net: Add Intel Topcliff GMAC driver

Add a new driver for the Gigabit Ethernet MAC found on Intel Topcliff
Platform Controller Hub. Tested under 10/100 half/full duplex and 1000
full duplex modes using ping and tftpboot commands.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
diff --git a/drivers/net/pch_gbe.c b/drivers/net/pch_gbe.c
new file mode 100644
index 0000000..976848d
--- /dev/null
+++ b/drivers/net/pch_gbe.c
@@ -0,0 +1,466 @@
+/*
+ * Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
+ *
+ * Intel Platform Controller Hub EG20T (codename Topcliff) GMAC Driver
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <errno.h>
+#include <asm/io.h>
+#include <pci.h>
+#include <malloc.h>
+#include <miiphy.h>
+#include "pch_gbe.h"
+
+#if !defined(CONFIG_PHYLIB)
+# error "PCH Gigabit Ethernet driver requires PHYLIB - missing CONFIG_PHYLIB"
+#endif
+
+static struct pci_device_id supported[] = {
+	{ PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_TCF_GBE },
+	{ }
+};
+
+static void pch_gbe_mac_read(struct pch_gbe_regs *mac_regs, u8 *addr)
+{
+	u32 macid_hi, macid_lo;
+
+	macid_hi = readl(&mac_regs->mac_adr[0].high);
+	macid_lo = readl(&mac_regs->mac_adr[0].low) & 0xffff;
+	debug("pch_gbe: macid_hi %#x macid_lo %#x\n", macid_hi, macid_lo);
+
+	addr[0] = (u8)(macid_hi & 0xff);
+	addr[1] = (u8)((macid_hi >> 8) & 0xff);
+	addr[2] = (u8)((macid_hi >> 16) & 0xff);
+	addr[3] = (u8)((macid_hi >> 24) & 0xff);
+	addr[4] = (u8)(macid_lo & 0xff);
+	addr[5] = (u8)((macid_lo >> 8) & 0xff);
+}
+
+static int pch_gbe_mac_write(struct pch_gbe_regs *mac_regs, u8 *addr)
+{
+	u32 macid_hi, macid_lo;
+	ulong start;
+
+	macid_hi = addr[0] + (addr[1] << 8) + (addr[2] << 16) + (addr[3] << 24);
+	macid_lo = addr[4] + (addr[5] << 8);
+
+	writel(macid_hi, &mac_regs->mac_adr[0].high);
+	writel(macid_lo, &mac_regs->mac_adr[0].low);
+	writel(0xfffe, &mac_regs->addr_mask);
+
+	start = get_timer(0);
+	while (get_timer(start) < PCH_GBE_TIMEOUT) {
+		if (!(readl(&mac_regs->addr_mask) & PCH_GBE_BUSY))
+			return 0;
+
+		udelay(10);
+	}
+
+	return -ETIME;
+}
+
+static int pch_gbe_reset(struct eth_device *dev)
+{
+	struct pch_gbe_priv *priv = dev->priv;
+	struct pch_gbe_regs *mac_regs = priv->mac_regs;
+	ulong start;
+
+	priv->rx_idx = 0;
+	priv->tx_idx = 0;
+
+	writel(PCH_GBE_ALL_RST, &mac_regs->reset);
+
+	/*
+	 * Configure the MAC to RGMII mode after reset
+	 *
+	 * For some unknown reason, we must do the configuration here right
+	 * after resetting the whole MAC, otherwise the reset bit in the RESET
+	 * register will never be cleared by the hardware. And there is another
+	 * way of having the same magic, that is to configure the MODE register
+	 * to have the MAC work in MII/GMII mode, which is how current Linux
+	 * pch_gbe driver does. Since anyway we need program the MAC to RGMII
+	 * mode in the driver, we just do it here.
+	 *
+	 * Note: this behavior is not documented in the hardware manual.
