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  • /*
     * CPSW Ethernet Switch Driver
     *
     * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com/
     *
     * This program is free software; you can redistribute it and/or
     * modify it under the terms of the GNU General Public License as
     * published by the Free Software Foundation version 2.
     *
     * This program is distributed "as is" WITHOUT ANY WARRANTY of any
     * kind, whether express or implied; without even the implied warranty
     * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
     * GNU General Public License for more details.
     */
    
    #include <common.h>
    #include <command.h>
    #include <net.h>
    #include <miiphy.h>
    #include <malloc.h>
    #include <net.h>
    #include <netdev.h>
    #include <cpsw.h>
    #include <asm/errno.h>
    #include <asm/io.h>
    #include <phy.h>
    
    #include <asm/arch/cpu.h>
    
    
    #define BITMASK(bits)		(BIT(bits) - 1)
    #define PHY_REG_MASK		0x1f
    #define PHY_ID_MASK		0x1f
    #define NUM_DESCS		(PKTBUFSRX * 2)
    #define PKT_MIN			60
    #define PKT_MAX			(1500 + 14 + 4 + 4)
    #define CLEAR_BIT		1
    #define GIGABITEN		BIT(7)
    #define FULLDUPLEXEN		BIT(0)
    #define MIIEN			BIT(15)
    
    /* DMA Registers */
    #define CPDMA_TXCONTROL		0x004
    #define CPDMA_RXCONTROL		0x014
    #define CPDMA_SOFTRESET		0x01c
    #define CPDMA_RXFREE		0x0e0
    #define CPDMA_TXHDP_VER1	0x100
    #define CPDMA_TXHDP_VER2	0x200
    #define CPDMA_RXHDP_VER1	0x120
    #define CPDMA_RXHDP_VER2	0x220
    #define CPDMA_TXCP_VER1		0x140
    #define CPDMA_TXCP_VER2		0x240
    #define CPDMA_RXCP_VER1		0x160
    #define CPDMA_RXCP_VER2		0x260
    
    #define CPDMA_RAM_ADDR		0x4a102000
    
    /* Descriptor mode bits */
    #define CPDMA_DESC_SOP		BIT(31)
    #define CPDMA_DESC_EOP		BIT(30)
    #define CPDMA_DESC_OWNER	BIT(29)
    #define CPDMA_DESC_EOQ		BIT(28)
    
    /*
     * This timeout definition is a worst-case ultra defensive measure against
     * unexpected controller lock ups.  Ideally, we should never ever hit this
     * scenario in practice.
     */
    #define MDIO_TIMEOUT            100 /* msecs */
    #define CPDMA_TIMEOUT		100 /* msecs */
    
    struct cpsw_mdio_regs {
    	u32	version;
    	u32	control;
    #define CONTROL_IDLE		BIT(31)
    #define CONTROL_ENABLE		BIT(30)
    
    	u32	alive;
    	u32	link;
    	u32	linkintraw;
    	u32	linkintmasked;
    	u32	__reserved_0[2];
    	u32	userintraw;
    	u32	userintmasked;
    	u32	userintmaskset;
    	u32	userintmaskclr;
    	u32	__reserved_1[20];
    
    	struct {
    		u32		access;
    		u32		physel;
    #define USERACCESS_GO		BIT(31)
    #define USERACCESS_WRITE	BIT(30)
    #define USERACCESS_ACK		BIT(29)
    #define USERACCESS_READ		(0)
    #define USERACCESS_DATA		(0xffff)
    	} user[0];
    };
    
    struct cpsw_regs {
    	u32	id_ver;
    	u32	control;
    	u32	soft_reset;
    	u32	stat_port_en;
    	u32	ptype;
    };
    
    struct cpsw_slave_regs {
    	u32	max_blks;
    	u32	blk_cnt;
    	u32	flow_thresh;
    	u32	port_vlan;
    	u32	tx_pri_map;
    
    #ifdef CONFIG_AM33XX
    
    #elif defined(CONFIG_TI814X)
    	u32	ts_ctl;
    	u32	ts_seq_ltype;
    	u32	ts_vlan;
    #endif
    
    	u32	sa_lo;
    	u32	sa_hi;
    };
    
    struct cpsw_host_regs {
    	u32	max_blks;
    	u32	blk_cnt;
    	u32	flow_thresh;
    	u32	port_vlan;
    	u32	tx_pri_map;
    	u32	cpdma_tx_pri_map;
    	u32	cpdma_rx_chan_map;
    };
    
    struct cpsw_sliver_regs {
    	u32	id_ver;
    	u32	mac_control;
    	u32	mac_status;
    	u32	soft_reset;
    	u32	rx_maxlen;
    	u32	__reserved_0;
    	u32	rx_pause;
    	u32	tx_pause;
    	u32	__reserved_1;
    	u32	rx_pri_map;
    };
    
