/*
 * Ethernet driver for S6105 on chip network device
 * (c)2008 emlix GmbH http://www.emlix.com
 * Authors:	Oskar Schirmer <oskar@scara.com>
 *		Daniel Gloeckner <dg@emlix.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; either version
 * 2 of the License, or (at your option) any later version.
 */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/types.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/if.h>
#include <linux/stddef.h>
#include <linux/mii.h>
#include <linux/phy.h>
#include <linux/platform_device.h>
#include <variant/hardware.h>
#include <variant/dmac.h>

#define DRV_NAME "s6gmac"
#define DRV_PRMT DRV_NAME ": "


/* register declarations */

#define S6_GMAC_MACCONF1	0x000
#define S6_GMAC_MACCONF1_TXENA		0
#define S6_GMAC_MACCONF1_SYNCTX		1
#define S6_GMAC_MACCONF1_RXENA		2
#define S6_GMAC_MACCONF1_SYNCRX		3
#define S6_GMAC_MACCONF1_TXFLOWCTRL	4
#define S6_GMAC_MACCONF1_RXFLOWCTRL	5
#define S6_GMAC_MACCONF1_LOOPBACK	8
#define S6_GMAC_MACCONF1_RESTXFUNC	16
#define S6_GMAC_MACCONF1_RESRXFUNC	17
#define S6_GMAC_MACCONF1_RESTXMACCTRL	18
#define S6_GMAC_MACCONF1_RESRXMACCTRL	19
#define S6_GMAC_MACCONF1_SIMULRES	30
#define S6_GMAC_MACCONF1_SOFTRES	31
#define S6_GMAC_MACCONF2	0x004
#define S6_GMAC_MACCONF2_FULL		0
#define S6_GMAC_MACCONF2_CRCENA		1
#define S6_GMAC_MACCONF2_PADCRCENA	2
#define S6_GMAC_MACCONF2_LENGTHFCHK	4
#define S6_GMAC_MACCONF2_HUGEFRAMENA	5
#define S6_GMAC_MACCONF2_IFMODE		8
#define S6_GMAC_MACCONF2_IFMODE_NIBBLE		1
#define S6_GMAC_MACCONF2_IFMODE_BYTE		2
#define S6_GMAC_MACCONF2_IFMODE_MASK		3
#define S6_GMAC_MACCONF2_PREAMBLELEN	12
#define S6_GMAC_MACCONF2_PREAMBLELEN_MASK	0x0F
#define S6_GMAC_MACIPGIFG	0x008
#define S6_GMAC_MACIPGIFG_B2BINTERPGAP	0
#define S6_GMAC_MACIPGIFG_B2BINTERPGAP_MASK	0x7F
#define S6_GMAC_MACIPGIFG_MINIFGENFORCE	8
#define S6_GMAC_MACIPGIFG_B2BINTERPGAP2	16
#define S6_GMAC_MACIPGIFG_B2BINTERPGAP1	24
#define S6_GMAC_MACHALFDUPLEX	0x00C
#define S6_GMAC_MACHALFDUPLEX_COLLISWIN	0
#define S6_GMAC_MACHALFDUPLEX_COLLISWIN_MASK	0x3F
#define S6_GMAC_MACHALFDUPLEX_RETXMAX	12
#define S6_GMAC_MACHALFDUPLEX_RETXMAX_MASK	0x0F
#define S6_GMAC_MACHALFDUPLEX_EXCESSDEF	16
#define S6_GMAC_MACHALFDUPLEX_NOBACKOFF	17
#define S6_GMAC_MACHALFDUPLEX_BPNOBCKOF	18
#define S6_GMAC_MACHALFDUPLEX_ALTBEBENA	19
#define S6_GMAC_MACHALFDUPLEX_ALTBEBTRN	20
#define S6_GMAC_MACHALFDUPLEX_ALTBEBTR_MASK	0x0F
#define S6_GMAC_MACMAXFRAMELEN	0x010
#define S6_GMAC_MACMIICONF	0x020
#define S6_GMAC_MACMIICONF_CSEL		0
#define S6_GMAC_MACMIICONF_CSEL_DIV10		0
#define S6_GMAC_MACMIICONF_CSEL_DIV12		1
#define S6_GMAC_MACMIICONF_CSEL_DIV14		2
#define S6_GMAC_MACMIICONF_CSEL_DIV18		3
#define S6_GMAC_MACMIICONF_CSEL_DIV24		4
#define S6_GMAC_MACMIICONF_CSEL_DIV34		5
#define S6_GMAC_MACMIICONF_CSEL_DIV68		6
#define S6_GMAC_MACMIICONF_CSEL_DIV168		7
#define S6_GMAC_MACMIICONF_CSEL_MASK		7
#define S6_GMAC_MACMIICONF_PREAMBLESUPR	4
#define S6_GMAC_MACMIICONF_SCANAUTOINCR	5
#define S6_GMAC_MACMIICMD	0x024
#define S6_GMAC_MACMIICMD_READ		0
#define S6_GMAC_MACMIICMD_SCAN		1
#define S6_GMAC_MACMIIADDR	0x028
#define S6_GMAC_MACMIIADDR_REG		0
#define S6_GMAC_MACMIIADDR_REG_MASK		0x1F
#define S6_GMAC_MACMIIADDR_PHY		8
#define S6_GMAC_MACMIIADDR_PHY_MASK		0x1F
#define S6_GMAC_MACMIICTRL	0x02C
#define S6_GMAC_MACMIISTAT	0x030
#define S6_GMAC_MACMIIINDI	0x034
#define S6_GMAC_MACMIIINDI_BUSY		0
#define S6_GMAC_MACMIIINDI_SCAN		1
#define S6_GMAC_MACMIIINDI_INVAL	2
#define S6_GMAC_MACINTERFSTAT	0x03C
#define S6_GMAC_MACINTERFSTAT_LINKFAIL	3
#define S6_GMAC_MACINTERFSTAT_EXCESSDEF	9
#define S6_GMAC_MACSTATADDR1	0x040
#define S6_GMAC_MACSTATADDR2	0x044

