Hi, balbi On Tue, Jun 14, 2011 at 5:57 PM, Felipe Balbi <balbi@xxxxxx> wrote: > Hi, > > On Tue, Jun 14, 2011 at 05:52:23PM +0800, Aaron Wu wrote: >> On Tue, Jun 14, 2011 at 5:39 PM, Felipe Balbi <balbi@xxxxxx> wrote: >> > Hi, >> > >> > On Tue, Jun 14, 2011 at 05:34:09PM +0800, Aaron Wu wrote: >> >> Since the wifi card we are using is of the USB interface. We tried on >> >> two diffrent USB controllers, looks like the ISP1362 works OK and >> >> problems happens only on MUSB controller. For both USB controllers we >> >> are using the same kernel version and USB wifi card. >> > >> > Yeah, USB host has quite some performance issues to be fixed. To start >> > with, it uses only DMA Mode0, which is bound to packet boundaries. BTW, >> > which embedded platform are you using ? Which SoC ? >> > >> >> Hi balbi, >> Thanks for the quick reply. Our concern is the priority capability, >> current problems is, the network data packge should have been >> prioritized in the IPV4 stack itself, by IP_TOS option as mentioned, >> we are just curious why the priority looks like to have something to >> do with the USB controller, I mean by experiment the prioritization >> works well on some USB controllers like that on a X86 PC and ISP1362, >> but does not work on MUSB. >> >> We are using PIO mode on Blackfin. Performance is not our concern at >> this moment, actually the MUSB has better throughput performance than >> the ISP1362, but the prioritization works on 1362. On the 1362 >> controller, the second iperf session(high priority) always take up a >> large bandwidth while the other two low priority session get only a >> little in the test as expected. On MUSB, we see no priority for the >> second session, it drops greatly as if it has the same low priority as >> the first and third session. > > Well, I can't answer that question, specially since it's on Blackfin. > > Maybe Mike can help I have looked into that problem and have no idea. So i asked Aaron to email to maillist for some help. Is anyone can help verify this problem on other musb platform? Thanks. -- Regards, --Bob -- 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
