From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932831AbcFJL3R (ORCPT ); Fri, 10 Jun 2016 07:29:17 -0400 Received: from nbd.name ([46.4.11.11]:56262 "EHLO nbd.name" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932220AbcFJL2f (ORCPT ); Fri, 10 Jun 2016 07:28:35 -0400 From: John Crispin To: "David S. Miller" Cc: Felix Fietkau , Sean Wang , netdev@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, John Crispin Subject: [PATCH V2 09/11] net: mediatek: fix off by one in the TX ring allocation Date: Fri, 10 Jun 2016 13:28:06 +0200 Message-Id: <1465558088-15265-10-git-send-email-john@phrozen.org> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1465558088-15265-1-git-send-email-john@phrozen.org> References: <1465558088-15265-1-git-send-email-john@phrozen.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The TX ring setup has an off by one error causing it to not utilise all descriptors. This has the side effect that we need to reset the next pointer at runtime to make it work. Fix the off by one and remove the code fixing the ring at runtime. Signed-off-by: John Crispin --- drivers/net/ethernet/mediatek/mtk_eth_soc.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c index 24714ab..6daf48b 100644 --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c @@ -903,7 +903,6 @@ static int mtk_poll_tx(struct mtk_eth *eth, int budget, bool *tx_again) } mtk_tx_unmap(eth->dev, tx_buf); - ring->last_free->txd2 = next_cpu; ring->last_free = desc; atomic_inc(&ring->free_count); @@ -1011,7 +1010,7 @@ static int mtk_tx_alloc(struct mtk_eth *eth) atomic_set(&ring->free_count, MTK_DMA_SIZE - 2); ring->next_free = &ring->dma[0]; - ring->last_free = &ring->dma[MTK_DMA_SIZE - 2]; + ring->last_free = &ring->dma[MTK_DMA_SIZE - 1]; ring->thresh = MAX_SKB_FRAGS; /* make sure that all changes to the dma ring are flushed before we -- 1.7.10.4