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path: root/drivers/net/sunqe.h
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/* sunqe.h: Definitions for the Sun QuadEthernet driver.
 *
 * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
 */

#ifndef _SUNQE_H
#define _SUNQE_H

/* QEC global registers. */
struct qe_globreg {
	volatile unsigned int ctrl;      /* Control                  */
	volatile unsigned int stat;      /* Status                   */
	volatile unsigned int psize;     /* Packet Size              */
	volatile unsigned int msize;     /* Local-mem size (64K)     */
	volatile unsigned int rsize;     /* Receive partition size   */
	volatile unsigned int tsize;     /* Transmit partition size  */
};

#define GLOB_CTRL_MMODE       0x40000000 /* MACE qec mode            */
#define GLOB_CTRL_BMODE       0x10000000 /* BigMAC qec mode          */
#define GLOB_CTRL_EPAR        0x00000020 /* Enable parity            */
#define GLOB_CTRL_ACNTRL      0x00000018 /* SBUS arbitration control */
#define GLOB_CTRL_B64         0x00000004 /* 64 byte dvma bursts      */
#define GLOB_CTRL_B32         0x00000002 /* 32 byte dvma bursts      */
#define GLOB_CTRL_B16         0x00000000 /* 16 byte dvma bursts      */
#define GLOB_CTRL_RESET       0x00000001 /* Reset the QEC            */

#define GLOB_STAT_TX          0x00000008 /* BigMAC Transmit IRQ      */
#define GLOB_STAT_RX          0x00000004 /* BigMAC Receive IRQ       */
#define GLOB_STAT_BM          0x00000002 /* BigMAC Global IRQ        */
#define GLOB_STAT_ER          0x00000001 /* BigMAC Error IRQ         */

#define GLOB_PSIZE_2048       0x00       /* 2k packet size           */
#define GLOB_PSIZE_4096       0x01       /* 4k packet size           */
#define GLOB_PSIZE_6144       0x10       /* 6k packet size           */
#define GLOB_PSIZE_8192       0x11       /* 8k packet size           */

/* In MACE mode, there are four qe channels.  Each channel has it's own
 * status bits in the QEC status register.  This macro picks out the
 * ones you want.
 */
#define GLOB_STAT_PER_QE(status, channel) (((status) >> ((channel) * 4)) & 0xf)

/* The following registers are for per-qe channel information/status. */
struct qe_creg {
	volatile unsigned int ctrl;       /* Control                   */
	volatile unsigned int stat;       /* Status                    */
	volatile unsigned int rxds;       /* RX descriptor ring ptr    */
	volatile unsigned int txds;       /* TX descriptor ring ptr    */
	volatile unsigned int rimask;     /* RX Interrupt Mask         */
	volatile unsigned int timask;     /* TX Interrupt Mask         */
	volatile unsigned int qmask;      /* QEC Error Interrupt Mask  */
	volatile unsigned int mmask;      /* MACE Error Interrupt Mask */
	volatile unsigned int rxwbufptr;  /* Local memory rx write ptr */
	volatile unsigned int rxrbufptr;  /* Local memory rx read ptr  */
	volatile unsigned int txwbufptr;  /* Local memory tx write ptr */
	volatile unsigned int txrbufptr;  /* Local memory tx read ptr  */
	volatile unsigned int ccnt;       /* Collision Counter         */
	volatile unsigned int pipg;       /* Inter-Frame Gap           */
};

#define CREG_CTRL_RXOFF       0x00000004  /* Disable this qe's receiver*/
#define CREG_CTRL_RESET       0x00000002  /* Reset this qe channel     */
#define CREG_CTRL_TWAKEUP     0x00000001  /* Transmitter Wakeup, 'go'. */

