target/linux/octeontx/patches-4.14/0001-net-thunderx-workaround-BGX-TX-Underflow-issue.patch

   1 From b1e7791e688620c9bb8476ac2d0bc99abeb7f825 Mon Sep 17 00:00:00 2001
   2 From: Tim Harvey <tharvey@gateworks.com>
   3 Date: Fri, 29 Dec 2017 16:48:04 -0800
   4 Subject: [PATCH] net: thunderx: workaround BGX TX Underflow issue
   5
   6 While it is not yet understood why a TX underflow can easily occur
   7 for SGMII interfaces resulting in a TX wedge. It has been found that
   8 disabling/re-enabling the LMAC resolves the issue.
   9
  10 Signed-off-by: Tim Harvey <tharvey@gateworks.com>
  11 ---
  12  drivers/net/ethernet/cavium/thunder/thunder_bgx.c | 54 +++++++++++++++++++++++
  13  drivers/net/ethernet/cavium/thunder/thunder_bgx.h |  9 ++++
  14  2 files changed, 63 insertions(+)
  15
  16 diff --git a/drivers/net/ethernet/cavium/thunder/thunder_bgx.c b/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
  17 index 805c02a..0690966 100644
  18 --- a/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
  19 +++ b/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
  20 @@ -1344,6 +1344,54 @@ static int bgx_init_phy(struct bgx *bgx)
  21         return bgx_init_of_phy(bgx);
  22  }
  23
  24 +static irqreturn_t bgx_intr_handler(int irq, void *data)
  25 +{
  26 +       struct bgx *bgx = (struct bgx *)data;
  27 +       struct device *dev = &bgx->pdev->dev;
  28 +       u64 status, val;
  29 +       int lmac;
  30 +
  31 +       for (lmac = 0; lmac < bgx->lmac_count; lmac++) {
  32 +               status = bgx_reg_read(bgx, lmac, BGX_GMP_GMI_TXX_INT);
  33 +               if (status & GMI_TXX_INT_UNDFLW) {
  34 +                       dev_err(dev, "BGX%d lmac%d UNDFLW\n", bgx->bgx_id,
  35 +                               lmac);
  36 +                       val = bgx_reg_read(bgx, lmac, BGX_CMRX_CFG);
  37 +                       val &= ~CMR_EN;
  38 +                       bgx_reg_write(bgx, lmac, BGX_CMRX_CFG, val);
  39 +                       val |= CMR_EN;
  40 +                       bgx_reg_write(bgx, lmac, BGX_CMRX_CFG, val);
  41 +               }
  42 +               /* clear interrupts */
  43 +               bgx_reg_write(bgx, lmac, BGX_GMP_GMI_TXX_INT, status);
  44 +       }
  45 +
  46 +       return IRQ_HANDLED;
  47 +}
  48 +
  49 +static int bgx_register_intr(struct pci_dev *pdev)
  50 +{
  51 +       struct bgx *bgx = pci_get_drvdata(pdev);
  52 +       struct device *dev = &pdev->dev;
  53 +       int num_vec, ret;
  54 +       char irq_name[32];
  55 +
  56 +       /* Enable MSI-X */
  57 +       num_vec = pci_msix_vec_count(pdev);
  58 +       ret = pci_alloc_irq_vectors(pdev, num_vec, num_vec, PCI_IRQ_MSIX);
  59 +       if (ret < 0) {
  60 +               dev_err(dev, "Req for #%d msix vectors failed\n", num_vec);
  61 +               return 1;
  62 +       }
  63 +       sprintf(irq_name, "BGX%d", bgx->bgx_id);
  64 +       ret = request_irq(pci_irq_vector(pdev, GMPX_GMI_TX_INT),
  65 +               bgx_intr_handler, 0, irq_name, bgx);
  66 +       if (ret)
  67 +               return 1;
  68 +
  69 +       return 0;
  70 +}
  71 +
  72  static int bgx_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
  73  {
  74         int err;
  75 @@ -1414,6 +1462,8 @@ static int bgx_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
  76                 xcv_init_hw(bgx->phy_mode);
  77         bgx_init_hw(bgx);
  78
  79 +       bgx_register_intr(pdev);
  80 +
  81         /* Enable all LMACs */
  82         for (lmac = 0; lmac < bgx->lmac_count; lmac++) {
  83                 err = bgx_lmac_enable(bgx, lmac);
  84 @@ -1424,6 +1474,10 @@ static int bgx_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
  85                                 bgx_lmac_disable(bgx, --lmac);
  86                         goto err_enable;
  87                 }
  88 +
  89 +               /* enable TX FIFO Underflow interrupt */
  90 +               bgx_reg_modify(bgx, lmac, BGX_GMP_GMI_TXX_INT_ENA_W1S,
  91 +                              GMI_TXX_INT_UNDFLW);
  92         }
  93
  94         return 0;
  95 diff --git a/drivers/net/ethernet/cavium/thunder/thunder_bgx.h b/drivers/net/ethernet/cavium/thunder/thunder_bgx.h
  96 index 2bba9d1..be9148f9 100644
  97 --- a/drivers/net/ethernet/cavium/thunder/thunder_bgx.h
  98 +++ b/drivers/net/ethernet/cavium/thunder/thunder_bgx.h
  99 @@ -179,6 +179,15 @@
 100  #define BGX_GMP_GMI_TXX_BURST          0x38228
 101  #define BGX_GMP_GMI_TXX_MIN_PKT                0x38240
 102  #define BGX_GMP_GMI_TXX_SGMII_CTL      0x38300
 103 +#define BGX_GMP_GMI_TXX_INT            0x38500
 104 +#define BGX_GMP_GMI_TXX_INT_W1S                0x38508
 105 +#define BGX_GMP_GMI_TXX_INT_ENA_W1C    0x38510
 106 +#define BGX_GMP_GMI_TXX_INT_ENA_W1S    0x38518
 107 +#define  GMI_TXX_INT_PTP_LOST                  BIT_ULL(4)
 108 +#define  GMI_TXX_INT_LATE_COL                  BIT_ULL(3)
 109 +#define  GMI_TXX_INT_XSDEF                     BIT_ULL(2)
 110 +#define  GMI_TXX_INT_XSCOL                     BIT_ULL(1)
 111 +#define  GMI_TXX_INT_UNDFLW                    BIT_ULL(0)
 112
 113  #define BGX_MSIX_VEC_0_29_ADDR         0x400000 /* +(0..29) << 4 */
 114  #define BGX_MSIX_VEC_0_29_CTL          0x400008
 115 --
 116 2.7.4
 117