diff options
| author |   Jesse Brandeburg <jesse.brandeburg@intel.com> | 2011-07-20 00:56:21 +0000 |
|---|---|---|
| committer |   Jeff Kirsher <jeffrey.t.kirsher@intel.com> | 2011-08-04 04:59:07 -0700 |
| commit | 945a51517cc0bd9e461f2018624dfc1faef9ddee (patch) | |
| tree | 5782ffe27f3fb8f5b4cbc19ffe7b74bff36c6a05 /drivers/net/ixgbe/ixgbe_ethtool.c | |
| parent | macb: restore wrap bit when performing underrun cleanup (diff) | |
| download | linux-dev-945a51517cc0bd9e461f2018624dfc1faef9ddee.tar.xz linux-dev-945a51517cc0bd9e461f2018624dfc1faef9ddee.zip | |
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/ixgbe/ixgbe_ethtool.c')
| -rw-r--r-- | drivers/net/ixgbe/ixgbe_ethtool.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/net/ixgbe/ixgbe_ethtool.c b/drivers/net/ixgbe/ixgbe_ethtool.c index dc649553a0a6..82d4244c6e10 100644 --- a/drivers/net/ixgbe/ixgbe_ethtool.c +++ b/drivers/net/ixgbe/ixgbe_ethtool.c @@ -1378,6 +1378,7 @@ static int ixgbe_intr_test(struct ixgbe_adapter *adapter, u64 *data) /* Disable all the interrupts */ IXGBE_WRITE_REG(&adapter->hw, IXGBE_EIMC, 0xFFFFFFFF); + IXGBE_WRITE_FLUSH(&adapter->hw); usleep_range(10000, 20000); /* Test each interrupt */ @@ -1398,6 +1399,7 @@ static int ixgbe_intr_test(struct ixgbe_adapter *adapter, u64 *data) ~mask & 0x00007FFF); IXGBE_WRITE_REG(&adapter->hw, IXGBE_EICS, ~mask & 0x00007FFF); + IXGBE_WRITE_FLUSH(&adapter->hw); usleep_range(10000, 20000); if (adapter->test_icr & mask) { @@ -1415,6 +1417,7 @@ static int ixgbe_intr_test(struct ixgbe_adapter *adapter, u64 *data) adapter->test_icr = 0; IXGBE_WRITE_REG(&adapter->hw, IXGBE_EIMS, mask); IXGBE_WRITE_REG(&adapter->hw, IXGBE_EICS, mask); + IXGBE_WRITE_FLUSH(&adapter->hw); usleep_range(10000, 20000); if (!(adapter->test_icr &mask)) { @@ -1435,6 +1438,7 @@ static int ixgbe_intr_test(struct ixgbe_adapter *adapter, u64 *data) ~mask & 0x00007FFF); IXGBE_WRITE_REG(&adapter->hw, IXGBE_EICS, ~mask & 0x00007FFF); + IXGBE_WRITE_FLUSH(&adapter->hw); usleep_range(10000, 20000); if (adapter->test_icr) { @@ -1446,6 +1450,7 @@ static int ixgbe_intr_test(struct ixgbe_adapter *adapter, u64 *data) /* Disable all the interrupts */ IXGBE_WRITE_REG(&adapter->hw, IXGBE_EIMC, 0xFFFFFFFF); + IXGBE_WRITE_FLUSH(&adapter->hw); usleep_range(10000, 20000); /* Unhook test interrupt handler */ |