// SPDX-License-Identifier: GPL-2.0 /* * Lantiq / Intel PMAC driver for XRX200 SoCs * * Copyright (C) 2010 Lantiq Deutschland * Copyright (C) 2012 John Crispin <john@phrozen.org> * Copyright (C) 2017 - 2018 Hauke Mehrtens <hauke@hauke-m.de> */ #include <linux/etherdevice.h> #include <linux/module.h> #include <linux/platform_device.h> #include <linux/interrupt.h> #include <linux/clk.h> #include <linux/delay.h> #include <linux/of_net.h> #include <linux/of_platform.h> #include <xway_dma.h> /* DMA */ #define XRX200_DMA_DATA_LEN 0x600 #define XRX200_DMA_RX 0 #define XRX200_DMA_TX 1 /* cpu port mac */ #define PMAC_RX_IPG 0x0024 #define PMAC_RX_IPG_MASK 0xf #define PMAC_HD_CTL 0x0000 /* Add Ethernet header to packets from DMA to PMAC */ #define PMAC_HD_CTL_ADD BIT(0) /* Add VLAN tag to Packets from DMA to PMAC */ #define PMAC_HD_CTL_TAG BIT(1) /* Add CRC to packets from DMA to PMAC */ #define PMAC_HD_CTL_AC BIT(2) /* Add status header to packets from PMAC to DMA */ #define PMAC_HD_CTL_AS BIT(3) /* Remove CRC from packets from PMAC to DMA */ #define PMAC_HD_CTL_RC BIT(4) /* Remove Layer-2 header from packets from PMAC to DMA */ #define PMAC_HD_CTL_RL2 BIT(5) /* Status header is present from DMA to PMAC */ #define PMAC_HD_CTL_RXSH BIT(6) /* Add special tag from PMAC to switch */ #define PMAC_HD_CTL_AST BIT(7) /* Remove specail Tag from PMAC to DMA */ #define PMAC_HD_CTL_RST BIT(8) /* Check CRC from DMA to PMAC */ #define PMAC_HD_CTL_CCRC BIT(9) /* Enable reaction to Pause frames in the PMAC */ #define PMAC_HD_CTL_FC BIT(10) struct xrx200_chan { int tx_free; struct napi_struct napi; struct ltq_dma_channel dma; struct sk_buff *skb[LTQ_DESC_NUM]; struct xrx200_priv *priv; }; struct xrx200_priv { struct clk *clk; struct xrx200_chan chan_tx; struct xrx200_chan chan_rx; struct net_device *net_dev; struct device *dev; __iomem void *pmac_reg; }; static u32 xrx200_pmac_r32(struct xrx200_priv *priv, u32 offset) { return __raw_readl(priv->pmac_reg + offset); } static void xrx200_pmac_w32(struct xrx200_priv *priv, u32 val, u32 offset) { __raw_writel(val, priv->pmac_reg + offset); } static void xrx200_pmac_mask(struct xrx200_priv *priv, u32 clear, u32 set, u32 offset) { u32 val = xrx200_pmac_r32(priv, offset); val &= ~(clear); val |= set; xrx200_pmac_w32(priv, val, offset); } /* drop all the packets from the DMA ring */ static void xrx200_flush_dma(struct xrx200_chan *ch) { int i; for (i = 0; i < LTQ_DESC_NUM; i++) { struct ltq_dma_desc *desc = &ch->dma.desc_base[ch->dma.desc]; if ((desc->ctl & (LTQ_DMA_OWN | LTQ_DMA_C)) != LTQ_DMA_C) break; desc->ctl = LTQ_DMA_OWN | LTQ_DMA_RX_OFFSET(NET_IP_ALIGN) | XRX200_DMA_DATA_LEN; ch->dma.desc++; ch->dma.desc %= LTQ_DESC_NUM; } } static int xrx200_open(struct net_device *net_dev) { struct xrx200_priv *priv = netdev_priv(net_dev); napi_enable(&priv->chan_tx.napi); ltq_dma_open(&priv->chan_tx.dma); ltq_dma_enable_irq(&priv->chan_tx.dma); napi_enable(&priv->chan_rx.napi); ltq_dma_open(&priv->chan_rx.dma); /* The boot loader does not always deactivate the receiving of frames * on the ports and then some packets queue up in the PPE buffers. * They already passed the PMAC so they do not have the tags * configured