s6gmac: xtensa s6000 on-chip ethernet driver

The s6000 on-chip MAC supports 10/100/1000Mbit and is connected to an
external PHY via MII or RGMII interface.

[jw@emlix.com: don't use device->bus_id directly]
Signed-off-by: Oskar Schirmer <os@emlix.com>
Signed-off-by: Daniel Glockner <dg@emlix.com>
Acked-by: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Johannes Weiner <jw@emlix.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Zankel <chris@zankel.net>

3 files changed, 1085 insertions, 0 deletions

diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 892a9e4e275f..1dc721517e4c 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -2443,6 +2443,17 @@ config JME
 	  To compile this driver as a module, choose M here. The module
 	  will be called jme.
 
+config S6GMAC
+	tristate "S6105 GMAC ethernet support"
+	depends on XTENSA_VARIANT_S6000
+	select PHYLIB
+	help
+	  This driver supports the on chip ethernet device on the
+	  S6105 xtensa processor.
+
+	  To compile this driver as a module, choose M here. The module
+	  will be called s6gmac.
+
 endif # NETDEV_1000
 
 #
diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index d366fb2b40e9..4b58a59f211b 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -245,6 +245,7 @@ obj-$(CONFIG_XTENSA_XT2000_SONIC) += xtsonic.o
 
 obj-$(CONFIG_DNET) += dnet.o
 obj-$(CONFIG_MACB) += macb.o
+obj-$(CONFIG_S6GMAC) += s6gmac.o
 
 obj-$(CONFIG_ARM) += arm/
 obj-$(CONFIG_DEV_APPLETALK) += appletalk/
diff --git a/drivers/net/s6gmac.c b/drivers/net/s6gmac.c
new file mode 100644
index 000000000000..5345e47b35ac
--- /dev/null
+++ b/drivers/net/s6gmac.c
@@ -0,0 +1,1073 @@
+/*
+ * Ethernet driver for S6105 on chip network device
+ * (c)2008 emlix GmbH http://www.emlix.com
+ * Authors:	Oskar Schirmer <os@emlix.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 s6gmac *pd)
+{
+	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 = dev_alloc_skb(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->dev = dev;
+			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(pd);
+	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 ((!(p = pd->mii.bus->phy_map[i])) && (i < PHY_MAX_ADDR))
+		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);
+	dev->trans_start = jiffies;
+	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(pd);
+	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 < sizeof(pd->stats) / sizeof(unsigned long); 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) {
+		printk(KERN_ERR DRV_PRMT "etherdev alloc failed, aborting.\n");
+		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, "0");
+	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 <os@emlix.com>");