diff options
| author | Fenghua Yu <fenghua.yu@intel.com> | 2009-02-18 15:54:33 -0800 |
|---|---|---|
| committer | John W. Linville <linville@tuxdriver.com> | 2009-02-27 14:52:47 -0500 |
| commit | 96891ceedaeaac95aa5b9dba5e68a8e77d541e78 (patch) | |
| tree | 4f0666a793ec60dbd4194755d076b5c7ae709807 /drivers/net/wireless/iwlwifi/iwl-agn.c | |
| parent | 7dc45f25d39ea959fdc1d5f636e9fc6cbe7ac7e0 (diff) | |
iwlwifi: dma mapping read and write changes
When iwlwifi runs on IOMMU, IOMMU generates a lot of PTE write faults
because PTE write bit is not set on some of PTE's. This is because iwlwifi
driver calls DMA mapping with PCI_DMA_TODEVICE which is read only in mapping
PTE. But iwlwifi device actually writes to the mapped page to update its contents.
This issue is not exposed in swiotlb. But VT-d hardware can capture this fault and
stop the fault transaction.
The iwl TX command contains a scratch field that is updated by uCode to
indicate retry counts. For 5000 series the patch is required also for
regular frames, but this patch does not differenciate.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Acked-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Diffstat (limited to 'drivers/net/wireless/iwlwifi/iwl-agn.c')
| -rw-r--r-- | drivers/net/wireless/iwlwifi/iwl-agn.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/net/wireless/iwlwifi/iwl-agn.c b/drivers/net/wireless/iwlwifi/iwl-agn.c index bcb94a01f94..b49f9f7a8a6 100644 --- a/drivers/net/wireless/iwlwifi/iwl-agn.c +++ b/drivers/net/wireless/iwlwifi/iwl-agn.c @@ -444,7 +444,7 @@ void iwl_hw_txq_free_tfd(struct iwl_priv *priv, struct iwl_tx_queue *txq) pci_unmap_single(dev, pci_unmap_addr(&txq->cmd[index]->meta, mapping), pci_unmap_len(&txq->cmd[index]->meta, len), - PCI_DMA_TODEVICE); + PCI_DMA_BIDIRECTIONAL); /* Unmap chunks, if any. */ for (i = 1; i < num_tbs; i++) { |