target/linux/generic/backport-5.15/729-06-v6.1-net-ethernet-mtk_eth_soc-do-not-overwrite-mtu-config.patch

   1 From: Lorenzo Bianconi <lorenzo@kernel.org>
   2 Date: Thu, 17 Nov 2022 00:35:04 +0100
   3 Subject: [PATCH] net: ethernet: mtk_eth_soc: do not overwrite mtu
   4  configuration running reset routine
   5
   6 Restore user configured MTU running mtk_hw_init() during tx timeout routine
   7 since it will be overwritten after a hw reset.
   8
   9 Reported-by: Felix Fietkau <nbd@nbd.name>
  10 Fixes: 9ea4d311509f ("net: ethernet: mediatek: add the whole ethernet reset into the reset process")
  11 Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
  12 Signed-off-by: David S. Miller <davem@davemloft.net>
  13 ---
  14
  15 --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
  16 +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
  17 @@ -3175,6 +3175,30 @@ static void mtk_dim_tx(struct work_struc
  18         dim->state = DIM_START_MEASURE;
  19  }
  20
  21 +static void mtk_set_mcr_max_rx(struct mtk_mac *mac, u32 val)
  22 +{
  23 +       struct mtk_eth *eth = mac->hw;
  24 +       u32 mcr_cur, mcr_new;
  25 +
  26 +       if (MTK_HAS_CAPS(eth->soc->caps, MTK_SOC_MT7628))
  27 +               return;
  28 +
  29 +       mcr_cur = mtk_r32(mac->hw, MTK_MAC_MCR(mac->id));
  30 +       mcr_new = mcr_cur & ~MAC_MCR_MAX_RX_MASK;
  31 +
  32 +       if (val <= 1518)
  33 +               mcr_new |= MAC_MCR_MAX_RX(MAC_MCR_MAX_RX_1518);
  34 +       else if (val <= 1536)
  35 +               mcr_new |= MAC_MCR_MAX_RX(MAC_MCR_MAX_RX_1536);
  36 +       else if (val <= 1552)
  37 +               mcr_new |= MAC_MCR_MAX_RX(MAC_MCR_MAX_RX_1552);
  38 +       else
  39 +               mcr_new |= MAC_MCR_MAX_RX(MAC_MCR_MAX_RX_2048);
  40 +
  41 +       if (mcr_new != mcr_cur)
  42 +               mtk_w32(mac->hw, mcr_new, MTK_MAC_MCR(mac->id));
  43 +}
  44 +
  45  static int mtk_hw_init(struct mtk_eth *eth)
  46  {
  47         u32 dma_mask = ETHSYS_DMA_AG_MAP_PDMA | ETHSYS_DMA_AG_MAP_QDMA |
  48 @@ -3249,8 +3273,16 @@ static int mtk_hw_init(struct mtk_eth *e
  49          * up with the more appropriate value when mtk_mac_config call is being
  50          * invoked.
  51          */
  52 -       for (i = 0; i < MTK_MAC_COUNT; i++)
  53 +       for (i = 0; i < MTK_MAC_COUNT; i++) {
  54 +               struct net_device *dev = eth->netdev[i];
  55 +
  56                 mtk_w32(eth, MAC_MCR_FORCE_LINK_DOWN, MTK_MAC_MCR(i));
  57 +               if (dev) {
  58 +                       struct mtk_mac *mac = netdev_priv(dev);
  59 +
  60 +                       mtk_set_mcr_max_rx(mac, dev->mtu + MTK_RX_ETH_HLEN);
  61 +               }
  62 +       }
  63
  64         /* Indicates CDM to parse the MTK special tag from CPU
  65          * which also is working out for untag packets.
  66 @@ -3366,7 +3398,6 @@ static int mtk_change_mtu(struct net_dev
  67         int length = new_mtu + MTK_RX_ETH_HLEN;
  68         struct mtk_mac *mac = netdev_priv(dev);
  69         struct mtk_eth *eth = mac->hw;
  70 -       u32 mcr_cur, mcr_new;
  71
  72         if (rcu_access_pointer(eth->prog) &&
  73             length > MTK_PP_MAX_BUF_SIZE) {
  74 @@ -3374,23 +3405,7 @@ static int mtk_change_mtu(struct net_dev
  75                 return -EINVAL;
  76         }
  77
  78 -       if (!MTK_HAS_CAPS(eth->soc->caps, MTK_SOC_MT7628)) {
  79 -               mcr_cur = mtk_r32(mac->hw, MTK_MAC_MCR(mac->id));
  80 -               mcr_new = mcr_cur & ~MAC_MCR_MAX_RX_MASK;
  81 -
  82 -               if (length <= 1518)
  83 -                       mcr_new |= MAC_MCR_MAX_RX(MAC_MCR_MAX_RX_1518);
  84 -               else if (length <= 1536)
  85 -                       mcr_new |= MAC_MCR_MAX_RX(MAC_MCR_MAX_RX_1536);
  86 -               else if (length <= 1552)
  87 -                       mcr_new |= MAC_MCR_MAX_RX(MAC_MCR_MAX_RX_1552);
  88 -               else
  89 -                       mcr_new |= MAC_MCR_MAX_RX(MAC_MCR_MAX_RX_2048);
  90 -
  91 -               if (mcr_new != mcr_cur)
  92 -                       mtk_w32(mac->hw, mcr_new, MTK_MAC_MCR(mac->id));
  93 -       }
  94 -
  95 +       mtk_set_mcr_max_rx(mac, length);
  96         dev->mtu = new_mtu;
  97
  98         return 0;