Date: Fri, 6 Mar 2009 17:13:12 +0000 (UTC) From: Andrew Thompson <thompsa@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r189453 - head/sys/dev/usb/controller Message-ID: <200903061713.n26HDCe9024679@svn.freebsd.org>
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Author: thompsa Date: Fri Mar 6 17:13:12 2009 New Revision: 189453 URL: http://svn.freebsd.org/changeset/base/189453 Log: MFp4 //depot/projects/usb@158692 Workaround a EHCI performance problem by issuing a doorbell after queueing a bulk xfer. Submitted by: Hans Petter Selasky Modified: head/sys/dev/usb/controller/ehci.c Modified: head/sys/dev/usb/controller/ehci.c ============================================================================== --- head/sys/dev/usb/controller/ehci.c Fri Mar 6 17:04:47 2009 (r189452) +++ head/sys/dev/usb/controller/ehci.c Fri Mar 6 17:13:12 2009 (r189453) @@ -2189,12 +2189,21 @@ static void ehci_device_bulk_start(struct usb2_xfer *xfer) { ehci_softc_t *sc = EHCI_BUS2SC(xfer->xroot->bus); + uint32_t temp; /* setup TD's and QH */ ehci_setup_standard_chain(xfer, &sc->sc_async_p_last); /* put transfer on interrupt queue */ ehci_transfer_intr_enqueue(xfer); + + /* XXX Performance quirk: Some Host Controllers have a too low + * interrupt rate. Issue an IAAD to stimulate the Host + * Controller after queueing the BULK transfer. + */ + temp = EOREAD4(sc, EHCI_USBCMD); + if (!(temp & EHCI_CMD_IAAD)) + EOWRITE4(sc, EHCI_USBCMD, temp | EHCI_CMD_IAAD); } struct usb2_pipe_methods ehci_device_bulk_methods =
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