Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754250AbaKKLy0 (ORCPT ); Tue, 11 Nov 2014 06:54:26 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:57397 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753796AbaKKLJ7 (ORCPT ); Tue, 11 Nov 2014 06:09:59 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: David Jander , Marc Kleine-Budde , Luis Henriques Subject: [PATCH 3.16.y-ckt 061/170] can: flexcan: correctly initialize mailboxes Date: Tue, 11 Nov 2014 11:07:00 +0000 Message-Id: <1415704129-12709-62-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1415704129-12709-1-git-send-email-luis.henriques@canonical.com> References: <1415704129-12709-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.7-ckt1 -stable review patch. If anyone has any objections, please let me know. ------------------ From: David Jander commit fc05b884a31dbf259cc73cc856e634ec3acbebb6 upstream. 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 Signed-off-by: Marc Kleine-Budde Signed-off-by: Luis Henriques --- 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 f846bf63e347..0e06098ca05d 100644 --- a/drivers/net/can/flexcan.c +++ b/drivers/net/can/flexcan.c @@ -805,6 +805,7 @@ 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); @@ -869,6 +870,12 @@ 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 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/