here. Read the these packets here and drop them. * The HW should have written them into memory after 10us */ usleep_range(20, 40); xrx200_flush_dma(&priv->chan_rx); ltq_dma_enable_irq(&priv->chan_rx.dma); netif_wake_queue(net_dev); return 0; } static int xrx200_close(struct net_device *net_dev) { struct xrx200_priv *priv = netdev_priv(net_dev); netif_stop_queue(net_dev); napi_disable(&priv->chan_rx.napi); ltq_dma_close(&priv->chan_rx.dma); napi_disable(&priv->chan_tx.napi); ltq_dma_close(&priv->chan_tx.dma); return 0; } static int xrx200_alloc_skb(struct xrx200_chan *ch) { int ret = 0; ch->skb[ch->dma.desc] = netdev_alloc_skb_ip_align(ch->priv->net_dev, XRX200_DMA_DATA_LEN); if (!ch->skb[ch->dma.desc]) { ret = -ENOMEM; goto skip; } ch->dma.desc_base[ch->dma.desc].addr = dma_map_single(ch->priv->dev, ch->skb[ch->dma.desc]->data, XRX200_DMA_DATA_LEN, DMA_FROM_DEVICE); if (unlikely(dma_mapping_error(ch->priv->dev, ch->dma.desc_base[ch->dma.desc].addr))) { dev_kfree_skb_any(ch->skb[ch->dma.desc]); ret = -ENOMEM; goto skip; } skip: ch->dma.desc_base[ch->dma.desc].ctl = LTQ_DMA_OWN | LTQ_DMA_RX_OFFSET(NET_IP_ALIGN) | XRX200_DMA_DATA_LEN; return ret; } static int xrx200_hw_receive(struct xrx200_chan *ch) { struct xrx200_priv *priv = ch->priv; struct ltq_dma_desc *desc = &ch->dma.desc_base[ch->dma.desc]; struct sk_buff *skb = ch->skb[ch->dma.desc]; int len = (desc->ctl & LTQ_DMA_SIZE_MASK); struct net_device *net_dev = priv->net_dev; int ret; ret = xrx200_alloc_skb(ch); ch->dma.desc++; ch->dma.desc %= LTQ_DESC_NUM; if (ret) { netdev_err(net_dev, "failed to allocate new rx buffer\n"); return ret; } skb_put(skb, len); skb->protocol = eth_type_trans(skb, net_dev); netif_receive_skb(skb); net_dev->stats.rx_packets++; net_dev->stats.rx_bytes += len - ETH_FCS_LEN; return 0; } static int xrx200_poll_rx(struct napi_struct *napi, int budget) { struct xrx200_chan *ch = container_of(napi, struct xrx200_chan, napi); int rx = 0; int ret; while (rx < budget) { struct ltq_dma_desc *desc = &ch->dma.desc_base[ch->dma.desc]; if ((desc->ctl & (LTQ_DMA_OWN | LTQ_DMA_C)) == LTQ_DMA_C) { ret = xrx200_hw_receive(ch); if (ret) return ret; rx++; } else { break; } } if (rx < budget) { if (napi_complete_done(&ch->napi, rx)) ltq_dma_enable_irq(&ch->dma); } return rx; } static int xrx200_tx_housekeeping(struct napi_struct *napi, int budget) { struct xrx200_chan *ch = container_of(napi, struct xrx200_chan, napi); struct net_device *net_dev = ch->priv->net_dev; int pkts = 0; int bytes = 0; while (pkts < budget) { struct ltq_dma_desc *desc = &ch->dma.desc_base[ch->tx_free]; if ((desc->ctl & (LTQ_DMA_OWN | LTQ_DMA_C)) == LTQ_DMA_C) { struct sk_buff *skb = ch->skb[ch->tx_free]; pkts++; bytes += skb->len; ch->skb[ch->tx_free] = NULL; consume_skb(skb); memset(&ch->dma.desc_base[ch->tx_free], 0, sizeof(struct ltq_dma_desc)); ch->tx_free++; ch->tx_free %= LTQ_DESC_NUM; } else { break; } } net_dev->stats.tx_packets += pkts; net_dev->stats.tx_bytes += bytes; netdev_completed_queue(ch->priv->net_dev, pkts, bytes); if (netif_queue_stopped(net_dev)) netif_wake_queue(net_dev); if (pkts < budget) { if (napi_complete_done(&ch->napi, pkts)) ltq_dma_enable_irq(&ch->dma); } return