Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1277 insertions, 0 deletions

diff --git a/drivers/block/swim3.c b/drivers/block/swim3.c
new file mode 100644
index 000000000..c2d922d12
--- /dev/null
+++ b/drivers/block/swim3.c
@@ -0,0 +1,1277 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Driver for the SWIM3 (Super Woz Integrated Machine 3)
+ * floppy controller found on Power Macintoshes.
+ *
+ * Copyright (C) 1996 Paul Mackerras.
+ */
+
+/*
+ * 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
+#define FORMAT		0x40
+#define SELECT		0x20
+#define WRITE_SECTORS	0x10
+#define DO_ACTION	0x08
+#define DRIVE2_ENABLE	0x04
+#define DRIVE_ENABLE	0x02
+#define INTR_ENABLE	0x01
+
+/* Bits in status register */
+#define FIFO_1BYTE	0x80
+#define FIFO_2BYTE	0x40
+#define ERROR		0x20
+#define DATA		0x08
+#define RDDATA		0x04
+#define INTR_PENDING	0x02
+#define MARK_BYTE	0x01
+
+/* Bits in intr and intr_enable registers */
+#define ERROR_INTR	0x20
+#define DATA_CHANGED	0x10
+#define TRANSFER_DONE	0x08
+#define SEEN_SECTOR	0x04
+#define SEEK_DONE	0x02
+#define TIMER_DONE	0x01
+
+/* Bits in error register */
+#define ERR_DATA_CRC	0x80
+#define ERR_ADDR_CRC	0x40
+#define ERR_OVERRUN	0x04
+#define ERR_UNDERRUN	0x01
+
+/* Bits in setup register */
+#define S_SW_RESET	0x80
+#define S_GCR_WRITE	0x40
+#define S_IBM_DRIVE	0x20
+#define S_TEST_MODE	0x10
+#define S_FCLK_DIV2	0x08
+#define S_GCR		0x04
+#define S_COPY_PROT	0x02
+#define S_INV_WDATA	0x01
+
+/* Select values for swim3_action */
+#define SEEK_POSITIVE	0
+#define SEEK_NEGATIVE	4
+#define STEP		1
+#define MOTOR_ON	2
+#define MOTOR_OFF	6
+#define INDEX		3
+#define EJECT		7
+#define SETMFM		9
+#define SETGCR		13
+
+/* Select values for swim3_select and swim3_readbit */
+#define STEP_DIR	0
+#define STEPPING	1
+#define MOTOR_ON	2
+#define RELAX		3	/* also eject in progress */
+#define READ_DATA_0	4
+#define ONEMEG_DRIVE	5
+#define SINGLE_SIDED	6	/* drive or diskette is 4MB type? */
+#define DRIVE_PRESENT	7
+#define DISK_IN		8
+#define WRITE_PROT	9
+#define TRACK_ZERO	10
+#define TACHO		11
+#define READ_DATA_1	12
+#define GCR_MODE	13
+#define SEEK_COMPLETE	14
+#define TWOMEG_MEDIA	15
+
+/* Definitions of values used in writing and formatting */
+#define DATA_ESCAPE	0x99
+#define GCR_SYNC_EXC	0x3f
+#define GCR_SYNC_CONV	0x80
+#define GCR_FIRST_MARK	0xd5
+#define GCR_SECOND_MARK	0xaa
+#define GCR_ADDR_MARK	"\xd5\xaa\x00"
+#define GCR_DATA_MARK	"\xd5\xaa\x0b"
+#define GCR_SLIP_BYTE	"\x27\xaa"
+#define GCR_SELF_SYNC	"\x3f\xbf\x1e\x34\x3c\x3f"
+
+#define DATA_99		"\x99\x99"
+#define MFM_ADDR_MARK	"\x99\xa1\x99\xa1\x99\xa1\x99\xfe"
+#define MFM_INDEX_MARK	"\x99\xc2\x99\xc2\x99\xc2\x99\xfc"
+#define MFM_GAP_LEN	12
+
+struct floppy_state {
+	enum swim_state	state;
+	struct swim3 __iomem *swim3;	/* hardware registers */
+	struct dbdma_regs __iomem *dma;	/* DMA controller registers */
+	int	swim3_intr;	/* interrupt number for SWIM3 */
+	int	dma_intr;	/* interrupt number for DMA channel */
+	int	cur_cyl;	/* cylinder head is on, or -1 */
+	int	cur_sector;	/* last sector we saw go past */
+	int	req_cyl;	/* the cylinder for the current r/w request */
+	int	head;		/* head number ditto */
+	int	req_sector;	/* sector number ditto */
+	int	scount;		/* # sectors we're transferring at present */
+	int	retries;
+	int	settle_time;
+	int	secpercyl;	/* disk geometry information */
+	int	secpertrack;
+	int	total_secs;
+	int	write_prot;	/* 1 if write-protected, 0 if not, -1 dunno */
+	struct dbdma_cmd *dma_cmd;
+	int	ref_count;
+	int	expect_cyl;
+	struct timer_list timeout;
+	int	timeout_pending;
+	int	ejected;
+	wait_queue_head_t wait;
+	int	wanted;
+	struct macio_dev *mdev;
+	char	dbdma_cmd_space[5 * sizeof(struct dbdma_cmd)];
+	int	index;
+	struct request *cur_req;
+	struct blk_mq_tag_set tag_set;
+};
+
+#define swim3_err(fmt, arg...)	dev_err(&fs->mdev->ofdev.dev, "[fd%d] " fmt, fs->index, arg)
+#define swim3_warn(fmt, arg...)	dev_warn(&fs->mdev->ofdev.dev, "[fd%d] " fmt, fs->index, arg)