+	 */
+	writel(PCH_GBE_RGMII_MODE_RGMII | PCH_GBE_CHIP_TYPE_INTERNAL,
+	       &mac_regs->rgmii_ctrl);
+
+	start = get_timer(0);
+	while (get_timer(start) < PCH_GBE_TIMEOUT) {
+		if (!(readl(&mac_regs->reset) & PCH_GBE_ALL_RST)) {
+			/*
+			 * Soft reset clears hardware MAC address registers,
+			 * so we have to reload MAC address here in order to
+			 * make linux pch_gbe driver happy.
+			 */
+			return pch_gbe_mac_write(mac_regs, dev->enetaddr);
+		}
+
+		udelay(10);
+	}
+
+	debug("pch_gbe: reset timeout\n");
+	return -ETIME;
+}
+
+static void pch_gbe_rx_descs_init(struct eth_device *dev)
+{
+	struct pch_gbe_priv *priv = dev->priv;
+	struct pch_gbe_regs *mac_regs = priv->mac_regs;
+	struct pch_gbe_rx_desc *rx_desc = &priv->rx_desc[0];
+	int i;
+
+	memset(rx_desc, 0, sizeof(struct pch_gbe_rx_desc) * PCH_GBE_DESC_NUM);
+	for (i = 0; i < PCH_GBE_DESC_NUM; i++)
+		rx_desc->buffer_addr = pci_phys_to_mem(priv->bdf,
+			(u32)(priv->rx_buff[i]));
+
+	writel(pci_phys_to_mem(priv->bdf, (u32)rx_desc),
+	       &mac_regs->rx_dsc_base);
+	writel(sizeof(struct pch_gbe_rx_desc) * (PCH_GBE_DESC_NUM - 1),
+	       &mac_regs->rx_dsc_size);
+
+	writel(pci_phys_to_mem(priv->bdf, (u32)(rx_desc + 1)),
+	       &mac_regs->rx_dsc_sw_p);
+}
+
+static void pch_gbe_tx_descs_init(struct eth_device *dev)
+{
+	struct pch_gbe_priv *priv = dev->priv;
+	struct pch_gbe_regs *mac_regs = priv->mac_regs;
+	struct pch_gbe_tx_desc *tx_desc = &priv->tx_desc[0];
+
+	memset(tx_desc, 0, sizeof(struct pch_gbe_tx_desc) * PCH_GBE_DESC_NUM);
+
+	writel(pci_phys_to_mem(priv->bdf, (u32)tx_desc),
+	       &mac_regs->tx_dsc_base);
+	writel(sizeof(struct pch_gbe_tx_desc) * (PCH_GBE_DESC_NUM - 1),
+	       &mac_regs->tx_dsc_size);
+	writel(pci_phys_to_mem(priv->bdf, (u32)(tx_desc + 1)),
+	       &mac_regs->tx_dsc_sw_p);
+}
+
+static void pch_gbe_adjust_link(struct pch_gbe_regs *mac_regs,
+				struct phy_device *phydev)
+{
+	if (!phydev->link) {
+		printf("%s: No link.\n", phydev->dev->name);
+		return;
+	}
+
+	clrbits_le32(&mac_regs->rgmii_ctrl,
+		     PCH_GBE_RGMII_RATE_2_5M | PCH_GBE_CRS_SEL);
+	clrbits_le32(&mac_regs->mode,
+		     PCH_GBE_MODE_GMII_ETHER | PCH_GBE_MODE_FULL_DUPLEX);
+
+	switch (phydev->speed) {
+	case 1000:
+		setbits_le32(&mac_regs->rgmii_ctrl, PCH_GBE_RGMII_RATE_125M);
+		setbits_le32(&mac_regs->mode, PCH_GBE_MODE_GMII_ETHER);
+		break;
+	case 100:
+		setbits_le32(&mac_regs->rgmii_ctrl, PCH_GBE_RGMII_RATE_25M);
