svn commit: r239103 - head/sys/dev/pci

[John Baldwin]

Author: jhb
Date: Mon Aug  6 19:49:57 2012
New Revision: 239103
URL: http://svn.freebsd.org/changeset/base/239103

Log:
  Explicitly enable busmastering on PCI-PCI bridges.  Transactions initiated
  on the secondary side of a bridge will not be propagated to the primary
  bus unless this is enabled.  Busmastering is not enabled by default (we
  have relied on firmware to set this bit to date).  The OS needs to set it
  for any bridges not configured by system firmware.
  
  Tested by:	Steve Polyack  korvus comcast net
  MFC after:	2 weeks

Modified:
  head/sys/dev/pci/pci_pci.c

Modified: head/sys/dev/pci/pci_pci.c
==============================================================================
--- head/sys/dev/pci/pci_pci.c	Mon Aug  6 18:54:17 2012	(r239102)
+++ head/sys/dev/pci/pci_pci.c	Mon Aug  6 19:49:57 2012	(r239103)
@@ -683,6 +683,13 @@ pcib_attach_common(device_t dev)
      *     would be more widely routed than absolutely necessary.  We could
      *     then do a walk of the tree later and fix it.
      */
+
+    /*
+     * Always enable busmastering on bridges so that transactions
+     * initiated on the secondary bus are passed through to the
+     * primary bus.
+     */
+    pci_enable_busmaster(dev);
 }
 
 int