net: add support for bcm6368-enet

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
diff --git a/drivers/net/bcm6368-eth.c b/drivers/net/bcm6368-eth.c
new file mode 100644
index 0000000..a31efba
--- /dev/null
+++ b/drivers/net/bcm6368-eth.c
@@ -0,0 +1,625 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2018 Álvaro Fernández Rojas <noltari@gmail.com>
+ *
+ * Derived from linux/drivers/net/ethernet/broadcom/bcm63xx_enet.c:
+ *	Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
+ */
+
+#include <common.h>
+#include <clk.h>
+#include <dm.h>
+#include <dma.h>
+#include <miiphy.h>
+#include <net.h>
+#include <reset.h>
+#include <wait_bit.h>
+#include <asm/io.h>
+
+#define ETH_PORT_STR			"brcm,enetsw-port"
+
+#define ETH_RX_DESC			PKTBUFSRX
+#define ETH_ZLEN			60
+#define ETH_TIMEOUT			100
+
+#define ETH_MAX_PORT			8
+#define ETH_RGMII_PORT0			4
+
+/* Port traffic control */
+#define ETH_PTCTRL_REG(x)		(0x0 + (x))
+#define ETH_PTCTRL_RXDIS_SHIFT		0
+#define ETH_PTCTRL_RXDIS_MASK		(1 << ETH_PTCTRL_RXDIS_SHIFT)
+#define ETH_PTCTRL_TXDIS_SHIFT		1
+#define ETH_PTCTRL_TXDIS_MASK		(1 << ETH_PTCTRL_TXDIS_SHIFT)
+
+/* Switch mode register */
+#define ETH_SWMODE_REG			0xb
+#define ETH_SWMODE_FWD_EN_SHIFT		1
+#define ETH_SWMODE_FWD_EN_MASK		(1 << ETH_SWMODE_FWD_EN_SHIFT)
+
+/* IMP override Register */
+#define ETH_IMPOV_REG			0xe
+#define ETH_IMPOV_LINKUP_SHIFT		0
+#define ETH_IMPOV_LINKUP_MASK		(1 << ETH_IMPOV_LINKUP_SHIFT)
+#define ETH_IMPOV_FDX_SHIFT		1
+#define ETH_IMPOV_FDX_MASK		(1 << ETH_IMPOV_FDX_SHIFT)
+#define ETH_IMPOV_100_SHIFT		2
+#define ETH_IMPOV_100_MASK		(1 << ETH_IMPOV_100_SHIFT)
+#define ETH_IMPOV_1000_SHIFT		3
+#define ETH_IMPOV_1000_MASK		(1 << ETH_IMPOV_1000_SHIFT)
+#define ETH_IMPOV_RXFLOW_SHIFT		4
+#define ETH_IMPOV_RXFLOW_MASK		(1 << ETH_IMPOV_RXFLOW_SHIFT)
+#define ETH_IMPOV_TXFLOW_SHIFT		5
+#define ETH_IMPOV_TXFLOW_MASK		(1 << ETH_IMPOV_TXFLOW_SHIFT)
+#define ETH_IMPOV_FORCE_SHIFT		7
+#define ETH_IMPOV_FORCE_MASK		(1 << ETH_IMPOV_FORCE_SHIFT)
+
+/* Port override Register */
+#define ETH_PORTOV_REG(x)		(0x58 + (x))
+#define ETH_PORTOV_LINKUP_SHIFT		0
+#define ETH_PORTOV_LINKUP_MASK		(1 << ETH_PORTOV_LINKUP_SHIFT)
+#define ETH_PORTOV_FDX_SHIFT		1
+#define ETH_PORTOV_FDX_MASK		(1 << ETH_PORTOV_FDX_SHIFT)
+#define ETH_PORTOV_100_SHIFT		2
+#define ETH_PORTOV_100_MASK		(1 << ETH_PORTOV_100_SHIFT)
+#define ETH_PORTOV_1000_SHIFT		3
+#define ETH_PORTOV_1000_MASK		(1 << ETH_PORTOV_1000_SHIFT)
+#define ETH_PORTOV_RXFLOW_SHIFT		4
+#define ETH_PORTOV_RXFLOW_MASK		(1 << ETH_PORTOV_RXFLOW_SHIFT)
+#define ETH_PORTOV_TXFLOW_SHIFT		5
+#define ETH_PORTOV_TXFLOW_MASK		(1 << ETH_PORTOV_TXFLOW_SHIFT)
+#define ETH_PORTOV_ENABLE_SHIFT		6
+#define ETH_PORTOV_ENABLE_MASK		(1 << ETH_PORTOV_ENABLE_SHIFT)
