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 --- a/drivers/net/korina.c
  14 +++ b/drivers/net/korina.c
  15 @@ -199,7 +199,7 @@ static int korina_send_packet(struct sk_
  16         struct korina_private *lp = netdev_priv(dev);
  17         unsigned long flags;
  18         u32 length;
  19 -       u32 chain_index;
  20 +       u32 chain_prev, chain_next;
  21         struct dma_desc *td;
  22
  23         spin_lock_irqsave(&lp->lock, flags);
  24 @@ -231,8 +231,8 @@ static int korina_send_packet(struct sk_
  25         /* Setup the transmit descriptor. */
  26         dma_cache_inv((u32) td, sizeof(*td));
  27         td->ca = CPHYSADDR(skb->data);
  28 -       chain_index = (lp->tx_chain_tail - 1) &
  29 -                       KORINA_TDS_MASK;
  30 +       chain_prev = (lp->tx_chain_tail - 1) & KORINA_TDS_MASK;
  31 +       chain_next = (lp->tx_chain_tail + 1) & KORINA_TDS_MASK;
  32
  33         if (readl(&(lp->tx_dma_regs->dmandptr)) == 0) {
  34                 if (lp->tx_chain_status == desc_empty) {
  35 @@ -240,7 +240,7 @@ static int korina_send_packet(struct sk_
  36                         td->control = DMA_COUNT(length) |
  37                                         DMA_DESC_COF | DMA_DESC_IOF;
  38                         /* Move tail */
  39 -                       lp->tx_chain_tail = chain_index;
  40 +                       lp->tx_chain_tail = chain_next;
  41                         /* Write to NDPTR */
  42                         writel(CPHYSADDR(&lp->td_ring[lp->tx_chain_head]),
  43                                         &lp->tx_dma_regs->dmandptr);
  44 @@ -251,12 +251,12 @@ static int korina_send_packet(struct sk_
  45                         td->control = DMA_COUNT(length) |
  46                                         DMA_DESC_COF | DMA_DESC_IOF;
  47                         /* Link to prev */
  48 -                       lp->td_ring[chain_index].control &=
  49 +                       lp->td_ring[chain_prev].control &=
  50                                         ~DMA_DESC_COF;
  51                         /* Link to prev */
  52 -                       lp->td_ring[chain_index].link =  CPHYSADDR(td);
  53 +                       lp->td_ring[chain_prev].link =  CPHYSADDR(td);
  54                         /* Move tail */
  55 -                       lp->tx_chain_tail = chain_index;
  56 +                       lp->tx_chain_tail = chain_next;
  57                         /* Write to NDPTR */
  58                         writel(CPHYSADDR(&lp->td_ring[lp->tx_chain_head]),
  59                                         &(lp->tx_dma_regs->dmandptr));
  60 @@ -270,17 +270,17 @@ static int korina_send_packet(struct sk_
  61                         td->control = DMA_COUNT(length) |
  62                                         DMA_DESC_COF | DMA_DESC_IOF;
  63                         /* Move tail */
  64 -                       lp->tx_chain_tail = chain_index;
  65 +                       lp->tx_chain_tail = chain_next;
  66                         lp->tx_chain_status = desc_filled;
  67                         netif_stop_queue(dev);
  68                 } else {
  69                         /* Update tail */
  70                         td->control = DMA_COUNT(length) |
  71                                         DMA_DESC_COF | DMA_DESC_IOF;
  72 -                       lp->td_ring[chain_index].control &=
  73 +                       lp->td_ring[chain_prev].control &=
  74                                         ~DMA_DESC_COF;
  75 -                       lp->td_ring[chain_index].link =  CPHYSADDR(td);
  76 -                       lp->tx_chain_tail = chain_index;
  77 +                       lp->td_ring[chain_prev].link =  CPHYSADDR(td);
  78 +                       lp->tx_chain_tail = chain_next;
  79                 }
  80         }
  81         dma_cache_wback((u32) td, sizeof(*td));