intel drivers: repair missing flush operations

after review of all intel drivers, found several instances where
drivers had the incorrect pattern of:
memory mapped write();
delay();

which should always be:
memory mapped write();
write flush(); /* aka memory mapped read */
delay();

explanation:
The reason for including the flush is that writes can be held
(posted) in PCI/PCIe bridges, but the read always has to complete
synchronously and therefore has to flush all pending writes to a
device.  If a write is held and followed by a delay, the delay
means nothing because the write may not have reached hardware
(maybe even not until the next read)

Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by:  Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/net/e1000e/phy.c b/drivers/net/e1000e/phy.c
index 2a6ee13285b1..8666476cb9be 100644
--- a/drivers/net/e1000e/phy.c
+++ b/drivers/net/e1000e/phy.c
@@ -537,6 +537,7 @@ static s32 __e1000_read_kmrn_reg(struct e1000_hw *hw, u32 offset, u16 *data,
 	kmrnctrlsta = ((offset << E1000_KMRNCTRLSTA_OFFSET_SHIFT) &
 		       E1000_KMRNCTRLSTA_OFFSET) | E1000_KMRNCTRLSTA_REN;
 	ew32(KMRNCTRLSTA, kmrnctrlsta);
+	e1e_flush();
 
 	udelay(2);
 
@@ -609,6 +610,7 @@ static s32 __e1000_write_kmrn_reg(struct e1000_hw *hw, u32 offset, u16 data,
 	kmrnctrlsta = ((offset << E1000_KMRNCTRLSTA_OFFSET_SHIFT) &
 		       E1000_KMRNCTRLSTA_OFFSET) | data;
 	ew32(KMRNCTRLSTA, kmrnctrlsta);
+	e1e_flush();
 
 	udelay(2);