    #define ALE_ENTRY_BITS		68
    #define ALE_ENTRY_WORDS		DIV_ROUND_UP(ALE_ENTRY_BITS, 32)
    
    /* ALE Registers */
    #define ALE_CONTROL		0x08
    #define ALE_UNKNOWNVLAN		0x18
    #define ALE_TABLE_CONTROL	0x20
    #define ALE_TABLE		0x34
    #define ALE_PORTCTL		0x40
    
    #define ALE_TABLE_WRITE		BIT(31)
    
    #define ALE_TYPE_FREE			0
    #define ALE_TYPE_ADDR			1
    #define ALE_TYPE_VLAN			2
    #define ALE_TYPE_VLAN_ADDR		3
    
    #define ALE_UCAST_PERSISTANT		0
    #define ALE_UCAST_UNTOUCHED		1
    #define ALE_UCAST_OUI			2
    #define ALE_UCAST_TOUCHED		3
    
    #define ALE_MCAST_FWD			0
    #define ALE_MCAST_BLOCK_LEARN_FWD	1
    #define ALE_MCAST_FWD_LEARN		2
    #define ALE_MCAST_FWD_2			3
    
    enum cpsw_ale_port_state {
    	ALE_PORT_STATE_DISABLE	= 0x00,
    	ALE_PORT_STATE_BLOCK	= 0x01,
    	ALE_PORT_STATE_LEARN	= 0x02,
    	ALE_PORT_STATE_FORWARD	= 0x03,
    };
    
    /* ALE unicast entry flags - passed into cpsw_ale_add_ucast() */
    #define ALE_SECURE	1
    #define ALE_BLOCKED	2
    
    struct cpsw_slave {
    	struct cpsw_slave_regs		*regs;
    	struct cpsw_sliver_regs		*sliver;
    	int				slave_num;
    	u32				mac_control;
    	struct cpsw_slave_data		*data;
    };
    
    struct cpdma_desc {
    	/* hardware fields */
    	u32			hw_next;
    	u32			hw_buffer;
    	u32			hw_len;
    	u32			hw_mode;
    	/* software fields */
    	u32			sw_buffer;
    	u32			sw_len;
    };
    
    struct cpdma_chan {
    	struct cpdma_desc	*head, *tail;
    	void			*hdp, *cp, *rxfree;
    };
    
    #define desc_write(desc, fld, val)	__raw_writel((u32)(val), &(desc)->fld)
    #define desc_read(desc, fld)		__raw_readl(&(desc)->fld)
    #define desc_read_ptr(desc, fld)	((void *)__raw_readl(&(desc)->fld))
    
    #define chan_write(chan, fld, val)	__raw_writel((u32)(val), (chan)->fld)
    #define chan_read(chan, fld)		__raw_readl((chan)->fld)
    #define chan_read_ptr(chan, fld)	((void *)__raw_readl((chan)->fld))
    
    #define for_each_slave(slave, priv) \
    	for (slave = (priv)->slaves; slave != (priv)->slaves + \
    				(priv)->data.slaves; slave++)
    
    struct cpsw_priv {
    	struct eth_device		*dev;
    	struct cpsw_platform_data	data;
    	int				host_port;
    
    	struct cpsw_regs		*regs;
    	void				*dma_regs;
    	struct cpsw_host_regs		*host_port_regs;
    	void				*ale_regs;
    
    	struct cpdma_desc		*descs;
    	struct cpdma_desc		*desc_free;
    	struct cpdma_chan		rx_chan, tx_chan;
    
    	struct cpsw_slave		*slaves;
    	struct phy_device		*phydev;
    	struct mii_dev			*bus;
    
    };
    
    static inline int cpsw_ale_get_field(u32 *ale_entry, u32 start, u32 bits)
    {
    	int idx;
    
    	idx    = start / 32;
    	start -= idx * 32;
    	idx    = 2 - idx; /* flip */
    	return (ale_entry[idx] >> start) & BITMASK(bits);
    }
    
    static inline void cpsw_ale_set_field(u32 *ale_entry, u32 start, u32 bits,
    				      u32 value)
    {
    	int idx;
    
    	value &= BITMASK(bits);
    	idx    = start / 32;
    	start -= idx * 32;
    	idx    = 2 - idx; /* flip */
    	ale_entry[idx] &= ~(BITMASK(bits) << start);
    	ale_entry[idx] |=  (value << start);
    }
    