#define S6_GMAC_FIFOCONF0	0x048
#define S6_GMAC_FIFOCONF0_HSTRSTWT	0
#define S6_GMAC_FIFOCONF0_HSTRSTSR	1
#define S6_GMAC_FIFOCONF0_HSTRSTFR	2
#define S6_GMAC_FIFOCONF0_HSTRSTST	3
#define S6_GMAC_FIFOCONF0_HSTRSTFT	4
#define S6_GMAC_FIFOCONF0_WTMENREQ	8
#define S6_GMAC_FIFOCONF0_SRFENREQ	9
#define S6_GMAC_FIFOCONF0_FRFENREQ	10
#define S6_GMAC_FIFOCONF0_STFENREQ	11
#define S6_GMAC_FIFOCONF0_FTFENREQ	12
#define S6_GMAC_FIFOCONF0_WTMENRPLY	16
#define S6_GMAC_FIFOCONF0_SRFENRPLY	17
#define S6_GMAC_FIFOCONF0_FRFENRPLY	18
#define S6_GMAC_FIFOCONF0_STFENRPLY	19
#define S6_GMAC_FIFOCONF0_FTFENRPLY	20
#define S6_GMAC_FIFOCONF1	0x04C
#define S6_GMAC_FIFOCONF2	0x050
#define S6_GMAC_FIFOCONF2_CFGLWM	0
#define S6_GMAC_FIFOCONF2_CFGHWM	16
#define S6_GMAC_FIFOCONF3	0x054
#define S6_GMAC_FIFOCONF3_CFGFTTH	0
#define S6_GMAC_FIFOCONF3_CFGHWMFT	16
#define S6_GMAC_FIFOCONF4	0x058
#define S6_GMAC_FIFOCONF_RSV_PREVDROP	0
#define S6_GMAC_FIFOCONF_RSV_RUNT	1
#define S6_GMAC_FIFOCONF_RSV_FALSECAR	2
#define S6_GMAC_FIFOCONF_RSV_CODEERR	3
#define S6_GMAC_FIFOCONF_RSV_CRCERR	4
#define S6_GMAC_FIFOCONF_RSV_LENGTHERR	5
#define S6_GMAC_FIFOCONF_RSV_LENRANGE	6
#define S6_GMAC_FIFOCONF_RSV_OK		7
#define S6_GMAC_FIFOCONF_RSV_MULTICAST	8
#define S6_GMAC_FIFOCONF_RSV_BROADCAST	9
#define S6_GMAC_FIFOCONF_RSV_DRIBBLE	10
#define S6_GMAC_FIFOCONF_RSV_CTRLFRAME	11
#define S6_GMAC_FIFOCONF_RSV_PAUSECTRL	12
#define S6_GMAC_FIFOCONF_RSV_UNOPCODE	13
#define S6_GMAC_FIFOCONF_RSV_VLANTAG	14
#define S6_GMAC_FIFOCONF_RSV_LONGEVENT	15
#define S6_GMAC_FIFOCONF_RSV_TRUNCATED	16
#define S6_GMAC_FIFOCONF_RSV_MASK		0x3FFFF
#define S6_GMAC_FIFOCONF5	0x05C
#define S6_GMAC_FIFOCONF5_DROPLT64	18
#define S6_GMAC_FIFOCONF5_CFGBYTM	19
#define S6_GMAC_FIFOCONF5_RXDROPSIZE	20
#define S6_GMAC_FIFOCONF5_RXDROPSIZE_MASK	0xF

#define S6_GMAC_STAT_REGS	0x080
#define S6_GMAC_STAT_SIZE_MIN		12
#define S6_GMAC_STATTR64	0x080
#define S6_GMAC_STATTR64_SIZE		18
#define S6_GMAC_STATTR127	0x084
#define S6_GMAC_STATTR127_SIZE		18
#define S6_GMAC_STATTR255	0x088
#define S6_GMAC_STATTR255_SIZE		18
#define S6_GMAC_STATTR511	0x08C
#define S6_GMAC_STATTR511_SIZE		18
#define S6_GMAC_STATTR1K	0x090
#define S6_GMAC_STATTR1K_SIZE		18
#define S6_GMAC_STATTRMAX	0x094
#define S6_GMAC_STATTRMAX_SIZE		18
#define S6_GMAC_STATTRMGV	0x098
#define S6_GMAC_STATTRMGV_SIZE		18
#define S6_GMAC_STATRBYT	0x09C
#define S6_GMAC_STATRBYT_SIZE		24
#define S6_GMAC_STATRPKT	0x0A0
#define S6_GMAC_STATRPKT_SIZE		18
#define S6_GMAC_STATRFCS	0x0A4
#define S6_GMAC_STATRFCS_SIZE		12
#define S6_GMAC_STATRMCA	0x0A8
#define S6_GMAC_STATRMCA_SIZE		18
#define S6_GMAC_STATRBCA	0x0AC
#define S6_GMAC_STATRBCA_SIZE		22
#define S6_GMAC_STATRXCF	0x0B0
#define S6_GMAC_STATRXCF_SIZE		18
#define S6_GMAC_STATRXPF	0x0B4
#define S6_GMAC_STATRXPF_SIZE		12
#define S6_GMAC_STATRXUO	0x0B8
#define S6_GMAC_STATRXUO_SIZE		12
#define S6_GMAC_STATRALN	0x0BC
#define S6_GMAC_STATRALN_SIZE		12
#define S6_GMAC_STATRFLR	0x0C0
#define S6_GMAC_STATRFLR_SIZE		16
#define S6_GMAC_STATRCDE	0x0C4
#define S6_GMAC_STATRCDE_SIZE		12
#define S6_GMAC_STATRCSE	0x0C8
#define S6_GMAC_STATRCSE_SIZE		12
#define S6_GMAC_STATRUND	0x0CC
#define S6_GMAC_STATRUND_SIZE		12
#define S6_GMAC_STATROVR	0x0D0
#define S6_GMAC_STATROVR_SIZE		12
#define S6_GMAC_STATRFRG	0x0D4
#define S6_GMAC_STATRFRG_SIZE		12
#define S6_GMAC_STATRJBR	0x0D8
#define S6_GMAC_STATRJBR_SIZE		12
#define S6_GMAC_STATRDRP	0x0DC
#define S6_GMAC_STATRDRP_SIZE		12
#define S6_GMAC_STATTBYT	0x0E0
#define S6_GMAC_STATTBYT_SIZE		24
#define S6_GMAC_STATTPKT	0x0E4
#define S6_GMAC_STATTPKT_SIZE		18
#define S6_GMAC_STATTMCA	0x0E8
#define S6_GMAC_STATTMCA_SIZE		18
#define S6_GMAC_STATTBCA	0x0EC
#define S6_GMAC_STATTBCA_SIZE		18
#define S6_GMAC_STATTXPF	0x0F0
#define S6_GMAC_STATTXPF_SIZE		12
#define S6_GMAC_STATTDFR	0x0F4
#define S6_GMAC_STATTDFR_SIZE		12
#define S6_GMAC_STATTEDF	0x0F8
#define S6_GMAC_STATTEDF_SIZE		12
#define S6_GMAC_STATTSCL	0x0FC
#define S6_GMAC_STATTSCL_SIZE		12
#define S6_GMAC_STATTMCL	0x100
#define S6_GMAC_STATTMCL_SIZE		12
#define S6_GMAC_STATTLCL	0x104
#define S6_GMAC_STATTLCL_SIZE		12
#define S6_GMAC_STATTXCL	0x108
#define S6_GMAC_STATTXCL_SIZE		12
#define S6_GMAC_STATTNCL	0x10C
#define S6_GMAC_STATTNCL_SIZE		13
#define S6_GMAC_STATTPFH	0x110
#define S6_GMAC_STATTPFH_SIZE		12
#define S6_GMAC_STATTDRP	0x114
#define S6_GMAC_STATTDRP_SIZE		12
#define S6_GMAC_STATTJBR	0x118
#define S6_GMAC_STATTJBR_SIZE		12
#define S6_GMAC_STATTFCS	0x11C
#define S6_GMAC_STATTFCS_SIZE		12
#define S6_GMAC_STATTXCF	0x120
#define S6_GMAC_STATTXCF_SIZE		12
#define S6_GMAC_STATTOVR	0x124
#define S6_GMAC_STATTOVR_SIZE		12
#define S6_GMAC_STATTUND	0x128
#define S6_GMAC_STATTUND_SIZE		12
#define S6_GMAC_STATTFRG	0x12C
#define S6_GMAC_STATTFRG_SIZE		12
#define S6_GMAC_STATCARRY(n)	(0x130 + 4*(n))
#define S6_GMAC_STATCARRYMSK(n)	(0x138 + 4*(n))
#define S6_GMAC_STATCARRY1_RDRP		0
#define S6_GMAC_STATCARRY1_RJBR		1
#define S6_GMAC_STATCARRY1_RFRG		2
#define S6_GMAC_STATCARRY1_ROVR		3
#define S6_GMAC_STATCARRY1_RUND		4
#define S6_GMAC_STATCARRY1_RCSE		5
#define S6_GMAC_STATCARRY1_RCDE		6
#define S6_GMAC_STATCARRY1_RFLR		7
#define S6_GMAC_STATCARRY1_RALN		8
#define S6_GMAC_STATCARRY1_RXUO		9
#define S6_GMAC_STATCARRY1_RXPF		10
#define S6_GMAC_STATCARRY1_RXCF		11
#define S6_GMAC_STATCARRY1_RBCA		12
#define S6_GMAC_STATCARRY1_RMCA		13
#define S6_GMAC_STATCARRY1_RFCS		14
#define S6_GMAC_STATCARRY1_RPKT		15
#define S6_GMAC_STATCARRY1_RBYT		16
#define S6_GMAC_STATCARRY1_TRMGV	25
#define S6_GMAC_STATCARRY1_TRMAX	26
#define S6_GMAC_STATCARRY1_TR1K		27
#define S6_GMAC_STATCARRY1_TR511	28
#define S6_GMAC_STATCARRY1_TR255	29
#define S6_GMAC_STATCARRY1_TR127	30
#define S6_GMAC_STATCARRY1_TR64		31
#define S6_GMAC_STATCARRY2_TDRP		0
#define S6_GMAC_STATCARRY2_TPFH		1
#define S6_GMAC_STATCARRY2_TNCL		2
#define S6_GMAC_STATCARRY2_TXCL		3
#define S6_GMAC_STATCARRY2_TLCL		4
#define S6_GMAC_STATCARRY2_TMCL		5
#define S6_GMAC_STATCARRY2_TSCL		6
#define S6_GMAC_STATCARRY2_TEDF		7
#define S6_GMAC_STATCARRY2_TDFR		8
#define S6_GMAC_STATCARRY2_TXPF		9
#define S6_GMAC_STATCARRY2_TBCA		10
#define S6_GMAC_STATCARRY2_TMCA		11
#define S6_GMAC_STATCARRY2_TPKT		12
#define S6_GMAC_STATCARRY2_TBYT		13
#define S6_GMAC_STATCARRY2_TFRG		14
#define S6_GMAC_STATCARRY2_TUND		15
#define S6_GMAC_STATCARRY2_TOVR		16
#define S6_GMAC_STATCARRY2_TXCF		17
#define S6_GMAC_STATCARRY2_TFCS		18
#define S6_GMAC_STATCARRY2_TJBR		19

