[Xen-changelog] [xen-unstable] xend: Restore bridge control register after secondary bus reset

[Xen patchbot-unstable <patchbot-unstable@xxxxxxxxxxxxxxxxxxx>]

# HG changeset patch
# User Keir Fraser <keir.fraser@xxxxxxxxxx>
# Date 1223635946 -3600
# Node ID 365674de23c225fb5bec546d41c074e8634355b0
# Parent  60bd590a0438e55f1bdd08c01cc6a4932a9b922e
xend: Restore bridge control register after secondary bus reset

From: Chris Dalton <cid@xxxxxx>
Signed-off-by: Keir Fraser <keir.fraser@xxxxxxxxxx>
---
 tools/python/xen/util/pci.py |    9 ++++++---
 1 files changed, 6 insertions(+), 3 deletions(-)

diff -r 60bd590a0438 -r 365674de23c2 tools/python/xen/util/pci.py
--- a/tools/python/xen/util/pci.py      Fri Oct 10 10:18:06 2008 +0100
+++ b/tools/python/xen/util/pci.py      Fri Oct 10 11:52:26 2008 +0100
@@ -475,14 +475,17 @@ class PciDevice:
         sysfs_mnt = find_sysfs_mnt()
         parent_path = sysfs_mnt + SYSFS_PCI_DEVS_PATH + '/' + \
             target_bus + SYSFS_PCI_DEV_CONFIG_PATH
-        fd = os.open(parent_path, os.O_WRONLY)
+        fd = os.open(parent_path, os.O_RDWR)
+        # Save state of bridge control register - restore after reset
+        os.lseek(fd, PCI_CB_BRIDGE_CONTROL, 0)
+        br_cntl = (struct.unpack('H', os.read(fd, 2)))[0]
         # Assert Secondary Bus Reset
         os.lseek(fd, PCI_CB_BRIDGE_CONTROL, 0)
         os.write(fd, struct.pack('I', PCI_BRIDGE_CTL_BUS_RESET))
         time.sleep(0.200)
         # De-assert Secondary Bus Reset
-        os.lseek(fd, 0x3e, 0)
-        os.write(fd, struct.pack('I', 0x00))
+        os.lseek(fd, PCI_CB_BRIDGE_CONTROL, 0)
+        os.write(fd, struct.pack('H', br_cntl))
         time.sleep(0.200)
         os.close(fd)
 

_______________________________________________
Xen-changelog mailing list
Xen-changelog@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-changelog