+#define swim3_info(fmt, arg...)	dev_info(&fs->mdev->ofdev.dev, "[fd%d] " fmt, fs->index, arg)
+
+#ifdef DEBUG
+#define swim3_dbg(fmt, arg...)	dev_dbg(&fs->mdev->ofdev.dev, "[fd%d] " fmt, fs->index, arg)
+#else
+#define swim3_dbg(fmt, arg...)	do { } while(0)
+#endif
+
+static struct floppy_state floppy_states[MAX_FLOPPIES];
+static int floppy_count = 0;
+static DEFINE_SPINLOCK(swim3_lock);
+
+static unsigned short write_preamble[] = {
+	0x4e4e, 0x4e4e, 0x4e4e, 0x4e4e, 0x4e4e,	/* gap field */
+	0, 0, 0, 0, 0, 0,			/* sync field */
+	0x99a1, 0x99a1, 0x99a1, 0x99fb,		/* data address mark */
+	0x990f					/* no escape for 512 bytes */
+};
+
+static unsigned short write_postamble[] = {
+	0x9904,					/* insert CRC */
+	0x4e4e, 0x4e4e,
+	0x9908,					/* stop writing */
+	0, 0, 0, 0, 0, 0
+};
+
+static void seek_track(struct floppy_state *fs, int n);
+static void init_dma(struct dbdma_cmd *cp, int cmd, void *buf, int count);
+static void act(struct floppy_state *fs);
+static void scan_timeout(struct timer_list *t);
+static void seek_timeout(struct timer_list *t);
+static void settle_timeout(struct timer_list *t);
+static void xfer_timeout(struct timer_list *t);
+static irqreturn_t swim3_interrupt(int irq, void *dev_id);
+/*static void fd_dma_interrupt(int irq, void *dev_id);*/
+static int grab_drive(struct floppy_state *fs, enum swim_state state,
+		      int interruptible);
+static void release_drive(struct floppy_state *fs);
+static int fd_eject(struct floppy_state *fs);
+static int floppy_ioctl(struct block_device *bdev, fmode_t mode,
+			unsigned int cmd, unsigned long param);
+static int floppy_open(struct block_device *bdev, fmode_t mode);
+static void floppy_release(struct gendisk *disk, fmode_t mode);
+static unsigned int floppy_check_events(struct gendisk *disk,
+					unsigned int clearing);
+static int floppy_revalidate(struct gendisk *disk);
+
+static bool swim3_end_request(struct floppy_state *fs, blk_status_t err, unsigned int nr_bytes)
+{
+	struct request *req = fs->cur_req;
+
+	swim3_dbg("  end request, err=%d nr_bytes=%d, cur_req=%p\n",
+		  err, nr_bytes, req);
+
+	if (err)
+		nr_bytes = blk_rq_cur_bytes(req);
+	if (blk_update_request(req, err, nr_bytes))
+		return true;
+	__blk_mq_end_request(req, err);
+	fs->cur_req = NULL;
+	return false;
+}
+
+static void swim3_select(struct floppy_state *fs, int sel)
+{
+	struct swim3 __iomem *sw = fs->swim3;
+
+	out_8(&sw->select, RELAX);
+	if (sel & 8)
+		out_8(&sw->control_bis, SELECT);
+	else
+		out_8(&sw->control_bic, SELECT);
+	out_8(&sw->select, sel & CA_MASK);
+}
+
+static void swim3_action(struct floppy_state *fs, int action)
+{
+	struct swim3 __iomem *sw = fs->swim3;
+
+	swim3_select(fs, action);
+	udelay(1);
+	out_8(&sw->select, sw->select | LSTRB);
+	udelay(2);
+	out_8(&sw->select, sw->select & ~LSTRB);
+	udelay(1);
+}
+
+static int swim3_readbit(struct floppy_state *fs, int bit)
+{
+	struct swim3 __iomem *sw = fs->swim3;
+	int stat;
+
+	swim3_select(fs, bit);
+	udelay(1);
+	stat = in_8(&sw->status);
+	return (stat & DATA) == 0;
+}
+
+static blk_status_t swim3_queue_rq(struct blk_mq_hw_ctx *hctx,
+				   const struct blk_mq_queue_data *bd)
+{
+	struct floppy_state *fs = hctx->queue->queuedata;
+	struct request *req = bd->rq;
+	unsigned long x;
+
+	spin_lock_irq(&swim3_lock);
+	if (fs->cur_req || fs->state != idle) {
+		spin_unlock_irq(&swim3_lock);
+		return BLK_STS_DEV_RESOURCE;
+	}
+	blk_mq_start_request(req);
+	fs->cur_req = req;
+	if (fs->mdev->media_bay &&
+	    check_media_bay(fs->mdev->media_bay) != MB_FD) {
+		swim3_dbg("%s", "  media bay absent, dropping req\n");
+		swim3_end_request(fs, BLK_STS_IOERR, 0);
+		goto out;
+	}
+	if (fs->ejected) {
+		swim3_dbg("%s", "  disk ejected\n");
+		swim3_end_request(fs, BLK_STS_IOERR, 0);
+		goto out;
+	}
+	if (rq_data_dir(req) == WRITE) {
+		if (fs->write_prot < 0)
+			fs->write_prot = swim3_readbit(fs, WRITE_PROT);
+		if (fs->write_prot) {
+			swim3_dbg("%s", "  try to write, disk write protected\n");
