--- /dev/null
+// 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);
+ int err;
+
+ /* enable clock gate */
+ err = clk_prepare_enable(priv->clk);
+ if (err)
+ return err;
+
+ 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);
+
+ clk_disable_unprepare(priv->clk);
+
+ 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) {
+ napi_complete(&ch->napi);
+ 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 (pkts < budget) {
+ napi_complete(&ch->napi);
+ ltq_dma_enable_irq(&ch->dma);
+ }
+
+ return pkts;
+}
+
+static int 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,
+ .ndo_change_mtu = eth_change_mtu,
+};
+
+static irqreturn_t xrx200_dma_irq(int irq, void *ptr)
+{
+ struct xrx200_chan *ch = ptr;
+
+ ltq_dma_disable_irq(&ch->dma);
+ ltq_dma_ack_irq(&ch->dma);
+
+ napi_schedule(&ch->napi);
+
+ 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 (!priv->pmac_reg) {
+ dev_err(dev, "failed to request and remap io ranges\n");
+ return -ENOMEM;
+ }
+
+ priv->chan_rx.dma.irq = platform_get_irq_byname(pdev, "rx");
+ if (priv->chan_rx.dma.irq < 0) {
+ dev_err(dev, "failed to get RX IRQ, %i\n",
+ priv->chan_rx.dma.irq);
+ return -ENOENT;
+ }
+ priv->chan_tx.dma.irq = platform_get_irq_byname(pdev, "tx");
+ if (priv->chan_tx.dma.irq < 0) {
+ dev_err(dev, "failed to get TX IRQ, %i\n",
+ priv->chan_tx.dma.irq);
+ 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 (mac && is_valid_ether_addr(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;
+
+ /* 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_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_uninit_dma;
+ return err;
+
+err_uninit_dma:
+ xrx200_hw_cleanup(priv);
+
+ return 0;
+}
+
+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);
+
+ /* 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");
projects / mirror_ubuntu-eoan-kernel.git / commitdiff