designware.c

/*
 * (C) Copyright 2010
 * Vipin Kumar, ST Micoelectronics, vipin.kumar@st.com.
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

/*
 * Designware ethernet IP driver for u-boot
 */

#include <common.h>
#include <miiphy.h>
#include <malloc.h>
#include <linux/compiler.h>
#include <linux/err.h>
#include <asm/io.h>
#include "designware.h"

#if !defined(CONFIG_PHYLIB)
# error "DesignWare Ether MAC requires PHYLIB - missing CONFIG_PHYLIB"
#endif

static int dw_mdio_read(struct mii_dev *bus, int addr, int devad, int reg)
{
	struct eth_mac_regs *mac_p = bus->priv;
	ulong start;
	u16 miiaddr;
	int timeout = CONFIG_MDIO_TIMEOUT;

	miiaddr = ((addr << MIIADDRSHIFT) & MII_ADDRMSK) |
		  ((reg << MIIREGSHIFT) & MII_REGMSK);

	writel(miiaddr | MII_CLKRANGE_150_250M | MII_BUSY, &mac_p->miiaddr);

	start = get_timer(0);
	while (get_timer(start) < timeout) {
		if (!(readl(&mac_p->miiaddr) & MII_BUSY))
			return readl(&mac_p->miidata);
		udelay(10);
	};

	return -1;
}

static int dw_mdio_write(struct mii_dev *bus, int addr, int devad, int reg,
			u16 val)
{
	struct eth_mac_regs *mac_p = bus->priv;
	ulong start;
	u16 miiaddr;
	int ret = -1, timeout = CONFIG_MDIO_TIMEOUT;

	writel(val, &mac_p->miidata);
	miiaddr = ((addr << MIIADDRSHIFT) & MII_ADDRMSK) |
		  ((reg << MIIREGSHIFT) & MII_REGMSK) | MII_WRITE;

	writel(miiaddr | MII_CLKRANGE_150_250M | MII_BUSY, &mac_p->miiaddr);

	start = get_timer(0);
	while (get_timer(start) < timeout) {
		if (!(readl(&mac_p->miiaddr) & MII_BUSY)) {
			ret = 0;
			break;
		}
		udelay(10);
	};

	return ret;
}

static int dw_mdio_init(char *name, struct eth_mac_regs *mac_regs_p)
{
	struct mii_dev *bus = mdio_alloc();

	if (!bus) {
		printf("Failed to allocate MDIO bus\n");
		return -1;
	}

	bus->read = dw_mdio_read;
	bus->write = dw_mdio_write;
	sprintf(bus->name, name);

	bus->priv = (void *)mac_regs_p;

	return mdio_register(bus);
}

static void tx_descs_init(struct eth_device *dev)
{
	struct dw_eth_dev *priv = dev->priv;
	struct eth_dma_regs *dma_p = priv->dma_regs_p;
	struct dmamacdescr *desc_table_p = &priv->tx_mac_descrtable[0];
	char *txbuffs = &priv->txbuffs[0];
	struct dmamacdescr *desc_p;
	u32 idx;

	for (idx = 0; idx < CONFIG_TX_DESCR_NUM; idx++) {
		desc_p = &desc_table_p[idx];
		desc_p->dmamac_addr = &txbuffs[idx * CONFIG_ETH_BUFSIZE];
		desc_p->dmamac_next = &desc_table_p[idx + 1];

#if defined(CONFIG_DW_ALTDESCRIPTOR)
		desc_p->txrx_status &= ~(DESC_TXSTS_TXINT | DESC_TXSTS_TXLAST |
				DESC_TXSTS_TXFIRST | DESC_TXSTS_TXCRCDIS | \
				DESC_TXSTS_TXCHECKINSCTRL | \
				DESC_TXSTS_TXRINGEND | DESC_TXSTS_TXPADDIS);

		desc_p->txrx_status |= DESC_TXSTS_TXCHAIN;
		desc_p->dmamac_cntl = 0;
		desc_p->txrx_status &= ~(DESC_TXSTS_MSK | DESC_TXSTS_OWNBYDMA);
#else
		desc_p->dmamac_cntl = DESC_TXCTRL_TXCHAIN;
		desc_p->txrx_status = 0;
#endif
	}

