#include "u.h"
#include "../port/lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "../port/error.h"
#include "io.h"
#include "devtab.h"

#include "ether.h"

enum {					/* 83C584 Bus Interface Controller */
	Msr		= 0x00,		/* Memory Select Register */
	Icr		= 0x01,		/* Interface Configuration Register */
	Iar		= 0x02,		/* I/O Address Register */
	Bio		= 0x03,		/* BIOS ROM Address Register */
	Irr		= 0x04,		/* Interrupt Request Register */
	Laar		= 0x05,		/* LA Address Register */
	Ijr		= 0x06,		/* Initialisation Jumpers */
	Gp2		= 0x07,		/* General Purpose Data Register */
	Lar		= 0x08,		/* LAN Address Registers */
	Id		= 0x0E,		/* Board ID byte */
	Cksum		= 0x0F,		/* Checksum */
};

enum {					/* Msr */
	Rst		= 0x80,		/* software reset */
	Menb		= 0x40,		/* memory enable */
};

enum {					/* Laar */
	ZeroWS16	= (1<<5),	/* zero wait states for 16-bit ops */
	L16en		= (1<<6),	/* enable 16-bit LAN operation */
	M16en		= (1<<7),	/* enable 16-bit memory access */
};

/*
 * Mapping from configuration bits to interrupt level.
 */
static int intrmap[] = {
	9, 3, 5, 7, 10, 11, 15, 4,
};

/*
 * Get configuration parameters, enable memory.
 */
static int
reset(Ctlr *ctlr)
{
	Board *board = ctlr->board;
	int i;
	uchar msr, icr, laar, irr, sum;

	/*
	 * Look for the interface. We read the LAN address ROM
	 * and validate the checksum - the sum of all 8 bytes
	 * should be 0xFF.
	 */
	for(board->io = 0x200; board->io < 0x400; board->io += 0x20){
		sum = 0;
		for(i = 0; i < sizeof(ctlr->ea); i++){
			ctlr->ea[i] = inb(board->io+Lar+i);
			sum += ctlr->ea[i];
		}
		sum += inb(board->io+Id);
		sum += inb(board->io+Cksum);
		if(sum == 0xFF)
			break;
	}
	if(board->io >= 0x400)
		return -1;

	/*
	 * Found it, reset it.
	 * Be careful to preserve the Msr address bits,
	 * they don't get reloaded from the EEPROM on reset.
	 */
	msr = inb(board->io+Msr);
	outb(board->io+Msr, Rst|msr);
	delay(1);
	outb(board->io+Msr, msr);
	delay(2);

	/*
	 * Check for old, dumb 8003E, which doesn't have an interface
	 * chip. Only the msr exists out of the 1st eight registers, reads
	 * of the others just alias the 2nd eight registers, the LAN
	 * address ROM. We can check icr, irr and laar against the ethernet
	 * address read above and if they match it's an 8003E (or an
	 * 8003EBT, 8003S, 8003SH or 8003WT, we don't care), in which
	 * case the default irq gets used.
	 */
	msr = inb(board->io+Msr);
	icr = inb(board->io+Icr);
	laar = inb(board->io+Laar);
	irr = inb(board->io+Irr);
	if(icr != ctlr->ea[1] || irr != ctlr->ea[4] || laar != ctlr->ea[5])
		board->irq = intrmap[((irr>>5) & 0x3)|(icr & 0x4)];
	else {
		msr = (((ulong)board->ramstart)>>13) & 0x3F;
		icr = laar = 0;
		board->watch = 0;
	}

	/*
	 * Set up the bus-size, RAM address and RAM size
	 * from the info in the configuration registers.
	 */
	board->bit16 = icr & 0x1;

	board->ram = 1;
	board->ramstart = KZERO|((msr & 0x3F)<<13);
	if(board->bit16)
		board->ramstart |= (laar & 0x1F)<<19;
	else
		board->ramstart |= 0x80000;

	if(icr & (1<<3))
		board->ramstop = 32*1024;
	else
		board->ramstop = 8*1024;
	if(board->bit16)
		board->ramstop <<= 1;
	board->ramstop += board->ramstart;

	/*
	 * Set the DP8390 ring addresses.
	 */
	board->dp8390 = board->io+0x10;
	board->pstart = HOWMANY(sizeof(Etherpkt), Dp8390BufSz);
	board->pstop = HOWMANY(board->ramstop-board->ramstart, Dp8390BufSz);
	board->tstart = 0;

	print("WD8003 I/O addr %lux width %d addr %lux size %d irq %d:",
		board->io, board->bit16 ? 16: 8, board->ramstart,
		board->ramstop-board->ramstart, board->irq);
	for(i = 0; i < sizeof(ctlr->ea); i++)
		print(" %2.2ux", ctlr->ea[i]);
	print("\n");

	/*
	 * Enable interface RAM, set interface width.
	 */
	outb(board->io+Msr, Menb|msr);
	if(board->bit16)
		outb(board->io+Laar, laar|L16en|M16en|ZeroWS16);

	/*
	 * Finally, init the 8390 and set the
	 * ethernet address.
	 */
	dp8390reset(ctlr);
	dp8390setea(ctlr);

	return 0;
}

static void
watch(Ctlr *ctlr)
{
	Board *board = ctlr->board;
	uchar msr;
	int s;

	s = splhi();
	msr = inb(board->io+Msr);
	/*
	 * If the board has reset itself,
	 * start again.
	 */
	if((msr & Menb) == 0){
		delay(100);

		dp8390reset(ctlr);
		etherinit();

		wakeup(&ctlr->tr);
		wakeup(&ctlr->rr);
	}
	splx(s);
}

/*
 * Defaults are set for the dumb 8003E
 * which can't be autoconfigured.
 */
Board ether8003 = {
	reset,
	0,			/* init */
	dp8390attach,
	dp8390mode,
	dp8390receive,
	dp8390transmit,
	dp8390intr,
	watch,

	0x280,			/* io */
	3,			/* irq */
	0,			/* bit16 */

	1,			/* ram */
	0xD0000,		/* ramstart */
	0xD0000+8*1024,		/* ramstop */
};