+
+/* Port RGMII control register */
+#define ETH_RGMII_CTRL_REG(x)		(0x60 + (x))
+#define ETH_RGMII_CTRL_GMII_CLK_EN	(1 << 7)
+#define ETH_RGMII_CTRL_MII_OVERRIDE_EN	(1 << 6)
+#define ETH_RGMII_CTRL_MII_MODE_MASK	(3 << 4)
+#define ETH_RGMII_CTRL_RGMII_MODE	(0 << 4)
+#define ETH_RGMII_CTRL_MII_MODE		(1 << 4)
+#define ETH_RGMII_CTRL_RVMII_MODE	(2 << 4)
+#define ETH_RGMII_CTRL_TIMING_SEL_EN	(1 << 0)
+
+/* Port RGMII timing register */
+#define ENETSW_RGMII_TIMING_REG(x)	(0x68 + (x))
+
+/* MDIO control register */
+#define MII_SC_REG			0xb0
+#define MII_SC_EXT_SHIFT		16
+#define MII_SC_EXT_MASK			(1 << MII_SC_EXT_SHIFT)
+#define MII_SC_REG_SHIFT		20
+#define MII_SC_PHYID_SHIFT		25
+#define MII_SC_RD_SHIFT			30
+#define MII_SC_RD_MASK			(1 << MII_SC_RD_SHIFT)
+#define MII_SC_WR_SHIFT			31
+#define MII_SC_WR_MASK			(1 << MII_SC_WR_SHIFT)
+
+/* MDIO data register */
+#define MII_DAT_REG			0xb4
+
+/* Global Management Configuration Register */
+#define ETH_GMCR_REG			0x200
+#define ETH_GMCR_RST_MIB_SHIFT		0
+#define ETH_GMCR_RST_MIB_MASK		(1 << ETH_GMCR_RST_MIB_SHIFT)
+
+/* Jumbo control register port mask register */
+#define ETH_JMBCTL_PORT_REG		0x4004
+
+/* Jumbo control mib good frame register */
+#define ETH_JMBCTL_MAXSIZE_REG		0x4008
+
+/* ETH port data */
+struct bcm_enetsw_port {
+	bool used;
+	const char *name;
+	/* Config */
+	bool bypass_link;
+	int force_speed;
+	bool force_duplex_full;
+	/* PHY */
+	int phy_id;
+};
+
+/* ETH data */
+struct bcm6368_eth_priv {
+	void __iomem *base;
+	/* DMA */
+	struct dma rx_dma;
+	struct dma tx_dma;
+	/* Ports */
+	uint8_t num_ports;
+	struct bcm_enetsw_port used_ports[ETH_MAX_PORT];
+	int sw_port_link[ETH_MAX_PORT];
+	bool rgmii_override;
+	bool rgmii_timing;
+	/* PHY */
+	int phy_id;
+};
+
+static inline bool bcm_enet_port_is_rgmii(int portid)
+{
+	return portid >= ETH_RGMII_PORT0;
+}
+
+static int bcm6368_mdio_read(struct bcm6368_eth_priv *priv, uint8_t ext,
+			     int phy_id, int reg)
+{
+	uint32_t val;
+
+	writel_be(0, priv->base + MII_SC_REG);
+
+	val = MII_SC_RD_MASK |
+	      (phy_id << MII_SC_PHYID_SHIFT) |
+	      (reg << MII_SC_REG_SHIFT);
+
+	if (ext)
+		val |= MII_SC_EXT_MASK;
+
+	writel_be(val, priv->base + MII_SC_REG);
+	udelay(50);
+
+	return readw_be(priv->base + MII_DAT_REG);
+}
+
+static int bcm6368_mdio_write(struct bcm6368_eth_priv *priv, uint8_t ext,
+			      int phy_id, int reg, u16 data)
+{
+	uint32_t val;
+
+	writel_be(0, priv->base + MII_SC_REG);
+
+	val = MII_SC_WR_MASK |
+	      (phy_id << MII_SC_PHYID_SHIFT) |
+	      (reg << MII_SC_REG_SHIFT);
+
+	if (ext)
+		val |= MII_SC_EXT_MASK;
+
+	val |= data;
+
+	writel_be(val, priv->base + MII_SC_REG);
+	udelay(50);
+
+	return 0;
+}