#define S6_GMAC_HOST_PBLKCTRL	0x140
#define S6_GMAC_HOST_PBLKCTRL_TXENA	0
#define S6_GMAC_HOST_PBLKCTRL_RXENA	1
#define S6_GMAC_HOST_PBLKCTRL_TXSRES	2
#define S6_GMAC_HOST_PBLKCTRL_RXSRES	3
#define S6_GMAC_HOST_PBLKCTRL_TXBSIZ	8
#define S6_GMAC_HOST_PBLKCTRL_RXBSIZ	12
#define S6_GMAC_HOST_PBLKCTRL_SIZ_16		4
#define S6_GMAC_HOST_PBLKCTRL_SIZ_32		5
#define S6_GMAC_HOST_PBLKCTRL_SIZ_64		6
#define S6_GMAC_HOST_PBLKCTRL_SIZ_128		7
#define S6_GMAC_HOST_PBLKCTRL_SIZ_MASK		0xF
#define S6_GMAC_HOST_PBLKCTRL_STATENA	16
#define S6_GMAC_HOST_PBLKCTRL_STATAUTOZ	17
#define S6_GMAC_HOST_PBLKCTRL_STATCLEAR	18
#define S6_GMAC_HOST_PBLKCTRL_RGMII	19
#define S6_GMAC_HOST_INTMASK	0x144
#define S6_GMAC_HOST_INTSTAT	0x148
#define S6_GMAC_HOST_INT_TXBURSTOVER	3
#define S6_GMAC_HOST_INT_TXPREWOVER	4
#define S6_GMAC_HOST_INT_RXBURSTUNDER	5
#define S6_GMAC_HOST_INT_RXPOSTRFULL	6
#define S6_GMAC_HOST_INT_RXPOSTRUNDER	7
#define S6_GMAC_HOST_RXFIFOHWM	0x14C
#define S6_GMAC_HOST_CTRLFRAMXP	0x150
#define S6_GMAC_HOST_DSTADDRLO(n) (0x160 + 8*(n))
#define S6_GMAC_HOST_DSTADDRHI(n) (0x164 + 8*(n))
#define S6_GMAC_HOST_DSTMASKLO(n) (0x180 + 8*(n))
#define S6_GMAC_HOST_DSTMASKHI(n) (0x184 + 8*(n))

#define S6_GMAC_BURST_PREWR	0x1B0
#define S6_GMAC_BURST_PREWR_LEN		0
#define S6_GMAC_BURST_PREWR_LEN_MASK		((1 << 20) - 1)
#define S6_GMAC_BURST_PREWR_CFE		20
#define S6_GMAC_BURST_PREWR_PPE		21
#define S6_GMAC_BURST_PREWR_FCS		22
#define S6_GMAC_BURST_PREWR_PAD		23
#define S6_GMAC_BURST_POSTRD	0x1D0
#define S6_GMAC_BURST_POSTRD_LEN	0
#define S6_GMAC_BURST_POSTRD_LEN_MASK		((1 << 20) - 1)
#define S6_GMAC_BURST_POSTRD_DROP	20


/* data handling */

#define S6_NUM_TX_SKB	8	/* must be larger than TX fifo size */
#define S6_NUM_RX_SKB	16
#define S6_MAX_FRLEN	1536

struct s6gmac {
	u32 reg;
	u32 tx_dma;
	u32 rx_dma;
	u32 io;
	u8 tx_chan;
	u8 rx_chan;
	spinlock_t lock;
	u8 tx_skb_i, tx_skb_o;
	u8 rx_skb_i, rx_skb_o;
	struct sk_buff *tx_skb[S6_NUM_TX_SKB];
	struct sk_buff *rx_skb[S6_NUM_RX_SKB];
	unsigned long carry[sizeof(struct net_device_stats) / sizeof(long)];
	unsigned long stats[sizeof(struct net_device_stats) / sizeof(long)];
	struct phy_device *phydev;
	struct {
		struct mii_bus *bus;
		int irq[PHY_MAX_ADDR];
	} mii;
	struct {
		unsigned int mbit;
		u8 giga;
		u8 isup;
		u8 full;
	} link;
};

