ether2114x.c

这是一个同样来自贝尔实验室的和UNIX有着渊源的操作系统, 其简洁的设计和实现易于我们学习和理解

/*
 * Digital Semiconductor DECchip 2114x PCI Fast Ethernet LAN Controller.
 * To do:
 *	thresholds;
 *	ring sizing;
 *	handle more error conditions;
 *	tidy setup packet mess;
 *	push initialisation back to attach;
 *	full SROM decoding.
 */
#include "all.h"
#include "io.h"
#include "mem.h"

#include "../ip/ip.h"
#include "etherif.h"

#define DEBUG		(0)
#define debug		if(DEBUG)print

enum {
	Nrde		= 64,
	Ntde		= 64,
};

#define Rbsz		ROUNDUP(sizeof(Enpkt)+4, 4)

enum {					/* CRS0 - Bus Mode */
	Swr		= 0x00000001,	/* Software Reset */
	Bar		= 0x00000002,	/* Bus Arbitration */
	Dsl		= 0x0000007C,	/* Descriptor Skip Length (field) */
	Ble		= 0x00000080,	/* Big/Little Endian */
	Pbl		= 0x00003F00,	/* Programmable Burst Length (field) */
	Cal		= 0x0000C000,	/* Cache Alignment (field) */
	Cal8		= 0x00004000,	/* 8 longword boundary alignment */
	Cal16		= 0x00008000,	/* 16 longword boundary alignment */
	Cal32		= 0x0000C000,	/* 32 longword boundary alignment */
	Tap		= 0x000E0000,	/* Transmit Automatic Polling (field) */
	Dbo		= 0x00100000,	/* Descriptor Byte Ordering Mode */
	Rml		= 0x00200000,	/* Read Multiple */
}; 

enum {					/* CSR[57] - Status and Interrupt Enable */
	Ti		= 0x00000001,	/* Transmit Interrupt */
	Tps		= 0x00000002,	/* Transmit Process Stopped */
	Tu		= 0x00000004,	/* Transmit buffer Unavailable */
	Tjt		= 0x00000008,	/* Transmit Jabber Timeout */
	Unf		= 0x00000020,	/* transmit UNderFlow */
	Ri		= 0x00000040,	/* Receive Interrupt */
	Ru		= 0x00000080,	/* Receive buffer Unavailable */
	Rps		= 0x00000100,	/* Receive Process Stopped */
	Rwt		= 0x00000200,	/* Receive Watchdog Timeout */
	Eti		= 0x00000400,	/* Early Transmit Interrupt */
	Gte		= 0x00000800,	/* General purpose Timer Expired */
	Fbe		= 0x00002000,	/* Fatal Bit Error */
	Ais		= 0x00008000,	/* Abnormal Interrupt Summary */
	Nis		= 0x00010000,	/* Normal Interrupt Summary */
	Rs		= 0x000E0000,	/* Receive process State (field) */
	Ts		= 0x00700000,	/* Transmit process State (field) */
	Eb		= 0x03800000,	/* Error bits */
};

enum {					/* CSR6 - Operating Mode */
	Hp		= 0x00000001,	/* Hash/Perfect receive filtering mode */
	Sr		= 0x00000002,	/* Start/stop Receive */
	Ho		= 0x00000004,	/* Hash-Only filtering mode */
	Pb		= 0x00000008,	/* Pass Bad frames */
	If		= 0x00000010,	/* Inverse Filtering */
	Sb		= 0x00000020,	/* Start/stop Backoff counter */
	Pr		= 0x00000040,	/* Promiscuous Mode */
	Pm		= 0x00000080,	/* Pass all Multicast */
	Fd		= 0x00000200,	/* Full Duplex mode */
	Om		= 0x00000C00,	/* Operating Mode (field) */
	Fc		= 0x00001000,	/* Force Collision */
	St		= 0x00002000,	/* Start/stop Transmission Command */
	Tr		= 0x0000C000,	/* ThReshold control bits (field) */
	Tr128		= 0x00000000,
	Tr256		= 0x00004000,
	Tr512		= 0x00008000,
	Tr1024		= 0x0000C000,
	Ca		= 0x00020000,	/* CApture effect enable */
	Ps		= 0x00040000,	/* Port Select */
	Hbd		= 0x00080000,	/* HeartBeat Disable */
	Imm		= 0x00100000,	/* IMMediate mode */
	Sf		= 0x00200000,	/* Store and Forward */
	Ttm		= 0x00400000,	/* Transmit Threshold Mode */
	Pcs		= 0x00800000,	/* PCS function */
	Scr		= 0x01000000,	/* SCRambler mode */
	Mbo		= 0x02000000,	/* Must Be One */
	Ra		= 0x40000000,	/* Receive All */
	Sc		= 0x80000000,	/* Special Capture effect enable */