+
+static int bcm6368_eth_free_pkt(struct udevice *dev, uchar *packet, int len)
+{
+	struct bcm6368_eth_priv *priv = dev_get_priv(dev);
+
+	return dma_prepare_rcv_buf(&priv->rx_dma, packet, len);
+}
+
+static int bcm6368_eth_recv(struct udevice *dev, int flags, uchar **packetp)
+{
+	struct bcm6368_eth_priv *priv = dev_get_priv(dev);
+
+	return dma_receive(&priv->rx_dma, (void**)packetp, NULL);
+}
+
+static int bcm6368_eth_send(struct udevice *dev, void *packet, int length)
+{
+	struct bcm6368_eth_priv *priv = dev_get_priv(dev);
+
+	/* pad packets smaller than ETH_ZLEN */
+	if (length < ETH_ZLEN) {
+		memset(packet + length, 0, ETH_ZLEN - length);
+		length = ETH_ZLEN;
+	}
+
+	return dma_send(&priv->tx_dma, packet, length, NULL);
+}
+
+static int bcm6368_eth_adjust_link(struct udevice *dev)
+{
+	struct bcm6368_eth_priv *priv = dev_get_priv(dev);
+	unsigned int i;
+
+	for (i = 0; i < priv->num_ports; i++) {
+		struct bcm_enetsw_port *port;
+		int val, j, up, adv, lpa, speed, duplex, media;
+		int external_phy = bcm_enet_port_is_rgmii(i);
+		u8 override;
+
+		port = &priv->used_ports[i];
+		if (!port->used)
+			continue;
+
+		if (port->bypass_link)
+			continue;
+
+		/* dummy read to clear */
+		for (j = 0; j < 2; j++)
+			val = bcm6368_mdio_read(priv, external_phy,
+						port->phy_id, MII_BMSR);
+
+		if (val == 0xffff)
+			continue;
+
+		up = (val & BMSR_LSTATUS) ? 1 : 0;
+		if (!(up ^ priv->sw_port_link[i]))
+			continue;
+
+		priv->sw_port_link[i] = up;
+
+		/* link changed */
+		if (!up) {
+			dev_info(&priv->pdev->dev, "link DOWN on %s\n",
+				 port->name);
+			writeb_be(ETH_PORTOV_ENABLE_MASK,
+				  priv->base + ETH_PORTOV_REG(i));
+			writeb_be(ETH_PTCTRL_RXDIS_MASK |
+				  ETH_PTCTRL_TXDIS_MASK,
+				  priv->base + ETH_PTCTRL_REG(i));
+			continue;
+		}
+
+		adv = bcm6368_mdio_read(priv, external_phy,
+					port->phy_id, MII_ADVERTISE);
+
+		lpa = bcm6368_mdio_read(priv, external_phy, port->phy_id,
+					MII_LPA);
+
+		/* figure out media and duplex from advertise and LPA values */
+		media = mii_nway_result(lpa & adv);
+		duplex = (media & ADVERTISE_FULL) ? 1 : 0;
+
+		if (media & (ADVERTISE_100FULL | ADVERTISE_100HALF))
+			speed = 100;
+		else
+			speed = 10;
+
+		if (val & BMSR_ESTATEN) {
+			adv = bcm6368_mdio_read(priv, external_phy,
+						port->phy_id, MII_CTRL1000);
+
+			lpa = bcm6368_mdio_read(priv, external_phy,
+						port->phy_id, MII_STAT1000);
+
+			if ((adv & (ADVERTISE_1000FULL | ADVERTISE_1000HALF)) &&
+			    (lpa & (LPA_1000FULL | LPA_1000HALF))) {
+				speed = 1000;
+				duplex = (lpa & LPA_1000FULL);
+			}
+		}
+
+		pr_alert("link UP on %s, %dMbps, %s-duplex\n",
+			 port->name, speed, duplex ? "full" : "half");
+
+		override = ETH_PORTOV_ENABLE_MASK |