static void s6gmac_rx_fillfifo(struct net_device *dev)
{
	struct s6gmac *pd = netdev_priv(dev);
	struct sk_buff *skb;
	while ((((u8)(pd->rx_skb_i - pd->rx_skb_o)) < S6_NUM_RX_SKB) &&
	       (!s6dmac_fifo_full(pd->rx_dma, pd->rx_chan)) &&
	       (skb = netdev_alloc_skb(dev, S6_MAX_FRLEN + 2))) {
		pd->rx_skb[(pd->rx_skb_i++) % S6_NUM_RX_SKB] = skb;
		s6dmac_put_fifo_cache(pd->rx_dma, pd->rx_chan,
			pd->io, (u32)skb->data, S6_MAX_FRLEN);
	}
}

static void s6gmac_rx_interrupt(struct net_device *dev)
{
	struct s6gmac *pd = netdev_priv(dev);
	u32 pfx;
	struct sk_buff *skb;
	while (((u8)(pd->rx_skb_i - pd->rx_skb_o)) >
			s6dmac_pending_count(pd->rx_dma, pd->rx_chan)) {
		skb = pd->rx_skb[(pd->rx_skb_o++) % S6_NUM_RX_SKB];
		pfx = readl(pd->reg + S6_GMAC_BURST_POSTRD);
		if (pfx & (1 << S6_GMAC_BURST_POSTRD_DROP)) {
			dev_kfree_skb_irq(skb);
		} else {
			skb_put(skb, (pfx >> S6_GMAC_BURST_POSTRD_LEN)
				& S6_GMAC_BURST_POSTRD_LEN_MASK);
			skb->protocol = eth_type_trans(skb, dev);
			skb->ip_summed = CHECKSUM_UNNECESSARY;
			netif_rx(skb);
		}
	}
}

static void s6gmac_tx_interrupt(struct net_device *dev)
{
	struct s6gmac *pd = netdev_priv(dev);
	while (((u8)(pd->tx_skb_i - pd->tx_skb_o)) >
			s6dmac_pending_count(pd->tx_dma, pd->tx_chan)) {
		dev_kfree_skb_irq(pd->tx_skb[(pd->tx_skb_o++) % S6_NUM_TX_SKB]);
	}
	if (!s6dmac_fifo_full(pd->tx_dma, pd->tx_chan))
		netif_wake_queue(dev);
}

struct s6gmac_statinf {
	unsigned reg_size : 4; /* 0: unused */
	unsigned reg_off : 6;
	unsigned net_index : 6;
};

#define S6_STATS_B (8 * sizeof(u32))
#define S6_STATS_C(b, r, f) [b] = { \
	BUILD_BUG_ON_ZERO(r##_SIZE < S6_GMAC_STAT_SIZE_MIN) + \
	BUILD_BUG_ON_ZERO((r##_SIZE - (S6_GMAC_STAT_SIZE_MIN - 1)) \
			>= (1<<4)) + \
	r##_SIZE - (S6_GMAC_STAT_SIZE_MIN - 1), \
	BUILD_BUG_ON_ZERO(((unsigned)((r - S6_GMAC_STAT_REGS) / sizeof(u32))) \
			>= ((1<<6)-1)) + \
	(r - S6_GMAC_STAT_REGS) / sizeof(u32), \
	BUILD_BUG_ON_ZERO((offsetof(struct net_device_stats, f)) \
			% sizeof(unsigned long)) + \
	BUILD_BUG_ON_ZERO((((unsigned)(offsetof(struct net_device_stats, f)) \
			/ sizeof(unsigned long)) >= (1<<6))) + \
	BUILD_BUG_ON_ZERO((sizeof(((struct net_device_stats *)0)->f) \
			!= sizeof(unsigned long))) + \
	(offsetof(struct net_device_stats, f)) / sizeof(unsigned long)},

static const struct s6gmac_statinf statinf[2][S6_STATS_B] = { {
	S6_STATS_C(S6_GMAC_STATCARRY1_RBYT, S6_GMAC_STATRBYT, rx_bytes)
	S6_STATS_C(S6_GMAC_STATCARRY1_RPKT, S6_GMAC_STATRPKT, rx_packets)
	S6_STATS_C(S6_GMAC_STATCARRY1_RFCS, S6_GMAC_STATRFCS, rx_crc_errors)
	S6_STATS_C(S6_GMAC_STATCARRY1_RMCA, S6_GMAC_STATRMCA, multicast)
	S6_STATS_C(S6_GMAC_STATCARRY1_RALN, S6_GMAC_STATRALN, rx_frame_errors)
	S6_STATS_C(S6_GMAC_STATCARRY1_RFLR, S6_GMAC_STATRFLR, rx_length_errors)
	S6_STATS_C(S6_GMAC_STATCARRY1_RCDE, S6_GMAC_STATRCDE, rx_missed_errors)
	S6_STATS_C(S6_GMAC_STATCARRY1_RUND, S6_GMAC_STATRUND, rx_length_errors)
	S6_STATS_C(S6_GMAC_STATCARRY1_ROVR, S6_GMAC_STATROVR, rx_length_errors)
	S6_STATS_C(S6_GMAC_STATCARRY1_RFRG, S6_GMAC_STATRFRG, rx_crc_errors)
	S6_STATS_C(S6_GMAC_STATCARRY1_RJBR, S6_GMAC_STATRJBR, rx_crc_errors)
	S6_STATS_C(S6_GMAC_STATCARRY1_RDRP, S6_GMAC_STATRDRP, rx_dropped)
}, {
	S6_STATS_C(S6_GMAC_STATCARRY2_TBYT, S6_GMAC_STATTBYT, tx_bytes)
	S6_STATS_C(S6_GMAC_STATCARRY2_TPKT, S6_GMAC_STATTPKT, tx_packets)
	S6_STATS_C(S6_GMAC_STATCARRY2_TEDF, S6_GMAC_STATTEDF, tx_aborted_errors)
	S6_STATS_C(S6_GMAC_STATCARRY2_TXCL, S6_GMAC_STATTXCL, tx_aborted_errors)
	S6_STATS_C(S6_GMAC_STATCARRY2_TNCL, S6_GMAC_STATTNCL, collisions)
	S6_STATS_C(S6_GMAC_STATCARRY2_TDRP, S6_GMAC_STATTDRP, tx_dropped)
	S6_STATS_C(S6_GMAC_STATCARRY2_TJBR, S6_GMAC_STATTJBR, tx_errors)
	S6_STATS_C(S6_GMAC_STATCARRY2_TFCS, S6_GMAC_STATTFCS, tx_errors)
	S6_STATS_C(S6_GMAC_STATCARRY2_TOVR, S6_GMAC_STATTOVR, tx_errors)
	S6_STATS_C(S6_GMAC_STATCARRY2_TUND, S6_GMAC_STATTUND, tx_errors)
	S6_STATS_C(S6_GMAC_STATCARRY2_TFRG, S6_GMAC_STATTFRG, tx_errors)
} };

static void s6gmac_stats_collect(struct s6gmac *pd,
		const struct s6gmac_statinf *inf)
{
	int b;
	for (b = 0; b < S6_STATS_B; b++) {
		if (inf[b].reg_size) {
			pd->stats[inf[b].net_index] +=
				readl(pd->reg + S6_GMAC_STAT_REGS
					+ sizeof(u32) * inf[b].reg_off);
		}
	}
}