	/* Correcting the last pointer of the chain */
	desc_p->dmamac_next = &desc_table_p[0];

	/* Flush all Tx buffer descriptors at once */
	flush_dcache_range((unsigned int)priv->tx_mac_descrtable,
			   (unsigned int)priv->tx_mac_descrtable +
			   sizeof(priv->tx_mac_descrtable));

	writel((ulong)&desc_table_p[0], &dma_p->txdesclistaddr);
	priv->tx_currdescnum = 0;
}

static void rx_descs_init(struct eth_device *dev)
{
	struct dw_eth_dev *priv = dev->priv;
	struct eth_dma_regs *dma_p = priv->dma_regs_p;
	struct dmamacdescr *desc_table_p = &priv->rx_mac_descrtable[0];
	char *rxbuffs = &priv->rxbuffs[0];
	struct dmamacdescr *desc_p;
	u32 idx;

	/* Before passing buffers to GMAC we need to make sure zeros
	 * written there right after "priv" structure allocation were
	 * flushed into RAM.
	 * Otherwise there's a chance to get some of them flushed in RAM when
	 * GMAC is already pushing data to RAM via DMA. This way incoming from
	 * GMAC data will be corrupted. */
	flush_dcache_range((unsigned int)rxbuffs, (unsigned int)rxbuffs +
			   RX_TOTAL_BUFSIZE);

	for (idx = 0; idx < CONFIG_RX_DESCR_NUM; idx++) {
		desc_p = &desc_table_p[idx];
		desc_p->dmamac_addr = &rxbuffs[idx * CONFIG_ETH_BUFSIZE];
		desc_p->dmamac_next = &desc_table_p[idx + 1];

		desc_p->dmamac_cntl =
			(MAC_MAX_FRAME_SZ & DESC_RXCTRL_SIZE1MASK) | \
				      DESC_RXCTRL_RXCHAIN;

		desc_p->txrx_status = DESC_RXSTS_OWNBYDMA;
	}

	/* Correcting the last pointer of the chain */
	desc_p->dmamac_next = &desc_table_p[0];

	/* Flush all Rx buffer descriptors at once */
	flush_dcache_range((unsigned int)priv->rx_mac_descrtable,
			   (unsigned int)priv->rx_mac_descrtable +
			   sizeof(priv->rx_mac_descrtable));

	writel((ulong)&desc_table_p[0], &dma_p->rxdesclistaddr);
	priv->rx_currdescnum = 0;
}

static int dw_write_hwaddr(struct eth_device *dev)
{
	struct dw_eth_dev *priv = dev->priv;
	struct eth_mac_regs *mac_p = priv->mac_regs_p;
	u32 macid_lo, macid_hi;
	u8 *mac_id = &dev->enetaddr[0];

	macid_lo = mac_id[0] + (mac_id[1] << 8) + (mac_id[2] << 16) +
		   (mac_id[3] << 24);
	macid_hi = mac_id[4] + (mac_id[5] << 8);

	writel(macid_hi, &mac_p->macaddr0hi);
	writel(macid_lo, &mac_p->macaddr0lo);

	return 0;
}

static void dw_adjust_link(struct eth_mac_regs *mac_p,
			   struct phy_device *phydev)
{
	u32 conf = readl(&mac_p->conf) | FRAMEBURSTENABLE | DISABLERXOWN;

	if (!phydev->link) {
		printf("%s: No link.\n", phydev->dev->name);
		return;
	}

	if (phydev->speed != 1000)
		conf |= MII_PORTSELECT;

	if (phydev->speed == 100)
		conf |= FES_100;

	if (phydev->duplex)
		conf |= FULLDPLXMODE;

	writel(conf, &mac_p->conf);

	printf("Speed: %d, %s duplex%s\n", phydev->speed,
	       (phydev->duplex) ? "full" : "half",
	       (phydev->port == PORT_FIBRE) ? ", fiber mode" : "");
}

static void dw_eth_halt(struct eth_device *dev)
{
	struct dw_eth_dev *priv = dev->priv;
	struct eth_mac_regs *mac_p = priv->mac_regs_p;
	struct eth_dma_regs *dma_p = priv->dma_regs_p;

	writel(readl(&mac_p->conf) & ~(RXENABLE | TXENABLE), &mac_p->conf);
	writel(readl(&dma_p->opmode) & ~(RXSTART | TXSTART), &dma_p->opmode);