#define CREG_STAT_EDEFER      0x10000000  /* Excessive Defers          */
#define CREG_STAT_CLOSS       0x08000000  /* Carrier Loss              */
#define CREG_STAT_ERETRIES    0x04000000  /* More than 16 retries      */
#define CREG_STAT_LCOLL       0x02000000  /* Late TX Collision         */
#define CREG_STAT_FUFLOW      0x01000000  /* FIFO Underflow            */
#define CREG_STAT_JERROR      0x00800000  /* Jabber Error              */
#define CREG_STAT_BERROR      0x00400000  /* Babble Error              */
#define CREG_STAT_TXIRQ       0x00200000  /* Transmit Interrupt        */
#define CREG_STAT_CCOFLOW     0x00100000  /* TX Coll-counter Overflow  */
#define CREG_STAT_TXDERROR    0x00080000  /* TX Descriptor is bogus    */
#define CREG_STAT_TXLERR      0x00040000  /* Late Transmit Error       */
#define CREG_STAT_TXPERR      0x00020000  /* Transmit Parity Error     */
#define CREG_STAT_TXSERR      0x00010000  /* Transmit SBUS error ack   */
#define CREG_STAT_RCCOFLOW    0x00001000  /* RX Coll-counter Overflow  */
#define CREG_STAT_RUOFLOW     0x00000800  /* Runt Counter Overflow     */
#define CREG_STAT_MCOFLOW     0x00000400  /* Missed Counter Overflow   */
#define CREG_STAT_RXFOFLOW    0x00000200  /* RX FIFO Overflow          */
#define CREG_STAT_RLCOLL      0x00000100  /* RX Late Collision         */
#define CREG_STAT_FCOFLOW     0x00000080  /* Frame Counter Overflow    */
#define CREG_STAT_CECOFLOW    0x00000040  /* CRC Error-counter Overflow*/
#define CREG_STAT_RXIRQ       0x00000020  /* Receive Interrupt         */
#define CREG_STAT_RXDROP      0x00000010  /* Dropped a RX'd packet     */
#define CREG_STAT_RXSMALL     0x00000008  /* Receive buffer too small  */
#define CREG_STAT_RXLERR      0x00000004  /* Receive Late Error        */
#define CREG_STAT_RXPERR      0x00000002  /* Receive Parity Error      */
#define CREG_STAT_RXSERR      0x00000001  /* Receive SBUS Error ACK    */

#define CREG_STAT_ERRORS      (CREG_STAT_EDEFER|CREG_STAT_CLOSS|CREG_STAT_ERETRIES|     \
			       CREG_STAT_LCOLL|CREG_STAT_FUFLOW|CREG_STAT_JERROR|       \
			       CREG_STAT_BERROR|CREG_STAT_CCOFLOW|CREG_STAT_TXDERROR|   \
			       CREG_STAT_TXLERR|CREG_STAT_TXPERR|CREG_STAT_TXSERR|      \
			       CREG_STAT_RCCOFLOW|CREG_STAT_RUOFLOW|CREG_STAT_MCOFLOW| \
			       CREG_STAT_RXFOFLOW|CREG_STAT_RLCOLL|CREG_STAT_FCOFLOW|   \
			       CREG_STAT_CECOFLOW|CREG_STAT_RXDROP|CREG_STAT_RXSMALL|   \
			       CREG_STAT_RXLERR|CREG_STAT_RXPERR|CREG_STAT_RXSERR)

#define CREG_QMASK_COFLOW     0x00100000  /* CollCntr overflow         */
#define CREG_QMASK_TXDERROR   0x00080000  /* TXD error                 */
#define CREG_QMASK_TXLERR     0x00040000  /* TX late error             */
#define CREG_QMASK_TXPERR     0x00020000  /* TX parity error           */
#define CREG_QMASK_TXSERR     0x00010000  /* TX sbus error ack         */
#define CREG_QMASK_RXDROP     0x00000010  /* RX drop                   */
#define CREG_QMASK_RXBERROR   0x00000008  /* RX buffer error           */
#define CREG_QMASK_RXLEERR    0x00000004  /* RX late error             */
#define CREG_QMASK_RXPERR     0x00000002  /* RX parity error           */
#define CREG_QMASK_RXSERR     0x00000001  /* RX sbus error ack         */

#define CREG_MMASK_EDEFER     0x10000000  /* Excess defer              */
#define CREG_MMASK_CLOSS      0x08000000  /* Carrier loss              */
#define CREG_MMASK_ERETRY     0x04000000  /* Excess retry              */
#define CREG_MMASK_LCOLL      0x02000000  /* Late collision error      */
#define CREG_MMASK_UFLOW      0x01000000  /* Underflow                 */
#define CREG_MMASK_JABBER     0x00800000  /* Jabber error              */
#define CREG_MMASK_BABBLE     0x00400000  /* Babble error              */
#define CREG_MMASK_OFLOW      0x00000800  /* Overflow                  */
#define CREG_MMASK_RXCOLL     0x00000400  /* RX Coll-Cntr overflow     */
#define CREG_MMASK_RPKT       0x00000200  /* Runt pkt overflow         */
#define CREG_MMASK_MPKT       0x00000100  /* Missed pkt overflow       */

