So far the TX-FIFO is only used with a depth of 1, although the hardware offers a depth of 2. The workaround for the chips that are affected by erratum 6, i.e. EFF frames may be send as standard frames, is to re-send the EFF frame. This means the driver cannot queue the next frame for sending, as long ad the EFF frame has not been successfully send out. Introduce rkcanfd_get_effective_tx_free() that returns "0" space in the TX-FIFO if an EFF frame is pending and the actual free space in the TX-FIFO otherwise. Then replace rkcanfd_get_tx_free() with rkcanfd_get_effective_tx_free() everywhere. Tested-by: Alibek Omarov <a1ba.omarov@xxxxxxxxx> Acked-by: Heiko Stuebner <heiko@xxxxxxxxx> Link: https://patch.msgid.link/20240904-rockchip-canfd-v5-16-8ae22bcb27cc@xxxxxxxxxxxxxx Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> --- drivers/net/can/rockchip/rockchip_canfd-rx.c | 2 +- drivers/net/can/rockchip/rockchip_canfd-tx.c | 38 ++++++++++++++++++-- drivers/net/can/rockchip/rockchip_canfd.h | 1 + 3 files changed, 38 insertions(+), 3 deletions(-) diff --git a/drivers/net/can/rockchip/rockchip_canfd-rx.c b/drivers/net/can/rockchip/rockchip_canfd-rx.c index 9f72483dab18..bacef5e5dc39 100644 --- a/drivers/net/can/rockchip/rockchip_canfd-rx.c +++ b/drivers/net/can/rockchip/rockchip_canfd-rx.c @@ -124,7 +124,7 @@ static int rkcanfd_rxstx_filter(struct rkcanfd_priv *priv, WRITE_ONCE(priv->tx_tail, priv->tx_tail + 1); netif_subqueue_completed_wake(priv->ndev, 0, 1, frame_len, - rkcanfd_get_tx_free(priv), + rkcanfd_get_effective_tx_free(priv), RKCANFD_TX_START_THRESHOLD); *tx_done = true; diff --git a/drivers/net/can/rockchip/rockchip_canfd-tx.c b/drivers/net/can/rockchip/rockchip_canfd-tx.c index f8e74e814b3b..d10da548ba71 100644 --- a/drivers/net/can/rockchip/rockchip_canfd-tx.c +++ b/drivers/net/can/rockchip/rockchip_canfd-tx.c @@ -8,6 +8,40 @@ #include "rockchip_canfd.h" +static bool rkcanfd_tx_tail_is_eff(const struct rkcanfd_priv *priv) +{ + const struct canfd_frame *cfd; + const struct sk_buff *skb; + unsigned int tx_tail; + + if (!rkcanfd_get_tx_pending(priv)) + return false; + + tx_tail = rkcanfd_get_tx_tail(priv); + skb = priv->can.echo_skb[tx_tail]; + if (!skb) { + netdev_err(priv->ndev, + "%s: echo_skb[%u]=NULL tx_head=0x%08x tx_tail=0x%08x\n", + __func__, tx_tail, + priv->tx_head, priv->tx_tail); + + return false; + } + + cfd = (struct canfd_frame *)skb->data; + + return cfd->can_id & CAN_EFF_FLAG; +} + +unsigned int rkcanfd_get_effective_tx_free(const struct rkcanfd_priv *priv) +{ + if (priv->devtype_data.quirks & RKCANFD_QUIRK_RK3568_ERRATUM_6 && + rkcanfd_tx_tail_is_eff(priv)) + return 0; + + return rkcanfd_get_tx_free(priv); +} + static void rkcanfd_start_xmit_write_cmd(const struct rkcanfd_priv *priv, const u32 reg_cmd) { @@ -42,7 +76,7 @@ int rkcanfd_start_xmit(struct sk_buff *skb, struct net_device *ndev) return NETDEV_TX_OK; if (!netif_subqueue_maybe_stop(priv->ndev, 0, - rkcanfd_get_tx_free(priv), + rkcanfd_get_effective_tx_free(priv), RKCANFD_TX_STOP_THRESHOLD, RKCANFD_TX_START_THRESHOLD)) { if (net_ratelimit()) @@ -99,7 +133,7 @@ int rkcanfd_start_xmit(struct sk_buff *skb, struct net_device *ndev) rkcanfd_start_xmit_write_cmd(priv, reg_cmd); netif_subqueue_maybe_stop(priv->ndev, 0, - rkcanfd_get_tx_free(priv), + rkcanfd_get_effective_tx_free(priv), RKCANFD_TX_STOP_THRESHOLD, RKCANFD_TX_START_THRESHOLD); diff --git a/drivers/net/can/rockchip/rockchip_canfd.h b/drivers/net/can/rockchip/rockchip_canfd.h index f24a1d18be66..37d90400429f 100644 --- a/drivers/net/can/rockchip/rockchip_canfd.h +++ b/drivers/net/can/rockchip/rockchip_canfd.h @@ -533,6 +533,7 @@ int rkcanfd_handle_rx_int(struct rkcanfd_priv *priv); void rkcanfd_timestamp_init(struct rkcanfd_priv *priv); +unsigned int rkcanfd_get_effective_tx_free(const struct rkcanfd_priv *priv); void rkcanfd_xmit_retry(struct rkcanfd_priv *priv); int rkcanfd_start_xmit(struct sk_buff *skb, struct net_device *ndev); void rkcanfd_handle_tx_done_one(struct rkcanfd_priv *priv, const u32 ts, -- 2.45.2