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authorJakub Kicinski <kuba@kernel.org>2022-09-28 10:48:38 -0700
committerJakub Kicinski <kuba@kernel.org>2022-09-28 10:48:38 -0700
commitaf2faee54d591904050d69a55b6e429565bbe389 (patch)
tree2d0b8ff8cbd043fc2db81c6a64576bdb6b72e153
parent44d70bb561dac9363f45787aa93dfca36877ee01 (diff)
parent81d192c2ce74157e717e1fc4b68791f82f7499d4 (diff)
downloadlinux-sgx-af2faee54d591904050d69a55b6e429565bbe389.tar.gz
Merge tag 'linux-can-fixes-for-6.0-20220928' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can
Marc Kleine-Budde says: ==================== pull-request: can 2022-09-28 The patch is by me and targets the c_can driver. It disables an optimization in the TX path of C_CAN cores which causes problems. * tag 'linux-can-fixes-for-6.0-20220928' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can: can: c_can: don't cache TX messages for C_CAN cores ==================== Link: https://lore.kernel.org/r/20220928090629.1124190-1-mkl@pengutronix.de Signed-off-by: Jakub Kicinski <kuba@kernel.org>
-rw-r--r--drivers/net/can/c_can/c_can.h17
-rw-r--r--drivers/net/can/c_can/c_can_main.c11
2 files changed, 20 insertions, 8 deletions
diff --git a/drivers/net/can/c_can/c_can.h b/drivers/net/can/c_can/c_can.h
index f23a03300a81e3..029cd8194ed54e 100644
--- a/drivers/net/can/c_can/c_can.h
+++ b/drivers/net/can/c_can/c_can.h
@@ -235,9 +235,22 @@ static inline u8 c_can_get_tx_tail(const struct c_can_tx_ring *ring)
return ring->tail & (ring->obj_num - 1);
}
-static inline u8 c_can_get_tx_free(const struct c_can_tx_ring *ring)
+static inline u8 c_can_get_tx_free(const struct c_can_priv *priv,
+ const struct c_can_tx_ring *ring)
{
- return ring->obj_num - (ring->head - ring->tail);
+ u8 head = c_can_get_tx_head(ring);
+ u8 tail = c_can_get_tx_tail(ring);
+
+ if (priv->type == BOSCH_D_CAN)
+ return ring->obj_num - (ring->head - ring->tail);
+
+ /* This is not a FIFO. C/D_CAN sends out the buffers
+ * prioritized. The lowest buffer number wins.
+ */
+ if (head < tail)
+ return 0;
+
+ return ring->obj_num - head;
}
#endif /* C_CAN_H */
diff --git a/drivers/net/can/c_can/c_can_main.c b/drivers/net/can/c_can/c_can_main.c
index dc8132862f333a..d6605dbb7737bb 100644
--- a/drivers/net/can/c_can/c_can_main.c
+++ b/drivers/net/can/c_can/c_can_main.c
@@ -429,7 +429,7 @@ static void c_can_setup_receive_object(struct net_device *dev, int iface,
static bool c_can_tx_busy(const struct c_can_priv *priv,
const struct c_can_tx_ring *tx_ring)
{
- if (c_can_get_tx_free(tx_ring) > 0)
+ if (c_can_get_tx_free(priv, tx_ring) > 0)
return false;
netif_stop_queue(priv->dev);
@@ -437,7 +437,7 @@ static bool c_can_tx_busy(const struct c_can_priv *priv,
/* Memory barrier before checking tx_free (head and tail) */
smp_mb();
- if (c_can_get_tx_free(tx_ring) == 0) {
+ if (c_can_get_tx_free(priv, tx_ring) == 0) {
netdev_dbg(priv->dev,
"Stopping tx-queue (tx_head=0x%08x, tx_tail=0x%08x, len=%d).\n",
tx_ring->head, tx_ring->tail,
@@ -465,7 +465,7 @@ static netdev_tx_t c_can_start_xmit(struct sk_buff *skb,
idx = c_can_get_tx_head(tx_ring);
tx_ring->head++;
- if (c_can_get_tx_free(tx_ring) == 0)
+ if (c_can_get_tx_free(priv, tx_ring) == 0)
netif_stop_queue(dev);
if (idx < c_can_get_tx_tail(tx_ring))
@@ -748,7 +748,7 @@ static void c_can_do_tx(struct net_device *dev)
return;
tx_ring->tail += pkts;
- if (c_can_get_tx_free(tx_ring)) {
+ if (c_can_get_tx_free(priv, tx_ring)) {
/* Make sure that anybody stopping the queue after
* this sees the new tx_ring->tail.
*/
@@ -760,8 +760,7 @@ static void c_can_do_tx(struct net_device *dev)
stats->tx_packets += pkts;
tail = c_can_get_tx_tail(tx_ring);
-
- if (tail == 0) {
+ if (priv->type == BOSCH_D_CAN && tail == 0) {
u8 head = c_can_get_tx_head(tx_ring);
/* Start transmission for all cached messages */