    #define DEFINE_ALE_FIELD(name, start, bits)				\
    static inline int cpsw_ale_get_##name(u32 *ale_entry)			\
    {									\
    	return cpsw_ale_get_field(ale_entry, start, bits);		\
    }									\
    static inline void cpsw_ale_set_##name(u32 *ale_entry, u32 value)	\
    {									\
    	cpsw_ale_set_field(ale_entry, start, bits, value);		\
    }
    
    DEFINE_ALE_FIELD(entry_type,		60,	2)
    DEFINE_ALE_FIELD(mcast_state,		62,	2)
    DEFINE_ALE_FIELD(port_mask,		66,	3)
    DEFINE_ALE_FIELD(ucast_type,		62,	2)
    DEFINE_ALE_FIELD(port_num,		66,	2)
    DEFINE_ALE_FIELD(blocked,		65,	1)
    DEFINE_ALE_FIELD(secure,		64,	1)
    DEFINE_ALE_FIELD(mcast,			40,	1)
    
    /* The MAC address field in the ALE entry cannot be macroized as above */
    static inline void cpsw_ale_get_addr(u32 *ale_entry, u8 *addr)
    {
    	int i;
    
    	for (i = 0; i < 6; i++)
    		addr[i] = cpsw_ale_get_field(ale_entry, 40 - 8*i, 8);
    }
    
    static inline void cpsw_ale_set_addr(u32 *ale_entry, u8 *addr)
    {
    	int i;
    
    	for (i = 0; i < 6; i++)
    		cpsw_ale_set_field(ale_entry, 40 - 8*i, 8, addr[i]);
    }
    
    static int cpsw_ale_read(struct cpsw_priv *priv, int idx, u32 *ale_entry)
    {
    	int i;
    
    	__raw_writel(idx, priv->ale_regs + ALE_TABLE_CONTROL);
    
    	for (i = 0; i < ALE_ENTRY_WORDS; i++)
    		ale_entry[i] = __raw_readl(priv->ale_regs + ALE_TABLE + 4 * i);
    
    	return idx;
    }
    
    static int cpsw_ale_write(struct cpsw_priv *priv, int idx, u32 *ale_entry)
    {
    	int i;
    
    	for (i = 0; i < ALE_ENTRY_WORDS; i++)
    		__raw_writel(ale_entry[i], priv->ale_regs + ALE_TABLE + 4 * i);
    
    	__raw_writel(idx | ALE_TABLE_WRITE, priv->ale_regs + ALE_TABLE_CONTROL);
    
    	return idx;
    }
    
    static int cpsw_ale_match_addr(struct cpsw_priv *priv, u8* addr)
    {
    	u32 ale_entry[ALE_ENTRY_WORDS];
    	int type, idx;
    
    	for (idx = 0; idx < priv->data.ale_entries; idx++) {
    		u8 entry_addr[6];
    
    		cpsw_ale_read(priv, idx, ale_entry);
    		type = cpsw_ale_get_entry_type(ale_entry);
    		if (type != ALE_TYPE_ADDR && type != ALE_TYPE_VLAN_ADDR)
    			continue;
    		cpsw_ale_get_addr(ale_entry, entry_addr);
    		if (memcmp(entry_addr, addr, 6) == 0)
    			return idx;
    	}
    	return -ENOENT;
    }
    
    static int cpsw_ale_match_free(struct cpsw_priv *priv)
    {
    	u32 ale_entry[ALE_ENTRY_WORDS];
    	int type, idx;
    
    	for (idx = 0; idx < priv->data.ale_entries; idx++) {
    		cpsw_ale_read(priv, idx, ale_entry);
    		type = cpsw_ale_get_entry_type(ale_entry);
    		if (type == ALE_TYPE_FREE)
    			return idx;
    	}
    	return -ENOENT;
    }
    
    static int cpsw_ale_find_ageable(struct cpsw_priv *priv)
    {
    	u32 ale_entry[ALE_ENTRY_WORDS];
    	int type, idx;
    
    	for (idx = 0; idx < priv->data.ale_entries; idx++) {
    		cpsw_ale_read(priv, idx, ale_entry);
    		type = cpsw_ale_get_entry_type(ale_entry);
    		if (type != ALE_TYPE_ADDR && type != ALE_TYPE_VLAN_ADDR)
    			continue;
    		if (cpsw_ale_get_mcast(ale_entry))
    			continue;
    		type = cpsw_ale_get_ucast_type(ale_entry);
    		if (type != ALE_UCAST_PERSISTANT &&
    		    type != ALE_UCAST_OUI)
    			return idx;
    	}
    	return -ENOENT;
    }
    
    static int cpsw_ale_add_ucast(struct cpsw_priv *priv, u8 *addr,
    			      int port, int flags)
    {
    	u32 ale_entry[ALE_ENTRY_WORDS] = {0, 0, 0};
    	int idx;
    