static void s6gmac_stats_carry(struct s6gmac *pd,
		const struct s6gmac_statinf *inf, u32 mask)
{
	int b;
	while (mask) {
		b = fls(mask) - 1;
		mask &= ~(1 << b);
		pd->carry[inf[b].net_index] += (1 << inf[b].reg_size);
	}
}

static inline u32 s6gmac_stats_pending(struct s6gmac *pd, int carry)
{
	int r = readl(pd->reg + S6_GMAC_STATCARRY(carry)) &
		~readl(pd->reg + S6_GMAC_STATCARRYMSK(carry));
	return r;
}

static inline void s6gmac_stats_interrupt(struct s6gmac *pd, int carry)
{
	u32 mask;
	mask = s6gmac_stats_pending(pd, carry);
	if (mask) {
		writel(mask, pd->reg + S6_GMAC_STATCARRY(carry));
		s6gmac_stats_carry(pd, &statinf[carry][0], mask);
	}
}

static irqreturn_t s6gmac_interrupt(int irq, void *dev_id)
{
	struct net_device *dev = (struct net_device *)dev_id;
	struct s6gmac *pd = netdev_priv(dev);
	if (!dev)
		return IRQ_NONE;
	spin_lock(&pd->lock);
	if (s6dmac_termcnt_irq(pd->rx_dma, pd->rx_chan))
		s6gmac_rx_interrupt(dev);
	s6gmac_rx_fillfifo(dev);
	if (s6dmac_termcnt_irq(pd->tx_dma, pd->tx_chan))
		s6gmac_tx_interrupt(dev);
	s6gmac_stats_interrupt(pd, 0);
	s6gmac_stats_interrupt(pd, 1);
	spin_unlock(&pd->lock);
	return IRQ_HANDLED;
}

static inline void s6gmac_set_dstaddr(struct s6gmac *pd, int n,
	u32 addrlo, u32 addrhi, u32 masklo, u32 maskhi)
{
	writel(addrlo, pd->reg + S6_GMAC_HOST_DSTADDRLO(n));
	writel(addrhi, pd->reg + S6_GMAC_HOST_DSTADDRHI(n));
	writel(masklo, pd->reg + S6_GMAC_HOST_DSTMASKLO(n));
	writel(maskhi, pd->reg + S6_GMAC_HOST_DSTMASKHI(n));
}

static inline void s6gmac_stop_device(struct net_device *dev)
{
	struct s6gmac *pd = netdev_priv(dev);
	writel(0, pd->reg + S6_GMAC_MACCONF1);
}

static inline void s6gmac_init_device(struct net_device *dev)
{
	struct s6gmac *pd = netdev_priv(dev);
	int is_rgmii = !!(pd->phydev->supported
		& (SUPPORTED_1000baseT_Full | SUPPORTED_1000baseT_Half));
#if 0
	writel(1 << S6_GMAC_MACCONF1_SYNCTX |
		1 << S6_GMAC_MACCONF1_SYNCRX |
		1 << S6_GMAC_MACCONF1_TXFLOWCTRL |
		1 << S6_GMAC_MACCONF1_RXFLOWCTRL |
		1 << S6_GMAC_MACCONF1_RESTXFUNC |
		1 << S6_GMAC_MACCONF1_RESRXFUNC |
		1 << S6_GMAC_MACCONF1_RESTXMACCTRL |
		1 << S6_GMAC_MACCONF1_RESRXMACCTRL,
		pd->reg + S6_GMAC_MACCONF1);
#endif
	writel(1 << S6_GMAC_MACCONF1_SOFTRES, pd->reg + S6_GMAC_MACCONF1);
	udelay(1000);
	writel(1 << S6_GMAC_MACCONF1_TXENA | 1 << S6_GMAC_MACCONF1_RXENA,
		pd->reg + S6_GMAC_MACCONF1);
	writel(1 << S6_GMAC_HOST_PBLKCTRL_TXSRES |
		1 << S6_GMAC_HOST_PBLKCTRL_RXSRES,
		pd->reg + S6_GMAC_HOST_PBLKCTRL);
	writel(S6_GMAC_HOST_PBLKCTRL_SIZ_128 << S6_GMAC_HOST_PBLKCTRL_TXBSIZ |
		S6_GMAC_HOST_PBLKCTRL_SIZ_128 << S6_GMAC_HOST_PBLKCTRL_RXBSIZ |
		1 << S6_GMAC_HOST_PBLKCTRL_STATENA |
		1 << S6_GMAC_HOST_PBLKCTRL_STATCLEAR |
		is_rgmii << S6_GMAC_HOST_PBLKCTRL_RGMII,
		pd->reg + S6_GMAC_HOST_PBLKCTRL);
	writel(1 << S6_GMAC_MACCONF1_TXENA |
		1 << S6_GMAC_MACCONF1_RXENA |
		(dev->flags & IFF_LOOPBACK ? 1 : 0)
			<< S6_GMAC_MACCONF1_LOOPBACK,
		pd->reg + S6_GMAC_MACCONF1);
	writel(dev->mtu && (dev->mtu < (S6_MAX_FRLEN - ETH_HLEN-ETH_FCS_LEN)) ?
			dev->mtu+ETH_HLEN+ETH_FCS_LEN : S6_MAX_FRLEN,
		pd->reg + S6_GMAC_MACMAXFRAMELEN);
	writel((pd->link.full ? 1 : 0) << S6_GMAC_MACCONF2_FULL |
		1 << S6_GMAC_MACCONF2_PADCRCENA |
		1 << S6_GMAC_MACCONF2_LENGTHFCHK |
		(pd->link.giga ?
			S6_GMAC_MACCONF2_IFMODE_BYTE :
			S6_GMAC_MACCONF2_IFMODE_NIBBLE)
			<< S6_GMAC_MACCONF2_IFMODE |
		7 << S6_GMAC_MACCONF2_PREAMBLELEN,
		pd->reg + S6_GMAC_MACCONF2);
	writel(0, pd->reg + S6_GMAC_MACSTATADDR1);
	writel(0, pd->reg + S6_GMAC_MACSTATADDR2);
	writel(1 << S6_GMAC_FIFOCONF0_WTMENREQ |
		1 << S6_GMAC_FIFOCONF0_SRFENREQ |
		1 << S6_GMAC_FIFOCONF0_FRFENREQ |
		1 << S6_GMAC_FIFOCONF0_STFENREQ |
		1 << S6_GMAC_FIFOCONF0_FTFENREQ,
		pd->reg + S6_GMAC_FIFOCONF0);
	writel(128 << S6_GMAC_FIFOCONF3_CFGFTTH |
		128 << S6_GMAC_FIFOCONF3_CFGHWMFT,
		pd->reg + S6_GMAC_FIFOCONF3);
	writel((S6_GMAC_FIFOCONF_RSV_MASK & ~(
			1 << S6_GMAC_FIFOCONF_RSV_RUNT |
			1 << S6_GMAC_FIFOCONF_RSV_CRCERR |
			1 << S6_GMAC_FIFOCONF_RSV_OK |
			1 << S6_GMAC_FIFOCONF_RSV_DRIBBLE |
			1 << S6_GMAC_FIFOCONF_RSV_CTRLFRAME |
			1 << S6_GMAC_FIFOCONF_RSV_PAUSECTRL |
			1 << S6_GMAC_FIFOCONF_RSV_UNOPCODE |
			1 << S6_GMAC_FIFOCONF_RSV_TRUNCATED)) |
		1 << S6_GMAC_FIFOCONF5_DROPLT64 |
		pd->link.giga << S6_GMAC_FIFOCONF5_CFGBYTM |
		1 << S6_GMAC_FIFOCONF5_RXDROPSIZE,
		pd->reg + S6_GMAC_FIFOCONF5);
	writel(1 << S6_GMAC_FIFOCONF_RSV_RUNT |
		1 << S6_GMAC_FIFOCONF_RSV_CRCERR |
		1 << S6_GMAC_FIFOCONF_RSV_DRIBBLE |
		1 << S6_GMAC_FIFOCONF_RSV_CTRLFRAME |
		1 << S6_GMAC_FIFOCONF_RSV_PAUSECTRL |
		1 << S6_GMAC_FIFOCONF_RSV_UNOPCODE |
		1 << S6_GMAC_FIFOCONF_RSV_TRUNCATED,
		pd->reg + S6_GMAC_FIFOCONF4);
	s6gmac_set_dstaddr(pd, 0,
		0xFFFFFFFF, 0x0000FFFF, 0xFFFFFFFF, 0x0000FFFF);
	s6gmac_set_dstaddr(pd, 1,
		dev->dev_addr[5] |
		dev->dev_addr[4] << 8 |
		dev->dev_addr[3] << 16 |
		dev->dev_addr[2] << 24,
		dev->dev_addr[1] |
		dev->dev_addr[0] << 8,
		0xFFFFFFFF, 0x0000FFFF);
	s6gmac_set_dstaddr(pd, 2,
		0x00000000, 0x00000100, 0x00000000, 0x00000100);
	s6gmac_set_dstaddr(pd, 3,
		0x00000000, 0x00000000, 0x00000000, 0x00000000);
	writel(1 << S6_GMAC_HOST_PBLKCTRL_TXENA |
		1 << S6_GMAC_HOST_PBLKCTRL_RXENA |
		S6_GMAC_HOST_PBLKCTRL_SIZ_128 << S6_GMAC_HOST_PBLKCTRL_TXBSIZ |
		S6_GMAC_HOST_PBLKCTRL_SIZ_128 << S6_GMAC_HOST_PBLKCTRL_RXBSIZ |
		1 << S6_GMAC_HOST_PBLKCTRL_STATENA |
		1 << S6_GMAC_HOST_PBLKCTRL_STATCLEAR |
		is_rgmii << S6_GMAC_HOST_PBLKCTRL_RGMII,
		pd->reg + S6_GMAC_HOST_PBLKCTRL);
}

