Author: hselasky
Date: Sat Jan 11 08:16:31 2014
New Revision: 260536
URL: http://svnweb.freebsd.org/changeset/base/260536
Log:
Optimise interrupt logic. Technically writing a zero to the XHCI USB
status register has no effect. Can happen when the interrupt vector is
shared.
MFC after: 1 week
Modified:
head/sys/dev/usb/controller/xhci.c
Modified: head/sys/dev/usb/controller/xhci.c
==============================================================================
--- head/sys/dev/usb/controller/xhci.c Sat Jan 11 08:10:01 2014
(r260535)
+++ head/sys/dev/usb/controller/xhci.c Sat Jan 11 08:16:31 2014
(r260536)
@@ -1584,11 +1584,11 @@ xhci_interrupt(struct xhci_softc *sc)
status = XREAD4(sc, oper, XHCI_USBSTS);
- /* acknowledge interrupts */
-
- XWRITE4(sc, oper, XHCI_USBSTS, status);
-
- DPRINTFN(16, "real interrupt (status=0x%08x)\n", status);
+ /* acknowledge interrupts, if any */
+ if (status != 0) {
+ XWRITE4(sc, oper, XHCI_USBSTS, status);
+ DPRINTFN(16, "real interrupt (status=0x%08x)\n", status);
+ }
temp = XREAD4(sc, runt, XHCI_IMAN(0));
_______________________________________________
svn-src-all@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/svn-src-all
To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
