linux-imx

/*

 * Driver for the SWIM3 (Super Woz Integrated Machine 3)

 * floppy controller found on Power Macintoshes.

 *

 * Copyright (C) 1996 Paul Mackerras.

 *

 * 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.

 */

​

/*

 * TODO:

 * handle 2 drives

 * handle GCR disks

 */

​

#undef DEBUG

​

#include <linux/stddef.h>

#include <linux/kernel.h>

#include <linux/sched/signal.h>

#include <linux/timer.h>

#include <linux/delay.h>

#include <linux/fd.h>

#include <linux/ioctl.h>

#include <linux/blk-mq.h>

#include <linux/interrupt.h>

#include <linux/mutex.h>

#include <linux/module.h>

#include <linux/spinlock.h>

#include <linux/wait.h>

#include <asm/io.h>

#include <asm/dbdma.h>

#include <asm/prom.h>

#include <linux/uaccess.h>

#include <asm/mediabay.h>

#include <asm/machdep.h>

#include <asm/pmac_feature.h>

​

#define MAX_FLOPPIES    2

​

static DEFINE_MUTEX(swim3_mutex);

static struct gendisk *disks[MAX_FLOPPIES];

​

enum swim_state {

    idle,

    locating,

    seeking,

    settling,

    do_transfer,

    jogging,

    available,

    revalidating,

    ejecting

};

​

#define REG(x)  unsigned char x; char x ## _pad[15];

​

/*

 * The names for these registers mostly represent speculation on my part.

 * It will be interesting to see how close they are to the names Apple uses.

 */

struct swim3 {

    REG(data);

    REG(timer);     /* counts down at 1MHz */

    REG(error);

    REG(mode);

    REG(select);        /* controls CA0, CA1, CA2 and LSTRB signals */

    REG(setup);

    REG(control);       /* writing bits clears them */

    REG(status);        /* writing bits sets them in control */

    REG(intr);

    REG(nseek);     /* # tracks to seek */

    REG(ctrack);        /* current track number */

    REG(csect);     /* current sector number */

    REG(gap3);      /* size of gap 3 in track format */

    REG(sector);        /* sector # to read or write */

    REG(nsect);     /* # sectors to read or write */

    REG(intr_enable);

};

​

#define control_bic control

#define control_bis status

​

/* Bits in select register */

#define CA_MASK     7

#define LSTRB       8

​

/* Bits in control register */

#define DO_SEEK     0x80