[PATCH 4/8] can: flexcan: correctly initialize mailboxes
From: Marc Kleine-Budde <mkl@pengutronix.de>
Date: 2014-09-18 10:40:58
Also in:
linux-can
Subsystem:
can network drivers, the rest · Maintainers:
Marc Kleine-Budde, Vincent Mailhol, Linus Torvalds
From: David Jander <redacted> Apparently mailboxes may contain random data at startup, causing some of them being prepared for message reception. This causes overruns being missed or even confusing the IRQ check for trasmitted messages, increasing the transmit counter instead of the error counter. This patch initializes all mailboxes after the FIFO as RX_INACTIVE. Signed-off-by: David Jander <redacted> Cc: linux-stable <redacted> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> --- drivers/net/can/flexcan.c | 7 +++++++ 1 file changed, 7 insertions(+)
diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
index 76dcbca..fc076952 100644
--- a/drivers/net/can/flexcan.c
+++ b/drivers/net/can/flexcan.c@@ -812,6 +812,7 @@ static int flexcan_chip_start(struct net_device *dev) struct flexcan_regs __iomem *regs = priv->base; int err; u32 reg_mcr, reg_ctrl; + int i; /* enable module */ err = flexcan_chip_enable(priv);
@@ -878,6 +879,12 @@ static int flexcan_chip_start(struct net_device *dev) netdev_dbg(dev, "%s: writing ctrl=0x%08x", __func__, reg_ctrl); flexcan_write(reg_ctrl, ®s->ctrl); + /* clear and invalidate all mailboxes first */ + for (i = FLEXCAN_TX_BUF_ID; i < ARRAY_SIZE(regs->cantxfg); i++) { + flexcan_write(FLEXCAN_MB_CODE_RX_INACTIVE, + ®s->cantxfg[i].can_ctrl); + } + /* mark TX mailbox as INACTIVE */ flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE, ®s->cantxfg[FLEXCAN_TX_BUF_ID].can_ctrl);
--
2.1.0