From: Carolyn Wyborny <carolyn.wyborny@intel.com>
Date: Sat, 25 Jun 2011 13:18:12 +0000 (+0000)
Subject: igb: Fix lack of flush after register write and before delay
X-Git-Tag: firefly_0821_release~7541^2~2870
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=80b5405f36fba0caa9a142f978c00afa6aa7714c;p=firefly-linux-kernel-4.4.55.git

igb: Fix lack of flush after register write and before delay

commit 064b43304ed8ede8e13ff7b4338d09fd37bcffb1 upstream.

Register writes followed by a delay are required to have a flush
before the delay in order to commit the values to the register.  Without
the flush, the code following the delay may not function correctly.

Reported-by: Tong Ho <tong.ho@ericsson.com>
Reported-by: Guenter Roeck <guenter.roeck@ericsson.com>
Signed-off-by: Carolyn Wyborny <carolyn.wyborny@intel.com>
Tested-by:  Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/drivers/net/igb/e1000_82575.c b/drivers/net/igb/e1000_82575.c
index 0f563c8c5ffc..493e331d7064 100644
--- a/drivers/net/igb/e1000_82575.c
+++ b/drivers/net/igb/e1000_82575.c
@@ -1735,6 +1735,7 @@ static s32 igb_reset_hw_82580(struct e1000_hw *hw)
 		ctrl |= E1000_CTRL_RST;
 
 	wr32(E1000_CTRL, ctrl);
+	wrfl();
 
 	/* Add delay to insure DEV_RST has time to complete */
 	if (global_device_reset)