#define CREG_PIPG_TENAB       0x00000020  /* Enable Throttle           */
#define CREG_PIPG_MMODE       0x00000010  /* Manual Mode               */
#define CREG_PIPG_WMASK       0x0000000f  /* SBUS Wait Mask            */

/* Per-channel AMD 79C940 MACE registers. */
struct qe_mregs {
	volatile unsigned char rxfifo;   /* Receive FIFO                   */
	volatile unsigned char txfifo;   /* Transmit FIFO                  */
	volatile unsigned char txfcntl;  /* Transmit Frame Control         */
	volatile unsigned char txfstat;  /* Transmit Frame Status          */
	volatile unsigned char txrcnt;   /* Transmit Retry Count           */
	volatile unsigned char rxfcntl;  /* Receive Frame Control          */
	volatile unsigned char rxfstat;  /* Receive Frame Status           */
	volatile unsigned char ffcnt;    /* FIFO Frame Count               */
	volatile unsigned char ireg;     /* Interrupt Register             */
	volatile unsigned char imask;    /* Interrupt Mask                 */
	volatile unsigned char poll;     /* POLL Register                  */
	volatile unsigned char bconfig;  /* BIU Config                     */
	volatile unsigned char fconfig;  /* FIFO Config                    */
	volatile unsigned char mconfig;  /* MAC Config                     */
	volatile unsigned char plsconfig;/* PLS Config                     */
	volatile unsigned char phyconfig;/* PHY Config                     */
	volatile unsigned char chipid1;  /* Chip-ID, low bits              */
	volatile unsigned char chipid2;  /* Chip-ID, high bits             */
	volatile unsigned char iaconfig; /* Internal Address Config        */
	volatile unsigned char _unused0; /* Reserved...                    */
	volatile unsigned char filter;   /* Logical Address Filter         */
	volatile unsigned char ethaddr;  /* Our Ethernet Address           */
	volatile unsigned char _unused1; /* Reserved...                    */
	volatile unsigned char _unused2; /* Reserved...                    */
	volatile unsigned char mpcnt;    /* Missed Packet Count            */
	volatile unsigned char _unused3; /* Reserved...                    */
	volatile unsigned char rpcnt;    /* Runt Packet Count              */
	volatile unsigned char rccnt;    /* RX Collision Count             */
	volatile unsigned char _unused4; /* Reserved...                    */
	volatile unsigned char utest;    /* User Test                      */
	volatile unsigned char rtest1;   /* Reserved Test 1                */
	volatile unsigned char rtest2;   /* Reserved Test 2                */
};

#define MREGS_TXFCNTL_DRETRY        0x80 /* Retry disable                  */
#define MREGS_TXFCNTL_DFCS          0x08 /* Disable TX FCS                 */
#define MREGS_TXFCNTL_AUTOPAD       0x01 /* TX auto pad                    */

#define MREGS_TXFSTAT_VALID         0x80 /* TX valid                       */
#define MREGS_TXFSTAT_UNDERFLOW     0x40 /* TX underflow                   */
#define MREGS_TXFSTAT_LCOLL         0x20 /* TX late collision              */
#define MREGS_TXFSTAT_MRETRY        0x10 /* TX > 1 retries                 */
#define MREGS_TXFSTAT_ORETRY        0x08 /* TX 1 retry                     */
#define MREGS_TXFSTAT_PDEFER        0x04 /* TX pkt deferred                */
#define MREGS_TXFSTAT_CLOSS         0x02 /* TX carrier lost                */
#define MREGS_TXFSTAT_RERROR        0x01 /* TX retry error                 */

#define MREGS_TXRCNT_EDEFER         0x80 /* TX Excess defers               */
#define MREGS_TXRCNT_CMASK          0x0f /* TX retry count                 */

