From 26f41062f28de65e11d3cf353e52d0be73442be1 Mon Sep 17 00:00:00 2001
From: "Kay, Allen M" <allen.m.kay@intel.com>
Date: Thu, 26 Jan 2012 10:25:53 -0800
Subject: [PATCH] PCI: check for pci bar restore completion and retry
On some OEM systems, pci_restore_state() is called while FLR has not yet
completed. As a result, PCI BAR register restore is not successful. This fix
reads back the restored value and compares it with saved value and re-tries 10
times before giving up.
Signed-off-by: Jean Guyader <jean.guyader@eu.citrix.com>
Signed-off-by: Eric Chanudet <eric.chanudet@citrix.com>
Signed-off-by: Allen Kay <allen.m.kay@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
---
drivers/pci/pci.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 053670e09e2b9..9c89447e7b212 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -959,6 +959,7 @@ void pci_restore_state(struct pci_dev *dev)
{
int i;
u32 val;
+ int tries;
if (!dev->state_saved)
return;
@@ -973,12 +974,16 @@ void pci_restore_state(struct pci_dev *dev)
*/
for (i = 15; i >= 0; i--) {
pci_read_config_dword(dev, i * 4, &val);
- if (val != dev->saved_config_space[i]) {
+ tries = 10;
+ while (tries && val != dev->saved_config_space[i]) {
dev_dbg(&dev->dev, "restoring config "
"space at offset %#x (was %#x, writing %#x)\n",
i, val, (int)dev->saved_config_space[i]);
pci_write_config_dword(dev,i * 4,
dev->saved_config_space[i]);
+ pci_read_config_dword(dev, i * 4, &val);
+ mdelay(10);
+ tries--;
}
}
pci_restore_pcix_state(dev);
--
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