From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1LAqYz-0005pQ-NN for qemu-devel@nongnu.org; Thu, 11 Dec 2008 13:47:05 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1LAqYz-0005oJ-3O for qemu-devel@nongnu.org; Thu, 11 Dec 2008 13:47:05 -0500 Received: from [199.232.76.173] (port=46283 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1LAqYy-0005oA-Pu for qemu-devel@nongnu.org; Thu, 11 Dec 2008 13:47:04 -0500 Received: from hera.kernel.org ([140.211.167.34]:49828) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1LAqYy-0000zr-88 for qemu-devel@nongnu.org; Thu, 11 Dec 2008 13:47:04 -0500 Message-ID: <49416013.6040305@kernel.org> Date: Thu, 11 Dec 2008 10:46:43 -0800 From: Max Krasnyansky MIME-Version: 1.0 References: <43d6ff410811270605p61259au5f3101f97bedf288@mail.gmail.com> <43d6ff410812010207n30dc83bcp946ad86165268af9@mail.gmail.com> In-Reply-To: <43d6ff410812010207n30dc83bcp946ad86165268af9@mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: [Qemu-devel] Re: USB-OHCI / UHCI: Isochronous transfer not working on Linux host Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Thomas Bandelier Cc: mark.burkley@emutex.com, "lemagoup@gmail.com" , "qemu-devel@nongnu.org" , "Krasnyanskiy, Maksim (Max)" , Arnon Gilboa Sorry for delay in replying. (CCing Mark Burkley who recently posted EHCI patches) Thomas Bandelier wrote: > Hi Arnon, Max, Pierre, > > Arnon, Thanks for your feedback on this point. > > As we need to manage several USB 2.0 devices in our environment, we are > going to work on this aspect. We are very motivated to make it work. > > Do you (Max and/or Arnon) have any idea of what should be done / > reworked in order to support USB 2.0 devices and especially isochronous > transfers in QEMU? Most USB 2.0 devices should work just fine with the current UHCI code. Including isochronous transfers. While developing new UHCI implementation I was testing it with several 2.0 devices like USB storage devices and MS Webcam. Webcam uses isoc transfers and worked fairly well. However since UHCI does not do 2.0 rates USB bandwidth is much lower in the guest. > We would prefer keeping OHCI implementation, but do you think we should > switch to UHCI? Or maybe EHCI? > > If we can keep OHCI, what should we begin to do in order to debug > current QEMU OHCI implementation? Same question for the other > controllers if we have to switch. Ideally we need to switch to EHCI in order to support high USB2.0 speeds. Not too long ago Mark posted a EHCI implementation (I have not had much luck with it and XP yet though). Otherwise if you're ok with lower BW then UHCI should work fine. Max