#define MREGS_RXFCNTL_LOWLAT        0x08 /* RX low latency                 */
#define MREGS_RXFCNTL_AREJECT       0x04 /* RX addr match rej              */
#define MREGS_RXFCNTL_AUTOSTRIP     0x01 /* RX auto strip                  */

#define MREGS_RXFSTAT_OVERFLOW      0x80 /* RX overflow                    */
#define MREGS_RXFSTAT_LCOLL         0x40 /* RX late collision              */
#define MREGS_RXFSTAT_FERROR        0x20 /* RX framing error               */
#define MREGS_RXFSTAT_FCSERROR      0x10 /* RX FCS error                   */
#define MREGS_RXFSTAT_RBCNT         0x0f /* RX msg byte count              */

#define MREGS_FFCNT_RX              0xf0 /* RX FIFO frame cnt              */
#define MREGS_FFCNT_TX              0x0f /* TX FIFO frame cnt              */

#define MREGS_IREG_JABBER           0x80 /* IRQ Jabber error               */
#define MREGS_IREG_BABBLE           0x40 /* IRQ Babble error               */
#define MREGS_IREG_COLL             0x20 /* IRQ Collision error            */
#define MREGS_IREG_RCCO             0x10 /* IRQ Collision cnt overflow     */
#define MREGS_IREG_RPKTCO           0x08 /* IRQ Runt packet count overflow */
#define MREGS_IREG_MPKTCO           0x04 /* IRQ missed packet cnt overflow */
#define MREGS_IREG_RXIRQ            0x02 /* IRQ RX'd a packet              */
#define MREGS_IREG_TXIRQ            0x01 /* IRQ TX'd a packet              */

#define MREGS_IMASK_BABBLE          0x40 /* IMASK Babble errors            */
#define MREGS_IMASK_COLL            0x20 /* IMASK Collision errors         */
#define MREGS_IMASK_MPKTCO          0x04 /* IMASK Missed pkt cnt overflow  */
#define MREGS_IMASK_RXIRQ           0x02 /* IMASK RX interrupts            */
#define MREGS_IMASK_TXIRQ           0x01 /* IMASK TX interrupts            */

#define MREGS_POLL_TXVALID          0x80 /* TX is valid                    */
#define MREGS_POLL_TDTR             0x40 /* TX data transfer request       */
#define MREGS_POLL_RDTR             0x20 /* RX data transfer request       */

#define MREGS_BCONFIG_BSWAP         0x40 /* Byte Swap                      */
#define MREGS_BCONFIG_4TS           0x00 /* 4byte transmit start point     */
#define MREGS_BCONFIG_16TS          0x10 /* 16byte transmit start point    */
#define MREGS_BCONFIG_64TS          0x20 /* 64byte transmit start point    */
#define MREGS_BCONFIG_112TS         0x30 /* 112byte transmit start point   */
#define MREGS_BCONFIG_RESET         0x01 /* SW-Reset the MACE              */

#define MREGS_FCONFIG_TXF8          0x00 /* TX fifo 8 write cycles         */
#define MREGS_FCONFIG_TXF32         0x80 /* TX fifo 32 write cycles        */
#define MREGS_FCONFIG_TXF16         0x40 /* TX fifo 16 write cycles        */
#define MREGS_FCONFIG_RXF64         0x20 /* RX fifo 64 write cycles        */
#define MREGS_FCONFIG_RXF32         0x10 /* RX fifo 32 write cycles        */
#define MREGS_FCONFIG_RXF16         0x00 /* RX fifo 16 write cycles        */
#define MREGS_FCONFIG_TFWU          0x08 /* TX fifo watermark update       */
#define MREGS_FCONFIG_RFWU          0x04 /* RX fifo watermark update       */
#define MREGS_FCONFIG_TBENAB        0x02 /* TX burst enable                */
#define MREGS_FCONFIG_RBENAB        0x01 /* RX burst enable                */

#define MREGS_MCONFIG_PROMISC       0x80 /* Promiscuous mode enable        */
#define MREGS_MCONFIG_TPDDISAB      0x40 /* TX 2part deferral enable       */
#define MREGS_MCONFIG_MBAENAB       0x20 /* Modified backoff enable        */
#define MREGS_MCONFIG_RPADISAB      0x08 /* RX physical addr disable       */
#define MREGS_MCONFIG_RBDISAB       0x04 /* RX broadcast disable           */
#define MREGS_MCONFIG_TXENAB        0x02 /* Enable transmitter             */
#define MREGS_MCONFIG_RXENAB        0x01 /* Enable receiver                */

