target/linux/lantiq/patches-5.4/0710-net-lantiq-configure-burst-length-for-ethernet.patch

   1 From ec1a17a11aced3cd756e59d91ad6f50b7a2fabfb Mon Sep 17 00:00:00 2001
   2 From: Aleksander Jan Bajkowski <olek2@wp.pl>
   3 Date: Sun, 16 May 2021 15:52:06 +0200
   4 Subject: [PATCH 5/5] net: lantiq: configure burst length for ethernet
   5
   6 Configure the burst length for Ethernet. This improves Ethernet
   7 performance by 58%. According to the vendor BSP, 8W burst length
   8 is supported by ar9 and newer SoCs.
   9
  10 The NAT benchmark results on xRX200 (Down/Up):
  11 * 2W: 330 Mb/s
  12 * 4W: 432 Mb/s    372 Mb/s
  13 * 8W: 520 Mb/s    389 Mb/s
  14
  15 Tested on xRX200 and xRX330.
  16
  17 Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl>
  18 ---
  19  drivers/net/ethernet/lantiq_etop.c   | 21 ++++++++++++++++++---
  20  drivers/net/ethernet/lantiq_xrx200.c | 21 ++++++++++++++++++---
  21  2 files changed, 36 insertions(+), 6 deletions(-)
  22
  23 --- a/drivers/net/ethernet/lantiq_etop.c
  24 +++ b/drivers/net/ethernet/lantiq_etop.c
  25 @@ -148,6 +148,9 @@ struct ltq_etop_priv {
  26         struct ltq_etop_chan txch;
  27         struct ltq_etop_chan rxch;
  28
  29 +       int tx_burst_len;
  30 +       int rx_burst_len;
  31 +
  32         int tx_irq;
  33         int rx_irq;
  34
  35 @@ -399,7 +402,7 @@ ltq_etop_dma_init(struct net_device *dev
  36         int rx = priv->rx_irq - LTQ_DMA_ETOP;
  37         int err;
  38
  39 -       ltq_dma_init_port(DMA_PORT_ETOP);
  40 +       ltq_dma_init_port(DMA_PORT_ETOP, priv->tx_burst_len, priv->rx_burst_len);
  41
  42         priv->txch.dma.nr = tx;
  43         priv->txch.dma.dev = &priv->pdev->dev;
  44 @@ -676,8 +679,8 @@ ltq_etop_tx(struct sk_buff *skb, struct
  45                 return NETDEV_TX_BUSY;
  46         }
  47
  48 -       /* dma needs to start on a 16 byte aligned address */
  49 -       byte_offset = CPHYSADDR(skb->data) % 16;
  50 +       /* dma needs to start on a burst length value aligned address */
  51 +       byte_offset = CPHYSADDR(skb->data) % (priv->tx_burst_len * 4);
  52         priv->txch.skb[priv->txch.dma.desc] = skb;
  53
  54         netif_trans_update(dev);
  55 @@ -930,6 +933,18 @@ static int ltq_etop_probe(struct platfor
  56         spin_lock_init(&priv->lock);
  57         SET_NETDEV_DEV(dev, &pdev->dev);
  58
  59 +       err = device_property_read_u32(&pdev->dev, "lantiq,tx-burst-length", &priv->tx_burst_len);
  60 +       if (err < 0) {
  61 +               dev_err(&pdev->dev, "unable to read tx-burst-length property\n");
  62 +               return err;
  63 +       }
  64 +
  65 +       err = device_property_read_u32(&pdev->dev, "lantiq,rx-burst-length", &priv->rx_burst_len);
  66 +       if (err < 0) {
  67 +               dev_err(&pdev->dev, "unable to read rx-burst-length property\n");
  68 +               return err;
  69 +       }
  70 +
  71         netif_napi_add(dev, &priv->txch.napi, ltq_etop_poll_tx, 8);
  72         netif_napi_add(dev, &priv->rxch.napi, ltq_etop_poll_rx, 32);
  73         priv->txch.netdev = dev;
  74 --- a/drivers/net/ethernet/lantiq_xrx200.c
  75 +++ b/drivers/net/ethernet/lantiq_xrx200.c
  76 @@ -71,6 +71,9 @@ struct xrx200_priv {
  77         struct net_device *net_dev;
  78         struct device *dev;
  79
  80 +       int tx_burst_len;
  81 +       int rx_burst_len;
  82 +
  83         __iomem void *pmac_reg;
  84  };
  85
  86 @@ -315,8 +318,8 @@ static int xrx200_start_xmit(struct sk_b
  87         if (unlikely(dma_mapping_error(priv->dev, mapping)))
  88                 goto err_drop;
  89
  90 -       /* dma needs to start on a 16 byte aligned address */
  91 -       byte_offset = mapping % 16;
  92 +       /* dma needs to start on a burst length value aligned address */
  93 +       byte_offset = mapping % (priv->tx_burst_len * 4);
  94
  95         desc->addr = mapping - byte_offset;
  96         /* Make sure the address is written before we give it to HW */
  97 @@ -368,7 +371,7 @@ static int xrx200_dma_init(struct xrx200
  98         int ret = 0;
  99         int i;
 100
 101 -       ltq_dma_init_port(DMA_PORT_ETOP);
 102 +       ltq_dma_init_port(DMA_PORT_ETOP, priv->tx_burst_len, priv->rx_burst_len);
 103
 104         ch_rx->dma.nr = XRX200_DMA_RX;
 105         ch_rx->dma.dev = priv->dev;
 106 @@ -486,6 +489,18 @@ static int xrx200_probe(struct platform_
 107         if (err)
 108                 eth_hw_addr_random(net_dev);
 109
 110 +       err = device_property_read_u32(dev, "lantiq,tx-burst-length", &priv->tx_burst_len);
 111 +       if (err < 0) {
 112 +               dev_err(dev, "unable to read tx-burst-length property\n");
 113 +               return err;
 114 +       }
 115 +
 116 +       err = device_property_read_u32(dev, "lantiq,rx-burst-length", &priv->rx_burst_len);
 117 +       if (err < 0) {
 118 +               dev_err(dev, "unable to read rx-burst-length property\n");
 119 +               return err;
 120 +       }
 121 +
 122         /* bring up the dma engine and IP core */
 123         err = xrx200_dma_init(priv);
 124         if (err)