+			   ETH_PORTOV_LINKUP_MASK;
+
+		if (speed == 1000)
+			override |= ETH_PORTOV_1000_MASK;
+		else if (speed == 100)
+			override |= ETH_PORTOV_100_MASK;
+		if (duplex)
+			override |= ETH_PORTOV_FDX_MASK;
+
+		writeb_be(override, priv->base + ETH_PORTOV_REG(i));
+		writeb_be(0, priv->base + ETH_PTCTRL_REG(i));
+	}
+
+	return 0;
+}
+
+static int bcm6368_eth_start(struct udevice *dev)
+{
+	struct bcm6368_eth_priv *priv = dev_get_priv(dev);
+	uint8_t i;
+
+	/* prepare rx dma buffers */
+	for (i = 0; i < ETH_RX_DESC; i++) {
+		int ret = dma_prepare_rcv_buf(&priv->rx_dma, net_rx_packets[i],
+					      PKTSIZE_ALIGN);
+		if (ret < 0)
+			break;
+	}
+
+	/* enable dma rx channel */
+	dma_enable(&priv->rx_dma);
+
+	/* enable dma tx channel */
+	dma_enable(&priv->tx_dma);
+
+	/* apply override config for bypass_link ports here. */
+	for (i = 0; i < priv->num_ports; i++) {
+		struct bcm_enetsw_port *port;
+		u8 override;
+
+		port = &priv->used_ports[i];
+		if (!port->used)
+			continue;
+
+		if (!port->bypass_link)
+			continue;
+
+		override = ETH_PORTOV_ENABLE_MASK |
+			   ETH_PORTOV_LINKUP_MASK;
+
+		switch (port->force_speed) {
+		case 1000:
+			override |= ETH_PORTOV_1000_MASK;
+			break;
+		case 100:
+			override |= ETH_PORTOV_100_MASK;
+			break;
+		case 10:
+			break;
+		default:
+			pr_warn("%s: invalid forced speed on port %s\n",
+				__func__, port->name);
+			break;
+		}
+
+		if (port->force_duplex_full)
+			override |= ETH_PORTOV_FDX_MASK;
+
+		writeb_be(override, priv->base + ETH_PORTOV_REG(i));
+		writeb_be(0, priv->base + ETH_PTCTRL_REG(i));
+	}
+
+	bcm6368_eth_adjust_link(dev);
+
+	return 0;
+}
+
+static void bcm6368_eth_stop(struct udevice *dev)
+{
+	struct bcm6368_eth_priv *priv = dev_get_priv(dev);
+
+	/* disable dma rx channel */
+	dma_disable(&priv->rx_dma);
+
+	/* disable dma tx channel */
+	dma_disable(&priv->tx_dma);
+}
+
+static const struct eth_ops bcm6368_eth_ops = {
+	.free_pkt = bcm6368_eth_free_pkt,
+	.recv = bcm6368_eth_recv,
+	.send = bcm6368_eth_send,
+	.start = bcm6368_eth_start,
+	.stop = bcm6368_eth_stop,
+};
+
+static const struct udevice_id bcm6368_eth_ids[] = {
+	{ .compatible = "brcm,bcm6368-enet", },
+	{ /* sentinel */ }
+};
+
+static bool bcm6368_phy_is_external(struct bcm6368_eth_priv *priv, int phy_id)
+{
+	uint8_t i;
+
+	for (i = 0; i < priv->num_ports; ++i) {
+		if (!priv->used_ports[i].used)
+			continue;
+		if (priv->used_ports[i].phy_id == phy_id)
+			return bcm_enet_port_is_rgmii(i);
+	}
+
+	return true;
+}
+
+static int bcm6368_mii_mdio_read(struct mii_dev *bus, int addr, int devaddr,
+				 int reg)
+{
+	struct bcm6368_eth_priv *priv = bus->priv;
+	bool ext = bcm6368_phy_is_external(priv, addr);
+