+			swim3_end_request(fs, BLK_STS_IOERR, 0);
+			goto out;
+		}
+	}
+
+	/*
+	 * Do not remove the cast. blk_rq_pos(req) is now a sector_t and can be
+	 * 64 bits, but it will never go past 32 bits for this driver anyway, so
+	 * we can safely cast it down and not have to do a 64/32 division
+	 */
+	fs->req_cyl = ((long)blk_rq_pos(req)) / fs->secpercyl;
+	x = ((long)blk_rq_pos(req)) % fs->secpercyl;
+	fs->head = x / fs->secpertrack;
+	fs->req_sector = x % fs->secpertrack + 1;
+	fs->state = do_transfer;
+	fs->retries = 0;
+
+	act(fs);
+
+out:
+	spin_unlock_irq(&swim3_lock);
+	return BLK_STS_OK;
+}
+
+static void set_timeout(struct floppy_state *fs, int nticks,
+			void (*proc)(struct timer_list *t))
+{
+	if (fs->timeout_pending)
+		del_timer(&fs->timeout);
+	fs->timeout.expires = jiffies + nticks;
+	fs->timeout.function = proc;
+	add_timer(&fs->timeout);
+	fs->timeout_pending = 1;
+}
+
+static inline void scan_track(struct floppy_state *fs)
+{
+	struct swim3 __iomem *sw = fs->swim3;
+
+	swim3_select(fs, READ_DATA_0);
+	in_8(&sw->intr);		/* clear SEEN_SECTOR bit */
+	in_8(&sw->error);
+	out_8(&sw->intr_enable, SEEN_SECTOR);
+	out_8(&sw->control_bis, DO_ACTION);
+	/* enable intr when track found */
+	set_timeout(fs, HZ, scan_timeout);	/* enable timeout */
+}
+
+static inline void seek_track(struct floppy_state *fs, int n)
+{
+	struct swim3 __iomem *sw = fs->swim3;
+
+	if (n >= 0) {
+		swim3_action(fs, SEEK_POSITIVE);
+		sw->nseek = n;
+	} else {
+		swim3_action(fs, SEEK_NEGATIVE);
+		sw->nseek = -n;
+	}
+	fs->expect_cyl = (fs->cur_cyl >= 0)? fs->cur_cyl + n: -1;
+	swim3_select(fs, STEP);
+	in_8(&sw->error);
+	/* enable intr when seek finished */
+	out_8(&sw->intr_enable, SEEK_DONE);
+	out_8(&sw->control_bis, DO_SEEK);
+	set_timeout(fs, 3*HZ, seek_timeout);	/* enable timeout */
+	fs->settle_time = 0;
+}
+
+static inline void init_dma(struct dbdma_cmd *cp, int cmd,
+			    void *buf, int count)
+{
+	cp->req_count = cpu_to_le16(count);
+	cp->command = cpu_to_le16(cmd);
+	cp->phy_addr = cpu_to_le32(virt_to_bus(buf));
+	cp->xfer_status = 0;
+}
+
+static inline void setup_transfer(struct floppy_state *fs)
+{
+	int n;
+	struct swim3 __iomem *sw = fs->swim3;
+	struct dbdma_cmd *cp = fs->dma_cmd;
+	struct dbdma_regs __iomem *dr = fs->dma;
+	struct request *req = fs->cur_req;
+
+	if (blk_rq_cur_sectors(req) <= 0) {
+		swim3_warn("%s", "Transfer 0 sectors ?\n");
+		return;
+	}
+	if (rq_data_dir(req) == WRITE)
+		n = 1;
+	else {
+		n = fs->secpertrack - fs->req_sector + 1;
+		if (n > blk_rq_cur_sectors(req))
+			n = blk_rq_cur_sectors(req);
+	}
+
+	swim3_dbg("  setup xfer at sect %d (of %d) head %d for %d\n",
+		  fs->req_sector, fs->secpertrack, fs->head, n);
+
+	fs->scount = n;
+	swim3_select(fs, fs->head? READ_DATA_1: READ_DATA_0);
+	out_8(&sw->sector, fs->req_sector);
+	out_8(&sw->nsect, n);
+	out_8(&sw->gap3, 0);
+	out_le32(&dr->cmdptr, virt_to_bus(cp));
+	if (rq_data_dir(req) == WRITE) {
+		/* Set up 3 dma commands: write preamble, data, postamble */
+		init_dma(cp, OUTPUT_MORE, write_preamble, sizeof(write_preamble));
+		++cp;
+		init_dma(cp, OUTPUT_MORE, bio_data(req->bio), 512);
+		++cp;
+		init_dma(cp, OUTPUT_LAST, write_postamble, sizeof(write_postamble));
+	} else {
+		init_dma(cp, INPUT_LAST, bio_data(req->bio), n * 512);
+	}
+	++cp;
+	out_le16(&cp->command, DBDMA_STOP);
+	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
+	in_8(&sw->error);
+	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
+	if (rq_data_dir(req) == WRITE)
+		out_8(&sw->control_bis, WRITE_SECTORS);
+	in_8(&sw->intr);
+	out_le32(&dr->control, (RUN << 16) | RUN);
+	/* enable intr when transfer complete */
+	out_8(&sw->intr_enable, TRANSFER_DONE);
+	out_8(&sw->control_bis, DO_ACTION);
+	set_timeout(fs, 2*HZ, xfer_timeout);	/* enable timeout */
+}
+
+static void act(struct floppy_state *fs)
+{
+	for (;;) {
+		swim3_dbg("  act loop, state=%d, req_cyl=%d, cur_cyl=%d\n",
+			  fs->state, fs->req_cyl, fs->cur_cyl);
+
+		switch (fs->state) {
