target/linux/rb532/patches-2.6.28/013-korina_fix_handling_tx_chain_tail.patch

   1 Originally this must have been a rewrite error when introducing
   2 'chain_index'. But the original driver did not use the previous chain
   3 item everywhere: when altering the address tx_chain_tail points to, it
   4 should move forward, not backwards.
   5 Also this is not an "index" but rather the penultimate element in the
   6 chain, so rename it accordingly.
   7
   8 Signed-off-by: Phil Sutter <n0-1@freewrt.org>
   9 ---
  10  drivers/net/korina.c |   22 +++++++++++-----------
  11  1 files changed, 11 insertions(+), 11 deletions(-)
  12
  13 diff --git a/drivers/net/korina.c b/drivers/net/korina.c
  14 index dced5e7..f200175 100644
  15 --- a/drivers/net/korina.c
  16 +++ b/drivers/net/korina.c
  17 @@ -199,7 +199,7 @@ static int korina_send_packet(struct sk_buff *skb, struct net_device *dev)
  18         struct korina_private *lp = netdev_priv(dev);
  19         unsigned long flags;
  20         u32 length;
  21 -       u32 chain_index;
  22 +       u32 chain_prev, chain_next;
  23         struct dma_desc *td;
  24
  25         spin_lock_irqsave(&lp->lock, flags);
  26 @@ -231,8 +231,8 @@ static int korina_send_packet(struct sk_buff *skb, struct net_device *dev)
  27         /* Setup the transmit descriptor. */
  28         dma_cache_inv((u32) td, sizeof(*td));
  29         td->ca = CPHYSADDR(skb->data);
  30 -       chain_index = (lp->tx_chain_tail - 1) &
  31 -                       KORINA_TDS_MASK;
  32 +       chain_prev = (lp->tx_chain_tail - 1) & KORINA_TDS_MASK;
  33 +       chain_next = (lp->tx_chain_tail + 1) & KORINA_TDS_MASK;
  34
  35         if (readl(&(lp->tx_dma_regs->dmandptr)) == 0) {
  36                 if (lp->tx_chain_status == desc_empty) {
  37 @@ -240,7 +240,7 @@ static int korina_send_packet(struct sk_buff *skb, struct net_device *dev)
  38                         td->control = DMA_COUNT(length) |
  39                                         DMA_DESC_COF | DMA_DESC_IOF;
  40                         /* Move tail */
  41 -                       lp->tx_chain_tail = chain_index;
  42 +                       lp->tx_chain_tail = chain_next;
  43                         /* Write to NDPTR */
  44                         writel(CPHYSADDR(&lp->td_ring[lp->tx_chain_head]),
  45                                         &lp->tx_dma_regs->dmandptr);
  46 @@ -251,12 +251,12 @@ static int korina_send_packet(struct sk_buff *skb, struct net_device *dev)
  47                         td->control = DMA_COUNT(length) |
  48                                         DMA_DESC_COF | DMA_DESC_IOF;
  49                         /* Link to prev */
  50 -                       lp->td_ring[chain_index].control &=
  51 +                       lp->td_ring[chain_prev].control &=
  52                                         ~DMA_DESC_COF;
  53                         /* Link to prev */
  54 -                       lp->td_ring[chain_index].link =  CPHYSADDR(td);
  55 +                       lp->td_ring[chain_prev].link =  CPHYSADDR(td);
  56                         /* Move tail */
  57 -                       lp->tx_chain_tail = chain_index;
  58 +                       lp->tx_chain_tail = chain_next;
  59                         /* Write to NDPTR */
  60                         writel(CPHYSADDR(&lp->td_ring[lp->tx_chain_head]),
  61                                         &(lp->tx_dma_regs->dmandptr));
  62 @@ -270,17 +270,17 @@ static int korina_send_packet(struct sk_buff *skb, struct net_device *dev)
  63                         td->control = DMA_COUNT(length) |
  64                                         DMA_DESC_COF | DMA_DESC_IOF;
  65                         /* Move tail */
  66 -                       lp->tx_chain_tail = chain_index;
  67 +                       lp->tx_chain_tail = chain_next;
  68                         lp->tx_chain_status = desc_filled;
  69                         netif_stop_queue(dev);
  70                 } else {
  71                         /* Update tail */
  72                         td->control = DMA_COUNT(length) |
  73                                         DMA_DESC_COF | DMA_DESC_IOF;
  74 -                       lp->td_ring[chain_index].control &=
  75 +                       lp->td_ring[chain_prev].control &=
  76                                         ~DMA_DESC_COF;
  77 -                       lp->td_ring[chain_index].link =  CPHYSADDR(td);
  78 -                       lp->tx_chain_tail = chain_index;
  79 +                       lp->td_ring[chain_prev].link =  CPHYSADDR(td);
  80 +                       lp->tx_chain_tail = chain_next;
  81                 }
  82         }
  83         dma_cache_wback((u32) td, sizeof(*td));
  84 --
  85 1.5.6.4
  86
  87