target/linux/generic/patches-3.18/077-10-bgmac-simplify-dma-init-cleanup.patch

   1 From: Felix Fietkau <nbd@openwrt.org>
   2 Date: Sun, 12 Apr 2015 23:19:32 +0200
   3 Subject: [PATCH] bgmac: simplify dma init/cleanup
   4
   5 Instead of allocating buffers at device init time and initializing
   6 descriptors at device open, do both at the same time (during open).
   7 Free all buffers when closing the device.
   8
   9 Signed-off-by: Felix Fietkau <nbd@openwrt.org>
  10 ---
  11
  12 --- a/drivers/net/ethernet/broadcom/bgmac.c
  13 +++ b/drivers/net/ethernet/broadcom/bgmac.c
  14 @@ -545,18 +545,26 @@ static void bgmac_dma_ring_desc_free(str
  15                           ring->dma_base);
  16  }
  17
  18 -static void bgmac_dma_free(struct bgmac *bgmac)
  19 +static void bgmac_dma_cleanup(struct bgmac *bgmac)
  20  {
  21         int i;
  22
  23 -       for (i = 0; i < BGMAC_MAX_TX_RINGS; i++) {
  24 +       for (i = 0; i < BGMAC_MAX_TX_RINGS; i++)
  25                 bgmac_dma_tx_ring_free(bgmac, &bgmac->tx_ring[i]);
  26 -               bgmac_dma_ring_desc_free(bgmac, &bgmac->tx_ring[i]);
  27 -       }
  28 -       for (i = 0; i < BGMAC_MAX_RX_RINGS; i++) {
  29 +
  30 +       for (i = 0; i < BGMAC_MAX_RX_RINGS; i++)
  31                 bgmac_dma_rx_ring_free(bgmac, &bgmac->rx_ring[i]);
  32 +}
  33 +
  34 +static void bgmac_dma_free(struct bgmac *bgmac)
  35 +{
  36 +       int i;
  37 +
  38 +       for (i = 0; i < BGMAC_MAX_TX_RINGS; i++)
  39 +               bgmac_dma_ring_desc_free(bgmac, &bgmac->tx_ring[i]);
  40 +
  41 +       for (i = 0; i < BGMAC_MAX_RX_RINGS; i++)
  42                 bgmac_dma_ring_desc_free(bgmac, &bgmac->rx_ring[i]);
  43 -       }
  44  }
  45
  46  static int bgmac_dma_alloc(struct bgmac *bgmac)
  47 @@ -604,8 +612,6 @@ static int bgmac_dma_alloc(struct bgmac
  48         }
  49
  50         for (i = 0; i < BGMAC_MAX_RX_RINGS; i++) {
  51 -               int j;
  52 -
  53                 ring = &bgmac->rx_ring[i];
  54                 ring->num_slots = BGMAC_RX_RING_SLOTS;
  55                 ring->mmio_base = ring_base[i];
  56 @@ -628,15 +634,6 @@ static int bgmac_dma_alloc(struct bgmac
  57                         ring->index_base = lower_32_bits(ring->dma_base);
  58                 else
  59                         ring->index_base = 0;
  60 -
  61 -               /* Alloc RX slots */
  62 -               for (j = 0; j < ring->num_slots; j++) {
  63 -                       err = bgmac_dma_rx_skb_for_slot(bgmac, &ring->slots[j]);
  64 -                       if (err) {
  65 -                               bgmac_err(bgmac, "Can't allocate skb for slot in RX ring\n");
  66 -                               goto err_dma_free;
  67 -                       }
  68 -               }
  69         }
  70
  71         return 0;
  72 @@ -646,10 +643,10 @@ err_dma_free:
  73         return -ENOMEM;
  74  }
  75
  76 -static void bgmac_dma_init(struct bgmac *bgmac)
  77 +static int bgmac_dma_init(struct bgmac *bgmac)
  78  {
  79         struct bgmac_dma_ring *ring;
  80 -       int i;
  81 +       int i, err;
  82
  83         for (i = 0; i < BGMAC_MAX_TX_RINGS; i++) {
