On Mon, Aug 4, 2014 at 5:55 PM, Paul Zimmerman <Paul.Zimmerman@xxxxxxxxxxxx> wrote: >> From: Valdis.Kletnieks@xxxxxx [mailto:Valdis.Kletnieks@xxxxxx] >> Sent: Monday, August 04, 2014 1:28 PM >> >> On Mon, 04 Aug 2014 19:40:15 -0000, Paul Zimmerman said: >> >> > Ah, you didn't read far enough down the page :) >> >> I'm willing to bet a large pizza with everything but anchovies that >> out in the real world, a lot of implementors didn't read further either. :) > > Nah, I won't take that bet :) > >> > So I have to believe there are a *lot* of systems out there that do support xHCI debug. >> >> Possibly. But enough to make an actual critical mass to motivate somebody >> to write code? Or do you get more bang-for-buck by fixing kgdb to support >> debugging over Ethernet? > > Well, code to support the xHCI debug capability has been written, see > http://marc.info/?l=linux-usb&m=135948845511047. But I did not get > approval from my management to spend the time needed to integrate this > into the kernel's kgdb support. > > Nick, if you are still interested in this, you could take a look at the > above code, and see if you can work out how to modify it to make it work > with kgdb. But you will need a PC that has a debug-capable xHCI > controller in order to test it. If you have PC or laptop with USB 3.0 > built-in that has the Windows 8 logo, I think there's a good chance you > already have one. Or, according to > http://pete.akeo.ie/2011/08/do-necrenesas-upd720200-based-usb-30.html, > plug-in USB 3.0 host cards that use the newer Renesas uPD720201 chipset > also have the debug capability. > > Note that the above patch is against a pretty old kernel (3.6), so the > first thing you would need to do is forward-port it to work on the > latest kernel. As a plus, that would give you some real experience > working with kernel code, which everyone seems to agree you need ;) > > -- > Paul > Paul , My computer is rather old now as of Sandy Bridge days, so I probably can't test the patch on my own machine. However I will look at the code and see if I can forward port it against the usb git tree I have a current version of. In addition I would like the new xhci maintainers information in order to send out a patch with the Maintainer for xhci updated. Regards Nick -- 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