pkts; } static netdev_tx_t xrx200_start_xmit(struct sk_buff *skb, struct net_device *net_dev) { struct xrx200_priv *priv = netdev_priv(net_dev); struct xrx200_chan *ch = &priv->chan_tx; struct ltq_dma_desc *desc = &ch->dma.desc_base[ch->dma.desc]; u32 byte_offset; dma_addr_t mapping; int len; skb->dev = net_dev; if (skb_put_padto(skb, ETH_ZLEN)) { net_dev->stats.tx_dropped++; return NETDEV_TX_OK; } len = skb->len; if ((desc->ctl & (LTQ_DMA_OWN | LTQ_DMA_C)) || ch->skb[ch->dma.desc]) { netdev_err(net_dev, "tx ring full\n"); netif_stop_queue(net_dev); return NETDEV_TX_BUSY; } ch->skb[ch->dma.desc] = skb; mapping = dma_map_single(priv->dev, skb->data, len, DMA_TO_DEVICE); if (unlikely(dma_mapping_error(priv->dev, mapping))) goto err_drop; /* dma needs to start on a 16 byte aligned address */ byte_offset = mapping % 16; desc->addr = mapping - byte_offset; /* Make sure the address is written before we give it to HW */ wmb(); desc->ctl = LTQ_DMA_OWN | LTQ_DMA_SOP | LTQ_DMA_EOP | LTQ_DMA_TX_OFFSET(byte_offset) | (len & LTQ_DMA_SIZE_MASK); ch->dma.desc++; ch->dma.desc %= LTQ_DESC_NUM; if (ch->dma.desc == ch->tx_free) netif_stop_queue(net_dev); netdev_sent_queue(net_dev, len); return NETDEV_TX_OK; err_drop: dev_kfree_skb(skb); net_dev->stats.tx_dropped++; net_dev->stats.tx_errors++; return NETDEV_TX_OK; } static const struct net_device_ops xrx200_netdev_ops = { .ndo_open = xrx200_open, .ndo_stop = xrx200_close, .ndo_start_xmit = xrx200_start_xmit, .ndo_set_mac_address = eth_mac_addr, .ndo_validate_addr = eth_validate_addr, }; static irqreturn_t xrx200_dma_irq(int irq, void *ptr) { struct xrx200_chan *ch = ptr; if (napi_schedule_prep(&ch->napi)) { __napi_schedule(&ch->napi); ltq_dma_disable_irq(&ch->dma); } ltq_dma_ack_irq(&ch->dma); return IRQ_HANDLED; } static int xrx200_dma_init(struct xrx200_priv *priv) { struct xrx200_chan *ch_rx = &priv->chan_rx; struct xrx200_chan *ch_tx = &priv->chan_tx; int ret = 0; int i; ltq_dma_init_port(DMA_PORT_ETOP); ch_rx->dma.nr = XRX200_DMA_RX; ch_rx->dma.dev = priv->dev; ch_rx->priv = priv; ltq_dma_alloc_rx(&ch_rx->dma); for (ch_rx->dma.desc = 0; ch_rx->dma.desc < LTQ_DESC_NUM; ch_rx->dma.desc++) { ret = xrx200_alloc_skb(ch_rx); if (ret) goto rx_free; } ch_rx->dma.desc = 0; ret = devm_request_irq(priv->dev, ch_rx->dma.irq, xrx200_dma_irq, 0, "xrx200_net_rx", &priv->chan_rx); if (ret) { dev_err(priv->dev, "failed to request RX irq %d\n", ch_rx->dma.irq); goto rx_ring_free; } ch_tx->dma.nr = XRX200_DMA_TX; ch_tx->dma.dev = priv->dev; ch_tx->priv = priv; ltq_dma_alloc_tx(&ch_tx->dma); ret = devm_request_irq(priv->dev, ch_tx->dma.irq, xrx200_dma_irq, 0, "xrx200_net_tx", &priv->chan_tx); if (ret) { dev_err(priv->dev, "failed to request TX irq %d\n", ch_tx->dma.irq); goto tx_free; } return ret; tx_free: ltq_dma_free(&ch_tx->dma); rx_ring_free: /* free the allocated RX ring */ for (i = 0; i < LTQ_DESC_NUM; i++) { if (priv->chan_rx.skb[i]) dev_kfree_skb_any(priv->chan_rx.skb[i]); } rx_free: ltq_dma_free(&ch_rx->dma); return ret; } static void xrx200_hw_cleanup(struct xrx200_priv *priv) { int i; ltq_dma_free(&priv->chan_tx.dma); ltq_dma_free(&priv->chan_rx.dma); /* free the allocated RX ring */ for (i = 0; i < LTQ_DESC_NUM; i++) dev_kfree_skb_any(priv->chan_rx.skb[i]); } static int xrx200_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct device_node *np = dev->of_node; struct resource *res; struct xrx200_priv *priv; struct net_device *net_dev; const u8 *mac; int err; /* alloc the network device */ net_dev = devm_alloc_etherdev(dev, sizeof(struct xrx200_priv)); if (!net_dev) return -ENOMEM; priv = netdev_priv(net_dev); priv->net_dev = net_dev; priv->dev = dev; net_dev->netdev_ops = &xrx200_netdev_ops; SET_NETDEV_DEV(net_dev, dev); net_dev->min_mtu = ETH_ZLEN; net_dev->max_mtu = XRX200_DMA_DATA_LEN; /* load the memory ranges */ res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) { dev_err(dev, "failed to get resources\n"); return -ENOENT; } priv->pmac_reg = devm_ioremap_resource(dev, res); if (IS_ERR(priv->pmac_reg)) { dev_err(dev, "failed to request and remap io ranges\n"); return PTR_ERR(priv->pmac_reg); } priv->chan_rx.dma.irq = platform_get_irq_byname(pdev, "rx"); if (priv->chan_rx.dma.irq < 0) return -ENOENT; priv->chan_tx.dma.irq = platform_get_irq_byname(pdev, "tx"); if (priv->chan_tx.dma.irq < 0) return -ENOENT; /* get the clock */ priv->clk = devm_clk_get(dev, NULL); if (IS_ERR(priv->clk)) { dev_err(dev, "failed to get clock\n"); return PTR_ERR(priv->clk); } mac = of_get_mac_address(np); if (!IS_ERR(mac)) ether_addr_copy(net_dev->dev_addr, mac); else eth_hw_addr_random(net_dev); /* bring up the dma engine and IP core */ err = xrx200_dma_init(priv); if (err) return err; /* enable clock gate */ err = clk_prepare_enable(priv->clk); if (err) goto err_uninit_dma; /* set IPG to 12 */ xrx200_pmac_mask(priv, PMAC_RX_IPG_MASK, 0xb, PMAC_RX_IPG); /* enable status header, enable CRC */ xrx200_pmac_mask(priv, 0, PMAC_HD_CTL_RST | PMAC_HD_CTL_AST | PMAC_HD_CTL_RXSH | PMAC_HD_CTL_AS | PMAC_HD_CTL_AC | PMAC_HD_CTL_RC, PMAC_HD_CTL); /* setup NAPI */ netif_napi_add(net_dev, &priv->chan_rx.napi, xrx200_poll_rx, 32); netif_tx_napi_add(net_dev, &priv->chan_tx.napi, xrx200_tx_housekeeping, 32); platform_set_drvdata(pdev, priv); err = register_netdev(net_dev); if (err) goto err_unprepare_clk; return 0; err_unprepare_clk: clk_disable_unprepare(priv->clk); err_uninit_dma: xrx200_hw_cleanup(priv); return err; } static int xrx200_remove(struct platform_device *pdev) { struct xrx200_priv *priv = platform_get_drvdata(pdev); struct net_device *net_dev = priv->net_dev; /* free stack related instances */ netif_stop_queue(net_dev); netif_napi_del(&priv->chan_tx.napi); netif_napi_del(&priv->chan_rx.napi); /* remove the actual device */ unregister_netdev(net_dev); /* release the clock */ clk_disable_unprepare(priv->clk); /* shut down hardware */ xrx200_hw_cleanup(priv); return 0; } static const struct of_device_id xrx200_match[] = { { .compatible = "lantiq,xrx200-net" }, {}, }; MODULE_DEVICE_TABLE(of, xrx200_match); static struct platform_driver xrx200_driver = { .probe = xrx200_probe, .remove = xrx200_remove, .driver = { .name = "lantiq,xrx200-net", .of_match_table = xrx200_match, }, }; module_platform_driver(xrx200_driver); MODULE_AUTHOR("John Crispin <john@phrozen.org>"); MODULE_DESCRIPTION("Lantiq SoC XRX200 ethernet"); MODULE_LICENSE("GPL");