	phy_shutdown(priv->phydev);
}

static int dw_eth_init(struct eth_device *dev, bd_t *bis)
{
	struct dw_eth_dev *priv = dev->priv;
	struct eth_mac_regs *mac_p = priv->mac_regs_p;
	struct eth_dma_regs *dma_p = priv->dma_regs_p;
	unsigned int start;

	writel(readl(&dma_p->busmode) | DMAMAC_SRST, &dma_p->busmode);

	start = get_timer(0);
	while (readl(&dma_p->busmode) & DMAMAC_SRST) {
		if (get_timer(start) >= CONFIG_MACRESET_TIMEOUT) {
			printf("DMA reset timeout\n");
			return -1;
		}

		mdelay(100);
	};

	/* Soft reset above clears HW address registers.
	 * So we have to set it here once again */
	dw_write_hwaddr(dev);

	rx_descs_init(dev);
	tx_descs_init(dev);

	writel(FIXEDBURST | PRIORXTX_41 | DMA_PBL, &dma_p->busmode);

#ifndef CONFIG_DW_MAC_FORCE_THRESHOLD_MODE
	writel(readl(&dma_p->opmode) | FLUSHTXFIFO | STOREFORWARD,
	       &dma_p->opmode);
#else
	writel(readl(&dma_p->opmode) | FLUSHTXFIFO,
	       &dma_p->opmode);
#endif

	writel(readl(&dma_p->opmode) | RXSTART | TXSTART, &dma_p->opmode);

#ifdef CONFIG_DW_AXI_BURST_LEN
	writel((CONFIG_DW_AXI_BURST_LEN & 0x1FF >> 1), &dma_p->axibus);
#endif

	/* Start up the PHY */
	if (phy_startup(priv->phydev)) {
		printf("Could not initialize PHY %s\n",
		       priv->phydev->dev->name);
		return -1;
	}

	dw_adjust_link(mac_p, priv->phydev);

	if (!priv->phydev->link)
		return -1;

	writel(readl(&mac_p->conf) | RXENABLE | TXENABLE, &mac_p->conf);

	return 0;
}

static int dw_eth_send(struct eth_device *dev, void *packet, int length)
{
	struct dw_eth_dev *priv = dev->priv;
	struct eth_dma_regs *dma_p = priv->dma_regs_p;
	u32 desc_num = priv->tx_currdescnum;
	struct dmamacdescr *desc_p = &priv->tx_mac_descrtable[desc_num];
	uint32_t desc_start = (uint32_t)desc_p;
	uint32_t desc_end = desc_start +
		roundup(sizeof(*desc_p), ARCH_DMA_MINALIGN);
	uint32_t data_start = (uint32_t)desc_p->dmamac_addr;
	uint32_t data_end = data_start +
		roundup(length, ARCH_DMA_MINALIGN);
	/*
	 * Strictly we only need to invalidate the "txrx_status" field
	 * for the following check, but on some platforms we cannot
	 * invalidate only 4 bytes, so we flush the entire descriptor,
	 * which is 16 bytes in total. This is safe because the
	 * individual descriptors in the array are each aligned to
	 * ARCH_DMA_MINALIGN and padded appropriately.
	 */
	invalidate_dcache_range(desc_start, desc_end);

	/* Check if the descriptor is owned by CPU */
	if (desc_p->txrx_status & DESC_TXSTS_OWNBYDMA) {
		printf("CPU not owner of tx frame\n");
		return -1;
	}

	memcpy(desc_p->dmamac_addr, packet, length);

	/* Flush data to be sent */
	flush_dcache_range(data_start, data_end);

#if defined(CONFIG_DW_ALTDESCRIPTOR)
	desc_p->txrx_status |= DESC_TXSTS_TXFIRST | DESC_TXSTS_TXLAST;
	desc_p->dmamac_cntl |= (length << DESC_TXCTRL_SIZE1SHFT) & \
			       DESC_TXCTRL_SIZE1MASK;

	desc_p->txrx_status &= ~(DESC_TXSTS_MSK);
	desc_p->txrx_status |= DESC_TXSTS_OWNBYDMA;
#else
	desc_p->dmamac_cntl |= ((length << DESC_TXCTRL_SIZE1SHFT) & \
			       DESC_TXCTRL_SIZE1MASK) | DESC_TXCTRL_TXLAST | \
			       DESC_TXCTRL_TXFIRST;

	desc_p->txrx_status = DESC_TXSTS_OWNBYDMA;
#endif

	/* Flush modified buffer descriptor */
	flush_dcache_range(desc_start, desc_end);