+		case idle:
+			return;		/* XXX shouldn't get here */
+
+		case locating:
+			if (swim3_readbit(fs, TRACK_ZERO)) {
+				swim3_dbg("%s", "    locate track 0\n");
+				fs->cur_cyl = 0;
+				if (fs->req_cyl == 0)
+					fs->state = do_transfer;
+				else
+					fs->state = seeking;
+				break;
+			}
+			scan_track(fs);
+			return;
+
+		case seeking:
+			if (fs->cur_cyl < 0) {
+				fs->expect_cyl = -1;
+				fs->state = locating;
+				break;
+			}
+			if (fs->req_cyl == fs->cur_cyl) {
+				swim3_warn("%s", "Whoops, seeking 0\n");
+				fs->state = do_transfer;
+				break;
+			}
+			seek_track(fs, fs->req_cyl - fs->cur_cyl);
+			return;
+
+		case settling:
+			/* check for SEEK_COMPLETE after 30ms */
+			fs->settle_time = (HZ + 32) / 33;
+			set_timeout(fs, fs->settle_time, settle_timeout);
+			return;
+
+		case do_transfer:
+			if (fs->cur_cyl != fs->req_cyl) {
+				if (fs->retries > 5) {
+					swim3_err("Wrong cylinder in transfer, want: %d got %d\n",
+						  fs->req_cyl, fs->cur_cyl);
+					swim3_end_request(fs, BLK_STS_IOERR, 0);
+					fs->state = idle;
+					return;
+				}
+				fs->state = seeking;
+				break;
+			}
+			setup_transfer(fs);
+			return;
+
+		case jogging:
+			seek_track(fs, -5);
+			return;
+
+		default:
+			swim3_err("Unknown state %d\n", fs->state);
+			return;
+		}
+	}
+}
+
+static void scan_timeout(struct timer_list *t)
+{
+	struct floppy_state *fs = from_timer(fs, t, timeout);
+	struct swim3 __iomem *sw = fs->swim3;
+	unsigned long flags;
+
+	swim3_dbg("* scan timeout, state=%d\n", fs->state);
+
+	spin_lock_irqsave(&swim3_lock, flags);
+	fs->timeout_pending = 0;
+	out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
+	out_8(&sw->select, RELAX);
+	out_8(&sw->intr_enable, 0);
+	fs->cur_cyl = -1;
+	if (fs->retries > 5) {
+		swim3_end_request(fs, BLK_STS_IOERR, 0);
+		fs->state = idle;
+	} else {
+		fs->state = jogging;
+		act(fs);
+	}
+	spin_unlock_irqrestore(&swim3_lock, flags);
+}
+
+static void seek_timeout(struct timer_list *t)
+{
+	struct floppy_state *fs = from_timer(fs, t, timeout);
+	struct swim3 __iomem *sw = fs->swim3;
+	unsigned long flags;
+
+	swim3_dbg("* seek timeout, state=%d\n", fs->state);
+
+	spin_lock_irqsave(&swim3_lock, flags);
+	fs->timeout_pending = 0;
+	out_8(&sw->control_bic, DO_SEEK);
+	out_8(&sw->select, RELAX);
+	out_8(&sw->intr_enable, 0);
+	swim3_err("%s", "Seek timeout\n");
+	swim3_end_request(fs, BLK_STS_IOERR, 0);
+	fs->state = idle;
+	spin_unlock_irqrestore(&swim3_lock, flags);
+}
+
+static void settle_timeout(struct timer_list *t)
+{
+	struct floppy_state *fs = from_timer(fs, t, timeout);
+	struct swim3 __iomem *sw = fs->swim3;
+	unsigned long flags;
+
+	swim3_dbg("* settle timeout, state=%d\n", fs->state);
+
+	spin_lock_irqsave(&swim3_lock, flags);
+	fs->timeout_pending = 0;
+	if (swim3_readbit(fs, SEEK_COMPLETE)) {
+		out_8(&sw->select, RELAX);
+		fs->state = locating;
+		act(fs);
+		goto unlock;
+	}
+	out_8(&sw->select, RELAX);
+	if (fs->settle_time < 2*HZ) {
+		++fs->settle_time;
+		set_timeout(fs, 1, settle_timeout);
+		goto unlock;
+	}
+	swim3_err("%s", "Seek settle timeout\n");
+	swim3_end_request(fs, BLK_STS_IOERR, 0);
+	fs->state = idle;
+ unlock:
+	spin_unlock_irqrestore(&swim3_lock, flags);
+}
+
+static void xfer_timeout(struct timer_list *t)
+{
+	struct floppy_state *fs = from_timer(fs, t, timeout);
+	struct swim3 __iomem *sw = fs->swim3;
+	struct dbdma_regs __iomem *dr = fs->dma;
+	unsigned long flags;
+	int n;
+
+	swim3_dbg("* xfer timeout, state=%d\n", fs->state);
+
+	spin_lock_irqsave(&swim3_lock, flags);
+	fs->timeout_pending = 0;
+	out_le32(&dr->control, RUN << 16);
+	/* We must wait a bit for dbdma to stop */
+	for (n = 0; (in_le32(&dr->status) & ACTIVE) && n < 1000; n++)
+		udelay(1);
+	out_8(&sw->intr_enable, 0);
+	out_8(&sw->control_bic, WRITE_SECTORS | DO_ACTION);
+	out_8(&sw->select, RELAX);
+	swim3_err("Timeout %sing sector %ld\n",
+	       (rq_data_dir(fs->cur_req)==WRITE? "writ": "read"),
+	       (long)blk_rq_pos(fs->cur_req));