	TrMODE		= Tr512,	/* default transmission threshold */
};

enum {					/* CSR9 - ROM and MII Management */
	Scs		= 0x00000001,	/* serial ROM chip select */
	Sclk		= 0x00000002,	/* serial ROM clock */
	Sdi		= 0x00000004,	/* serial ROM data in */
	Sdo		= 0x00000008,	/* serial ROM data out */
	Ss		= 0x00000800,	/* serial ROM select */
	Wr		= 0x00002000,	/* write */
	Rd		= 0x00004000,	/* read */

	Mdc		= 0x00010000,	/* MII management clock */
	Mdo		= 0x00020000,	/* MII management write data */
	Mii		= 0x00040000,	/* MII management operation mode (W) */
	Mdi		= 0x00080000,	/* MII management data in */
};

enum {					/* CSR12 - General-Purpose Port */
	Gpc		= 0x00000100,	/* General Purpose Control */
};

typedef struct Des {
	int	status;
	int	control;
	ulong	addr;
	Msgbuf*	mb;
} Des;

enum {					/* status */
	Of		= 0x00000001,	/* Rx: OverFlow */
	Ce		= 0x00000002,	/* Rx: CRC Error */
	Db		= 0x00000004,	/* Rx: Dribbling Bit */
	Re		= 0x00000008,	/* Rx: Report on MII Error */
	Rw		= 0x00000010,	/* Rx: Receive Watchdog */
	Ft		= 0x00000020,	/* Rx: Frame Type */
	Cs		= 0x00000040,	/* Rx: Collision Seen */
	Tl		= 0x00000080,	/* Rx: Frame too Long */
	Ls		= 0x00000100,	/* Rx: Last deScriptor */
	Fs		= 0x00000200,	/* Rx: First deScriptor */
	Mf		= 0x00000400,	/* Rx: Multicast Frame */
	Rf		= 0x00000800,	/* Rx: Runt Frame */
	Dt		= 0x00003000,	/* Rx: Data Type (field) */
	De		= 0x00004000,	/* Rx: Descriptor Error */
	Fl		= 0x3FFF0000,	/* Rx: Frame Length (field) */
	Ff		= 0x40000000,	/* Rx: Filtering Fail */

	Def		= 0x00000001,	/* Tx: DEFerred */
	Uf		= 0x00000002,	/* Tx: UnderFlow error */
	Lf		= 0x00000004,	/* Tx: Link Fail report */
	Cc		= 0x00000078,	/* Tx: Collision Count (field) */
	Hf		= 0x00000080,	/* Tx: Heartbeat Fail */
	Ec		= 0x00000100,	/* Tx: Excessive Collisions */
	Lc		= 0x00000200,	/* Tx: Late Collision */
	Nc		= 0x00000400,	/* Tx: No Carrier */
	Lo		= 0x00000800,	/* Tx: LOss of carrier */
	To		= 0x00004000,	/* Tx: Transmission jabber timeOut */

	Es		= 0x00008000,	/* [RT]x: Error Summary */
	Own		= 0x80000000,	/* [RT]x: OWN bit */
};

enum {					/* control */
	Bs1		= 0x000007FF,	/* [RT]x: Buffer 1 Size */
	Bs2		= 0x003FF800,	/* [RT]x: Buffer 2 Size */

	Ch		= 0x01000000,	/* [RT]x: second address CHained */
	Er		= 0x02000000,	/* [RT]x: End of Ring */

