diff options
| author | Jesse Brandeburg <jesse.brandeburg@intel.com> | 2011-07-20 04:56:21 +0400 |
|---|---|---|
| committer | Jeff Kirsher <jeffrey.t.kirsher@intel.com> | 2011-08-04 15:59:07 +0400 |
| commit | 945a51517cc0bd9e461f2018624dfc1faef9ddee (patch) | |
| tree | 5782ffe27f3fb8f5b4cbc19ffe7b74bff36c6a05 /drivers/net/igb/igb_ethtool.c | |
| parent | d3e614577198757d5854caa912e88f2d4296479b (diff) | |
| download | linux-945a51517cc0bd9e461f2018624dfc1faef9ddee.tar.xz | |
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>
Diffstat (limited to 'drivers/net/igb/igb_ethtool.c')
| -rw-r--r-- | drivers/net/igb/igb_ethtool.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/net/igb/igb_ethtool.c b/drivers/net/igb/igb_ethtool.c index ff244ce803ce..414b0225be89 100644 --- a/drivers/net/igb/igb_ethtool.c +++ b/drivers/net/igb/igb_ethtool.c @@ -1225,6 +1225,7 @@ static int igb_intr_test(struct igb_adapter *adapter, u64 *data) /* Disable all the interrupts */ wr32(E1000_IMC, ~0); + wrfl(); msleep(10); /* Define all writable bits for ICS */ @@ -1268,6 +1269,7 @@ static int igb_intr_test(struct igb_adapter *adapter, u64 *data) wr32(E1000_IMC, mask); wr32(E1000_ICS, mask); + wrfl(); msleep(10); if (adapter->test_icr & mask) { @@ -1289,6 +1291,7 @@ static int igb_intr_test(struct igb_adapter *adapter, u64 *data) wr32(E1000_IMS, mask); wr32(E1000_ICS, mask); + wrfl(); msleep(10); if (!(adapter->test_icr & mask)) { @@ -1310,6 +1313,7 @@ static int igb_intr_test(struct igb_adapter *adapter, u64 *data) wr32(E1000_IMC, ~mask); wr32(E1000_ICS, ~mask); + wrfl(); msleep(10); if (adapter->test_icr & mask) { @@ -1321,6 +1325,7 @@ static int igb_intr_test(struct igb_adapter *adapter, u64 *data) /* Disable all the interrupts */ wr32(E1000_IMC, ~0); + wrfl(); msleep(10); /* Unhook test interrupt handler */ |