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| author | David Woodhouse <David.Woodhouse@intel.com> | 2012-12-19 11:01:21 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2012-12-19 14:53:53 -0800 |
| commit | 152a2a8b5e1d4cbe91a7c66f1028db15164a3766 (patch) | |
| tree | 2a3cc4287755749cc5e4e6a7fe837ab69b6a5703 | |
| parent | 13af816469db3449c072afbae6c4c1bd9ccecccb (diff) | |
| download | lwn-152a2a8b5e1d4cbe91a7c66f1028db15164a3766.tar.gz lwn-152a2a8b5e1d4cbe91a7c66f1028db15164a3766.zip | |
solos-pci: ensure all TX packets are aligned to 4 bytes
The FPGA can't handled unaligned DMA (yet). So copy into an aligned buffer,
if skb->data isn't suitably aligned.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | drivers/atm/solos-pci.c | 27 |
1 files changed, 23 insertions, 4 deletions
diff --git a/drivers/atm/solos-pci.c b/drivers/atm/solos-pci.c index aa4f35d52a92..d70abe77f737 100644 --- a/drivers/atm/solos-pci.c +++ b/drivers/atm/solos-pci.c @@ -128,9 +128,11 @@ struct solos_card { struct sk_buff_head cli_queue[4]; struct sk_buff *tx_skb[4]; struct sk_buff *rx_skb[4]; + unsigned char *dma_bounce; wait_queue_head_t param_wq; wait_queue_head_t fw_wq; int using_dma; + int dma_alignment; int fpga_version; int buffer_size; int atmel_flash; @@ -1083,7 +1085,12 @@ static uint32_t fpga_tx(struct solos_card *card) tx_started |= 1 << port; oldskb = skb; /* We're done with this skb already */ } else if (skb && card->using_dma) { - SKB_CB(skb)->dma_addr = pci_map_single(card->dev, skb->data, + unsigned char *data = skb->data; + if ((unsigned long)data & card->dma_alignment) { + data = card->dma_bounce + (BUF_SIZE * port); + memcpy(data, skb->data, skb->len); + } + SKB_CB(skb)->dma_addr = pci_map_single(card->dev, data, skb->len, PCI_DMA_TODEVICE); card->tx_skb[port] = skb; iowrite32(SKB_CB(skb)->dma_addr, @@ -1261,18 +1268,27 @@ static int fpga_probe(struct pci_dev *dev, const struct pci_device_id *id) else card->atmel_flash = 0; + data32 = ioread32(card->config_regs + PORTS); + card->nr_ports = (data32 & 0x000000FF); + if (card->fpga_version >= DMA_SUPPORTED) { pci_set_master(dev); card->using_dma = 1; + if (1) { /* All known FPGA versions so far */ + card->dma_alignment = 3; + card->dma_bounce = kmalloc(card->nr_ports * BUF_SIZE, GFP_KERNEL); + if (!card->dma_bounce) { + dev_warn(&card->dev->dev, "Failed to allocate DMA bounce buffers\n"); + /* Fallback to MMIO doesn't work */ + goto out_unmap_both; + } + } } else { card->using_dma = 0; /* Set RX empty flag for all ports */ iowrite32(0xF0, card->config_regs + FLAGS_ADDR); } - data32 = ioread32(card->config_regs + PORTS); - card->nr_ports = (data32 & 0x000000FF); - pci_set_drvdata(dev, card); tasklet_init(&card->tlet, solos_bh, (unsigned long)card); @@ -1319,6 +1335,7 @@ static int fpga_probe(struct pci_dev *dev, const struct pci_device_id *id) tasklet_kill(&card->tlet); out_unmap_both: + kfree(card->dma_bounce); pci_set_drvdata(dev, NULL); pci_iounmap(dev, card->buffers); out_unmap_config: @@ -1429,6 +1446,8 @@ static void fpga_remove(struct pci_dev *dev) free_irq(dev->irq, card); tasklet_kill(&card->tlet); + kfree(card->dma_bounce); + /* Release device from reset */ iowrite32(0, card->config_regs + FPGA_MODE); (void)ioread32(card->config_regs + FPGA_MODE); |