+	return bcm6368_mdio_read(priv, ext, addr, reg);
+}
+
+static int bcm6368_mii_mdio_write(struct mii_dev *bus, int addr, int devaddr,
+				  int reg, u16 data)
+{
+	struct bcm6368_eth_priv *priv = bus->priv;
+	bool ext = bcm6368_phy_is_external(priv, addr);
+
+	return bcm6368_mdio_write(priv, ext, addr, reg, data);
+}
+
+static int bcm6368_mdio_init(const char *name, struct bcm6368_eth_priv *priv)
+{
+	struct mii_dev *bus;
+
+	bus = mdio_alloc();
+	if (!bus) {
+		pr_err("%s: failed to allocate MDIO bus\n", __func__);
+		return -ENOMEM;
+	}
+
+	bus->read = bcm6368_mii_mdio_read;
+	bus->write = bcm6368_mii_mdio_write;
+	bus->priv = priv;
+	snprintf(bus->name, sizeof(bus->name), "%s", name);
+
+	return mdio_register(bus);
+}
+
+static int bcm6368_eth_probe(struct udevice *dev)
+{
+	struct eth_pdata *pdata = dev_get_platdata(dev);
+	struct bcm6368_eth_priv *priv = dev_get_priv(dev);
+	int num_ports, ret, i;
+	uint32_t val;
+	ofnode node;
+
+	/* get base address */
+	priv->base = dev_remap_addr(dev);
+	if (!priv->base)
+		return -EINVAL;
+	pdata->iobase = (phys_addr_t) priv->base;
+
+	/* get number of ports */
+	num_ports = dev_read_u32_default(dev, "brcm,num-ports", ETH_MAX_PORT);
+	if (!num_ports || num_ports > ETH_MAX_PORT)
+		return -EINVAL;
+
+	/* get dma channels */
+	ret = dma_get_by_name(dev, "tx", &priv->tx_dma);
+	if (ret)
+		return -EINVAL;
+
+	ret = dma_get_by_name(dev, "rx", &priv->rx_dma);
+	if (ret)
+		return -EINVAL;
+
+	/* try to enable clocks */
+	for (i = 0; ; i++) {
+		struct clk clk;
+		int ret;
+
+		ret = clk_get_by_index(dev, i, &clk);
+		if (ret < 0)
+			break;
+
+		ret = clk_enable(&clk);
+		if (ret < 0) {
+			pr_err("%s: error enabling clock %d\n", __func__, i);
+			return ret;
+		}
+
+		ret = clk_free(&clk);
+		if (ret < 0) {
+			pr_err("%s: error freeing clock %d\n", __func__, i);
+			return ret;
+		}
+	}
+
+	/* try to perform resets */
+	for (i = 0; ; i++) {
+		struct reset_ctl reset;
+		int ret;
+
+		ret = reset_get_by_index(dev, i, &reset);
+		if (ret < 0)
+			break;
+
+		ret = reset_deassert(&reset);
+		if (ret < 0) {
+			pr_err("%s: error deasserting reset %d\n", __func__, i);
+			return ret;
+		}
+
+		ret = reset_free(&reset);
+		if (ret < 0) {
+			pr_err("%s: error freeing reset %d\n", __func__, i);
+			return ret;
+		}
+	}
+
+	/* set priv data */
+	priv->num_ports = num_ports;
+	if (dev_read_bool(dev, "brcm,rgmii-override"))
+		priv->rgmii_override = true;
+	if (dev_read_bool(dev, "brcm,rgmii-timing"))
+		priv->rgmii_timing = true;
+
+	/* get ports */
+	dev_for_each_subnode(node, dev) {
+		const char *comp;
+		const char *label;
+		unsigned int p;
+		int phy_id;
+		int speed;
+
+		comp = ofnode_read_string(node, "compatible");
+		if (!comp || memcmp(comp, ETH_PORT_STR, sizeof(ETH_PORT_STR)))