    	cpsw_ale_set_entry_type(ale_entry, ALE_TYPE_ADDR);
    	cpsw_ale_set_addr(ale_entry, addr);
    	cpsw_ale_set_ucast_type(ale_entry, ALE_UCAST_PERSISTANT);
    	cpsw_ale_set_secure(ale_entry, (flags & ALE_SECURE) ? 1 : 0);
    	cpsw_ale_set_blocked(ale_entry, (flags & ALE_BLOCKED) ? 1 : 0);
    	cpsw_ale_set_port_num(ale_entry, port);
    
    	idx = cpsw_ale_match_addr(priv, addr);
    	if (idx < 0)
    		idx = cpsw_ale_match_free(priv);
    	if (idx < 0)
    		idx = cpsw_ale_find_ageable(priv);
    	if (idx < 0)
    		return -ENOMEM;
    
    	cpsw_ale_write(priv, idx, ale_entry);
    	return 0;
    }
    
    static int cpsw_ale_add_mcast(struct cpsw_priv *priv, u8 *addr, int port_mask)
    {
    	u32 ale_entry[ALE_ENTRY_WORDS] = {0, 0, 0};
    	int idx, mask;
    
    	idx = cpsw_ale_match_addr(priv, addr);
    	if (idx >= 0)
    		cpsw_ale_read(priv, idx, ale_entry);
    
    	cpsw_ale_set_entry_type(ale_entry, ALE_TYPE_ADDR);
    	cpsw_ale_set_addr(ale_entry, addr);
    	cpsw_ale_set_mcast_state(ale_entry, ALE_MCAST_FWD_2);
    
    	mask = cpsw_ale_get_port_mask(ale_entry);
    	port_mask |= mask;
    	cpsw_ale_set_port_mask(ale_entry, port_mask);
    
    	if (idx < 0)
    		idx = cpsw_ale_match_free(priv);
    	if (idx < 0)
    		idx = cpsw_ale_find_ageable(priv);
    	if (idx < 0)
    		return -ENOMEM;
    
    	cpsw_ale_write(priv, idx, ale_entry);
    	return 0;
    }
    
    static inline void cpsw_ale_control(struct cpsw_priv *priv, int bit, int val)
    {
    	u32 tmp, mask = BIT(bit);
    
    	tmp  = __raw_readl(priv->ale_regs + ALE_CONTROL);
    	tmp &= ~mask;
    	tmp |= val ? mask : 0;
    	__raw_writel(tmp, priv->ale_regs + ALE_CONTROL);
    }
    
    #define cpsw_ale_enable(priv, val)	cpsw_ale_control(priv, 31, val)
    #define cpsw_ale_clear(priv, val)	cpsw_ale_control(priv, 30, val)
    #define cpsw_ale_vlan_aware(priv, val)	cpsw_ale_control(priv,  2, val)
    
    static inline void cpsw_ale_port_state(struct cpsw_priv *priv, int port,
    				       int val)
    {
    	int offset = ALE_PORTCTL + 4 * port;
    	u32 tmp, mask = 0x3;
    
    	tmp  = __raw_readl(priv->ale_regs + offset);
    	tmp &= ~mask;
    	tmp |= val & mask;
    	__raw_writel(tmp, priv->ale_regs + offset);
    }
    
    static struct cpsw_mdio_regs *mdio_regs;
    
    /* wait until hardware is ready for another user access */
    static inline u32 wait_for_user_access(void)
    {
    	u32 reg = 0;
    	int timeout = MDIO_TIMEOUT;
    
    	while (timeout-- &&
    	((reg = __raw_readl(&mdio_regs->user[0].access)) & USERACCESS_GO))
    		udelay(10);
    
    	if (timeout == -1) {
    		printf("wait_for_user_access Timeout\n");
    		return -ETIMEDOUT;
    	}
    	return reg;
    }
    
    /* wait until hardware state machine is idle */
    static inline void wait_for_idle(void)
    {
    	int timeout = MDIO_TIMEOUT;
    
    	while (timeout-- &&
    		((__raw_readl(&mdio_regs->control) & CONTROL_IDLE) == 0))
    		udelay(10);
    
    	if (timeout == -1)
    		printf("wait_for_idle Timeout\n");
    }
    
    static int cpsw_mdio_read(struct mii_dev *bus, int phy_id,
    				int dev_addr, int phy_reg)
    {
    	unsigned short data;
    	u32 reg;
    
    	if (phy_reg & ~PHY_REG_MASK || phy_id & ~PHY_ID_MASK)
    		return -EINVAL;
    
    	wait_for_user_access();
    	reg = (USERACCESS_GO | USERACCESS_READ | (phy_reg << 21) |
    	       (phy_id << 16));
    	__raw_writel(reg, &mdio_regs->user[0].access);
    	reg = wait_for_user_access();
    