+		setbits_le32(&mac_regs->mode, PCH_GBE_MODE_MII_ETHER);
+		break;
+	case 10:
+		setbits_le32(&mac_regs->rgmii_ctrl, PCH_GBE_RGMII_RATE_2_5M);
+		setbits_le32(&mac_regs->mode, PCH_GBE_MODE_MII_ETHER);
+		break;
+	}
+
+	if (phydev->duplex) {
+		setbits_le32(&mac_regs->rgmii_ctrl, PCH_GBE_CRS_SEL);
+		setbits_le32(&mac_regs->mode, PCH_GBE_MODE_FULL_DUPLEX);
+	}
+
+	printf("Speed: %d, %s duplex\n", phydev->speed,
+	       (phydev->duplex) ? "full" : "half");
+
+	return;
+}
+
+static int pch_gbe_init(struct eth_device *dev, bd_t *bis)
+{
+	struct pch_gbe_priv *priv = dev->priv;
+	struct pch_gbe_regs *mac_regs = priv->mac_regs;
+
+	if (pch_gbe_reset(dev))
+		return -1;
+
+	pch_gbe_rx_descs_init(dev);
+	pch_gbe_tx_descs_init(dev);
+
+	/* Enable frame bursting */
+	writel(PCH_GBE_MODE_FR_BST, &mac_regs->mode);
+	/* Disable TCP/IP accelerator */
+	writel(PCH_GBE_RX_TCPIPACC_OFF, &mac_regs->tcpip_acc);
+	/* Disable RX flow control */
+	writel(0, &mac_regs->rx_fctrl);
+	/* Configure RX/TX mode */
+	writel(PCH_GBE_RH_ALM_EMP_16 | PCH_GBE_RH_ALM_FULL_16 |
+	       PCH_GBE_RH_RD_TRG_32, &mac_regs->rx_mode);
+	writel(PCH_GBE_TM_TH_TX_STRT_32 | PCH_GBE_TM_TH_ALM_EMP_16 |
+	       PCH_GBE_TM_TH_ALM_FULL_32 | PCH_GBE_TM_ST_AND_FD |
+	       PCH_GBE_TM_SHORT_PKT, &mac_regs->tx_mode);
+
+	/* Start up the PHY */
+	if (phy_startup(priv->phydev)) {
+		printf("Could not initialize PHY %s\n",
+		       priv->phydev->dev->name);
+		return -1;
+	}
+
+	pch_gbe_adjust_link(mac_regs, priv->phydev);
+
+	if (!priv->phydev->link)
+		return -1;
+
+	/* Enable TX & RX */
+	writel(PCH_GBE_RX_DMA_EN | PCH_GBE_TX_DMA_EN, &mac_regs->dma_ctrl);
+	writel(PCH_GBE_MRE_MAC_RX_EN, &mac_regs->mac_rx_en);
+
+	return 0;
+}
+
+static void pch_gbe_halt(struct eth_device *dev)
+{
+	struct pch_gbe_priv *priv = dev->priv;
+
+	pch_gbe_reset(dev);
+
+	phy_shutdown(priv->phydev);
+}
+
+static int pch_gbe_send(struct eth_device *dev, void *packet, int length)
+{
+	struct pch_gbe_priv *priv = dev->priv;
+	struct pch_gbe_regs *mac_regs = priv->mac_regs;
+	struct pch_gbe_tx_desc *tx_head, *tx_desc;
+	u16 frame_ctrl = 0;
+	u32 int_st;
+	ulong start;
+
+	tx_head = &priv->tx_desc[0];
+	tx_desc = &priv->tx_desc[priv->tx_idx];
+
+	if (length < 64)
+		frame_ctrl |= PCH_GBE_TXD_CTRL_APAD;
+
+	tx_desc->buffer_addr = pci_phys_to_mem(priv->bdf, (u32)packet);
+	tx_desc->length = length;
+	tx_desc->tx_words_eob = length + 3;
+	tx_desc->tx_frame_ctrl = frame_ctrl;
+	tx_desc->dma_status = 0;
