diff options
| author | Marc Kleine-Budde <mkl@pengutronix.de> | 2013-10-04 10:52:36 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-11-13 12:01:48 +0900 |
| commit | f49c173bb693fa2aea6c96c931f9449ce4885d7b (patch) | |
| tree | 6614dba7f2bb2621417c10eda48e790e3eb376bb | |
| parent | 20b2a1eb2de54d0fce4dee198546cc448589dad8 (diff) | |
can: flexcan: flexcan_chip_start: fix regression, mark one MB for TX and abort pending TX
commit d5a7b406c529e4595ce03dc8f6dcf7fa36f106fa upstream.
In patch
0d1862e can: flexcan: fix flexcan_chip_start() on imx6
the loop in flexcan_chip_start() that iterates over all mailboxes after the
soft reset of the CAN core was removed. This loop put all mailboxes (even the
ones marked as reserved 1...7) into EMPTY/INACTIVE mode. On mailboxes 8...63,
this aborts any pending TX messages.
After a cold boot there is random garbage in the mailboxes, which leads to
spontaneous transmit of CAN frames during first activation. Further if the
interface was disabled with a pending message (usually due to an error
condition on the CAN bus), this message is retransmitted after enabling the
interface again.
This patch fixes the regression by:
1) Limiting the maximum number of used mailboxes to 8, 0...7 are used by the RX
FIFO, 8 is used by TX.
2) Marking the TX mailbox as EMPTY/INACTIVE, so that any pending TX of that
mailbox is aborted.
Cc: Lothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/net/can/flexcan.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c index 00baa7e094f4..e2131ca64a5f 100644 --- a/drivers/net/can/flexcan.c +++ b/drivers/net/can/flexcan.c @@ -60,7 +60,7 @@ #define FLEXCAN_MCR_BCC BIT(16) #define FLEXCAN_MCR_LPRIO_EN BIT(13) #define FLEXCAN_MCR_AEN BIT(12) -#define FLEXCAN_MCR_MAXMB(x) ((x) & 0xf) +#define FLEXCAN_MCR_MAXMB(x) ((x) & 0x1f) #define FLEXCAN_MCR_IDAM_A (0 << 8) #define FLEXCAN_MCR_IDAM_B (1 << 8) #define FLEXCAN_MCR_IDAM_C (2 << 8) @@ -701,9 +701,11 @@ static int flexcan_chip_start(struct net_device *dev) * */ reg_mcr = flexcan_read(®s->mcr); + reg_mcr &= ~FLEXCAN_MCR_MAXMB(0xff); reg_mcr |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_FEN | FLEXCAN_MCR_HALT | FLEXCAN_MCR_SUPV | FLEXCAN_MCR_WRN_EN | - FLEXCAN_MCR_IDAM_C | FLEXCAN_MCR_SRX_DIS; + FLEXCAN_MCR_IDAM_C | FLEXCAN_MCR_SRX_DIS | + FLEXCAN_MCR_MAXMB(FLEXCAN_TX_BUF_ID); netdev_dbg(dev, "%s: writing mcr=0x%08x", __func__, reg_mcr); flexcan_write(reg_mcr, ®s->mcr); @@ -744,6 +746,10 @@ static int flexcan_chip_start(struct net_device *dev) ®s->cantxfg[i].can_ctrl); } + /* Abort any pending TX, mark Mailbox as INACTIVE */ + flexcan_write(FLEXCAN_MB_CNT_CODE(0x4), + ®s->cantxfg[FLEXCAN_TX_BUF_ID].can_ctrl); + /* acceptance mask/acceptance code (accept everything) */ flexcan_write(0x0, ®s->rxgmask); flexcan_write(0x0, ®s->rx14mask); |