    	data = (reg & USERACCESS_ACK) ? (reg & USERACCESS_DATA) : -1;
    	return data;
    }
    
    static int cpsw_mdio_write(struct mii_dev *bus, int phy_id, int dev_addr,
    				int phy_reg, u16 data)
    {
    	u32 reg;
    
    	if (phy_reg & ~PHY_REG_MASK || phy_id & ~PHY_ID_MASK)
    		return -EINVAL;
    
    	wait_for_user_access();
    	reg = (USERACCESS_GO | USERACCESS_WRITE | (phy_reg << 21) |
    		   (phy_id << 16) | (data & USERACCESS_DATA));
    	__raw_writel(reg, &mdio_regs->user[0].access);
    	wait_for_user_access();
    
    	return 0;
    }
    
    static void cpsw_mdio_init(char *name, u32 mdio_base, u32 div)
    {
    	struct mii_dev *bus = mdio_alloc();
    
    	mdio_regs = (struct cpsw_mdio_regs *)mdio_base;
    
    	/* set enable and clock divider */
    	__raw_writel(div | CONTROL_ENABLE, &mdio_regs->control);
    
    	/*
    	 * wait for scan logic to settle:
    	 * the scan time consists of (a) a large fixed component, and (b) a
    	 * small component that varies with the mii bus frequency.  These
    	 * were estimated using measurements at 1.1 and 2.2 MHz on tnetv107x
    	 * silicon.  Since the effect of (b) was found to be largely
    	 * negligible, we keep things simple here.
    	 */
    	udelay(1000);
    
    	bus->read = cpsw_mdio_read;
    	bus->write = cpsw_mdio_write;
    	sprintf(bus->name, name);
    
    	mdio_register(bus);
    }
    
    /* Set a self-clearing bit in a register, and wait for it to clear */
    static inline void setbit_and_wait_for_clear32(void *addr)
    {
    	__raw_writel(CLEAR_BIT, addr);
    	while (__raw_readl(addr) & CLEAR_BIT)
    		;
    }
    
    #define mac_hi(mac)	(((mac)[0] << 0) | ((mac)[1] << 8) |	\
    			 ((mac)[2] << 16) | ((mac)[3] << 24))
    #define mac_lo(mac)	(((mac)[4] << 0) | ((mac)[5] << 8))
    
    static void cpsw_set_slave_mac(struct cpsw_slave *slave,
    			       struct cpsw_priv *priv)
    {
    	__raw_writel(mac_hi(priv->dev->enetaddr), &slave->regs->sa_hi);
    	__raw_writel(mac_lo(priv->dev->enetaddr), &slave->regs->sa_lo);
    }
    
    static void cpsw_slave_update_link(struct cpsw_slave *slave,
    				   struct cpsw_priv *priv, int *link)
    {
    	struct phy_device *phy = priv->phydev;
    	u32 mac_control = 0;
    
    	phy_startup(phy);
    	*link = phy->link;
    
    	if (*link) { /* link up */
    		mac_control = priv->data.mac_control;
    		if (phy->speed == 1000)
    			mac_control |= GIGABITEN;
    		if (phy->duplex == DUPLEX_FULL)
    			mac_control |= FULLDUPLEXEN;
    		if (phy->speed == 100)
    			mac_control |= MIIEN;
    	}
    
    	if (mac_control == slave->mac_control)
    		return;
    
    	if (mac_control) {
    		printf("link up on port %d, speed %d, %s duplex\n",
    				slave->slave_num, phy->speed,
    				(phy->duplex == DUPLEX_FULL) ? "full" : "half");
    	} else {
    		printf("link down on port %d\n", slave->slave_num);
    	}
    
    	__raw_writel(mac_control, &slave->sliver->mac_control);
    	slave->mac_control = mac_control;
    }
    
    static int cpsw_update_link(struct cpsw_priv *priv)
    {
    	int link = 0;
    	struct cpsw_slave *slave;
    
    	for_each_slave(slave, priv)
    		cpsw_slave_update_link(slave, priv, &link);
    
    	priv->mdio_link = readl(&mdio_regs->link);
    
    static int cpsw_check_link(struct cpsw_priv *priv)
    {
    	u32 link = 0;
    
    	link = __raw_readl(&mdio_regs->link) & priv->phy_mask;
    	if ((link) && (link == priv->mdio_link))
    		return 1;
    
    	return cpsw_update_link(priv);
    }
    
    
    static inline u32  cpsw_get_slave_port(struct cpsw_priv *priv, u32 slave_num)
    {
    	if (priv->host_port == 0)
    		return slave_num + 1;
    	else
    		return slave_num;
    }
    
    static void cpsw_slave_init(struct cpsw_slave *slave, struct cpsw_priv *priv)
    {
    	u32     slave_port;
    
    	setbit_and_wait_for_clear32(&slave->sliver->soft_reset);
    
