From patchwork Thu Mar 24 14:37:12 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Cyrille Pitchen X-Patchwork-Id: 8661361 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id D97A29F3D1 for ; Thu, 24 Mar 2016 14:39:04 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id EB8E8201FE for ; Thu, 24 Mar 2016 14:39:03 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1B2772017D for ; Thu, 24 Mar 2016 14:39:03 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1aj6Nm-0007qS-PC; Thu, 24 Mar 2016 14:37:06 +0000 Received: from eusmtp01.atmel.com ([212.144.249.243]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1aj6Ni-0007nR-8x for linux-arm-kernel@lists.infradead.org; Thu, 24 Mar 2016 14:37:03 +0000 Received: from tenerife.corp.atmel.com (10.161.101.13) by eusmtp01.atmel.com (10.161.101.31) with Microsoft SMTP Server id 14.3.235.1; Thu, 24 Mar 2016 15:36:32 +0100 From: Cyrille Pitchen To: , , , , , Subject: [PATCH 1/1] net: macb: remove BUG_ON() and reset the queue to handle RX errors Date: Thu, 24 Mar 2016 15:37:12 +0100 Message-ID: <1458830232-6159-1-git-send-email-cyrille.pitchen@atmel.com> X-Mailer: git-send-email 1.8.2.2 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160324_073702_740266_BB41F1B6 X-CRM114-Status: GOOD ( 14.71 ) X-Spam-Score: -4.2 (----) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Cyrille Pitchen , linux-kernel@vger.kernel.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch removes two BUG_ON() used to notify about RX queue corruptions on macb (not gem) hardware without actually handling the error. The new code skips corrupted frames but still processes faultless frames. Then it resets the RX queue before restarting the reception from a clean state. This patch is a rework of an older patch proposed by Neil Armstrong: http://patchwork.ozlabs.org/patch/371525/ Signed-off-by: Cyrille Pitchen Acked-by: Neil Armstrong Acked-by: Nicolas Ferre --- drivers/net/ethernet/cadence/macb.c | 59 ++++++++++++++++++++++++++++++------- 1 file changed, 49 insertions(+), 10 deletions(-) diff --git a/drivers/net/ethernet/cadence/macb.c b/drivers/net/ethernet/cadence/macb.c index 6619178ed77b..39447a337149 100644 --- a/drivers/net/ethernet/cadence/macb.c +++ b/drivers/net/ethernet/cadence/macb.c @@ -917,7 +917,10 @@ static int macb_rx_frame(struct macb *bp, unsigned int first_frag, unsigned int frag_len = bp->rx_buffer_size; if (offset + frag_len > len) { - BUG_ON(frag != last_frag); + if (unlikely(frag != last_frag)) { + dev_kfree_skb_any(skb); + return -1; + } frag_len = len - offset; } skb_copy_to_linear_data_offset(skb, offset, @@ -945,11 +948,26 @@ static int macb_rx_frame(struct macb *bp, unsigned int first_frag, return 0; } +static inline void macb_init_rx_ring(struct macb *bp) +{ + int i; + dma_addr_t addr; + + addr = bp->rx_buffers_dma; + for (i = 0; i < RX_RING_SIZE; i++) { + bp->rx_ring[i].addr = addr; + bp->rx_ring[i].ctrl = 0; + addr += bp->rx_buffer_size; + } + bp->rx_ring[RX_RING_SIZE - 1].addr |= MACB_BIT(RX_WRAP); +} + static int macb_rx(struct macb *bp, int budget) { int received = 0; unsigned int tail; int first_frag = -1; + int reset_rx_queue = 0; for (tail = bp->rx_tail; budget > 0; tail++) { struct macb_dma_desc *desc = macb_rx_desc(bp, tail); @@ -972,10 +990,18 @@ static int macb_rx(struct macb *bp, int budget) if (ctrl & MACB_BIT(RX_EOF)) { int dropped; - BUG_ON(first_frag == -1); + + if (unlikely(first_frag == -1)) { + reset_rx_queue = 1; + continue; + } dropped = macb_rx_frame(bp, first_frag, tail); first_frag = -1; + if (unlikely(dropped < 0)) { + reset_rx_queue = 1; + continue; + } if (!dropped) { received++; budget--; @@ -983,6 +1009,26 @@ static int macb_rx(struct macb *bp, int budget) } } + if (unlikely(reset_rx_queue)) { + unsigned long flags; + u32 ctrl; + + netdev_err(bp->dev, "RX queue corruption: reset it\n"); + + spin_lock_irqsave(&bp->lock, flags); + + ctrl = macb_readl(bp, NCR); + macb_writel(bp, NCR, ctrl & ~MACB_BIT(RE)); + + macb_init_rx_ring(bp); + macb_writel(bp, RBQP, bp->rx_ring_dma); + + macb_writel(bp, NCR, ctrl | MACB_BIT(RE)); + + spin_unlock_irqrestore(&bp->lock, flags); + return received; + } + if (first_frag != -1) bp->rx_tail = first_frag; else @@ -1523,15 +1569,8 @@ static void gem_init_rings(struct macb *bp) static void macb_init_rings(struct macb *bp) { int i; - dma_addr_t addr; - addr = bp->rx_buffers_dma; - for (i = 0; i < RX_RING_SIZE; i++) { - bp->rx_ring[i].addr = addr; - bp->rx_ring[i].ctrl = 0; - addr += bp->rx_buffer_size; - } - bp->rx_ring[RX_RING_SIZE - 1].addr |= MACB_BIT(RX_WRAP); + macb_init_rx_ring(bp); for (i = 0; i < TX_RING_SIZE; i++) { bp->queues[0].tx_ring[i].addr = 0;