+	swim3_end_request(fs, BLK_STS_IOERR, 0);
+	fs->state = idle;
+	spin_unlock_irqrestore(&swim3_lock, flags);
+}
+
+static irqreturn_t swim3_interrupt(int irq, void *dev_id)
+{
+	struct floppy_state *fs = (struct floppy_state *) dev_id;
+	struct swim3 __iomem *sw = fs->swim3;
+	int intr, err, n;
+	int stat, resid;
+	struct dbdma_regs __iomem *dr;
+	struct dbdma_cmd *cp;
+	unsigned long flags;
+	struct request *req = fs->cur_req;
+
+	swim3_dbg("* interrupt, state=%d\n", fs->state);
+
+	spin_lock_irqsave(&swim3_lock, flags);
+	intr = in_8(&sw->intr);
+	err = (intr & ERROR_INTR)? in_8(&sw->error): 0;
+	if ((intr & ERROR_INTR) && fs->state != do_transfer)
+		swim3_err("Non-transfer error interrupt: state=%d, dir=%x, intr=%x, err=%x\n",
+			  fs->state, rq_data_dir(req), intr, err);
+	switch (fs->state) {
+	case locating:
+		if (intr & SEEN_SECTOR) {
+			out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
+			out_8(&sw->select, RELAX);
+			out_8(&sw->intr_enable, 0);
+			del_timer(&fs->timeout);
+			fs->timeout_pending = 0;
+			if (sw->ctrack == 0xff) {
+				swim3_err("%s", "Seen sector but cyl=ff?\n");
+				fs->cur_cyl = -1;
+				if (fs->retries > 5) {
+					swim3_end_request(fs, BLK_STS_IOERR, 0);
+					fs->state = idle;
+				} else {
+					fs->state = jogging;
+					act(fs);
+				}
+				break;
+			}
+			fs->cur_cyl = sw->ctrack;
+			fs->cur_sector = sw->csect;
+			if (fs->expect_cyl != -1 && fs->expect_cyl != fs->cur_cyl)
+				swim3_err("Expected cyl %d, got %d\n",
+					  fs->expect_cyl, fs->cur_cyl);
+			fs->state = do_transfer;
+			act(fs);
+		}
+		break;
+	case seeking:
+	case jogging:
+		if (sw->nseek == 0) {
+			out_8(&sw->control_bic, DO_SEEK);
+			out_8(&sw->select, RELAX);
+			out_8(&sw->intr_enable, 0);
+			del_timer(&fs->timeout);
+			fs->timeout_pending = 0;
+			if (fs->state == seeking)
+				++fs->retries;
+			fs->state = settling;
+			act(fs);
+		}
+		break;
+	case settling:
+		out_8(&sw->intr_enable, 0);
+		del_timer(&fs->timeout);
+		fs->timeout_pending = 0;
+		act(fs);
+		break;
+	case do_transfer:
+		if ((intr & (ERROR_INTR | TRANSFER_DONE)) == 0)
+			break;
+		out_8(&sw->intr_enable, 0);
+		out_8(&sw->control_bic, WRITE_SECTORS | DO_ACTION);
+		out_8(&sw->select, RELAX);
+		del_timer(&fs->timeout);
+		fs->timeout_pending = 0;
+		dr = fs->dma;
+		cp = fs->dma_cmd;
+		if (rq_data_dir(req) == WRITE)
+			++cp;
+		/*
+		 * Check that the main data transfer has finished.
+		 * On writing, the swim3 sometimes doesn't use
+		 * up all the bytes of the postamble, so we can still
+		 * see DMA active here.  That doesn't matter as long
+		 * as all the sector data has been transferred.
+		 */
+		if ((intr & ERROR_INTR) == 0 && cp->xfer_status == 0) {
+			/* wait a little while for DMA to complete */
+			for (n = 0; n < 100; ++n) {
+				if (cp->xfer_status != 0)
+					break;
+				udelay(1);
+				barrier();
+			}
+		}
+		/* turn off DMA */
+		out_le32(&dr->control, (RUN | PAUSE) << 16);
+		stat = le16_to_cpu(cp->xfer_status);
+		resid = le16_to_cpu(cp->res_count);
+		if (intr & ERROR_INTR) {
+			n = fs->scount - 1 - resid / 512;
+			if (n > 0) {
+				blk_update_request(req, 0, n << 9);
+				fs->req_sector += n;
+			}
+			if (fs->retries < 5) {
+				++fs->retries;
+				act(fs);
+			} else {
+				swim3_err("Error %sing block %ld (err=%x)\n",
+				       rq_data_dir(req) == WRITE? "writ": "read",
+				       (long)blk_rq_pos(req), err);
+				swim3_end_request(fs, BLK_STS_IOERR, 0);
+				fs->state = idle;
+			}
+		} else {
+			if ((stat & ACTIVE) == 0 || resid != 0) {
+				/* musta been an error */
+				swim3_err("fd dma error: stat=%x resid=%d\n", stat, resid);
+				swim3_err("  state=%d, dir=%x, intr=%x, err=%x\n",
+					  fs->state, rq_data_dir(req), intr, err);
+				swim3_end_request(fs, BLK_STS_IOERR, 0);
+				fs->state = idle;
+				break;
+			}
+			fs->retries = 0;
+			if (swim3_end_request(fs, 0, fs->scount << 9)) {
+				fs->req_sector += fs->scount;
+				if (fs->req_sector > fs->secpertrack) {
