1 files changed, 564 insertions, 0 deletions

diff --git a/drivers/net/ethernet/lantiq_xrx200.c b/drivers/net/ethernet/lantiq_xrx200.c
new file mode 100644
index 000000000000..c8b6d908f0cc
--- /dev/null
+++ b/drivers/net/ethernet/lantiq_xrx200.c
@@ -0,0 +1,564 @@
+// 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");