	/* Test the wrap-around condition. */
	if (++desc_num >= CONFIG_TX_DESCR_NUM)
		desc_num = 0;

	priv->tx_currdescnum = desc_num;

	/* Start the transmission */
	writel(POLL_DATA, &dma_p->txpolldemand);

	return 0;
}

static int dw_eth_recv(struct eth_device *dev)
{
	struct dw_eth_dev *priv = dev->priv;
	u32 status, desc_num = priv->rx_currdescnum;
	struct dmamacdescr *desc_p = &priv->rx_mac_descrtable[desc_num];
	int length = 0;
	uint32_t desc_start = (uint32_t)desc_p;
	uint32_t desc_end = desc_start +
		roundup(sizeof(*desc_p), ARCH_DMA_MINALIGN);
	uint32_t data_start = (uint32_t)desc_p->dmamac_addr;
	uint32_t data_end;

	/* Invalidate entire buffer descriptor */
	invalidate_dcache_range(desc_start, desc_end);

	status = desc_p->txrx_status;

	/* Check  if the owner is the CPU */
	if (!(status & DESC_RXSTS_OWNBYDMA)) {

		length = (status & DESC_RXSTS_FRMLENMSK) >> \
			 DESC_RXSTS_FRMLENSHFT;

		/* Invalidate received data */
		data_end = data_start + roundup(length, ARCH_DMA_MINALIGN);
		invalidate_dcache_range(data_start, data_end);

		net_process_received_packet(desc_p->dmamac_addr, length);

		/*
		 * Make the current descriptor valid again and go to
		 * the next one
		 */
		desc_p->txrx_status |= DESC_RXSTS_OWNBYDMA;

		/* Flush only status field - others weren't changed */
		flush_dcache_range(desc_start, desc_end);

		/* Test the wrap-around condition. */
		if (++desc_num >= CONFIG_RX_DESCR_NUM)
			desc_num = 0;
	}

	priv->rx_currdescnum = desc_num;

	return length;
}

static int dw_phy_init(struct eth_device *dev)
{
	struct dw_eth_dev *priv = dev->priv;
	struct phy_device *phydev;
	int mask = 0xffffffff;

#ifdef CONFIG_PHY_ADDR
	mask = 1 << CONFIG_PHY_ADDR;
#endif

	phydev = phy_find_by_mask(priv->bus, mask, priv->interface);
	if (!phydev)
		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 designware_initialize(ulong base_addr, u32 interface)
{
	struct eth_device *dev;
	struct dw_eth_dev *priv;

	dev = (struct eth_device *) malloc(sizeof(struct eth_device));
	if (!dev)
		return -ENOMEM;

	/*
	 * Since the priv structure contains the descriptors which need a strict
	 * buswidth alignment, memalign is used to allocate memory
	 */
	priv = (struct dw_eth_dev *) memalign(ARCH_DMA_MINALIGN,
					      sizeof(struct dw_eth_dev));
	if (!priv) {
		free(dev);
		return -ENOMEM;
	}

	memset(dev, 0, sizeof(struct eth_device));
	memset(priv, 0, sizeof(struct dw_eth_dev));

	sprintf(dev->name, "dwmac.%lx", base_addr);
	dev->iobase = (int)base_addr;
	dev->priv = priv;

	priv->dev = dev;
	priv->mac_regs_p = (struct eth_mac_regs *)base_addr;
	priv->dma_regs_p = (struct eth_dma_regs *)(base_addr +
			DW_DMA_BASE_OFFSET);

	dev->init = dw_eth_init;
	dev->send = dw_eth_send;
	dev->recv = dw_eth_recv;
	dev->halt = dw_eth_halt;
	dev->write_hwaddr = dw_write_hwaddr;

	eth_register(dev);

	priv->interface = interface;

	dw_mdio_init(dev->name, priv->mac_regs_p);
	priv->bus = miiphy_get_dev_by_name(dev->name);

	return dw_phy_init(dev);
}