Messages in this thread Patch in this message | | | From | Paul Gortmaker <> | Subject | [34-longterm 123/247] p54pci: update receive dma buffers before and after processing | Date | Thu, 23 Jun 2011 13:33:11 -0400 |
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From: Christian Lamparter <chunkeey@googlemail.com>
------------------- This is a commit scheduled for the next v2.6.34 longterm release. If you see a problem with using this for longterm, please comment. -------------------
commit 0bf719dfdecc5552155cbec78e49fa06e531e35c upstream.
Documentation/DMA-API-HOWTO.txt states:
"DMA transfers need to be synced properly in order for the cpu and device to see the most uptodate and correct copy of the DMA buffer."
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> --- drivers/net/wireless/p54/p54pci.c | 14 +++++++++----- 1 files changed, 9 insertions(+), 5 deletions(-)
diff --git a/drivers/net/wireless/p54/p54pci.c b/drivers/net/wireless/p54/p54pci.c index e1e3972..5735b6b 100644 --- a/drivers/net/wireless/p54/p54pci.c +++ b/drivers/net/wireless/p54/p54pci.c @@ -199,6 +199,7 @@ static void p54p_check_rx_ring(struct ieee80211_hw *dev, u32 *index, while (i != idx) { u16 len; struct sk_buff *skb; + dma_addr_t dma_addr; desc = &ring[i]; len = le16_to_cpu(desc->len); skb = rx_buf[i]; @@ -216,17 +217,20 @@ static void p54p_check_rx_ring(struct ieee80211_hw *dev, u32 *index, len = priv->common.rx_mtu; } + dma_addr = le32_to_cpu(desc->host_addr); + pci_dma_sync_single_for_cpu(priv->pdev, dma_addr, + priv->common.rx_mtu + 32, PCI_DMA_FROMDEVICE); skb_put(skb, len); if (p54_rx(dev, skb)) { - pci_unmap_single(priv->pdev, - le32_to_cpu(desc->host_addr), - priv->common.rx_mtu + 32, - PCI_DMA_FROMDEVICE); + pci_unmap_single(priv->pdev, dma_addr, + priv->common.rx_mtu + 32, PCI_DMA_FROMDEVICE); rx_buf[i] = NULL; - desc->host_addr = 0; + desc->host_addr = cpu_to_le32(0); } else { skb_trim(skb, 0); + pci_dma_sync_single_for_device(priv->pdev, dma_addr, + priv->common.rx_mtu + 32, PCI_DMA_FROMDEVICE); desc->len = cpu_to_le16(priv->common.rx_mtu + 32); } -- 1.7.4.4
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