>-----Original Message----- >From: Gadiyar, Anand [mailto:gadiyar@xxxxxx] >Sent: Friday, April 02, 2010 11:35 PM >To: felipe.balbi@xxxxxxxxx; Subbrathnam, Swaminathan >Cc: Mike Frysinger; linux-usb@xxxxxxxxxxxxxxx; >uclinux-dist-devel@xxxxxxxxxxxxxxxxxxxx; Greg Kroah-Hartman; Cai, Cliff >Subject: RE: [PATCH 2/2 v2] USB: musb: disable double >buffering for older RTL versions > >Felipe Balbi wrote: >> Subbrathnam, Swaminathan wrote: >> > This issue is specific to Blackfin architecture. >Platforms like >> > DaVinci, OMAP etc. do not have this restriction or have not >> > observed any hangs in double buffering mode. >> > >> > I do not see the change implemented specific Blackfin context. >> > Pl. modify the patch accordingly. >> >> NAK. I have observed data corruption when using double buffering on >> tusb6010, omap3430 and omap3630. >> > >Sorry, I did not catch this earlier before this patch was merged. > >Bringing this issue back up, do you have details on the data >corruption seen? Did you have both TX and RC double-buffering >enabled, or only one at a time? It can't pass some basic gadget test,i.e. gadget ethernet When running "ping -c 1 -s somesize ipaddress" it will print Out the data corruption. It seems to affect both sides, >It could be that only one direction is problematic and this >patch prevents us from even attempting double-buffering on the >other direction. >tusb6010 and the OMAPs have dynamic fifo, so the problem can >be taken care of simply by choosing the correct fifo table. >Default tables don't use double buffering, so they should not >be affected. So,does this patch affect above parts? >In blackfin's case, maybe it makes more sense to use the newly >register bits that explicitly disable double buffering. I >believe these were added specifically to take care of the >scenario blackfin faces - not having dynamic fifo. I'm afraid the old revision musb doesn't have such bits. >Would anyone with a blackfin system care to test such a patch? >I can post it in a bit. Yes, this patch is based on the test on blackfin. Thanks Cliff -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
