> The driver development is stalled and I don't know when I'll be able to > continue working on it.
Bad news, but I do understand. Please inform me when you will resume working on the driver, so that I can inform you of the progress I will have made (if any). > >What are the major performance issues ? > > One of the issues in this driver is redunduncy between qe end ep > structures and as a consequence a lot of uneeded code that make cross > updates. > I didn't run profiling, so I can't tell better. Ok. > >I noticed that the driver uses the MPC82xx packet level interface. > >Why don't you use the transaction level interface ? > > The original driver I've started with used packet level. I thought on > switching to transaction level, but I hadn't time for it because of > other projects pressure. Do you think it would be worth it, or are there any issue which you are aware of that would make it difficult/impractical/impossible/useless ? > >That might explain why some devices don't even respond to the first > > request. I noticed that, on my EP8248 board, the controller only sends > > 990 SOF packets per second (or rather 990 SOF interrupts are generated). > > I might have a time base problem somewhere, as I computed the number of > > interrupts per second with a simple > > > >cat /proc/driver/m8xxhci_privateh > sof.1 && sleep 300 && > >cat /proc/driver/m8xxhci_privateh > sof.2 > > I'm not sure such measurements are correct, since you sleep not exatly > 300 seconds. I haven't measured how many SOF interrupts I get, but I > think you maybe right. > It may happen that during transmit or recieve the interrupts are off and > SOF packets are not sent. My bad, this was caused by the boot loader passing 66000000Hz instead of 66666666Hz to Linux as the bus frequency. This is fixed now, and I get 1000 SOF interrupts per second. > >Do you have the same problem ? I'll see if I can get my hands on a USB > >protocol analyzer. > > Good luck, I'll try to help but unfotunately I'm very much busy with > other projects now. Thanks for your help already. Laurent Pinchart