    	/* setup priority mapping */
    	__raw_writel(0x76543210, &slave->sliver->rx_pri_map);
    	__raw_writel(0x33221100, &slave->regs->tx_pri_map);
    
    	/* setup max packet size, and mac address */
    	__raw_writel(PKT_MAX, &slave->sliver->rx_maxlen);
    	cpsw_set_slave_mac(slave, priv);
    
    	slave->mac_control = 0;	/* no link yet */
    
    	/* enable forwarding */
    	slave_port = cpsw_get_slave_port(priv, slave->slave_num);
    	cpsw_ale_port_state(priv, slave_port, ALE_PORT_STATE_FORWARD);
    
    	cpsw_ale_add_mcast(priv, NetBcastAddr, 1 << slave_port);
    
    
    	priv->phy_mask |= 1 << slave->data->phy_id;
    
    }
    
    static struct cpdma_desc *cpdma_desc_alloc(struct cpsw_priv *priv)
    {
    	struct cpdma_desc *desc = priv->desc_free;
    
    	if (desc)
    		priv->desc_free = desc_read_ptr(desc, hw_next);
    	return desc;
    }
    
    static void cpdma_desc_free(struct cpsw_priv *priv, struct cpdma_desc *desc)
    {
    	if (desc) {
    		desc_write(desc, hw_next, priv->desc_free);
    		priv->desc_free = desc;
    	}
    }
    
    static int cpdma_submit(struct cpsw_priv *priv, struct cpdma_chan *chan,
    			void *buffer, int len)
    {
    	struct cpdma_desc *desc, *prev;
    	u32 mode;
    
    	desc = cpdma_desc_alloc(priv);
    	if (!desc)
    		return -ENOMEM;
    
    	if (len < PKT_MIN)
    		len = PKT_MIN;
    
    	mode = CPDMA_DESC_OWNER | CPDMA_DESC_SOP | CPDMA_DESC_EOP;
    
    	desc_write(desc, hw_next,   0);
    	desc_write(desc, hw_buffer, buffer);
    	desc_write(desc, hw_len,    len);
    	desc_write(desc, hw_mode,   mode | len);
    	desc_write(desc, sw_buffer, buffer);
    	desc_write(desc, sw_len,    len);
    
    	if (!chan->head) {
    		/* simple case - first packet enqueued */
    		chan->head = desc;
    		chan->tail = desc;
    		chan_write(chan, hdp, desc);
    		goto done;
    	}
    
    	/* not the first packet - enqueue at the tail */
    	prev = chan->tail;
    	desc_write(prev, hw_next, desc);
    	chan->tail = desc;
    
    	/* next check if EOQ has been triggered already */
    	if (desc_read(prev, hw_mode) & CPDMA_DESC_EOQ)
    		chan_write(chan, hdp, desc);
    
    done:
    	if (chan->rxfree)
    		chan_write(chan, rxfree, 1);
    	return 0;
    }
    
    static int cpdma_process(struct cpsw_priv *priv, struct cpdma_chan *chan,
    			 void **buffer, int *len)
    {
    	struct cpdma_desc *desc = chan->head;
    	u32 status;
    
    	if (!desc)
    		return -ENOENT;
    
    	status = desc_read(desc, hw_mode);
    
    	if (len)
    		*len = status & 0x7ff;
    
    	if (buffer)
    		*buffer = desc_read_ptr(desc, sw_buffer);
    
    	if (status & CPDMA_DESC_OWNER) {
    		if (chan_read(chan, hdp) == 0) {
    			if (desc_read(desc, hw_mode) & CPDMA_DESC_OWNER)
    				chan_write(chan, hdp, desc);
    		}
    
    		return -EBUSY;
    	}
    
    	chan->head = desc_read_ptr(desc, hw_next);
    	chan_write(chan, cp, desc);
    
    	cpdma_desc_free(priv, desc);
    	return 0;
    }
    
    static int cpsw_init(struct eth_device *dev, bd_t *bis)
    {
    	struct cpsw_priv	*priv = dev->priv;
    	struct cpsw_slave	*slave;
    	int i, ret;
    
    	/* soft reset the controller and initialize priv */
    	setbit_and_wait_for_clear32(&priv->regs->soft_reset);
    
    	/* initialize and reset the address lookup engine */
    	cpsw_ale_enable(priv, 1);
    	cpsw_ale_clear(priv, 1);
    	cpsw_ale_vlan_aware(priv, 0); /* vlan unaware mode */
    
