This is a note to let you know that I've just added the patch titled
can: sun4i: handle overrun in RX FIFO
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
can-sun4i-handle-overrun-in-rx-fifo.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 4dcf924c2eda0c47a5c53b7703e3dc65ddaa8920 Mon Sep 17 00:00:00 2001
From: Gerhard Bertelsmann <info@xxxxxxxxxxxxxxxxxxxxxx>
Date: Mon, 6 Nov 2017 18:16:56 +0100
Subject: can: sun4i: handle overrun in RX FIFO
From: Gerhard Bertelsmann <info@xxxxxxxxxxxxxxxxxxxxxx>
commit 4dcf924c2eda0c47a5c53b7703e3dc65ddaa8920 upstream.
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@xxxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/can/sun4i_can.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
--- a/drivers/net/can/sun4i_can.c
+++ b/drivers/net/can/sun4i_can.c
@@ -539,6 +539,13 @@ static int sun4i_can_err(struct net_devi
}
stats->rx_over_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 */
sun4i_can_write_cmdreg(priv, SUN4I_CMD_CLEAR_OR_FLAG);
}
@@ -653,8 +660,9 @@ static irqreturn_t sun4i_can_interrupt(i
netif_wake_queue(dev);
can_led_event(dev, CAN_LED_EVENT_TX);
}
- if (isrc & SUN4I_INT_RBUF_VLD) {
- /* receive interrupt */
+ if ((isrc & SUN4I_INT_RBUF_VLD) &&
+ !(isrc & SUN4I_INT_DATA_OR)) {
+ /* receive interrupt - don't read if overrun occurred */
while (status & SUN4I_STA_RBUF_RDY) {
/* RX buffer is not empty */
sun4i_can_rx(dev);
Patches currently in stable-queue which might be from info@xxxxxxxxxxxxxxxxxxxxxx are
queue-4.4/can-sun4i-handle-overrun-in-rx-fifo.patch