target/linux/generic/backport-5.10/610-v5.13-49-net-ethernet-mtk_eth_soc-rework-NAPI-callbacks.patch

   1 From db2c7b353db3b3f71b55f9ff4627d8a786446fbe Mon Sep 17 00:00:00 2001
   2 From: Ilya Lipnitskiy <ilya.lipnitskiy@gmail.com>
   3 Date: Thu, 22 Apr 2021 22:21:06 -0700
   4 Subject: [PATCH] net: ethernet: mtk_eth_soc: rework NAPI callbacks
   5
   6 Use napi_complete_done to communicate total TX and RX work done to NAPI.
   7 Count total RX work up instead of remaining work down for clarity.
   8 Remove unneeded local variables for clarity. Use do {} while instead of
   9 goto for clarity.
  10
  11 Suggested-by: Jakub Kicinski <kuba@kernel.org>
  12 Signed-off-by: Ilya Lipnitskiy <ilya.lipnitskiy@gmail.com>
  13 Signed-off-by: David S. Miller <davem@davemloft.net>
  14 ---
  15  drivers/net/ethernet/mediatek/mtk_eth_soc.c | 54 +++++++++------------
  16  1 file changed, 24 insertions(+), 30 deletions(-)
  17
  18 --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
  19 +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
  20 @@ -1531,7 +1531,6 @@ static void mtk_handle_status_irq(struct
  21  static int mtk_napi_tx(struct napi_struct *napi, int budget)
  22  {
  23         struct mtk_eth *eth = container_of(napi, struct mtk_eth, tx_napi);
  24 -       u32 status, mask;
  25         int tx_done = 0;
  26
  27         if (MTK_HAS_CAPS(eth->soc->caps, MTK_QDMA))
  28 @@ -1540,21 +1539,19 @@ static int mtk_napi_tx(struct napi_struc
  29         tx_done = mtk_poll_tx(eth, budget);
  30
  31         if (unlikely(netif_msg_intr(eth))) {
  32 -               status = mtk_r32(eth, eth->tx_int_status_reg);
  33 -               mask = mtk_r32(eth, eth->tx_int_mask_reg);
  34                 dev_info(eth->dev,
  35 -                        "done tx %d, intr 0x%08x/0x%x\n",
  36 -                        tx_done, status, mask);
  37 +                        "done tx %d, intr 0x%08x/0x%x\n", tx_done,
  38 +                        mtk_r32(eth, eth->tx_int_status_reg),
  39 +                        mtk_r32(eth, eth->tx_int_mask_reg));
  40         }
  41
  42         if (tx_done == budget)
  43                 return budget;
  44
  45 -       status = mtk_r32(eth, eth->tx_int_status_reg);
  46 -       if (status & MTK_TX_DONE_INT)
  47 +       if (mtk_r32(eth, eth->tx_int_status_reg) & MTK_TX_DONE_INT)
  48                 return budget;
  49
  50 -       if (napi_complete(napi))
  51 +       if (napi_complete_done(napi, tx_done))
  52                 mtk_tx_irq_enable(eth, MTK_TX_DONE_INT);
  53
  54         return tx_done;
  55 @@ -1563,36 +1560,33 @@ static int mtk_napi_tx(struct napi_struc
  56  static int mtk_napi_rx(struct napi_struct *napi, int budget)
  57  {
  58         struct mtk_eth *eth = container_of(napi, struct mtk_eth, rx_napi);
  59 -       u32 status, mask;
  60 -       int rx_done = 0;
  61 -       int remain_budget = budget;
  62 +       int rx_done_total = 0;
  63
  64         mtk_handle_status_irq(eth);
  65
  66 -poll_again:
  67 -       mtk_w32(eth, MTK_RX_DONE_INT, MTK_PDMA_INT_STATUS);
  68 -       rx_done = mtk_poll_rx(napi, remain_budget, eth);
  69 +       do {
  70 +               int rx_done;
  71
  72 -       if (unlikely(netif_msg_intr(eth))) {
  73 -               status = mtk_r32(eth, MTK_PDMA_INT_STATUS);
  74 -               mask = mtk_r32(eth, MTK_PDMA_INT_MASK);
  75 -               dev_info(eth->dev,
  76 -                        "done rx %d, intr 0x%08x/0x%x\n",
  77 -                        rx_done, status, mask);
  78 -       }
  79 -       if (rx_done == remain_budget)
  80 -               return budget;
  81 +               mtk_w32(eth, MTK_RX_DONE_INT, MTK_PDMA_INT_STATUS);
  82 +               rx_done = mtk_poll_rx(napi, budget - rx_done_total, eth);
  83 +               rx_done_total += rx_done;
  84 +
  85 +               if (unlikely(netif_msg_intr(eth))) {
  86 +                       dev_info(eth->dev,
  87 +                                "done rx %d, intr 0x%08x/0x%x\n", rx_done,
  88 +                                mtk_r32(eth, MTK_PDMA_INT_STATUS),
  89 +                                mtk_r32(eth, MTK_PDMA_INT_MASK));
  90 +               }
  91
  92 -       status = mtk_r32(eth, MTK_PDMA_INT_STATUS);
  93 -       if (status & MTK_RX_DONE_INT) {
  94 -               remain_budget -= rx_done;
  95 -               goto poll_again;
  96 -       }
  97 +               if (rx_done_total == budget)
  98 +                       return budget;
  99 +
 100 +       } while (mtk_r32(eth, MTK_PDMA_INT_STATUS) & MTK_RX_DONE_INT);
 101
 102 -       if (napi_complete(napi))
 103 +       if (napi_complete_done(napi, rx_done_total))
 104                 mtk_rx_irq_enable(eth, MTK_RX_DONE_INT);
 105
 106 -       return rx_done + budget - remain_budget;
 107 +       return rx_done_total;
 108  }
 109
 110  static int mtk_tx_alloc(struct mtk_eth *eth)