Tests show that sometimes both CAN bus error counters read 0x0, even if the controller is in warning mode (RKCANFD_REG_STATE_ERROR_WARNING_STATE in RKCANFD_REG_STATE set). To work around this issue, if both error counters read from hardware are 0x0, use the structure priv->bec, otherwise save the read value in priv->bec. In rkcanfd_handle_rx_int_one() decrement the priv->bec.rxerr for successfully RX'ed CAN frames. In rkcanfd_handle_tx_done_one() decrement the priv->bec.txerr for successfully TX'ed CAN frames. Tested-by: Alibek Omarov <a1ba.omarov@xxxxxxxxx> Acked-by: Heiko Stuebner <heiko@xxxxxxxxx> Link: https://patch.msgid.link/20240904-rockchip-canfd-v5-14-8ae22bcb27cc@xxxxxxxxxxxxxx Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> --- .../net/can/rockchip/rockchip_canfd-core.c | 50 ++++++++++++++++--- drivers/net/can/rockchip/rockchip_canfd-rx.c | 15 ++++++ drivers/net/can/rockchip/rockchip_canfd-tx.c | 8 +++ drivers/net/can/rockchip/rockchip_canfd.h | 2 + 4 files changed, 69 insertions(+), 6 deletions(-) diff --git a/drivers/net/can/rockchip/rockchip_canfd-core.c b/drivers/net/can/rockchip/rockchip_canfd-core.c index 700702e4d2ed..cf176180a282 100644 --- a/drivers/net/can/rockchip/rockchip_canfd-core.c +++ b/drivers/net/can/rockchip/rockchip_canfd-core.c @@ -159,11 +159,47 @@ static int rkcanfd_set_bittiming(struct rkcanfd_priv *priv) return 0; } -static void rkcanfd_get_berr_counter_raw(struct rkcanfd_priv *priv, - struct can_berr_counter *bec) +static void rkcanfd_get_berr_counter_corrected(struct rkcanfd_priv *priv, + struct can_berr_counter *bec) { + struct can_berr_counter bec_raw; + u32 reg_state; + bec->rxerr = rkcanfd_read(priv, RKCANFD_REG_RXERRORCNT); bec->txerr = rkcanfd_read(priv, RKCANFD_REG_TXERRORCNT); + bec_raw = *bec; + + /* Tests show that sometimes both CAN bus error counters read + * 0x0, even if the controller is in warning mode + * (RKCANFD_REG_STATE_ERROR_WARNING_STATE in RKCANFD_REG_STATE + * set). + * + * In case both error counters read 0x0, use the struct + * priv->bec, otherwise save the read value to priv->bec. + * + * rkcanfd_handle_rx_int_one() handles the decrementing of + * priv->bec.rxerr for successfully RX'ed CAN frames. + * + * Luckily the controller doesn't decrement the RX CAN bus + * error counter in hardware for self received TX'ed CAN + * frames (RKCANFD_REG_MODE_RXSTX_MODE), so RXSTX doesn't + * interfere with proper RX CAN bus error counters. + * + * rkcanfd_handle_tx_done_one() handles the decrementing of + * priv->bec.txerr for successfully TX'ed CAN frames. + */ + if (!bec->rxerr && !bec->txerr) + *bec = priv->bec; + else + priv->bec = *bec; + + reg_state = rkcanfd_read(priv, RKCANFD_REG_STATE); + netdev_vdbg(priv->ndev, + "%s: Raw/Cor: txerr=%3u/%3u rxerr=%3u/%3u Bus Off=%u Warning=%u\n", + __func__, + bec_raw.txerr, bec->txerr, bec_raw.rxerr, bec->rxerr, + !!(reg_state & RKCANFD_REG_STATE_BUS_OFF_STATE), + !!