diff options
Diffstat (limited to 'drivers/net/ethernet/lantiq_xrx200.c')
-rw-r--r-- | drivers/net/ethernet/lantiq_xrx200.c | 685 |
1 files changed, 685 insertions, 0 deletions
diff --git a/drivers/net/ethernet/lantiq_xrx200.c b/drivers/net/ethernet/lantiq_xrx200.c new file mode 100644 index 000000000..8d646c7f8 --- /dev/null +++ b/drivers/net/ethernet/lantiq_xrx200.c @@ -0,0 +1,685 @@ +// 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/if_vlan.h> + +#include <linux/of_net.h> +#include <linux/of_platform.h> + +#include <xway_dma.h> + +/* DMA */ +#define XRX200_DMA_DATA_LEN (SZ_64K - 1) +#define XRX200_DMA_RX 0 +#define XRX200_DMA_TX 1 +#define XRX200_DMA_BURST_LEN 8 + +#define XRX200_DMA_PACKET_COMPLETE 0 +#define XRX200_DMA_PACKET_IN_PROGRESS 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; + + union { + struct sk_buff *skb[LTQ_DESC_NUM]; + void *rx_buff[LTQ_DESC_NUM]; + }; + + struct sk_buff *skb_head; + struct sk_buff *skb_tail; + + struct xrx200_priv *priv; +}; + +struct xrx200_priv { + struct clk *clk; + + struct xrx200_chan chan_tx; + struct xrx200_chan chan_rx; + + u16 rx_buf_size; + u16 rx_skb_size; + + 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); +} + +static int xrx200_max_frame_len(int mtu) +{ + return VLAN_ETH_HLEN + mtu; +} + +static int xrx200_buffer_size(int mtu) +{ + return round_up(xrx200_max_frame_len(mtu), 4 * XRX200_DMA_BURST_LEN); +} + +static int xrx200_skb_size(u16 buf_size) +{ + return SKB_DATA_ALIGN(buf_size + NET_SKB_PAD + NET_IP_ALIGN) + + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); +} + +/* 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) | + ch->priv->rx_buf_size; + 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_buf(struct xrx200_chan *ch, void *(*alloc)(unsigned int size)) +{ + void *buf = ch->rx_buff[ch->dma.desc]; + struct xrx200_priv *priv = ch->priv; + dma_addr_t mapping; + int ret = 0; + + ch->rx_buff[ch->dma.desc] = alloc(priv->rx_skb_size); + if (!ch->rx_buff[ch->dma.desc]) { + ch->rx_buff[ch->dma.desc] = buf; + ret = -ENOMEM; + goto skip; + } + + mapping = dma_map_single(priv->dev, ch->rx_buff[ch->dma.desc], + priv->rx_buf_size, DMA_FROM_DEVICE); + if (unlikely(dma_mapping_error(priv->dev, mapping))) { + skb_free_frag(ch->rx_buff[ch->dma.desc]); + ch->rx_buff[ch->dma.desc] = buf; + ret = -ENOMEM; + goto skip; + } + + ch->dma.desc_base[ch->dma.desc].addr = mapping + NET_SKB_PAD + NET_IP_ALIGN; + /* Make sure the address is written before we give it to HW */ + wmb(); +skip: + ch->dma.desc_base[ch->dma.desc].ctl = + LTQ_DMA_OWN | LTQ_DMA_RX_OFFSET(NET_IP_ALIGN) | priv->rx_buf_size; + + 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]; + void *buf = ch->rx_buff[ch->dma.desc]; + u32 ctl = desc->ctl; + int len = (ctl & LTQ_DMA_SIZE_MASK); + struct net_device *net_dev = priv->net_dev; + struct sk_buff *skb; + int ret; + + ret = xrx200_alloc_buf(ch, napi_alloc_frag); + + ch->dma.desc++; + ch->dma.desc %= LTQ_DESC_NUM; + + if (ret) { + net_dev->stats.rx_dropped++; + netdev_err(net_dev, "failed to allocate new rx buffer\n"); + return ret; + } + + skb = build_skb(buf, priv->rx_skb_size); + if (!skb) { + skb_free_frag(buf); + net_dev->stats.rx_dropped++; + return -ENOMEM; + } + + skb_reserve(skb, NET_SKB_PAD); + skb_put(skb, len); + + /* add buffers to skb via skb->frag_list */ + if (ctl & LTQ_DMA_SOP) { + ch->skb_head = skb; + ch->skb_tail = skb; + skb_reserve(skb, NET_IP_ALIGN); + } else if (ch->skb_head) { + if (ch->skb_head == ch->skb_tail) + skb_shinfo(ch->skb_tail)->frag_list = skb; + else + ch->skb_tail->next = skb; + ch->skb_tail = skb; + ch->skb_head->len += skb->len; + ch->skb_head->data_len += skb->len; + ch->skb_head->truesize += skb->truesize; + } + + if (ctl & LTQ_DMA_EOP) { + ch->skb_head->protocol = eth_type_trans(ch->skb_head, net_dev); + net_dev->stats.rx_packets++; + net_dev->stats.rx_bytes += ch->skb_head->len; + netif_receive_skb(ch->skb_head); + ch->skb_head = NULL; + ch->skb_tail = NULL; + ret = XRX200_DMA_PACKET_COMPLETE; + } else { + ret = XRX200_DMA_PACKET_IN_PROGRESS; + } + + return ret; +} + +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 == XRX200_DMA_PACKET_IN_PROGRESS) + continue; + if (ret != XRX200_DMA_PACKET_COMPLETE) + break; + 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; + + netif_tx_lock(net_dev); + 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); + + netif_tx_unlock(net_dev); + 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 burst length value aligned address */ + byte_offset = mapping % (XRX200_DMA_BURST_LEN * 4); + + 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 int +xrx200_change_mtu(struct net_device *net_dev, int new_mtu) +{ + struct xrx200_priv *priv = netdev_priv(net_dev); + struct xrx200_chan *ch_rx = &priv->chan_rx; + int old_mtu = net_dev->mtu; + bool running = false; + void *buff; + int curr_desc; + int ret = 0; + + net_dev->mtu = new_mtu; + priv->rx_buf_size = xrx200_buffer_size(new_mtu); + priv->rx_skb_size = xrx200_skb_size(priv->rx_buf_size); + + if (new_mtu <= old_mtu) + return ret; + + running = netif_running(net_dev); + if (running) { + napi_disable(&ch_rx->napi); + ltq_dma_close(&ch_rx->dma); + } + + xrx200_poll_rx(&ch_rx->napi, LTQ_DESC_NUM); + curr_desc = ch_rx->dma.desc; + + for (ch_rx->dma.desc = 0; ch_rx->dma.desc < LTQ_DESC_NUM; + ch_rx->dma.desc++) { + buff = ch_rx->rx_buff[ch_rx->dma.desc]; + ret = xrx200_alloc_buf(ch_rx, netdev_alloc_frag); + if (ret) { + net_dev->mtu = old_mtu; + priv->rx_buf_size = xrx200_buffer_size(old_mtu); + priv->rx_skb_size = xrx200_skb_size(priv->rx_buf_size); + break; + } + skb_free_frag(buff); + } + + ch_rx->dma.desc = curr_desc; + if (running) { + napi_enable(&ch_rx->napi); + ltq_dma_open(&ch_rx->dma); + ltq_dma_enable_irq(&ch_rx->dma); + } + + return ret; +} + +static const struct net_device_ops xrx200_netdev_ops = { + .ndo_open = xrx200_open, + .ndo_stop = xrx200_close, + .ndo_start_xmit = xrx200_start_xmit, + .ndo_change_mtu = xrx200_change_mtu, + .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)) { + ltq_dma_disable_irq(&ch->dma); + __napi_schedule(&ch->napi); + } + + 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, XRX200_DMA_BURST_LEN, + XRX200_DMA_BURST_LEN); + + 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_buf(ch_rx, netdev_alloc_frag); + 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]) + skb_free_frag(priv->chan_rx.rx_buff[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++) + skb_free_frag(priv->chan_rx.rx_buff[i]); +} + +static int xrx200_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; + struct xrx200_priv *priv; + struct net_device *net_dev; + 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 - xrx200_max_frame_len(0); + priv->rx_buf_size = xrx200_buffer_size(ETH_DATA_LEN); + priv->rx_skb_size = xrx200_skb_size(priv->rx_buf_size); + + /* load the memory ranges */ + priv->pmac_reg = devm_platform_get_and_ioremap_resource(pdev, 0, NULL); + if (IS_ERR(priv->pmac_reg)) + 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); + } + + err = of_get_ethdev_address(np, net_dev); + if (err) + 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); + netif_napi_add_tx(net_dev, &priv->chan_tx.napi, + xrx200_tx_housekeeping); + + 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"); |