From: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> [ Upstream commit ac2b81eb8b2d104033560daea886ee84531e3d0a ] When changing the interface from CAN-CC to CAN-FD mode the old coalescing parameters are re-used. This might cause problem, as the configured parameters are too big for CAN-FD mode. During testing an invalid TX coalescing configuration has been seen. The problem should be been fixed in the previous patch, but add a safeguard here to ensure that the number of TEF coalescing buffers (if configured) is exactly the half of all TEF buffers. Link: https://lore.kernel.org/all/20240805-mcp251xfd-fix-ringconfig-v1-2-72086f0ca5ee@xxxxxxxxxxxxxx Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c index 4cb79a4f2461..489d1439563a 100644 --- a/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c +++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c @@ -289,7 +289,7 @@ int mcp251xfd_ring_init(struct mcp251xfd_priv *priv) const struct mcp251xfd_rx_ring *rx_ring; u16 base = 0, ram_used; u8 fifo_nr = 1; - int i; + int err = 0, i; netdev_reset_queue(priv->ndev); @@ -385,10 +385,18 @@ int mcp251xfd_ring_init(struct mcp251xfd_priv *priv) netdev_err(priv->ndev, "Error during ring configuration, using more RAM (%u bytes) than available (%u bytes).\n", ram_used, MCP251XFD_RAM_SIZE); - return -ENOMEM; + err = -ENOMEM; } - return 0; + if (priv->tx_obj_num_coalesce_irq && + priv->tx_obj_num_coalesce_irq * 2 != priv->tx->obj_num) { + netdev_err(priv->ndev, + "Error during ring configuration, number of TEF coalescing buffers (%u) must be half of TEF buffers (%u).\n", + priv->tx_obj_num_coalesce_irq, priv->tx->obj_num); + err = -EINVAL; + } + + return err; } void mcp251xfd_ring_free(struct mcp251xfd_priv *priv) -- 2.43.0