static void s6mii_enable(struct s6gmac *pd)
{
	writel(readl(pd->reg + S6_GMAC_MACCONF1) &
		~(1 << S6_GMAC_MACCONF1_SOFTRES),
		pd->reg + S6_GMAC_MACCONF1);
	writel((readl(pd->reg + S6_GMAC_MACMIICONF)
		& ~(S6_GMAC_MACMIICONF_CSEL_MASK << S6_GMAC_MACMIICONF_CSEL))
		| (S6_GMAC_MACMIICONF_CSEL_DIV168 << S6_GMAC_MACMIICONF_CSEL),
		pd->reg + S6_GMAC_MACMIICONF);
}

static int s6mii_busy(struct s6gmac *pd, int tmo)
{
	while (readl(pd->reg + S6_GMAC_MACMIIINDI)) {
		if (--tmo == 0)
			return -ETIME;
		udelay(64);
	}
	return 0;
}

static int s6mii_read(struct mii_bus *bus, int phy_addr, int regnum)
{
	struct s6gmac *pd = bus->priv;
	s6mii_enable(pd);
	if (s6mii_busy(pd, 256))
		return -ETIME;
	writel(phy_addr << S6_GMAC_MACMIIADDR_PHY |
		regnum << S6_GMAC_MACMIIADDR_REG,
		pd->reg + S6_GMAC_MACMIIADDR);
	writel(1 << S6_GMAC_MACMIICMD_READ, pd->reg + S6_GMAC_MACMIICMD);
	writel(0, pd->reg + S6_GMAC_MACMIICMD);
	if (s6mii_busy(pd, 256))
		return -ETIME;
	return (u16)readl(pd->reg + S6_GMAC_MACMIISTAT);
}

static int s6mii_write(struct mii_bus *bus, int phy_addr, int regnum, u16 value)
{
	struct s6gmac *pd = bus->priv;
	s6mii_enable(pd);
	if (s6mii_busy(pd, 256))
		return -ETIME;
	writel(phy_addr << S6_GMAC_MACMIIADDR_PHY |
		regnum << S6_GMAC_MACMIIADDR_REG,
		pd->reg + S6_GMAC_MACMIIADDR);
	writel(value, pd->reg + S6_GMAC_MACMIICTRL);
	if (s6mii_busy(pd, 256))
		return -ETIME;
	return 0;
}

static int s6mii_reset(struct mii_bus *bus)
{
	struct s6gmac *pd = bus->priv;
	s6mii_enable(pd);
	if (s6mii_busy(pd, PHY_INIT_TIMEOUT))
		return -ETIME;
	return 0;
}

static void s6gmac_set_rgmii_txclock(struct s6gmac *pd)
{
	u32 pllsel = readl(S6_REG_GREG1 + S6_GREG1_PLLSEL);
	pllsel &= ~(S6_GREG1_PLLSEL_GMAC_MASK << S6_GREG1_PLLSEL_GMAC);
	switch (pd->link.mbit) {
	case 10:
		pllsel |= S6_GREG1_PLLSEL_GMAC_2500KHZ << S6_GREG1_PLLSEL_GMAC;
		break;
	case 100:
		pllsel |= S6_GREG1_PLLSEL_GMAC_25MHZ << S6_GREG1_PLLSEL_GMAC;
		break;
	case 1000:
		pllsel |= S6_GREG1_PLLSEL_GMAC_125MHZ << S6_GREG1_PLLSEL_GMAC;
		break;
	default:
		return;
	}
	writel(pllsel, S6_REG_GREG1 + S6_GREG1_PLLSEL);
}

static inline void s6gmac_linkisup(struct net_device *dev, int isup)
{
	struct s6gmac *pd = netdev_priv(dev);
	struct phy_device *phydev = pd->phydev;

	pd->link.full = phydev->duplex;
	pd->link.giga = (phydev->speed == 1000);
	if (pd->link.mbit != phydev->speed) {
		pd->link.mbit = phydev->speed;
		s6gmac_set_rgmii_txclock(pd);
	}
	pd->link.isup = isup;
	if (isup)
		netif_carrier_on(dev);
	phy_print_status(phydev);
}