(reg_state & RKCANFD_REG_STATE_ERROR_WARNING_STATE)); } static int rkcanfd_get_berr_counter(const struct net_device *ndev, @@ -176,7 +212,7 @@ static int rkcanfd_get_berr_counter(const struct net_device *ndev, if (err) return err; - rkcanfd_get_berr_counter_raw(priv, bec); + rkcanfd_get_berr_counter_corrected(priv, bec); pm_runtime_put(ndev->dev.parent); @@ -252,6 +288,8 @@ static void rkcanfd_chip_start(struct rkcanfd_priv *priv) RKCANFD_REG_INT_OVERLOAD_INT | RKCANFD_REG_INT_TX_FINISH_INT; + memset(&priv->bec, 0x0, sizeof(priv->bec)); + rkcanfd_chip_fifo_setup(priv); rkcanfd_timestamp_init(priv); rkcanfd_set_bittiming(priv); @@ -488,7 +526,7 @@ static int rkcanfd_handle_error_int(struct rkcanfd_priv *priv) if (cf) { struct can_berr_counter bec; - rkcanfd_get_berr_counter_raw(priv, &bec); + rkcanfd_get_berr_counter_corrected(priv, &bec); cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR | CAN_ERR_CNT; cf->data[6] = bec.txerr; cf->data[7] = bec.rxerr; @@ -517,7 +555,7 @@ static int rkcanfd_handle_state_error_int(struct rkcanfd_priv *priv) u32 timestamp; int err; - rkcanfd_get_berr_counter_raw(priv, &bec); + rkcanfd_get_berr_counter_corrected(priv, &bec); can_state_get_by_berr_counter(ndev, &bec, &tx_state, &rx_state); new_state = max(tx_state, rx_state); @@ -570,7 +608,7 @@ rkcanfd_handle_rx_fifo_overflow_int(struct rkcanfd_priv *priv) if (skb) return 0; - rkcanfd_get_berr_counter_raw(priv, &bec); + rkcanfd_get_berr_counter_corrected(priv, &bec); cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT; cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; diff --git a/drivers/net/can/rockchip/rockchip_canfd-rx.c b/drivers/net/can/rockchip/rockchip_canfd-rx.c index 31cee3362f1e..eff08948840c 100644 --- a/drivers/net/can/rockchip/rockchip_canfd-rx.c +++ b/drivers/net/can/rockchip/rockchip_canfd-rx.c @@ -167,6 +167,13 @@ static int rkcanfd_rxstx_filter(struct rkcanfd_priv *priv, /* Affected by Erratum 6 */ + /* Manual handling of CAN Bus Error counters. See + * rkcanfd_get_corrected_berr_counter() for detailed + * explanation. + */ + if (priv->bec.txerr) + priv->bec.txerr--; + *tx_done = true; stats->tx_packets++; @@ -229,6 +236,14 @@ static int rkcanfd_handle_rx_int_one(struct rkcanfd_priv *priv) return 0; } + /* Manual handling of CAN Bus Error counters. See + * rkcanfd_get_corrected_berr_counter() for detailed + * explanation. + */ + if (priv->bec.rxerr) + priv->bec.rxerr = min(CAN_ERROR_PASSIVE_THRESHOLD, + priv->bec.rxerr) - 1; + if (header->frameinfo & RKCANFD_REG_FD_FRAMEINFO_FDF) skb = alloc_canfd_skb(priv->ndev, &skb_cfd); else diff --git a/drivers/net/can/rockchip/rockchip_canfd-tx.c b/drivers/net/can/rockchip/rockchip_canfd-tx.c index 9db6d90a4e7f..f8e74e814b3b 100644 --- a/drivers/net/can/rockchip/rockchip_canfd-tx.c +++ b/drivers/net/can/rockchip/rockchip_canfd-tx.c @@ -113,6 +113,14 @@ void rkcanfd_handle_tx_done_one(struct rkcanfd_priv *priv, const u32 ts, unsigned int tx_tail; tx_tail = rkcanfd_get_tx_tail(priv); + + /* Manual handling of CAN Bus Error counters. See + * rkcanfd_get_corrected_berr_counter() for detailed + * explanation. + */ + if (priv->bec.txerr) + priv->bec.txerr--; + stats->tx_bytes += can_rx_offload_get_echo_skb_queue_timestamp(&priv->offload, tx_tail, ts, diff --git a/drivers/net/can/rockchip/rockchip_canfd.h b/drivers/net/can/rockchip/rockchip_canfd.h index 3fe6ddcdd8ac..67f135fbcfb9 100644 --- a/drivers/net/can/rockchip/rockchip_canfd.h +++ b/drivers/net/can/rockchip/rockchip_canfd.h @@ -459,6 +459,8 @@ struct rkcanfd_priv { u32 reg_int_mask_default; struct rkcanfd_devtype_data devtype_data; + struct can_berr_counter bec; + struct reset_control *reset; struct clk_bulk_data *clks; int clks_num; -- 2.45.2