  84                 ring = &bgmac->tx_ring[i];
  85 @@ -681,8 +678,13 @@ static void bgmac_dma_init(struct bgmac
  86                 if (ring->unaligned)
  87                         bgmac_dma_rx_enable(bgmac, ring);
  88
  89 -               for (j = 0; j < ring->num_slots; j++)
  90 +               for (j = 0; j < ring->num_slots; j++) {
  91 +                       err = bgmac_dma_rx_skb_for_slot(bgmac, &ring->slots[j]);
  92 +                       if (err)
  93 +                               return err;
  94 +
  95                         bgmac_dma_rx_setup_desc(bgmac, ring, j);
  96 +               }
  97
  98                 bgmac_write(bgmac, ring->mmio_base + BGMAC_DMA_RX_INDEX,
  99                             ring->index_base +
 100 @@ -691,6 +693,8 @@ static void bgmac_dma_init(struct bgmac
 101                 ring->start = 0;
 102                 ring->end = 0;
 103         }
 104 +
 105 +       return 0;
 106  }
 107
 108  /**************************************************
 109 @@ -1166,11 +1170,8 @@ static void bgmac_enable(struct bgmac *b
 110  }
 111
 112  /* http://bcm-v4.sipsolutions.net/mac-gbit/gmac/chipinit */
 113 -static void bgmac_chip_init(struct bgmac *bgmac, bool full_init)
 114 +static void bgmac_chip_init(struct bgmac *bgmac)
 115  {
 116 -       struct bgmac_dma_ring *ring;
 117 -       int i;
 118 -
 119         /* 1 interrupt per received frame */
 120         bgmac_write(bgmac, BGMAC_INT_RECV_LAZY, 1 << BGMAC_IRL_FC_SHIFT);
 121
 122 @@ -1188,16 +1189,7 @@ static void bgmac_chip_init(struct bgmac
 123
 124         bgmac_write(bgmac, BGMAC_RXMAX_LENGTH, 32 + ETHER_MAX_LEN);
 125
 126 -       if (full_init) {
 127 -               bgmac_dma_init(bgmac);
 128 -               if (1) /* FIXME: is there any case we don't want IRQs? */
 129 -                       bgmac_chip_intrs_on(bgmac);
 130 -       } else {
 131 -               for (i = 0; i < BGMAC_MAX_RX_RINGS; i++) {
 132 -                       ring = &bgmac->rx_ring[i];
 133 -                       bgmac_dma_rx_enable(bgmac, ring);
 134 -               }
 135 -       }
 136 +       bgmac_chip_intrs_on(bgmac);
 137
 138         bgmac_enable(bgmac);
 139  }
 140 @@ -1257,8 +1249,13 @@ static int bgmac_open(struct net_device
 141         int err = 0;
 142
 143         bgmac_chip_reset(bgmac);
 144 +
 145 +       err = bgmac_dma_init(bgmac);
 146 +       if (err)
 147 +               goto err_out;
 148 +
 149         /* Specs say about reclaiming rings here, but we do that in DMA init */
 150 -       bgmac_chip_init(bgmac, true);
 151 +       bgmac_chip_init(bgmac);
 152
 153         err = request_irq(bgmac->core->irq, bgmac_interrupt, IRQF_SHARED,
 154                           KBUILD_MODNAME, net_dev);
 155 @@ -1273,6 +1270,7 @@ static int bgmac_open(struct net_device
 156         netif_carrier_on(net_dev);
 157
 158  err_out:
 159 +       bgmac_dma_cleanup(bgmac);
 160         return err;
 161  }
 162
 163 @@ -1289,6 +1287,7 @@ static int bgmac_stop(struct net_device
 164         free_irq(bgmac->core->irq, net_dev);
 165
 166         bgmac_chip_reset(bgmac);
 167 +       bgmac_dma_cleanup(bgmac);
 168
 169         return 0;
 170  }