static void s6gmac_adjust_link(struct net_device *dev)
{
	struct s6gmac *pd = netdev_priv(dev);
	struct phy_device *phydev = pd->phydev;
	if (pd->link.isup &&
			(!phydev->link ||
			(pd->link.mbit != phydev->speed) ||
			(pd->link.full != phydev->duplex))) {
		pd->link.isup = 0;
		netif_tx_disable(dev);
		if (!phydev->link) {
			netif_carrier_off(dev);
			phy_print_status(phydev);
		}
	}
	if (!pd->link.isup && phydev->link) {
		if (pd->link.full != phydev->duplex) {
			u32 maccfg = readl(pd->reg + S6_GMAC_MACCONF2);
			if (phydev->duplex)
				maccfg |= 1 << S6_GMAC_MACCONF2_FULL;
			else
				maccfg &= ~(1 << S6_GMAC_MACCONF2_FULL);
			writel(maccfg, pd->reg + S6_GMAC_MACCONF2);
		}

		if (pd->link.giga != (phydev->speed == 1000)) {
			u32 fifocfg = readl(pd->reg + S6_GMAC_FIFOCONF5);
			u32 maccfg = readl(pd->reg + S6_GMAC_MACCONF2);
			maccfg &= ~(S6_GMAC_MACCONF2_IFMODE_MASK
				     << S6_GMAC_MACCONF2_IFMODE);
			if (phydev->speed == 1000) {
				fifocfg |= 1 << S6_GMAC_FIFOCONF5_CFGBYTM;
				maccfg |= S6_GMAC_MACCONF2_IFMODE_BYTE
					   << S6_GMAC_MACCONF2_IFMODE;
			} else {
				fifocfg &= ~(1 << S6_GMAC_FIFOCONF5_CFGBYTM);
				maccfg |= S6_GMAC_MACCONF2_IFMODE_NIBBLE
					   << S6_GMAC_MACCONF2_IFMODE;
			}
			writel(fifocfg, pd->reg + S6_GMAC_FIFOCONF5);
			writel(maccfg, pd->reg + S6_GMAC_MACCONF2);
		}

		if (!s6dmac_fifo_full(pd->tx_dma, pd->tx_chan))
			netif_wake_queue(dev);
		s6gmac_linkisup(dev, 1);
	}
}

static inline int s6gmac_phy_start(struct net_device *dev)
{
	struct s6gmac *pd = netdev_priv(dev);
	int i = 0;
	struct phy_device *p = NULL;
	while ((i < PHY_MAX_ADDR) && (!(p = pd->mii.bus->phy_map[i])))
		i++;
	p = phy_connect(dev, dev_name(&p->dev), &s6gmac_adjust_link, 0,
			PHY_INTERFACE_MODE_RGMII);
	if (IS_ERR(p)) {
		printk(KERN_ERR "%s: Could not attach to PHY\n", dev->name);
		return PTR_ERR(p);
	}
	p->supported &= PHY_GBIT_FEATURES;
	p->advertising = p->supported;
	pd->phydev = p;
	return 0;
}

static inline void s6gmac_init_stats(struct net_device *dev)
{
	struct s6gmac *pd = netdev_priv(dev);
	u32 mask;
	mask =	1 << S6_GMAC_STATCARRY1_RDRP |
		1 << S6_GMAC_STATCARRY1_RJBR |
		1 << S6_GMAC_STATCARRY1_RFRG |
		1 << S6_GMAC_STATCARRY1_ROVR |
		1 << S6_GMAC_STATCARRY1_RUND |
		1 << S6_GMAC_STATCARRY1_RCDE |
		1 << S6_GMAC_STATCARRY1_RFLR |
		1 << S6_GMAC_STATCARRY1_RALN |
		1 << S6_GMAC_STATCARRY1_RMCA |
		1 << S6_GMAC_STATCARRY1_RFCS |
		1 << S6_GMAC_STATCARRY1_RPKT |
		1 << S6_GMAC_STATCARRY1_RBYT;
	writel(mask, pd->reg + S6_GMAC_STATCARRY(0));
	writel(~mask, pd->reg + S6_GMAC_STATCARRYMSK(0));
	mask =	1 << S6_GMAC_STATCARRY2_TDRP |
		1 << S6_GMAC_STATCARRY2_TNCL |
		1 << S6_GMAC_STATCARRY2_TXCL |
		1 << S6_GMAC_STATCARRY2_TEDF |
		1 << S6_GMAC_STATCARRY2_TPKT |
		1 << S6_GMAC_STATCARRY2_TBYT |
		1 << S6_GMAC_STATCARRY2_TFRG |
		1 << S6_GMAC_STATCARRY2_TUND |
		1 << S6_GMAC_STATCARRY2_TOVR |
		1 << S6_GMAC_STATCARRY2_TFCS |
		1 << S6_GMAC_STATCARRY2_TJBR;
	writel(mask, pd->reg + S6_GMAC_STATCARRY(1));
	writel(~mask, pd->reg + S6_GMAC_STATCARRYMSK(1));
}

static inline void s6gmac_init_dmac(struct net_device *dev)
{
	struct s6gmac *pd = netdev_priv(dev);
	s6dmac_disable_chan(pd->tx_dma, pd->tx_chan);
	s6dmac_disable_chan(pd->rx_dma, pd->rx_chan);
	s6dmac_disable_error_irqs(pd->tx_dma, 1 << S6_HIFDMA_GMACTX);
	s6dmac_disable_error_irqs(pd->rx_dma, 1 << S6_HIFDMA_GMACRX);
}

static int s6gmac_tx(struct sk_buff *skb, struct net_device *dev)
{
	struct s6gmac *pd = netdev_priv(dev);
	unsigned long flags;

	spin_lock_irqsave(&pd->lock, flags);
	writel(skb->len << S6_GMAC_BURST_PREWR_LEN |
		0 << S6_GMAC_BURST_PREWR_CFE |
		1 << S6_GMAC_BURST_PREWR_PPE |
		1 << S6_GMAC_BURST_PREWR_FCS |
		((skb->len < ETH_ZLEN) ? 1 : 0) << S6_GMAC_BURST_PREWR_PAD,
		pd->reg + S6_GMAC_BURST_PREWR);
	s6dmac_put_fifo_cache(pd->tx_dma, pd->tx_chan,
		(u32)skb->data, pd->io, skb->len);
	if (s6dmac_fifo_full(pd->tx_dma, pd->tx_chan))
		netif_stop_queue(dev);
	if (((u8)(pd->tx_skb_i - pd->tx_skb_o)) >= S6_NUM_TX_SKB) {
		printk(KERN_ERR "GMAC BUG: skb tx ring overflow [%x, %x]\n",
			pd->tx_skb_o, pd->tx_skb_i);
		BUG();
	}
	pd->tx_skb[(pd->tx_skb_i++) % S6_NUM_TX_SKB] = skb;
	spin_unlock_irqrestore(&pd->lock, flags);
	return 0;
}

static void s6gmac_tx_timeout(struct net_device *dev)
{
	struct s6gmac *pd = netdev_priv(dev);
	unsigned long flags;
	spin_lock_irqsave(&pd->lock, flags);
	s6gmac_tx_interrupt(dev);
	spin_unlock_irqrestore(&pd->lock, flags);
}