+	tx_desc->gbec_status = 0;
+
+	/* Test the wrap-around condition */
+	if (++priv->tx_idx >= PCH_GBE_DESC_NUM)
+		priv->tx_idx = 0;
+
+	writel(pci_phys_to_mem(priv->bdf, (u32)(tx_head + priv->tx_idx)),
+	       &mac_regs->tx_dsc_sw_p);
+
+	start = get_timer(0);
+	while (get_timer(start) < PCH_GBE_TIMEOUT) {
+		int_st = readl(&mac_regs->int_st);
+		if (int_st & PCH_GBE_INT_TX_CMPLT)
+			return 0;
+
+		udelay(10);
+	}
+
+	debug("pch_gbe: sent failed\n");
+	return -ETIME;
+}
+
+static int pch_gbe_recv(struct eth_device *dev)
+{
+	struct pch_gbe_priv *priv = dev->priv;
+	struct pch_gbe_regs *mac_regs = priv->mac_regs;
+	struct pch_gbe_rx_desc *rx_head, *rx_desc;
+	u32 hw_desc, buffer_addr, length;
+	int rx_swp;
+
+	rx_head = &priv->rx_desc[0];
+	rx_desc = &priv->rx_desc[priv->rx_idx];
+
+	readl(&mac_regs->int_st);
+	hw_desc = readl(&mac_regs->rx_dsc_hw_p_hld);
+
+	/* Just return if not receiving any packet */
+	if ((u32)rx_desc == hw_desc)
+		return 0;
+
+	buffer_addr = pci_mem_to_phys(priv->bdf, rx_desc->buffer_addr);
+	length = rx_desc->rx_words_eob - 3 - ETH_FCS_LEN;
+	NetReceive((uchar *)buffer_addr, length);
+
+	/* Test the wrap-around condition */
+	if (++priv->rx_idx >= PCH_GBE_DESC_NUM)
+		priv->rx_idx = 0;
+	rx_swp = priv->rx_idx;
+	if (++rx_swp >= PCH_GBE_DESC_NUM)
+		rx_swp = 0;
+
+	writel(pci_phys_to_mem(priv->bdf, (u32)(rx_head + rx_swp)),
+	       &mac_regs->rx_dsc_sw_p);
+
+	return length;
+}
+
+static int pch_gbe_mdio_ready(struct pch_gbe_regs *mac_regs)
+{
+	ulong start = get_timer(0);
+
+	while (get_timer(start) < PCH_GBE_TIMEOUT) {
+		if (readl(&mac_regs->miim) & PCH_GBE_MIIM_OPER_READY)
+			return 0;
+
+		udelay(10);
+	}
+
+	return -ETIME;
+}
+
+static int pch_gbe_mdio_read(struct mii_dev *bus, int addr, int devad, int reg)
+{
+	struct pch_gbe_regs *mac_regs = bus->priv;
+	u32 miim;
+
+	if (pch_gbe_mdio_ready(mac_regs))
+		return -ETIME;
+
+	miim = (addr << PCH_GBE_MIIM_PHY_ADDR_SHIFT) |
+	       (reg << PCH_GBE_MIIM_REG_ADDR_SHIFT) |
+	       PCH_GBE_MIIM_OPER_READ;
+	writel(miim, &mac_regs->miim);
+
+	if (pch_gbe_mdio_ready(mac_regs))
+		return -ETIME;
+
+	return readl(&mac_regs->miim) & 0xffff;
+}
+
+static int pch_gbe_mdio_write(struct mii_dev *bus, int addr, int devad,
+			      int reg, u16 val)
+{
+	struct pch_gbe_regs *mac_regs = bus->priv;
+	u32 miim;
+
+	if (pch_gbe_mdio_ready(mac_regs))
+		return -ETIME;
+
+	miim = (addr << PCH_GBE_MIIM_PHY_ADDR_SHIFT) |
+	       (reg << PCH_GBE_MIIM_REG_ADDR_SHIFT) |