+					fs->req_sector -= fs->secpertrack;
+					if (++fs->head > 1) {
+						fs->head = 0;
+						++fs->req_cyl;
+					}
+				}
+				act(fs);
+			} else
+				fs->state = idle;
+		}
+		break;
+	default:
+		swim3_err("Don't know what to do in state %d\n", fs->state);
+	}
+	spin_unlock_irqrestore(&swim3_lock, flags);
+	return IRQ_HANDLED;
+}
+
+/*
+static void fd_dma_interrupt(int irq, void *dev_id)
+{
+}
+*/
+
+/* Called under the mutex to grab exclusive access to a drive */
+static int grab_drive(struct floppy_state *fs, enum swim_state state,
+		      int interruptible)
+{
+	unsigned long flags;
+
+	swim3_dbg("%s", "-> grab drive\n");
+
+	spin_lock_irqsave(&swim3_lock, flags);
+	if (fs->state != idle && fs->state != available) {
+		++fs->wanted;
+		/* this will enable irqs in order to sleep */
+		if (!interruptible)
+			wait_event_lock_irq(fs->wait,
+                                        fs->state == available,
+                                        swim3_lock);
+		else if (wait_event_interruptible_lock_irq(fs->wait,
+					fs->state == available,
+					swim3_lock)) {
+			--fs->wanted;
+			spin_unlock_irqrestore(&swim3_lock, flags);
+			return -EINTR;
+		}
+		--fs->wanted;
+	}
+	fs->state = state;
+	spin_unlock_irqrestore(&swim3_lock, flags);
+
+	return 0;
+}
+
+static void release_drive(struct floppy_state *fs)
+{
+	struct request_queue *q = disks[fs->index]->queue;
+	unsigned long flags;
+
+	swim3_dbg("%s", "-> release drive\n");
+
+	spin_lock_irqsave(&swim3_lock, flags);
+	fs->state = idle;
+	spin_unlock_irqrestore(&swim3_lock, flags);
+
+	blk_mq_freeze_queue(q);
+	blk_mq_quiesce_queue(q);
+	blk_mq_unquiesce_queue(q);
+	blk_mq_unfreeze_queue(q);
+}
+
+static int fd_eject(struct floppy_state *fs)
+{
+	int err, n;
+
+	err = grab_drive(fs, ejecting, 1);
+	if (err)
+		return err;
+	swim3_action(fs, EJECT);
+	for (n = 20; n > 0; --n) {
+		if (signal_pending(current)) {
+			err = -EINTR;
+			break;
+		}
+		swim3_select(fs, RELAX);
+		schedule_timeout_interruptible(1);
+		if (swim3_readbit(fs, DISK_IN) == 0)
+			break;
+	}
+	swim3_select(fs, RELAX);
+	udelay(150);
+	fs->ejected = 1;
+	release_drive(fs);
+	return err;
+}
+
+static struct floppy_struct floppy_type =
+	{ 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,NULL };	/*  7 1.44MB 3.5"   */
+
+static int floppy_locked_ioctl(struct block_device *bdev, fmode_t mode,
+			unsigned int cmd, unsigned long param)
+{
+	struct floppy_state *fs = bdev->bd_disk->private_data;
+	int err;
+		
+	if ((cmd & 0x80) && !capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	if (fs->mdev->media_bay &&
+	    check_media_bay(fs->mdev->media_bay) != MB_FD)
+		return -ENXIO;
+
+	switch (cmd) {
+	case FDEJECT:
+		if (fs->ref_count != 1)
+			return -EBUSY;
+		err = fd_eject(fs);
+		return err;
+	case FDGETPRM:
+	        if (copy_to_user((void __user *) param, &floppy_type,
+				 sizeof(struct floppy_struct)))
+			return -EFAULT;
+		return 0;
+	}
+	return -ENOTTY;
+}
+
+static int floppy_ioctl(struct block_device *bdev, fmode_t mode,
+				 unsigned int cmd, unsigned long param)
+{
+	int ret;
+
+	mutex_lock(&swim3_mutex);
+	ret = floppy_locked_ioctl(bdev, mode, cmd, param);
+	mutex_unlock(&swim3_mutex);
+
+	return ret;
+}
+
+static int floppy_open(struct block_device *bdev, fmode_t mode)
+{
+	struct floppy_state *fs = bdev->bd_disk->private_data;
+	struct swim3 __iomem *sw = fs->swim3;
+	int n, err = 0;
+
+	if (fs->ref_count == 0) {
+		if (fs->mdev->media_bay &&
+		    check_media_bay(fs->mdev->media_bay) != MB_FD)
+			return -ENXIO;
+		out_8(&sw->setup, S_IBM_DRIVE | S_FCLK_DIV2);
+		out_8(&sw->control_bic, 0xff);
+		out_8(&sw->mode, 0x95);
+		udelay(10);
+		out_8(&sw->intr_enable, 0);
+		out_8(&sw->control_bis, DRIVE_ENABLE | INTR_ENABLE);
+		swim3_action(fs, MOTOR_ON);
+		fs->write_prot = -1;
+		fs->cur_cyl = -1;
+		for (n = 0; n < 2 * HZ; ++n) {
+			if (n >= HZ/30 && swim3_readbit(fs, SEEK_COMPLETE))
+				break;
+			if (signal_pending(current)) {
+				err = -EINTR;
