From patchwork Thu Jan 20 07:02:26 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Biao Huang X-Patchwork-Id: 533727 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 61130C4332F for ; Thu, 20 Jan 2022 07:03:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1358908AbiATHCw (ORCPT ); Thu, 20 Jan 2022 02:02:52 -0500 Received: from mailgw01.mediatek.com ([60.244.123.138]:60422 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1358879AbiATHCo (ORCPT ); Thu, 20 Jan 2022 02:02:44 -0500 X-UUID: a38643012e5d4eeb8e98916111748a21-20220120 X-UUID: a38643012e5d4eeb8e98916111748a21-20220120 Received: from mtkcas11.mediatek.inc [(172.21.101.40)] by mailgw01.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 765182154; Thu, 20 Jan 2022 15:02:41 +0800 Received: from mtkcas11.mediatek.inc (172.21.101.40) by mtkmbs10n1.mediatek.inc (172.21.101.34) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.2.792.15; Thu, 20 Jan 2022 15:02:39 +0800 Received: from localhost.localdomain (10.17.3.154) by mtkcas11.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Thu, 20 Jan 2022 15:02:38 +0800 From: Biao Huang To: David Miller , Rob Herring , Bartosz Golaszewski , Fabien Parent CC: Jakub Kicinski , Felix Fietkau , "John Crispin" , Sean Wang , Mark Lee , Matthias Brugger , , , , , , Biao Huang , Yinghua Pan , , Macpaul Lin Subject: [PATCH net-next v1 9/9] net: ethernet: mtk-star-emac: separate tx/rx handling with two NAPIs Date: Thu, 20 Jan 2022 15:02:26 +0800 Message-ID: <20220120070226.1492-10-biao.huang@mediatek.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220120070226.1492-1-biao.huang@mediatek.com> References: <20220120070226.1492-1-biao.huang@mediatek.com> MIME-Version: 1.0 X-MTK: N Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Current driver may lost tx interrupts under bidirectional test with iperf3, which leads to some unexpected issues. This patch let rx/tx interrupt enable/disable separately, and rx/tx are handled in different NAPIs. Signed-off-by: Biao Huang Signed-off-by: Yinghua Pan --- drivers/net/ethernet/mediatek/mtk_star_emac.c | 317 ++++++++++-------- 1 file changed, 181 insertions(+), 136 deletions(-) diff --git a/drivers/net/ethernet/mediatek/mtk_star_emac.c b/drivers/net/ethernet/mediatek/mtk_star_emac.c index 08a372848651..c46e05bfd8a5 100644 --- a/drivers/net/ethernet/mediatek/mtk_star_emac.c +++ b/drivers/net/ethernet/mediatek/mtk_star_emac.c @@ -229,7 +229,7 @@ struct mtk_star_ring_desc_data { struct sk_buff *skb; }; -#define MTK_STAR_RING_NUM_DESCS 128 +#define MTK_STAR_RING_NUM_DESCS 512 #define MTK_STAR_NUM_TX_DESCS MTK_STAR_RING_NUM_DESCS #define MTK_STAR_NUM_RX_DESCS MTK_STAR_RING_NUM_DESCS #define MTK_STAR_NUM_DESCS_TOTAL (MTK_STAR_RING_NUM_DESCS * 2) @@ -264,7 +264,8 @@ struct mtk_star_priv { struct mtk_star_ring rx_ring; struct mii_bus *mii; - struct napi_struct napi; + struct napi_struct tx_napi; + struct napi_struct rx_napi; struct device_node *phy_node; phy_interface_t phy_intf; @@ -380,19 +381,16 @@ mtk_star_ring_push_head_tx(struct mtk_star_ring *ring, mtk_star_ring_push_head(ring, desc_data, flags); } -static unsigned int mtk_star_ring_num_used_descs(struct mtk_star_ring *ring) +static unsigned int mtk_star_tx_ring_avail(struct mtk_star_ring *ring) { - return abs(ring->head - ring->tail); -} + u32 avail; -static