com> >> >> This patch fixes one bugs of OUT transfer in double buffer case: >> >> -the current code only enable autoclear for dma mode 1, and not >> for dma mode 0 >> >> Without this patch, test #5 of usbtest can't be passed if we >> configure musb as g_zero and use fifo mode 3 to enable double >> buffer mode. >> >> With this patch and the following patch(fix dma length), >> on my beagle B5, test#5(queued bulk out) may go beyond >> 18Mbyte/s(seems dma mode 0 is quicker in double buffer case) >> if musb is configured as g_zero and fifo mode 3 is taken, follows >> the test command: >> >> #./testusb -D DEV_NAME -c 1024 -t 5 -s 32768 -g 8 [1] >> >> Also I have tested this patch can't make g_ether broken. >> >> [1], >> -source of testusb : tools/usb/testusb.c under linux kernel; >> >> Signed-off-by: Ming Lei <tom.leim...@gmail.com> >> Cc: Anand Gadiyar <gadi...@ti.com> >> Cc: Mike Frysinger <vap...@gentoo.org> >> Cc: Sergei Shtylyov <sshtyl...@ru.mvista.com> > > I'm not 100% sure why not having autoclear was causing a failure > with double-buffering enabled. I'd like this patch to be tested > more on OMAP as well as on Blackfin/Davinci.
We don't clear MUSB_RXCSR_RXPKTRDY explicitly when dma complete, so if autoclear is not enabled, the dma read for packets from fifo will not be acked, then any odd things may happen... I have tested the patch for both single buffer and double buffer case, test #5 and test #6 are passed, and result of test #5 in double buffer may go beyond 18M/s(seems much quicker than dma mode 1). Also, g_ether is OK with the patch. > > I'll need time to study MUSB specs again to understand this, > so I'll skip acking this patch and let Felipe/Sergei/Mike/Ajay > take a look. Very good. > > Thanks for taking the time to debug this - if this patch series > makes double buffering work reliably, that's a very good boost > to throughput. > > - Anand > >> --- >> drivers/usb/musb/musb_gadget.c | 2 +- >> 1 files changed, 1 insertions(+), 1 deletions(-) >> >> diff --git a/drivers/usb/musb/musb_gadget.c b/drivers/usb/musb/musb_gadget.c >> index e0bd1c1..c0dfec4 100644 >> --- a/drivers/usb/musb/musb_gadget.c >> +++ b/drivers/usb/musb/musb_gadget.c >> @@ -645,9 +645,9 @@ static void rxstate(struct musb *musb, struct >> musb_request *req) >> */ >> >> csr |= MUSB_RXCSR_DMAENAB; >> -#ifdef USE_MODE1 >> if (!musb_ep->hb_mult) >> csr |= MUSB_RXCSR_AUTOCLEAR; >> +#ifdef USE_MODE1 >> /* csr |= MUSB_RXCSR_DMAMODE; */ >> >> /* this special sequence (enabling and then >> -- >> 1.6.2.5 >> >> -- Lei Ming -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