+				break;
+			}
+			swim3_select(fs, RELAX);
+			schedule_timeout_interruptible(1);
+		}
+		if (err == 0 && (swim3_readbit(fs, SEEK_COMPLETE) == 0
+				 || swim3_readbit(fs, DISK_IN) == 0))
+			err = -ENXIO;
+		swim3_action(fs, SETMFM);
+		swim3_select(fs, RELAX);
+
+	} else if (fs->ref_count == -1 || mode & FMODE_EXCL)
+		return -EBUSY;
+
+	if (err == 0 && (mode & FMODE_NDELAY) == 0
+	    && (mode & (FMODE_READ|FMODE_WRITE))) {
+		if (bdev_check_media_change(bdev))
+			floppy_revalidate(bdev->bd_disk);
+		if (fs->ejected)
+			err = -ENXIO;
+	}
+
+	if (err == 0 && (mode & FMODE_WRITE)) {
+		if (fs->write_prot < 0)
+			fs->write_prot = swim3_readbit(fs, WRITE_PROT);
+		if (fs->write_prot)
+			err = -EROFS;
+	}
+
+	if (err) {
+		if (fs->ref_count == 0) {
+			swim3_action(fs, MOTOR_OFF);
+			out_8(&sw->control_bic, DRIVE_ENABLE | INTR_ENABLE);
+			swim3_select(fs, RELAX);
+		}
+		return err;
+	}
+
+	if (mode & FMODE_EXCL)
+		fs->ref_count = -1;
+	else
+		++fs->ref_count;
+
+	return 0;
+}
+
+static int floppy_unlocked_open(struct block_device *bdev, fmode_t mode)
+{
+	int ret;
+
+	mutex_lock(&swim3_mutex);
+	ret = floppy_open(bdev, mode);
+	mutex_unlock(&swim3_mutex);
+
+	return ret;
+}
+
+static void floppy_release(struct gendisk *disk, fmode_t mode)
+{
+	struct floppy_state *fs = disk->private_data;
+	struct swim3 __iomem *sw = fs->swim3;
+
+	mutex_lock(&swim3_mutex);
+	if (fs->ref_count > 0)
+		--fs->ref_count;
+	else if (fs->ref_count == -1)
+		fs->ref_count = 0;
+	if (fs->ref_count == 0) {
+		swim3_action(fs, MOTOR_OFF);
+		out_8(&sw->control_bic, 0xff);
+		swim3_select(fs, RELAX);
+	}
+	mutex_unlock(&swim3_mutex);
+}
+
+static unsigned int floppy_check_events(struct gendisk *disk,
+					unsigned int clearing)
+{
+	struct floppy_state *fs = disk->private_data;
+	return fs->ejected ? DISK_EVENT_MEDIA_CHANGE : 0;
+}
+
+static int floppy_revalidate(struct gendisk *disk)
+{
+	struct floppy_state *fs = disk->private_data;
+	struct swim3 __iomem *sw;
+	int ret, n;
+
+	if (fs->mdev->media_bay &&
+	    check_media_bay(fs->mdev->media_bay) != MB_FD)
+		return -ENXIO;
+
+	sw = fs->swim3;
+	grab_drive(fs, revalidating, 0);
+	out_8(&sw->intr_enable, 0);
+	out_8(&sw->control_bis, DRIVE_ENABLE);
+	swim3_action(fs, MOTOR_ON);	/* necessary? */
+	fs->write_prot = -1;
+	fs->cur_cyl = -1;
+	mdelay(1);
+	for (n = HZ; n > 0; --n) {
+		if (swim3_readbit(fs, SEEK_COMPLETE))
+			break;
+		if (signal_pending(current))
+			break;
+		swim3_select(fs, RELAX);
+		schedule_timeout_interruptible(1);
+	}
+	ret = swim3_readbit(fs, SEEK_COMPLETE) == 0
+		|| swim3_readbit(fs, DISK_IN) == 0;
+	if (ret)
+		swim3_action(fs, MOTOR_OFF);
+	else {
+		fs->ejected = 0;
+		swim3_action(fs, SETMFM);
+	}
+	swim3_select(fs, RELAX);
+
+	release_drive(fs);
+	return ret;
+}
+
+static const struct block_device_operations floppy_fops = {
+	.open		= floppy_unlocked_open,
+	.release	= floppy_release,
+	.ioctl		= floppy_ioctl,
+	.check_events	= floppy_check_events,
+};
+
+static const struct blk_mq_ops swim3_mq_ops = {
+	.queue_rq = swim3_queue_rq,
+};
+
+static void swim3_mb_event(struct macio_dev* mdev, int mb_state)
+{
+	struct floppy_state *fs = macio_get_drvdata(mdev);
+	struct swim3 __iomem *sw;
+
+	if (!fs)
+		return;
+
+	sw = fs->swim3;
+
+	if (mb_state != MB_FD)
+		return;
+
+	/* Clear state */
+	out_8(&sw->intr_enable, 0);
+	in_8(&sw->intr);
+	in_8(&sw->error);
+}
+
+static int swim3_add_device(struct macio_dev *mdev, int index)
+{
+	struct device_node *swim = mdev->ofdev.dev.of_node;
+	struct floppy_state *fs = &floppy_states[index];
+	int rc = -EBUSY;
+
+	fs->mdev = mdev;
+	fs->index = index;
+
+	/* Check & Request resources */
+	if (macio_resource_count(mdev) < 2) {
+		swim3_err("%s", "No address in device-tree\n");
+		return -ENXIO;
+	}
+	if (macio_irq_count(mdev) < 1) {
+		swim3_err("%s", "No interrupt in device-tree\n");
+		return -ENXIO;
+	}
+	if (macio_request_resource(mdev, 0, "swim3 (mmio)")) {
+		swim3_err("%s", "Can't request mmio resource\n");