#define MREGS_PLSCONFIG_TXMS        0x08 /* TX mode select                 */
#define MREGS_PLSCONFIG_GPSI        0x06 /* Use GPSI connector             */
#define MREGS_PLSCONFIG_DAI         0x04 /* Use DAI connector              */
#define MREGS_PLSCONFIG_TP          0x02 /* Use TwistedPair connector      */
#define MREGS_PLSCONFIG_AUI         0x00 /* Use AUI connector              */
#define MREGS_PLSCONFIG_IOENAB      0x01 /* PLS I/O enable                 */

#define MREGS_PHYCONFIG_LSTAT       0x80 /* Link status                    */
#define MREGS_PHYCONFIG_LTESTDIS    0x40 /* Disable link test logic        */
#define MREGS_PHYCONFIG_RXPOLARITY  0x20 /* RX polarity                    */
#define MREGS_PHYCONFIG_APCDISAB    0x10 /* AutoPolarityCorrect disab      */
#define MREGS_PHYCONFIG_LTENAB      0x08 /* Select low threshold           */
#define MREGS_PHYCONFIG_AUTO        0x04 /* Connector port auto-sel        */
#define MREGS_PHYCONFIG_RWU         0x02 /* Remote WakeUp                  */
#define MREGS_PHYCONFIG_AW          0x01 /* Auto Wakeup                    */

#define MREGS_IACONFIG_ACHNGE       0x80 /* Do address change              */
#define MREGS_IACONFIG_PARESET      0x04 /* Physical address reset         */
#define MREGS_IACONFIG_LARESET      0x02 /* Logical address reset          */

#define MREGS_UTEST_RTRENAB         0x80 /* Enable resv test register      */
#define MREGS_UTEST_RTRDISAB        0x40 /* Disab resv test register       */
#define MREGS_UTEST_RPACCEPT        0x20 /* Accept runt packets            */
#define MREGS_UTEST_FCOLL           0x10 /* Force collision status         */
#define MREGS_UTEST_FCSENAB         0x08 /* Enable FCS on RX               */
#define MREGS_UTEST_INTLOOPM        0x06 /* Intern lpback w/MENDEC         */
#define MREGS_UTEST_INTLOOP         0x04 /* Intern lpback                  */
#define MREGS_UTEST_EXTLOOP         0x02 /* Extern lpback                  */
#define MREGS_UTEST_NOLOOP          0x00 /* No loopback                    */

struct qe_rxd {
	unsigned int rx_flags;
	unsigned int rx_addr;
};

#define RXD_OWN      0x80000000 /* Ownership.      */
#define RXD_UPDATE   0x10000000 /* Being Updated?  */
#define RXD_LENGTH   0x000007ff /* Packet Length.  */

struct qe_txd {
	unsigned int tx_flags;
	unsigned int tx_addr;
};

#define TXD_OWN      0x80000000 /* Ownership.      */
#define TXD_SOP      0x40000000 /* Start Of Packet */
#define TXD_EOP      0x20000000 /* End Of Packet   */
#define TXD_UPDATE   0x10000000 /* Being Updated?  */
#define TXD_LENGTH   0x000007ff /* Packet Length.  */

#define TX_RING_MAXSIZE   256
#define RX_RING_MAXSIZE   256

#define TX_RING_SIZE      256
#define RX_RING_SIZE      256

#define NEXT_RX(num)       (((num) + 1) & (RX_RING_SIZE - 1))
#define NEXT_TX(num)       (((num) + 1) & (TX_RING_SIZE - 1))
#define PREV_RX(num)       (((num) - 1) & (RX_RING_SIZE - 1))
#define PREV_TX(num)       (((num) - 1) & (TX_RING_SIZE - 1))

#define TX_BUFFS_AVAIL(qp)                                    \
        (((qp)->tx_old <= (qp)->tx_new) ?                     \
	  (qp)->tx_old + (TX_RING_SIZE - 1) - (qp)->tx_new :  \
			    (qp)->tx_old - (qp)->tx_new - 1)


