From 971617c3b761c876d686a2188220a33898c90e99 Mon Sep 17 00:00:00 2001 From: Tim Harvey Date: Wed, 19 Feb 2020 15:19:36 -0800 Subject: [PATCH] net: thunderx: workaround BGX TX Underflow issue While it is not yet understood why a TX underflow can easily occur for SGMII interfaces resulting in a TX wedge. It has been found that disabling/re-enabling the LMAC resolves the issue. Signed-off-by: Tim Harvey Reviewed-by: Robert Jones Signed-off-by: David S. Miller --- .../net/ethernet/cavium/thunder/thunder_bgx.c | 62 ++++++++++++++++++- .../net/ethernet/cavium/thunder/thunder_bgx.h | 9 +++ 2 files changed, 68 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/cavium/thunder/thunder_bgx.c b/drivers/net/ethernet/cavium/thunder/thunder_bgx.c index 17a4110c2e49..8ff28ed04b7f 100644 --- a/drivers/net/ethernet/cavium/thunder/thunder_bgx.c +++ b/drivers/net/ethernet/cavium/thunder/thunder_bgx.c @@ -410,10 +410,19 @@ void bgx_lmac_rx_tx_enable(int node, int bgx_idx, int lmacid, bool enable) lmac = &bgx->lmac[lmacid]; cfg = bgx_reg_read(bgx, lmacid, BGX_CMRX_CFG); - if (enable) + if (enable) { cfg |= CMR_PKT_RX_EN | CMR_PKT_TX_EN; - else + + /* enable TX FIFO Underflow interrupt */ + bgx_reg_modify(bgx, lmacid, BGX_GMP_GMI_TXX_INT_ENA_W1S, + GMI_TXX_INT_UNDFLW); + } else { cfg &= ~(CMR_PKT_RX_EN | CMR_PKT_TX_EN); + + /* Disable TX FIFO Underflow interrupt */ + bgx_reg_modify(bgx, lmacid, BGX_GMP_GMI_TXX_INT_ENA_W1C, + GMI_TXX_INT_UNDFLW); + } bgx_reg_write(bgx, lmacid, BGX_CMRX_CFG, cfg); if (bgx->is_rgx) @@ -1535,6 +1544,48 @@ static int bgx_init_phy(struct bgx *bgx) return bgx_init_of_phy(bgx); } +static irqreturn_t bgx_intr_handler(int irq, void *data) +{ + struct bgx *bgx = (struct bgx *)data; + u64 status, val; + int lmac; + + for (lmac = 0; lmac < bgx->lmac_count; lmac++) { + status = bgx_reg_read(bgx, lmac, BGX_GMP_GMI_TXX_INT); + if (status & GMI_TXX_INT_UNDFLW) { + pci_err(bgx->pdev, "BGX%d lmac%d UNDFLW\n", + bgx->bgx_id, lmac); + val = bgx_reg_read(bgx, lmac, BGX_CMRX_CFG); + val &= ~CMR_EN; + bgx_reg_write(bgx, lmac, BGX_CMRX_CFG, val); + val |= CMR_EN; + bgx_reg_write(bgx, lmac, BGX_CMRX_CFG, val); + } + /* clear interrupts */ + bgx_reg_write(bgx, lmac, BGX_GMP_GMI_TXX_INT, status); + } + + return IRQ_HANDLED; +} + +static void bgx_register_intr(struct pci_dev *pdev) +{ + struct bgx *bgx = pci_get_drvdata(pdev); + int ret; + + ret = pci_alloc_irq_vectors(pdev, BGX_LMAC_VEC_OFFSET, + BGX_LMAC_VEC_OFFSET, PCI_IRQ_ALL_TYPES); + if (ret < 0) { + pci_err(pdev, "Req for #%d msix vectors failed\n", + BGX_LMAC_VEC_OFFSET); + return; + } + ret = pci_request_irq(pdev, GMPX_GMI_TX_INT, bgx_intr_handler, NULL, + bgx, "BGX%d", bgx->bgx_id); + if (ret) + pci_free_irq(pdev, GMPX_GMI_TX_INT, bgx); +} + static int bgx_probe(struct pci_dev *pdev, const struct pci_device_id *ent) { int err; @@ -1550,7 +1601,7 @@ static int bgx_probe(struct pci_dev *pdev, const struct pci_device_id *ent) pci_set_drvdata(pdev, bgx); - err = pci_enable_device(pdev); + err = pcim_enable_device(pdev); if (err) { dev_err(dev, "Failed to enable PCI device\n"); pci_set_drvdata(pdev, NULL); @@ -1604,6 +1655,8 @@ static int bgx_probe(struct pci_dev *pdev, const struct pci_device_id *ent) bgx_init_hw(bgx); + bgx_register_intr(pdev); + /* Enable all LMACs */ for (lmac = 0; lmac < bgx->lmac_count; lmac++) { err = bgx_lmac_enable(bgx, lmac); @@ -1620,6 +1673,7 @@ static int bgx_probe(struct pci_dev *pdev, const struct pci_device_id *ent) err_enable: bgx_vnic[bgx->bgx_id] = NULL; + pci_free_irq(pdev, GMPX_GMI_TX_INT, bgx); err_release_regions: pci_release_regions(pdev); err_disable_device: @@ -1637,6 +1691,8 @@ static void bgx_remove(struct pci_dev *pdev) for (lmac = 0; lmac < bgx->lmac_count; lmac++) bgx_lmac_disable(bgx, lmac); + pci_free_irq(pdev, GMPX_GMI_TX_INT, bgx); + bgx_vnic[bgx->bgx_id] = NULL; pci_release_regions(pdev); pci_disable_device(pdev); diff --git a/drivers/net/ethernet/cavium/thunder/thunder_bgx.h b/drivers/net/ethernet/cavium/thunder/thunder_bgx.h index 25888706bdcd..cdea49392185 100644 --- a/drivers/net/ethernet/cavium/thunder/thunder_bgx.h +++ b/drivers/net/ethernet/cavium/thunder/thunder_bgx.h @@ -180,6 +180,15 @@ #define BGX_GMP_GMI_TXX_BURST 0x38228 #define BGX_GMP_GMI_TXX_MIN_PKT 0x38240 #define BGX_GMP_GMI_TXX_SGMII_CTL 0x38300 +#define BGX_GMP_GMI_TXX_INT 0x38500 +#define BGX_GMP_GMI_TXX_INT_W1S 0x38508 +#define BGX_GMP_GMI_TXX_INT_ENA_W1C 0x38510 +#define BGX_GMP_GMI_TXX_INT_ENA_W1S 0x38518 +#define GMI_TXX_INT_PTP_LOST BIT_ULL(4) +#define GMI_TXX_INT_LATE_COL BIT_ULL(3) +#define GMI_TXX_INT_XSDEF BIT_ULL(2) +#define GMI_TXX_INT_XSCOL BIT_ULL(1) +#define GMI_TXX_INT_UNDFLW BIT_ULL(0) #define BGX_MSIX_VEC_0_29_ADDR 0x400000 /* +(0..29) << 4 */ #define BGX_MSIX_VEC_0_29_CTL 0x400008 -- 2.30.2