Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755503AbaK0JA7 (ORCPT ); Thu, 27 Nov 2014 04:00:59 -0500 Received: from mail.kernel.org ([198.145.19.201]:42303 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755091AbaK0Isr (ORCPT ); Thu, 27 Nov 2014 03:48:47 -0500 From: lizf@kernel.org To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, David Jander , Marc Kleine-Budde , Zefan Li Subject: [PATCH 3.4 55/91] can: flexcan: correctly initialize mailboxes Date: Thu, 27 Nov 2014 16:42:38 +0800 Message-Id: <1417077794-9299-55-git-send-email-lizf@kernel.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1417077368-9217-1-git-send-email-lizf@kernel.org> References: <1417077368-9217-1-git-send-email-lizf@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: David Jander 3.4.105-rc1 review patch. If anyone has any objections, please let me know. ------------------ 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: Zefan Li --- 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 062bbe2..1331558 100644 --- a/drivers/net/can/flexcan.c +++ b/drivers/net/can/flexcan.c @@ -680,6 +680,7 @@ 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 */ flexcan_chip_enable(priv); @@ -745,6 +746,12 @@ 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); -- 1.9.1 -- 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/