+		return -EBUSY;
+	}
+	if (macio_request_resource(mdev, 1, "swim3 (dma)")) {
+		swim3_err("%s", "Can't request dma resource\n");
+		macio_release_resource(mdev, 0);
+		return -EBUSY;
+	}
+	dev_set_drvdata(&mdev->ofdev.dev, fs);
+
+	if (mdev->media_bay == NULL)
+		pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 1);
+	
+	fs->state = idle;
+	fs->swim3 = (struct swim3 __iomem *)
+		ioremap(macio_resource_start(mdev, 0), 0x200);
+	if (fs->swim3 == NULL) {
+		swim3_err("%s", "Couldn't map mmio registers\n");
+		rc = -ENOMEM;
+		goto out_release;
+	}
+	fs->dma = (struct dbdma_regs __iomem *)
+		ioremap(macio_resource_start(mdev, 1), 0x200);
+	if (fs->dma == NULL) {
+		swim3_err("%s", "Couldn't map dma registers\n");
+		iounmap(fs->swim3);
+		rc = -ENOMEM;
+		goto out_release;
+	}
+	fs->swim3_intr = macio_irq(mdev, 0);
+	fs->dma_intr = macio_irq(mdev, 1);
+	fs->cur_cyl = -1;
+	fs->cur_sector = -1;
+	fs->secpercyl = 36;
+	fs->secpertrack = 18;
+	fs->total_secs = 2880;
+	init_waitqueue_head(&fs->wait);
+
+	fs->dma_cmd = (struct dbdma_cmd *) DBDMA_ALIGN(fs->dbdma_cmd_space);
+	memset(fs->dma_cmd, 0, 2 * sizeof(struct dbdma_cmd));
+	fs->dma_cmd[1].command = cpu_to_le16(DBDMA_STOP);
+
+	if (mdev->media_bay == NULL || check_media_bay(mdev->media_bay) == MB_FD)
+		swim3_mb_event(mdev, MB_FD);
+
+	if (request_irq(fs->swim3_intr, swim3_interrupt, 0, "SWIM3", fs)) {
+		swim3_err("%s", "Couldn't request interrupt\n");
+		pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 0);
+		goto out_unmap;
+	}
+
+	timer_setup(&fs->timeout, NULL, 0);
+
+	swim3_info("SWIM3 floppy controller %s\n",
+		mdev->media_bay ? "in media bay" : "");
+
+	return 0;
+
+ out_unmap:
+	iounmap(fs->dma);
+	iounmap(fs->swim3);
+
+ out_release:
+	macio_release_resource(mdev, 0);
+	macio_release_resource(mdev, 1);
+
+	return rc;
+}
+
+static int swim3_attach(struct macio_dev *mdev,
+			const struct of_device_id *match)
+{
+	struct floppy_state *fs;
+	struct gendisk *disk;
+	int rc;
+
+	if (floppy_count >= MAX_FLOPPIES)
+		return -ENXIO;
+
+	if (floppy_count == 0) {
+		rc = register_blkdev(FLOPPY_MAJOR, "fd");
+		if (rc)
+			return rc;
+	}
+
+	disk = alloc_disk(1);
+	if (disk == NULL) {
+		rc = -ENOMEM;
+		goto out_unregister;
+	}
+
+	fs = &floppy_states[floppy_count];
+	memset(fs, 0, sizeof(*fs));
+
+	disk->queue = blk_mq_init_sq_queue(&fs->tag_set, &swim3_mq_ops, 2,
+						BLK_MQ_F_SHOULD_MERGE);
+	if (IS_ERR(disk->queue)) {
+		rc = PTR_ERR(disk->queue);
+		disk->queue = NULL;
+		goto out_put_disk;
+	}
+	blk_queue_bounce_limit(disk->queue, BLK_BOUNCE_HIGH);
+	disk->queue->queuedata = fs;
+
+	rc = swim3_add_device(mdev, floppy_count);
+	if (rc)
+		goto out_cleanup_queue;
+
+	disk->major = FLOPPY_MAJOR;
+	disk->first_minor = floppy_count;
+	disk->fops = &floppy_fops;
+	disk->private_data = fs;
+	disk->events = DISK_EVENT_MEDIA_CHANGE;
+	disk->flags |= GENHD_FL_REMOVABLE;
+	sprintf(disk->disk_name, "fd%d", floppy_count);
+	set_capacity(disk, 2880);
+	add_disk(disk);
+
+	disks[floppy_count++] = disk;
+	return 0;
+
+out_cleanup_queue:
+	blk_cleanup_queue(disk->queue);
+	disk->queue = NULL;
+	blk_mq_free_tag_set(&fs->tag_set);
+out_put_disk:
+	put_disk(disk);
+out_unregister:
+	if (floppy_count == 0)
+		unregister_blkdev(FLOPPY_MAJOR, "fd");
+	return rc;
+}
+
+static const struct of_device_id swim3_match[] =
+{
+	{
+	.name		= "swim3",
+	},
+	{
+	.compatible	= "ohare-swim3"
+	},
+	{
+	.compatible	= "swim3"
+	},
+	{ /* end of list */ }
+};
+
+static struct macio_driver swim3_driver =
+{
+	.driver = {
+		.name 		= "swim3",
+		.of_match_table	= swim3_match,
+	},
+	.probe		= swim3_attach,
+#ifdef CONFIG_PMAC_MEDIABAY
+	.mediabay_event	= swim3_mb_event,
+#endif
+#if 0
+	.suspend	= swim3_suspend,
+	.resume		= swim3_resume,
+#endif
+};
+
+
+int swim3_init(void)
+{
+	macio_register_driver(&swim3_driver);
+	return 0;
+}
+
+module_init(swim3_init)
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Paul Mackerras");
+MODULE_ALIAS_BLOCKDEV_MAJOR(FLOPPY_MAJOR);