+	       PCH_GBE_MIIM_OPER_WRITE | val;
+	writel(miim, &mac_regs->miim);
+
+	if (pch_gbe_mdio_ready(mac_regs))
+		return -ETIME;
+	else
+		return 0;
+}
+
+static int pch_gbe_mdio_init(char *name, struct pch_gbe_regs *mac_regs)
+{
+	struct mii_dev *bus;
+
+	bus = mdio_alloc();
+	if (!bus) {
+		debug("pch_gbe: failed to allocate MDIO bus\n");
+		return -ENOMEM;
+	}
+
+	bus->read = pch_gbe_mdio_read;
+	bus->write = pch_gbe_mdio_write;
+	sprintf(bus->name, name);
+
+	bus->priv = (void *)mac_regs;
+
+	return mdio_register(bus);
+}
+
+static int pch_gbe_phy_init(struct eth_device *dev)
+{
+	struct pch_gbe_priv *priv = dev->priv;
+	struct phy_device *phydev;
+	int mask = 0xffffffff;
+
+	phydev = phy_find_by_mask(priv->bus, mask, priv->interface);
+	if (!phydev) {
+		printf("pch_gbe: cannot find the phy\n");
+		return -1;
+	}
+
+	phy_connect_dev(phydev, dev);
+
+	phydev->supported &= PHY_GBIT_FEATURES;
+	phydev->advertising = phydev->supported;
+
+	priv->phydev = phydev;
+	phy_config(phydev);
+
+	return 1;
+}
+
+int pch_gbe_register(bd_t *bis)
+{
+	struct eth_device *dev;
+	struct pch_gbe_priv *priv;
+	pci_dev_t devno;
+	u32 iobase;
+
+	devno = pci_find_devices(supported, 0);
+	if (devno == -1)
+		return -ENODEV;
+
+	dev = (struct eth_device *)malloc(sizeof(*dev));
+	if (!dev)
+		return -ENOMEM;
+	memset(dev, 0, sizeof(*dev));
+
+	/*
+	 * The priv structure contains the descriptors and frame buffers which
+	 * need a strict buswidth alignment (64 bytes)
+	 */
+	priv = (struct pch_gbe_priv *)memalign(PCH_GBE_ALIGN_SIZE,
+					       sizeof(*priv));
+	if (!priv) {
+		free(dev);
+		return -ENOMEM;
+	}
+	memset(priv, 0, sizeof(*priv));
+
+	dev->priv = priv;
+	priv->dev = dev;
+	priv->bdf = devno;
+
+	pci_read_config_dword(devno, PCI_BASE_ADDRESS_1, &iobase);
+	iobase &= PCI_BASE_ADDRESS_MEM_MASK;
+	iobase = pci_mem_to_phys(devno, iobase);
+
+	dev->iobase = iobase;
+	priv->mac_regs = (struct pch_gbe_regs *)iobase;
+
+	sprintf(dev->name, "pch_gbe.%x", iobase);
+
+	/* Read MAC address from SROM and initialize dev->enetaddr with it */
+	pch_gbe_mac_read(priv->mac_regs, dev->enetaddr);
+
+	dev->init = pch_gbe_init;
+	dev->halt = pch_gbe_halt;
+	dev->send = pch_gbe_send;
+	dev->recv = pch_gbe_recv;
+
+	eth_register(dev);
+
+	priv->interface = PHY_INTERFACE_MODE_RGMII;
+	pch_gbe_mdio_init(dev->name, priv->mac_regs);
+	priv->bus = miiphy_get_dev_by_name(dev->name);
+
+	return pch_gbe_phy_init(dev);
+}