bool mtk_star_ring_full(struct mtk_star_ring *ring) -{ - return mtk_star_ring_num_used_descs(ring) == MTK_STAR_RING_NUM_DESCS; -} + if (ring->tail > ring->head) + avail = ring->tail - ring->head - 1; + else + avail = MTK_STAR_RING_NUM_DESCS - ring->head + ring->tail - 1; -static bool mtk_star_ring_descs_available(struct mtk_star_ring *ring) -{ - return mtk_star_ring_num_used_descs(ring) > 0; + return avail; } static dma_addr_t mtk_star_dma_map_rx(struct mtk_star_priv *priv, @@ -415,7 +413,7 @@ static void mtk_star_dma_unmap_rx(struct mtk_star_priv *priv, } static dma_addr_t mtk_star_dma_map_tx(struct mtk_star_priv *priv, - struct sk_buff *skb) + struct sk_buff *skb) { struct device *dev = mtk_star_get_dev(priv); @@ -437,6 +435,36 @@ static void mtk_star_nic_disable_pd(struct mtk_star_priv *priv) MTK_STAR_BIT_MAC_CFG_NIC_PD); } +static void mtk_star_enable_dma_irq(struct mtk_star_priv *priv, + bool rx, bool tx) +{ + u32 value; + + regmap_read(priv->regs, MTK_STAR_REG_INT_MASK, &value); + + if (tx) + value &= ~MTK_STAR_BIT_INT_STS_TNTC; + if (rx) + value &= ~MTK_STAR_BIT_INT_STS_FNRC; + + regmap_write(priv->regs, MTK_STAR_REG_INT_MASK, value); +} + +static void mtk_star_disable_dma_irq(struct mtk_star_priv *priv, + bool rx, bool tx) +{ + u32 value; + + regmap_read(priv->regs, MTK_STAR_REG_INT_MASK, &value); + + if (tx) + value |= MTK_STAR_BIT_INT_STS_TNTC; + if (rx) + value |= MTK_STAR_BIT_INT_STS_FNRC; + + regmap_write(priv->regs, MTK_STAR_REG_INT_MASK, value); +} + /* Unmask the three interrupts we care about, mask all others. */ static void mtk_star_intr_enable(struct mtk_star_priv *priv) { @@ -452,20 +480,11 @@ static void mtk_star_intr_disable(struct mtk_star_priv *priv) regmap_write(priv->regs, MTK_STAR_REG_INT_MASK, ~0); } -static unsigned int mtk_star_intr_read(struct mtk_star_priv *priv) -{ - unsigned int val; - - regmap_read(priv->regs, MTK_STAR_REG_INT_STS, &val); - - return val; -} - static unsigned int mtk_star_intr_ack_all(struct mtk_star_priv *priv) { unsigned int val; - val = mtk_star_intr_read(priv); + regmap_read(priv->regs, MTK_STAR_REG_INT_STS, &val); regmap_write(priv->regs, MTK_STAR_REG_INT_STS, val); return val; @@ -737,25 +756,46 @@ static void mtk_star_free_tx_skbs(struct mtk_star_priv *priv) mtk_star_ring_free_skbs(priv, ring, mtk_star_dma_unmap_tx); } -/* All processing for TX and RX happens in the napi poll callback. - * - * FIXME: The interrupt handling should be more fine-grained with each - * interrupt enabled/disabled independently when needed. Unfortunatly this - * turned out to impact the driver's stability and until we have something - * working properly, we're disabling all interrupts during TX & RX processing - * or when resetting the counter registers. +/* mtk_star_handle_irq - Interrupt Handler. + * @irq: interrupt number. + * @data: pointer to a network interface device structure. + * Description : this is the driver interrupt service routine. + * it mainly handles: + * 1. tx complete interrupt for frame transmission. + * 2. rx complete interrupt for frame reception. + * 3. MAC Management Counter interrupt to avoid counter overflow. */ static irqreturn_t mtk_star_handle_irq(int irq, void *data) { - struct mtk_star_priv *priv; - struct net_device *ndev; + struct net_device *ndev = data; + struct mtk_star_priv *priv = netdev_priv(ndev); + unsigned int intr_status = mtk_star_intr_ack_all(priv); + unsigned long flags = 0; + + if (intr_status & MTK_STAR_BIT_INT_STS_FNRC) { + if (napi_schedule_prep(&priv->rx_napi)) { + spin_lock_irqsave(&priv->lock, flags); + /* mask Rx Complete interrupt */ + mtk_star_disable_dma_irq(priv, true, false); + spin_unlock_irqrestore(&priv->lock, flags); + __napi_schedule_irqoff(&priv->rx_napi); + } + } - ndev = data; - priv = netdev_priv(ndev); + if (intr_status & MTK_STAR_BIT_INT_STS_TNTC) { + if (napi_schedule_prep(&priv->tx_napi)) { + spin_lock_irqsave(&priv->lock, flags); + /* mask Tx Complete interrupt */ + mtk_star_disable_dma_irq(priv, false, true); + spin_unlock_irqrestore(&priv->lock, flags); + __napi_schedule_irqoff(&priv->tx_napi); + } + } - if (netif_running(ndev)) { - mtk_star_intr_disable(priv); - napi_schedule(&priv->napi); + /* interrupt is triggered once any counters reach 0x8000000 */ + if (intr_status & MTK_STAR_REG_INT_STS_MIB_CNT_TH) { + mtk_star_update_stats(priv); + mtk_star_reset_counters(priv); } return IRQ_HANDLED; @@ -971,7 +1011,8 @@ static int mtk_star_enable(struct net_device *ndev) if (ret) goto err_free_skbs; - napi_enable(&priv->napi); + napi_enable(&priv->tx_napi); + napi_enable(&priv->rx_napi); mtk_star_intr_ack_all(priv); mtk_star_intr_enable(priv); @@ -1004,7 +1045,8 @@ static void mtk_star_disable(struct net_device *ndev) struct mtk_star_priv *priv = netdev_priv(ndev); netif_stop_queue(ndev); - napi_disable(&priv->napi); + napi_disable(&priv->tx_napi); + napi_disable(&priv->rx_napi); mtk_star_intr_disable(priv); mtk_star_dma_disable(priv); mtk_star_intr_ack_all(priv); @@ -1043,6 +1085,17 @@ static int mtk_star_netdev_start_xmit(struct sk_buff *skb, struct mtk_star_ring *ring = &priv->tx_ring; struct device *dev = mtk_star_get_dev(priv); struct mtk_star_ring_desc_data desc_data; + int nfrags = skb_shinfo(skb)->nr_frags; + + if (unlikely(mtk_star_tx_ring_avail(ring) < nfrags + 1)) { + if (!netif_queue_stopped(ndev)) { + netif_stop_queue(ndev); + /* This is a hard error, log it. */ + netdev_err(priv->ndev, "%s: Tx Ring full when queue awake\n", + __func__); + } + return NETDEV_TX_BUSY; + } desc_data.dma_addr = mtk_star_dma_map_tx(priv, skb); if (dma_mapping_error(dev, desc_data.dma_addr)) @@ -1050,18 +1103,10 @@ static int mtk_star_netdev_start_xmit(struct sk_buff *skb, desc_data.skb = skb; desc_data.len = skb->len; - - spin_lock_bh(&priv->lock); - mtk_star_ring_push_head_tx(ring, &desc_data); netdev_sent_queue(ndev, skb->len); - if (mtk_star_ring_full(ring)) - netif_stop_queue(ndev); - - spin_unlock_bh(&priv->lock); - mtk_star_dma_resume_tx(priv); return NETDEV_TX_OK; @@ -1092,23 +1137,31 @@ static int mtk_star_tx_complete_one(struct mtk_star_priv *priv) return ret; } -static void mtk_star_tx_complete_all(struct mtk_star_priv *priv) +static int mtk_star_tx_poll(struct napi_struct *napi, int budget) { - struct mtk_star_ring *ring = &priv->tx_ring; - struct net_device *ndev = priv->ndev; - int ret, pkts_compl, bytes_compl; + int ret, pkts_compl = 0, bytes_compl = 0, count = 0; + struct mtk_star_priv *priv; + struct mtk_star_ring *ring; + struct net_device *ndev; + unsigned long flags = 0; + unsigned int entry; bool wake = false; - spin_lock(&priv->lock); + priv = container_of(napi, struct mtk_star_priv, tx_napi); + ndev = priv->ndev; - for (pkts_compl = 0, bytes_compl = 0;; + __netif_tx_lock_bh(netdev_get_tx_queue(priv->ndev, 0)); + ring = &priv->tx_ring; + entry = ring->tail; + for (pkts_compl = 0, bytes_compl = 0; + (entry != ring->head) && (count < budget); pkts_compl++, bytes_compl += ret, wake = true) { - if (!mtk_star_ring_descs_available(ring)) - break; ret = mtk_star_tx_complete_one(priv); if (ret < 0) break; + count++; + entry = ring->tail; } netdev_completed_queue(ndev, pkts_compl, bytes_compl); @@ -1116,7 +1169,16 @@ static void mtk_star_tx_complete_all(struct mtk_star_priv *priv) if (wake && netif_queue_stopped(ndev)) netif_wake_queue(ndev); - spin_unlock(&priv->lock); + __netif_tx_unlock_bh(netdev_get_tx_queue(priv->ndev, 0)); + + count = min(count, budget); + if (count < budget && napi_complete_done(napi, count)) { + spin_lock_irqsave(&priv->lock, flags); + mtk_star_enable_dma_irq(priv, false, true); + spin_unlock_irqrestore(&priv->lock, flags); + } + + return count; } static void mtk_star_netdev_get_stats64(struct net_device *ndev, @@ -1196,7 +1258,7 @@ static const struct ethtool_ops mtk_star_ethtool_ops = { .set_link_ksettings = phy_ethtool_set_link_ksettings, }; -static int mtk_star_receive_packet(struct mtk_star_priv *priv) +static int mtk_star_rx(struct mtk_star_priv *priv, int budget) { struct mtk_star_ring *ring = &priv->rx_ring; struct device *dev = mtk_star_get_dev(priv); @@ -1204,107 +1266,86 @@ static int mtk_star_receive_packet(struct mtk_star_priv *priv) struct net_device *ndev = priv->ndev; struct sk_buff *curr_skb, *new_skb; dma_addr_t new_dma_addr; - int ret; + int ret, count = 0; - spin_lock(&priv->lock); - ret = mtk_star_ring_pop_tail(ring, &desc_data); - spin_unlock(&priv->lock); - if (ret) - return -1; + while (count < budget) { + ret = mtk_star_ring_pop_tail(ring, &desc_data); + if (ret) + return -1; - curr_skb = desc_data.skb; + curr_skb = desc_data.skb; - if ((desc_data.flags & MTK_STAR_DESC_BIT_RX_CRCE) || - (desc_data.flags & MTK_STAR_DESC_BIT_RX_OSIZE)) { - /* Error packet -> drop and reuse skb. */ - new_skb = curr_skb; - goto push_new_skb; - } + if ((desc_data.flags & MTK_STAR_DESC_BIT_RX_CRCE) || + (desc_data.flags & MTK_STAR_DESC_BIT_RX_OSIZE)) { + /* Error packet -> drop and reuse skb. */ + new_skb = curr_skb; + goto push_new_skb; + } - /* Prepare new skb before receiving the current one. Reuse the current - * skb if we fail at any point. - */ - new_skb = mtk_star_alloc_skb(ndev); - if (!new_skb) { - ndev->stats.rx_dropped++; - new_skb = curr_skb; - goto push_new_skb; - } + /* Prepare new skb before receiving the current one. + * Reuse the current skb if we fail at any point. + */ + new_skb = mtk_star_alloc_skb(ndev); + if (!new_skb) { + ndev->stats.rx_dropped++; + new_skb = curr_skb; + goto push_new_skb; + } - new_dma_addr = mtk_star_dma_map_rx(priv, new_skb); - if (dma_mapping_error(dev, new_dma_addr)) { - ndev->stats.rx_dropped++; - dev_kfree_skb(new_skb); - new_skb = curr_skb; - netdev_err(ndev, "DMA mapping error of RX descriptor\n"); - goto push_new_skb; - } + new_dma_addr = mtk_star_dma_map_rx(priv, new_skb); + if (dma_mapping_error(dev, new_dma_addr)) { + ndev->stats.rx_dropped++; + dev_kfree_skb(new_skb); + new_skb = curr_skb; + netdev_err(ndev, "DMA mapping error of RX descriptor\n"); + goto