static int s6gmac_open(struct net_device *dev)
{
	struct s6gmac *pd = netdev_priv(dev);
	unsigned long flags;
	phy_read_status(pd->phydev);
	spin_lock_irqsave(&pd->lock, flags);
	pd->link.mbit = 0;
	s6gmac_linkisup(dev, pd->phydev->link);
	s6gmac_init_device(dev);
	s6gmac_init_stats(dev);
	s6gmac_init_dmac(dev);
	s6gmac_rx_fillfifo(dev);
	s6dmac_enable_chan(pd->rx_dma, pd->rx_chan,
		2, 1, 0, 1, 0, 0, 0, 7, -1, 2, 0, 1);
	s6dmac_enable_chan(pd->tx_dma, pd->tx_chan,
		2, 0, 1, 0, 0, 0, 0, 7, -1, 2, 0, 1);
	writel(0 << S6_GMAC_HOST_INT_TXBURSTOVER |
		0 << S6_GMAC_HOST_INT_TXPREWOVER |
		0 << S6_GMAC_HOST_INT_RXBURSTUNDER |
		0 << S6_GMAC_HOST_INT_RXPOSTRFULL |
		0 << S6_GMAC_HOST_INT_RXPOSTRUNDER,
		pd->reg + S6_GMAC_HOST_INTMASK);
	spin_unlock_irqrestore(&pd->lock, flags);
	phy_start(pd->phydev);
	netif_start_queue(dev);
	return 0;
}

static int s6gmac_stop(struct net_device *dev)
{
	struct s6gmac *pd = netdev_priv(dev);
	unsigned long flags;
	netif_stop_queue(dev);
	phy_stop(pd->phydev);
	spin_lock_irqsave(&pd->lock, flags);
	s6gmac_init_dmac(dev);
	s6gmac_stop_device(dev);
	while (pd->tx_skb_i != pd->tx_skb_o)
		dev_kfree_skb(pd->tx_skb[(pd->tx_skb_o++) % S6_NUM_TX_SKB]);
	while (pd->rx_skb_i != pd->rx_skb_o)
		dev_kfree_skb(pd->rx_skb[(pd->rx_skb_o++) % S6_NUM_RX_SKB]);
	spin_unlock_irqrestore(&pd->lock, flags);
	return 0;
}

static struct net_device_stats *s6gmac_stats(struct net_device *dev)
{
	struct s6gmac *pd = netdev_priv(dev);
	struct net_device_stats *st = (struct net_device_stats *)&pd->stats;
	int i;
	do {
		unsigned long flags;
		spin_lock_irqsave(&pd->lock, flags);
		for (i = 0; i < ARRAY_SIZE(pd->stats); i++)
			pd->stats[i] =
				pd->carry[i] << (S6_GMAC_STAT_SIZE_MIN - 1);
		s6gmac_stats_collect(pd, &statinf[0][0]);
		s6gmac_stats_collect(pd, &statinf[1][0]);
		i = s6gmac_stats_pending(pd, 0) |
			s6gmac_stats_pending(pd, 1);
		spin_unlock_irqrestore(&pd->lock, flags);
	} while (i);
	st->rx_errors = st->rx_crc_errors +
			st->rx_frame_errors +
			st->rx_length_errors +
			st->rx_missed_errors;
	st->tx_errors += st->tx_aborted_errors;
	return st;
}

static int __devinit s6gmac_probe(struct platform_device *pdev)
{
	struct net_device *dev;
	struct s6gmac *pd;
	int res;
	unsigned long i;
	struct mii_bus *mb;

	dev = alloc_etherdev(sizeof(*pd));
	if (!dev)
		return -ENOMEM;

	dev->open = s6gmac_open;
	dev->stop = s6gmac_stop;
	dev->hard_start_xmit = s6gmac_tx;
	dev->tx_timeout = s6gmac_tx_timeout;
	dev->watchdog_timeo = HZ;
	dev->get_stats = s6gmac_stats;
	dev->irq = platform_get_irq(pdev, 0);
	pd = netdev_priv(dev);
	memset(pd, 0, sizeof(*pd));
	spin_lock_init(&pd->lock);
	pd->reg = platform_get_resource(pdev, IORESOURCE_MEM, 0)->start;
	i = platform_get_resource(pdev, IORESOURCE_DMA, 0)->start;
	pd->tx_dma = DMA_MASK_DMAC(i);
	pd->tx_chan = DMA_INDEX_CHNL(i);
	i = platform_get_resource(pdev, IORESOURCE_DMA, 1)->start;
	pd->rx_dma = DMA_MASK_DMAC(i);
	pd->rx_chan = DMA_INDEX_CHNL(i);
	pd->io = platform_get_resource(pdev, IORESOURCE_IO, 0)->start;
	res = request_irq(dev->irq, s6gmac_interrupt, 0, dev->name, dev);
	if (res) {
		printk(KERN_ERR DRV_PRMT "irq request failed: %d\n", dev->irq);
		goto errirq;
	}
	res = register_netdev(dev);
	if (res) {
		printk(KERN_ERR DRV_PRMT "error registering device %s\n",
			dev->name);
		goto errdev;
	}
	mb = mdiobus_alloc();
	if (!mb) {
		printk(KERN_ERR DRV_PRMT "error allocating mii bus\n");
		goto errmii;
	}
	mb->name = "s6gmac_mii";
	mb->read = s6mii_read;
	mb->write = s6mii_write;
	mb->reset = s6mii_reset;
	mb->priv = pd;
	snprintf(mb->id, MII_BUS_ID_SIZE, "%s-%x", pdev->name, pdev->id);
	mb->phy_mask = ~(1 << 0);
	mb->irq = &pd->mii.irq[0];
	for (i = 0; i < PHY_MAX_ADDR; i++) {
		int n = platform_get_irq(pdev, i + 1);
		if (n < 0)
			n = PHY_POLL;
		pd->mii.irq[i] = n;
	}
	mdiobus_register(mb);
	pd->mii.bus = mb;
	res = s6gmac_phy_start(dev);
	if (res)
		return res;
	platform_set_drvdata(pdev, dev);
	return 0;
errmii:
	unregister_netdev(dev);
errdev:
	free_irq(dev->irq, dev);
errirq:
	free_netdev(dev);
	return res;
}

static int __devexit s6gmac_remove(struct platform_device *pdev)
{
	struct net_device *dev = platform_get_drvdata(pdev);
	if (dev) {
		struct s6gmac *pd = netdev_priv(dev);
		mdiobus_unregister(pd->mii.bus);
		unregister_netdev(dev);
		free_irq(dev->irq, dev);
		free_netdev(dev);
		platform_set_drvdata(pdev, NULL);
	}
	return 0;
}

static struct platform_driver s6gmac_driver = {
	.probe = s6gmac_probe,
	.remove = __devexit_p(s6gmac_remove),
	.driver = {
		.name = "s6gmac",
		.owner = THIS_MODULE,
	},
};

static int __init s6gmac_init(void)
{
	printk(KERN_INFO DRV_PRMT "S6 GMAC ethernet driver\n");
	return platform_driver_register(&s6gmac_driver);
}


static void __exit s6gmac_exit(void)
{
	platform_driver_unregister(&s6gmac_driver);
}

module_init(s6gmac_init);
module_exit(s6gmac_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("S6105 on chip Ethernet driver");
MODULE_AUTHOR("Oskar Schirmer <oskar@scara.com>");