	Ft0		= 0x00400000,	/* Tx: Filtering Type 0 */
	Dpd		= 0x00800000,	/* Tx: Disabled PaDding */
	Ac		= 0x04000000,	/* Tx: Add CRC disable */
	Set		= 0x08000000,	/* Tx: SETup packet */
	Ft1		= 0x10000000,	/* Tx: Filtering Type 1 */
	Fseg		= 0x20000000,	/* Tx: First SEGment */
	Lseg		= 0x40000000,	/* Tx: Last SEGment */
	Ic		= 0x80000000,	/* Tx: Interrupt on Completion */
};

enum {					/* PHY registers */
	Bmcr		= 0,		/* Basic Mode Control */
	Bmsr		= 1,		/* Basic Mode Status */
	Phyidr1		= 2,		/* PHY Identifier #1 */
	Phyidr2		= 3,		/* PHY Identifier #2 */
	Anar		= 4,		/* Auto-Negotiation Advertisment */
	Anlpar		= 5,		/* Auto-Negotiation Link Partner Ability */
	Aner		= 6,		/* Auto-Negotiation Expansion */
};

enum {					/* Variants */
	Tulip0		= (0x0009<<16)|0x1011,
	Tulip3		= (0x0019<<16)|0x1011,
	Pnic		= (0x0002<<16)|0x11AD,
	Pnic2		= (0xC115<<16)|0x11AD,
};

typedef struct Ctlr Ctlr;
typedef struct Ctlr {
	int	port;
	Pcidev*	pcidev;
	Ctlr*	next;
	int	active;
	int	id;			/* (pcidev->did<<16)|pcidev->vid */

	uchar	srom[128];
	uchar*	sromea;			/* MAC address */
	uchar*	leaf;
	int	sct;			/* selected connection type */
	int	k;			/* info block count */
	uchar*	infoblock[16];
	int	sctk;			/* sct block index */
	int	curk;			/* current block index */
	uchar*	type5block;

	int	phy[32];		/* logical to physical map */
	int	phyreset;		/* reset bitmap */
	int	curphyad;
	int	fdx;
	int	ttm;

	uchar	fd;			/* option */
	int	medium;			/* option */

	int	csr6;			/* CSR6 - operating mode */
	int	mask;			/* CSR[57] - interrupt mask */
	int	mbps;

	Lock	lock;

	Des*	rdr;			/* receive descriptor ring */
	int	nrdr;			/* size of rdr */
	int	rdrx;			/* index into rdr */

	Lock	tlock;
	Des*	tdr;			/* transmit descriptor ring */
	int	ntdr;			/* size of tdr */
	int	tdrh;			/* host index into tdr */
	int	tdri;			/* interface index into tdr */
	int	ntq;			/* descriptors active */
	int	ntqmax;
	Msgbuf*	setupmb;

	ulong	of;			/* receive statistics */
	ulong	ce;
	ulong	cs;
	ulong	tl;
	ulong	rf;
	ulong	de;

	ulong	ru;
	ulong	rps;
	ulong	rwt;

	ulong	uf;			/* transmit statistics */
	ulong	ec;
	ulong	lc;
	ulong	nc;
	ulong	lo;
	ulong	to;

	ulong	tps;
	ulong	tu;
	ulong	tjt;
	ulong	unf;
} Ctlr;

static Ctlr* ctlrhead;
static Ctlr* ctlrtail;

#define csr32r(c, r)	(inl((c)->port+((r)*8)))
#define csr32w(c, r, l)	(outl((c)->port+((r)*8), (ulong)(l)))

static void
attach(Ether* ether)
{
	Ctlr *ctlr;

	ctlr = ether->ctlr;
	ilock(&ctlr->lock);
	if(!(ctlr->csr6 & Sr)){
		ctlr->csr6 |= Sr;
		csr32w(ctlr, 6, ctlr->csr6);
	}
	iunlock(&ctlr->lock);
}

static void
txstart(Ether* ether)
{
	Ctlr *ctlr;
	Msgbuf *mb;
	Des *des;
	int control;

	ctlr = ether->ctlr;
	while(ctlr->ntq < (ctlr->ntdr-1)){
		if(ctlr->setupmb){
			mb = ctlr->setupmb;
			ctlr->setupmb = 0;
			control = Ic|Set|mb->count;
		}
		else{
			mb = etheroq(ether);
			if(mb == nil)
				break;
			control = Ic|Lseg|Fseg|mb->count;
		}

		ctlr->tdr[PREV(ctlr->tdrh, ctlr->ntdr)].control &= ~Ic;
		des = &ctlr->tdr[ctlr->tdrh];
		des->mb = mb;
		des->addr = PADDR(mb->data);
		des->control |= control;
		ctlr->ntq++;
		coherence();
		des->status = Own;
		csr32w(ctlr, 1, 0);
		ctlr->tdrh = NEXT(ctlr->tdrh, ctlr->ntdr);
	}