push_new_skb; + } - /* We can't fail anymore at this point: it's safe to unmap the skb. */ - mtk_star_dma_unmap_rx(priv, &desc_data); + /* We can't fail anymore at this point: + * it's safe to unmap the skb. + */ + mtk_star_dma_unmap_rx(priv, &desc_data); - skb_put(desc_data.skb, desc_data.len); - desc_data.skb->ip_summed = CHECKSUM_NONE; - desc_data.skb->protocol = eth_type_trans(desc_data.skb, ndev); - desc_data.skb->dev = ndev; - netif_receive_skb(desc_data.skb); + skb_put(desc_data.skb, desc_data.len); + desc_data.skb->ip_summed = CHECKSUM_NONE; + desc_data.skb->protocol = eth_type_trans(desc_data.skb, ndev); + desc_data.skb->dev = ndev; + netif_receive_skb(desc_data.skb); - /* update dma_addr for new skb */ - desc_data.dma_addr = new_dma_addr; + /* update dma_addr for new skb */ + desc_data.dma_addr = new_dma_addr; push_new_skb: - desc_data.len = skb_tailroom(new_skb); - desc_data.skb = new_skb; - - spin_lock(&priv->lock); - mtk_star_ring_push_head_rx(ring, &desc_data); - spin_unlock(&priv->lock); - - return 0; -} -static int mtk_star_process_rx(struct mtk_star_priv *priv, int budget) -{ - int received, ret; + count++; - for (received = 0, ret = 0; received < budget && ret == 0; received++) - ret = mtk_star_receive_packet(priv); + desc_data.len = skb_tailroom(new_skb); + desc_data.skb = new_skb; + mtk_star_ring_push_head_rx(ring, &desc_data); + } mtk_star_dma_resume_rx(priv); - return received; + return count; } -static int mtk_star_poll(struct napi_struct *napi, int budget) +static int mtk_star_rx_poll(struct napi_struct *napi, int budget) { struct mtk_star_priv *priv; - unsigned int status; - int received = 0; + unsigned long flags = 0; + int work_done = 0; - priv = container_of(napi, struct mtk_star_priv, napi); + priv = container_of(napi, struct mtk_star_priv, rx_napi); - status = mtk_star_intr_read(priv); - mtk_star_intr_ack_all(priv); - - if (status & MTK_STAR_BIT_INT_STS_TNTC) - /* Clean-up all TX descriptors. */ - mtk_star_tx_complete_all(priv); - - if (status & MTK_STAR_BIT_INT_STS_FNRC) - /* Receive up to $budget packets. */ - received = mtk_star_process_rx(priv, budget); - - if (unlikely(status & MTK_STAR_REG_INT_STS_MIB_CNT_TH)) { - mtk_star_update_stats(priv); - mtk_star_reset_counters(priv); + work_done = mtk_star_rx(priv, budget); + if (work_done < budget) { + napi_complete_done(napi, work_done); + spin_lock_irqsave(&priv->lock, flags); + mtk_star_enable_dma_irq(priv, true, false); + spin_unlock_irqrestore(&priv->lock, flags); } - if (received < budget) - napi_complete_done(napi, received); - - mtk_star_intr_enable(priv); - - return received; + return work_done; } static void mtk_star_mdio_rwok_clear(struct mtk_star_priv *priv) @@ -1478,6 +1519,7 @@ static int mtk_star_set_timing(struct mtk_star_priv *priv) return 0; } + static int mtk_star_probe(struct platform_device *pdev) { struct device_node *of_node; @@ -1604,7 +1646,10 @@ static int mtk_star_probe(struct platform_device *pdev) ndev->netdev_ops = &mtk_star_netdev_ops; ndev->ethtool_ops = &mtk_star_ethtool_ops; - netif_napi_add(ndev, &priv->napi, mtk_star_poll, MTK_STAR_NAPI_WEIGHT); + netif_napi_add(ndev, &priv->rx_napi, + mtk_star_rx_poll, MTK_STAR_NAPI_WEIGHT); + netif_tx_napi_add(ndev, &priv->tx_napi, + mtk_star_tx_poll, MTK_STAR_NAPI_WEIGHT); return devm_register_netdev(dev, ndev); }