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.
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 4289dc0ced0d..fa7913ef415d 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 d604994755d3..d719a52258e3 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 b736a10e8f1f..3c1d61c8632f 100644
--- a/drivers/net/can/rockchip/rockchip_canfd.h
+++ b/drivers/net/can/rockchip/rockchip_canfd.h
@@ -532,6 +532,7 @@ 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,
--
2.43.0