	if(ctlr->ntq > ctlr->ntqmax)
		ctlr->ntqmax = ctlr->ntq;
}

static void
transmit(Ether* ether)
{
	Ctlr *ctlr;

	ctlr = ether->ctlr;
	ilock(&ctlr->tlock);
	txstart(ether);
	iunlock(&ctlr->tlock);
}

static void
interrupt(Ureg*, void* arg)
{
	Ctlr *ctlr;
	Ether *ether;
	int len, status;
	Des *des;
	Msgbuf *mb, *rmb;

	ether = arg;
	ctlr = ether->ctlr;

	while((status = csr32r(ctlr, 5)) & (Nis|Ais)){
		/*
		 * Acknowledge the interrupts and mask-out
		 * the ones that are implicitly handled.
		 */
		csr32w(ctlr, 5, status);
		status &= (ctlr->mask & ~(Nis|Ti));

		if(status & Ais){
			if(status & Tps)
				ctlr->tps++;
			if(status & Tu)
				ctlr->tu++;
			if(status & Tjt)
				ctlr->tjt++;
			if(status & Ru)
				ctlr->ru++;
			if(status & Rps)
				ctlr->rps++;
			if(status & Rwt)
				ctlr->rwt++;
			status &= ~(Ais|Rwt|Rps|Ru|Tjt|Tu|Tps);
		}

		/*
		 * Received packets.
		 */
		if(status & Ri){
			des = &ctlr->rdr[ctlr->rdrx];
			while(!(des->status & Own)){
				if(des->status & Es){
					if(des->status & Of)
						ctlr->of++;
					if(des->status & Ce)
						ctlr->ce++;
					if(des->status & Cs)
						ctlr->cs++;
					if(des->status & Tl)
						ctlr->tl++;
					if(des->status & Rf)
						ctlr->rf++;
					if(des->status & De)
						ctlr->de++;
				}
				else if(mb = mballoc(Rbsz, 0, Mbeth1)){
					rmb = des->mb;
					rmb->count = ((des->status & Fl)>>16)-4;
					etheriq(ether, rmb);
					des->mb = mb;
					des->addr = PADDR(mb->data);
				}

				des->control &= Er;
				des->control |= Rbsz;
				coherence();
				des->status = Own;

				ctlr->rdrx = NEXT(ctlr->rdrx, ctlr->nrdr);
				des = &ctlr->rdr[ctlr->rdrx];
			}
			status &= ~Ri;
		}

		/*
		 * Check the transmit side:
		 *	check for Transmit Underflow and Adjust
		 *	the threshold upwards;
		 *	free any transmitted buffers and try to
		 *	top-up the ring.
		 */
		if(status & Unf){
			ctlr->unf++;
			ilock(&ctlr->lock);
			csr32w(ctlr, 6, ctlr->csr6 & ~St);
			switch(ctlr->csr6 & Tr){
			case Tr128:
				len = Tr256;
				break;
			case Tr256:
				len = Tr512;
				break;
			case Tr512:
				len = Tr1024;
				break;
			default:
			case Tr1024:
				len = Sf;
				break;
			}
			ctlr->csr6 = (ctlr->csr6 & ~Tr)|len;
			csr32w(ctlr, 6, ctlr->csr6);
			iunlock(&ctlr->lock);
			csr32w(ctlr, 5, Tps);
			status &= ~(Unf|Tps);
		}

		ilock(&ctlr->tlock);
		while(ctlr->ntq){
			des = &ctlr->tdr[ctlr->tdri];
			if(des->status & Own)
				break;

			if(des->status & Es){
				if(des->status & Uf)
					ctlr->uf++;
				if(des->status & Ec)
					ctlr->ec++;
				if(des->status & Lc)
					ctlr->lc++;
				if(des->status & Nc)
					ctlr->nc++;
				if(des->status & Lo)
					ctlr->lo++;
				if(des->status & To)
					ctlr->to++;
			}

			mbfree(des->mb);
			des->control &= Er;

			ctlr->ntq--;
			ctlr->tdri = NEXT(ctlr->tdri, ctlr->ntdr);
		}
		txstart(ether);
		iunlock(&ctlr->tlock);

		/*
		 * Anything left not catered for?
		 */
		if(status)
			panic("#l%d: status %8.8uX\n", ether->ctlrno, status);
	}
}

static void
ctlrinit(Ether* ether)
{