#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"

/*
 * Driver written for the 'Notebook Computer Ethernet LAN Adapter',
 * a plug-in to the bus-slot on the rear of the Gateway NOMAD 425DXL
 * laptop. The manual says NE2000 compatible.
 * The interface appears to be pretty well described in the National
 * Semiconductor Local Area Network Databook (1992) as one of the
 * AT evaluation boards.
 *
 * The NE2000 is really just a DP8390 plus a data port
 * and a reset port.
 */
enum {
	Data		= 0x10,		/* offset from I/O base of data port */
	Reset		= 0x18,		/* offset from I/O base of reset port */
};

static int
reset(Ctlr *ctlr)
{
	Board *board = ctlr->board;
	ushort buf[16];
	int i;

	/*
	 * We look for boards.
	 * We look for boards to make us barf.
	 */
	for(board->io = 0x300; board->io < 0x380; board->io += 0x20){
		/*
		 * Reset the board. This is done by doing a read
		 * followed by a write to the Reset address.
		 */
		outb(board->io+Reset, inb(board->io+Reset));

		/*
		 * Init the (possible) chip, then use the (possible)
		 * chip to read the (possible) PROM for ethernet address
		 * and a marker byte.
		 * We could just look at the DP8390 command register after
		 * initialisation has been tried, but that wouldn't be
		 * enough, there are other ethernet boards which could
		 * match.
		 */
		board->dp8390 = board->io;
		board->data = board->io+Data;
		dp8390reset(ctlr);
		memset(buf, 0, sizeof(buf));
		dp8390read(ctlr, buf, 0, sizeof(buf));
		if(buf[0x0E] == 0x57 && buf[0x0F] == 0x57)
			break;
	}
	if(board->io >= 0x380)
		return -1;

	/*
	 * Stupid machine. We asked for shorts, we got shorts,
	 * although the PROM is a byte array.
	 * Now we can set the ethernet address.
	 */
	for(i = 0; i < sizeof(ctlr->ea); i++)
		ctlr->ea[i] = buf[i];
	dp8390setea(ctlr);

	print("NE2000 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");

	return 0;
}

Board ether2000 = {
	reset,
	0,			/* init */
	dp8390attach,
	dp8390mode,
	dp8390receive,
	dp8390transmit,
	dp8390intr,
	0,			/* watch */

	0x300,			/* addr */
	2,			/* irq */
	1,			/* bit16 */

	0,			/* ram */
	0x4000,			/* ramstart */
	0x4000+16*1024,		/* ramstop */

	0x300,			/* dp8390 */
	0x300+Data,		/* data */
	0x4000/Dp8390BufSz,	/* tstart */
	0x4600/Dp8390BufSz,	/* pstart */
	0x8000/Dp8390BufSz,	/* pstop */
};