    	/* setup host port priority mapping */
    	__raw_writel(0x76543210, &priv->host_port_regs->cpdma_tx_pri_map);
    	__raw_writel(0, &priv->host_port_regs->cpdma_rx_chan_map);
    
    	/* disable priority elevation and enable statistics on all ports */
    	__raw_writel(0, &priv->regs->ptype);
    
    	/* enable statistics collection only on the host port */
    	__raw_writel(BIT(priv->host_port), &priv->regs->stat_port_en);
    
    	cpsw_ale_port_state(priv, priv->host_port, ALE_PORT_STATE_FORWARD);
    
    	cpsw_ale_add_ucast(priv, priv->dev->enetaddr, priv->host_port,
    			   ALE_SECURE);
    	cpsw_ale_add_mcast(priv, NetBcastAddr, 1 << priv->host_port);
    
    	for_each_slave(slave, priv)
    		cpsw_slave_init(slave, priv);
    
    	cpsw_update_link(priv);
    
    	/* init descriptor pool */
    	for (i = 0; i < NUM_DESCS; i++) {
    		desc_write(&priv->descs[i], hw_next,
    			   (i == (NUM_DESCS - 1)) ? 0 : &priv->descs[i+1]);
    	}
    	priv->desc_free = &priv->descs[0];
    
    	/* initialize channels */
    	if (priv->data.version == CPSW_CTRL_VERSION_2) {
    		memset(&priv->rx_chan, 0, sizeof(struct cpdma_chan));
    		priv->rx_chan.hdp       = priv->dma_regs + CPDMA_RXHDP_VER2;
    		priv->rx_chan.cp        = priv->dma_regs + CPDMA_RXCP_VER2;
    		priv->rx_chan.rxfree    = priv->dma_regs + CPDMA_RXFREE;
    
    		memset(&priv->tx_chan, 0, sizeof(struct cpdma_chan));
    		priv->tx_chan.hdp       = priv->dma_regs + CPDMA_TXHDP_VER2;
    		priv->tx_chan.cp        = priv->dma_regs + CPDMA_TXCP_VER2;
    	} else {
    		memset(&priv->rx_chan, 0, sizeof(struct cpdma_chan));
    		priv->rx_chan.hdp       = priv->dma_regs + CPDMA_RXHDP_VER1;
    		priv->rx_chan.cp        = priv->dma_regs + CPDMA_RXCP_VER1;
    		priv->rx_chan.rxfree    = priv->dma_regs + CPDMA_RXFREE;
    
    		memset(&priv->tx_chan, 0, sizeof(struct cpdma_chan));
    		priv->tx_chan.hdp       = priv->dma_regs + CPDMA_TXHDP_VER1;
    		priv->tx_chan.cp        = priv->dma_regs + CPDMA_TXCP_VER1;
    	}
    
    	/* clear dma state */
    	setbit_and_wait_for_clear32(priv->dma_regs + CPDMA_SOFTRESET);
    
    	if (priv->data.version == CPSW_CTRL_VERSION_2) {
    		for (i = 0; i < priv->data.channels; i++) {
    			__raw_writel(0, priv->dma_regs + CPDMA_RXHDP_VER2 + 4
    					* i);
    			__raw_writel(0, priv->dma_regs + CPDMA_RXFREE + 4
    					* i);
    			__raw_writel(0, priv->dma_regs + CPDMA_RXCP_VER2 + 4
    					* i);
    			__raw_writel(0, priv->dma_regs + CPDMA_TXHDP_VER2 + 4
    					* i);
    			__raw_writel(0, priv->dma_regs + CPDMA_TXCP_VER2 + 4
    					* i);
    		}
    	} else {
    		for (i = 0; i < priv->data.channels; i++) {
    			__raw_writel(0, priv->dma_regs + CPDMA_RXHDP_VER1 + 4
    					* i);
    			__raw_writel(0, priv->dma_regs + CPDMA_RXFREE + 4
    					* i);
    			__raw_writel(0, priv->dma_regs + CPDMA_RXCP_VER1 + 4
    					* i);
    			__raw_writel(0, priv->dma_regs + CPDMA_TXHDP_VER1 + 4
    					* i);
    			__raw_writel(0, priv->dma_regs + CPDMA_TXCP_VER1 + 4
    					* i);
    
    		}
    	}
    
    	__raw_writel(1, priv->dma_regs + CPDMA_TXCONTROL);
    	__raw_writel(1, priv->dma_regs + CPDMA_RXCONTROL);
    
    	/* submit rx descs */
    	for (i = 0; i < PKTBUFSRX; i++) {
    		ret = cpdma_submit(priv, &priv->rx_chan, NetRxPackets[i],
    				   PKTSIZE);
    		if (ret < 0) {
    			printf("error %d submitting rx desc\n", ret);
    			break;
    		}
    	}
    
    	return 0;
    }
    
    static void cpsw_halt(struct eth_device *dev)
    {
    	struct cpsw_priv	*priv = dev->priv;
    
    	writel(0, priv->dma_regs + CPDMA_TXCONTROL);
    	writel(0, priv->dma_regs + CPDMA_RXCONTROL);
    
