6.6-stable review patch. If anyone has any objections, please let me know.
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From: Marc Kleine-Budde mkl@pengutronix.de
[ Upstream commit 50ea5449c56310d2d31c28ba91a59232116d3c1e ]
If the ring (rx, tx) and/or coalescing parameters (rx-frames-irq, tx-frames-irq) have been configured while the interface was in CAN-CC mode, but the interface is brought up in CAN-FD mode, the ring parameters might be too big.
Use the default CAN-FD values in this case.
Fixes: 9263c2e92be9 ("can: mcp251xfd: ring: add support for runtime configurable RX/TX ring parameters") Link: https://lore.kernel.org/all/20240805-mcp251xfd-fix-ringconfig-v1-1-72086f0ca... Signed-off-by: Marc Kleine-Budde mkl@pengutronix.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/can/spi/mcp251xfd/mcp251xfd-ram.c | 11 +++++++++- .../net/can/spi/mcp251xfd/mcp251xfd-ring.c | 20 ++++++++++++++++--- 2 files changed, 27 insertions(+), 4 deletions(-)
diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-ram.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-ram.c index 9e8e82cdba46..61b0d6fa52dd 100644 --- a/drivers/net/can/spi/mcp251xfd/mcp251xfd-ram.c +++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-ram.c @@ -97,7 +97,16 @@ void can_ram_get_layout(struct can_ram_layout *layout, if (ring) { u8 num_rx_coalesce = 0, num_tx_coalesce = 0;
- num_rx = can_ram_rounddown_pow_of_two(config, &config->rx, 0, ring->rx_pending); + /* If the ring parameters have been configured in + * CAN-CC mode, but and we are in CAN-FD mode now, + * they might be to big. Use the default CAN-FD values + * in this case. + */ + num_rx = ring->rx_pending; + if (num_rx > layout->max_rx) + num_rx = layout->default_rx; + + num_rx = can_ram_rounddown_pow_of_two(config, &config->rx, 0, num_rx);
/* The ethtool doc says: * To disable coalescing, set usecs = 0 and max_frames = 1. diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c index 4cb79a4f2461..3a941a71c78f 100644 --- a/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c +++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c @@ -468,11 +468,25 @@ int mcp251xfd_ring_alloc(struct mcp251xfd_priv *priv)
/* switching from CAN-2.0 to CAN-FD mode or vice versa */ if (fd_mode != test_bit(MCP251XFD_FLAGS_FD_MODE, priv->flags)) { + const struct ethtool_ringparam ring = { + .rx_pending = priv->rx_obj_num, + .tx_pending = priv->tx->obj_num, + }; + const struct ethtool_coalesce ec = { + .rx_coalesce_usecs_irq = priv->rx_coalesce_usecs_irq, + .rx_max_coalesced_frames_irq = priv->rx_obj_num_coalesce_irq, + .tx_coalesce_usecs_irq = priv->tx_coalesce_usecs_irq, + .tx_max_coalesced_frames_irq = priv->tx_obj_num_coalesce_irq, + }; struct can_ram_layout layout;
- can_ram_get_layout(&layout, &mcp251xfd_ram_config, NULL, NULL, fd_mode); - priv->rx_obj_num = layout.default_rx; - tx_ring->obj_num = layout.default_tx; + can_ram_get_layout(&layout, &mcp251xfd_ram_config, &ring, &ec, fd_mode); + + priv->rx_obj_num = layout.cur_rx; + priv->rx_obj_num_coalesce_irq = layout.rx_coalesce; + + tx_ring->obj_num = layout.cur_tx; + priv->tx_obj_num_coalesce_irq = layout.tx_coalesce; }
if (fd_mode) {