#define SUN4C_TX_BUFFS_AVAIL(qp)                                    \
        (((qp)->tx_old <= (qp)->tx_new) ?                           \
	  (qp)->tx_old + (SUN4C_TX_RING_SIZE - 1) - (qp)->tx_new :  \
	  (qp)->tx_old - (qp)->tx_new - (TX_RING_SIZE - SUN4C_TX_RING_SIZE))


#define RX_COPY_THRESHOLD  128
#define RX_BUF_ALLOC_SIZE  (ETH_FRAME_LEN + (64 * 3))

struct qe_init_block {
	struct qe_rxd qe_rxd[RX_RING_MAXSIZE];
	struct qe_txd qe_txd[TX_RING_MAXSIZE];
};

#define qib_offset(mem, elem) \
((__u32)((unsigned long)(&(((struct qe_init_block *)0)->mem[elem]))))

struct sunqe;

struct sunqec {
	struct qe_globreg         *gregs;             /* QEC Global Registers         */

	struct sunqe              *qes[4];
	unsigned int               qec_bursts;
	struct linux_sbus_device  *qec_sbus_dev;
	struct sunqec             *next_module;
};

#define SUN4C_PKT_BUF_SZ	1544
#define SUN4C_RX_BUFF_SIZE	SUN4C_PKT_BUF_SZ
#define SUN4C_TX_BUFF_SIZE	SUN4C_PKT_BUF_SZ

#define SUN4C_RX_RING_SIZE	16
#define SUN4C_TX_RING_SIZE	16

struct sunqe_buffers {
	char	tx_buf[SUN4C_TX_RING_SIZE][SUN4C_TX_BUFF_SIZE];
	char	pad[2];		/* Align rx_buf for copy_and_sum(). */
	char	rx_buf[SUN4C_RX_RING_SIZE][SUN4C_RX_BUFF_SIZE];
};

#define qebuf_offset(mem, elem) \
((__u32)((unsigned long)(&(((struct sunqe_buffers *)0)->mem[elem][0]))))

#define SUN4C_NEXT_RX(num)	(((num) + 1) & (SUN4C_RX_RING_SIZE - 1))
#define SUN4C_NEXT_TX(num)	(((num) + 1) & (SUN4C_TX_RING_SIZE - 1))
#define SUN4C_PREV_RX(num)	(((num) - 1) & (SUN4C_RX_RING_SIZE - 1))
#define SUN4C_PREV_TX(num)	(((num) - 1) & (SUN4C_TX_RING_SIZE - 1))

struct sunqe {
	struct qe_creg            *qcregs;           /* QEC per-channel Registers      */
	struct qe_mregs           *mregs;            /* Per-channel MACE Registers     */
	struct qe_init_block      *qe_block;         /* RX and TX descriptors          */
	__u32                      qblock_dvma;      /* RX and TX descriptors          */

	struct sk_buff            *rx_skbs[RX_RING_SIZE];
	struct sk_buff            *tx_skbs[TX_RING_SIZE];

	int                        rx_new, tx_new, rx_old, tx_old;

	struct sunqe_buffers      *sun4c_buffers; /* CPU visible address.  */
	__u32                      s4c_buf_dvma;  /* DVMA visible address. */

	struct sunqec             *parent;

	struct net_device_stats   net_stats;     /* Statistical counters               */
	struct linux_sbus_device  *qe_sbusdev;   /* QE's SBUS device struct            */
	struct device             *dev;          /* QE's netdevice struct              */
	int                        channel;      /* Who am I?                          */
};

/* We use this to acquire receive skb's that we can DMA directly into. */
#define ALIGNED_RX_SKB_ADDR(addr) \
        ((((unsigned long)(addr) + (64 - 1)) & ~(64 - 1)) - (unsigned long)(addr))

static inline struct sk_buff *qe_alloc_skb(unsigned int length, int gfp_flags)
{
	struct sk_buff *skb;

	skb = alloc_skb(length + 64, gfp_flags);
	if(skb) {
		int offset = ALIGNED_RX_SKB_ADDR(skb->data);

		if(offset)
			skb_reserve(skb, offset);
	}
	return skb;
}

#endif /* !(_SUNQE_H) */