    	/* soft reset the controller and initialize priv */
    	setbit_and_wait_for_clear32(&priv->regs->soft_reset);
    
    	/* clear dma state */
    	setbit_and_wait_for_clear32(priv->dma_regs + CPDMA_SOFTRESET);
    
    	priv->data.control(0);
    }
    
    static int cpsw_send(struct eth_device *dev, void *packet, int length)
    {
    	struct cpsw_priv	*priv = dev->priv;
    	void *buffer;
    	int len;
    	int timeout = CPDMA_TIMEOUT;
    
    
    		return -EIO;
    
    	flush_dcache_range((unsigned long)packet,
    			   (unsigned long)packet + length);
    
    	/* first reap completed packets */
    	while (timeout-- &&
    		(cpdma_process(priv, &priv->tx_chan, &buffer, &len) >= 0))
    		;
    
    	if (timeout == -1) {
    		printf("cpdma_process timeout\n");
    		return -ETIMEDOUT;
    	}
    
    	return cpdma_submit(priv, &priv->tx_chan, packet, length);
    }
    
    static int cpsw_recv(struct eth_device *dev)
    {
    	struct cpsw_priv	*priv = dev->priv;
    	void *buffer;
    	int len;
    
    	cpsw_update_link(priv);
    
    	while (cpdma_process(priv, &priv->rx_chan, &buffer, &len) >= 0) {
    		invalidate_dcache_range((unsigned long)buffer,
    					(unsigned long)buffer + PKTSIZE_ALIGN);
    		NetReceive(buffer, len);
    		cpdma_submit(priv, &priv->rx_chan, buffer, PKTSIZE);
    	}
    
    	return 0;
    }
    
    static void cpsw_slave_setup(struct cpsw_slave *slave, int slave_num,
    			    struct cpsw_priv *priv)
    {
    	void			*regs = priv->regs;
    	struct cpsw_slave_data	*data = priv->data.slave_data + slave_num;
    	slave->slave_num = slave_num;
    	slave->data	= data;
    	slave->regs	= regs + data->slave_reg_ofs;
    	slave->sliver	= regs + data->sliver_reg_ofs;
    }
    
    static int cpsw_phy_init(struct eth_device *dev, struct cpsw_slave *slave)
    {
    	struct cpsw_priv *priv = (struct cpsw_priv *)dev->priv;
    	struct phy_device *phydev;
    	u32 supported = (SUPPORTED_10baseT_Half |
    			SUPPORTED_10baseT_Full |
    			SUPPORTED_100baseT_Half |
    			SUPPORTED_100baseT_Full |
    			SUPPORTED_1000baseT_Full);
    
    
    	phydev = phy_connect(priv->bus,
    			CONFIG_PHY_ADDR,
    			dev,
    			slave->data->phy_if);
    
    
    	phydev->supported &= supported;
    	phydev->advertising = phydev->supported;
    
    	priv->phydev = phydev;
    	phy_config(phydev);
    
    	return 1;
    }
    
    int cpsw_register(struct cpsw_platform_data *data)
    {
    	struct cpsw_priv	*priv;
    	struct cpsw_slave	*slave;
    	void			*regs = (void *)data->cpsw_base;
    	struct eth_device	*dev;
    
    	dev = calloc(sizeof(*dev), 1);
    	if (!dev)
    		return -ENOMEM;
    
    	priv = calloc(sizeof(*priv), 1);
    	if (!priv) {
    		free(dev);
    		return -ENOMEM;
    	}
    
    	priv->data = *data;
    	priv->dev = dev;
    
    	priv->slaves = malloc(sizeof(struct cpsw_slave) * data->slaves);
    	if (!priv->slaves) {
    		free(dev);
    		free(priv);
    		return -ENOMEM;
    	}
    
    	priv->descs		= (void *)CPDMA_RAM_ADDR;
    	priv->host_port		= data->host_port_num;
    	priv->regs		= regs;
    	priv->host_port_regs	= regs + data->host_port_reg_ofs;
    	priv->dma_regs		= regs + data->cpdma_reg_ofs;
    	priv->ale_regs		= regs + data->ale_reg_ofs;
    
    	int idx = 0;
    
    	for_each_slave(slave, priv) {
    		cpsw_slave_setup(slave, idx, priv);
    		idx = idx + 1;
    	}