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can: sun4i: handle overrun in RX FIFO

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SUN4Is CAN IP has a 64 byte deep FIFO buffer. If the buffer is not
drained fast enough (overrun) it's getting mangled. Already received
frames are dropped - the data can't be restored.

Signed-off-by: Gerhard Bertelsmann <info@gerhard-bertelsmann.de>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This commit is contained in:
Gerhard Bertelsmann
2017-11-06 18:16:56 +01:00
committed by Marc Kleine-Budde
parent fb5f0b3ef6
commit 4dcf924c2e
1 changed files with 10 additions and 2 deletions
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drivers/net/can/sun4i_can.c
+10 -2
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@@ -539,6 +539,13 @@ static int sun4i_can_err(struct net_device *dev, u8 isrc, u8 status)
} }
stats->rx_over_errors++; stats->rx_over_errors++;
stats->rx_errors++; stats->rx_errors++;
/* reset the CAN IP by entering reset mode
* ignoring timeout error
*/
set_reset_mode(dev);
set_normal_mode(dev);
/* clear bit */ /* clear bit */
sun4i_can_write_cmdreg(priv, SUN4I_CMD_CLEAR_OR_FLAG); sun4i_can_write_cmdreg(priv, SUN4I_CMD_CLEAR_OR_FLAG);
} }
@@ -653,8 +660,9 @@ static irqreturn_t sun4i_can_interrupt(int irq, void *dev_id)
netif_wake_queue(dev); netif_wake_queue(dev);
can_led_event(dev, CAN_LED_EVENT_TX); can_led_event(dev, CAN_LED_EVENT_TX);
} }
if (isrc & SUN4I_INT_RBUF_VLD) { if ((isrc & SUN4I_INT_RBUF_VLD) &&
/* receive interrupt */ !(isrc & SUN4I_INT_DATA_OR)) {
/* receive interrupt - don't read if overrun occurred */
while (status & SUN4I_STA_RBUF_RDY) { while (status & SUN4I_STA_RBUF_RDY) {
/* RX buffer is not empty */ /* RX buffer is not empty */
sun4i_can_rx(dev); sun4i_can_rx(dev);