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

   1 From: Felix Fietkau <nbd@nbd.name>
   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@nbd.name>
  10 ---
  11
  12 --- a/drivers/net/ethernet/broadcom/bgmac.c
  13 +++ b/drivers/net/ethernet/broadcom/bgmac.c
  14 @@ -562,18 +562,26 @@ 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 @@ -621,8 +629,6 @@ 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 @@ -645,15 +651,6 @@ 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 @@ -663,10 +660,10 @@ 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 @@ -698,8 +695,13 @@ 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 +                               goto error;
  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 @@ -708,6 +710,12 @@ static void bgmac_dma_init(struct bgmac
 101                 ring->start = 0;
 102                 ring->end = 0;
 103         }
 104 +
 105 +       return 0;
 106 +
 107 +error:
 108 +       bgmac_dma_cleanup(bgmac);
 109 +       return err;
 110  }
 111
 112  /**************************************************
 113 @@ -1183,11 +1191,8 @@ static void bgmac_enable(struct bgmac *b
 114  }
 115
 116  /* http://bcm-v4.sipsolutions.net/mac-gbit/gmac/chipinit */
 117 -static void bgmac_chip_init(struct bgmac *bgmac, bool full_init)
 118 +static void bgmac_chip_init(struct bgmac *bgmac)
 119  {
 120 -       struct bgmac_dma_ring *ring;
 121 -       int i;
 122 -
 123         /* 1 interrupt per received frame */
 124         bgmac_write(bgmac, BGMAC_INT_RECV_LAZY, 1 << BGMAC_IRL_FC_SHIFT);
 125
 126 @@ -1205,16 +1210,7 @@ static void bgmac_chip_init(struct bgmac
 127
 128         bgmac_write(bgmac, BGMAC_RXMAX_LENGTH, 32 + ETHER_MAX_LEN);
 129
 130 -       if (full_init) {
 131 -               bgmac_dma_init(bgmac);
 132 -               if (1) /* FIXME: is there any case we don't want IRQs? */
 133 -                       bgmac_chip_intrs_on(bgmac);
 134 -       } else {
 135 -               for (i = 0; i < BGMAC_MAX_RX_RINGS; i++) {
 136 -                       ring = &bgmac->rx_ring[i];
 137 -                       bgmac_dma_rx_enable(bgmac, ring);
 138 -               }
 139 -       }
 140 +       bgmac_chip_intrs_on(bgmac);
 141
 142         bgmac_enable(bgmac);
 143  }
 144 @@ -1274,23 +1270,27 @@ static int bgmac_open(struct net_device
 145         int err = 0;
 146
 147         bgmac_chip_reset(bgmac);
 148 +
 149 +       err = bgmac_dma_init(bgmac);
 150 +       if (err)
 151 +               return err;
 152 +
 153         /* Specs say about reclaiming rings here, but we do that in DMA init */
 154 -       bgmac_chip_init(bgmac, true);
 155 +       bgmac_chip_init(bgmac);
 156
 157         err = request_irq(bgmac->core->irq, bgmac_interrupt, IRQF_SHARED,
 158                           KBUILD_MODNAME, net_dev);
 159         if (err < 0) {
 160                 bgmac_err(bgmac, "IRQ request error: %d!\n", err);
 161 -               goto err_out;
 162 +               bgmac_dma_cleanup(bgmac);
 163 +               return err;
 164         }
 165         napi_enable(&bgmac->napi);
 166
 167         phy_start(bgmac->phy_dev);
 168
 169         netif_carrier_on(net_dev);
 170 -
 171 -err_out:
 172 -       return err;
 173 +       return 0;
 174  }
 175
 176  static int bgmac_stop(struct net_device *net_dev)
 177 @@ -1306,6 +1306,7 @@ static int bgmac_stop(struct net_device
 178         free_irq(bgmac->core->irq, net_dev);
 179
 180         bgmac_chip_reset(bgmac);
 181 +       bgmac_dma_cleanup(bgmac);
 182
 183         return 0;
 184  }