+			continue;
+
+		p = ofnode_read_u32_default(node, "reg", ETH_MAX_PORT);
+		if (p >= num_ports)
+			return -EINVAL;
+
+		label = ofnode_read_string(node, "label");
+		if (!label) {
+			debug("%s: node %s has no label\n", __func__,
+			      ofnode_get_name(node));
+			return -EINVAL;
+		}
+
+		phy_id = ofnode_read_u32_default(node, "brcm,phy-id", -1);
+
+		priv->used_ports[p].used = true;
+		priv->used_ports[p].name = label;
+		priv->used_ports[p].phy_id = phy_id;
+
+		if (ofnode_read_bool(node, "full-duplex"))
+			priv->used_ports[p].force_duplex_full = true;
+		if (ofnode_read_bool(node, "bypass-link"))
+			priv->used_ports[p].bypass_link = true;
+		speed = ofnode_read_u32_default(node, "speed", 0);
+		if (speed)
+			priv->used_ports[p].force_speed = speed;
+	}
+
+	/* init mii bus */
+	ret = bcm6368_mdio_init(dev->name, priv);
+	if (ret)
+		return ret;
+
+	/* disable all ports */
+	for (i = 0; i < priv->num_ports; i++) {
+		writeb_be(ETH_PORTOV_ENABLE_MASK,
+			      priv->base + ETH_PORTOV_REG(i));
+		writeb_be(ETH_PTCTRL_RXDIS_MASK |
+			      ETH_PTCTRL_TXDIS_MASK,
+			      priv->base + ETH_PTCTRL_REG(i));
+
+		priv->sw_port_link[i] = 0;
+	}
+
+	/* enable external ports */
+	for (i = ETH_RGMII_PORT0; i < priv->num_ports; i++) {
+		u8 rgmii_ctrl;
+
+		if (!priv->used_ports[i].used)
+			continue;
+
+		rgmii_ctrl = readb_be(priv->base + ETH_RGMII_CTRL_REG(i));
+		rgmii_ctrl |= ETH_RGMII_CTRL_GMII_CLK_EN;
+		if (priv->rgmii_override)
+			rgmii_ctrl |= ETH_RGMII_CTRL_MII_OVERRIDE_EN;
+		if (priv->rgmii_timing)
+			rgmii_ctrl |= ETH_RGMII_CTRL_TIMING_SEL_EN;
+		writeb_be(rgmii_ctrl, priv->base + ETH_RGMII_CTRL_REG(i));
+	}
+
+	/* reset mib */
+	val = readb_be(priv->base + ETH_GMCR_REG);
+	val |= ETH_GMCR_RST_MIB_MASK;
+	writeb_be(val, priv->base + ETH_GMCR_REG);
+	mdelay(1);
+	val &= ~ETH_GMCR_RST_MIB_MASK;
+	writeb_be(val, priv->base + ETH_GMCR_REG);
+	mdelay(1);
+
+	/* force CPU port state */
+	val = readb_be(priv->base + ETH_IMPOV_REG);
+	val |= ETH_IMPOV_FORCE_MASK | ETH_IMPOV_LINKUP_MASK;
+	writeb_be(val, priv->base + ETH_IMPOV_REG);
+
+	/* enable switch forward engine */
+	val = readb_be(priv->base + ETH_SWMODE_REG);
+	val |= ETH_SWMODE_FWD_EN_MASK;
+	writeb_be(val, priv->base + ETH_SWMODE_REG);
+
+	/* enable jumbo on all ports */
+	writel_be(0x1ff, priv->base + ETH_JMBCTL_PORT_REG);
+	writew_be(9728, priv->base + ETH_JMBCTL_MAXSIZE_REG);
+
+	return 0;
+}
+
+U_BOOT_DRIVER(bcm6368_eth) = {
+	.name = "bcm6368_eth",
+	.id = UCLASS_ETH,
+	.of_match = bcm6368_eth_ids,
+	.ops = &bcm6368_eth_ops,
+	.platdata_auto_alloc_size = sizeof(struct eth_pdata),
+	.priv_auto_alloc_size = sizeof(struct bcm6368_eth_priv),
+	.probe = bcm6368_eth_probe,
+};