[net-next-2.6.git] / drivers / scsi / mac53c94.c

/*
 * SCSI low-level driver for the 53c94 SCSI bus adaptor found
 * on Power Macintosh computers, controlling the external SCSI chain.
 * We assume the 53c94 is connected to a DBDMA (descriptor-based DMA)
 * controller.
 *
 * Paul Mackerras, August 1996.
 * Copyright (C) 1996 Paul Mackerras.
 */
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/blkdev.h>
#include <linux/proc_fs.h>
#include <linux/stat.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <asm/dbdma.h>
#include <asm/io.h>
#include <asm/pgtable.h>
#include <asm/prom.h>
#include <asm/system.h>
#include <asm/pci-bridge.h>
#include <asm/macio.h>

#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>

#include "mac53c94.h"

enum fsc_phase {
	idle,
	selecting,
	dataing,
	completing,
	busfreeing,
};

struct fsc_state {
	struct	mac53c94_regs __iomem *regs;
	int	intr;
	struct	dbdma_regs __iomem *dma;
	int	dmaintr;
	int	clk_freq;
	struct	Scsi_Host *host;
	struct scsi_cmnd *request_q;
	struct scsi_cmnd *request_qtail;
	struct scsi_cmnd *current_req;		/* req we're currently working on */
	enum fsc_phase phase;		/* what we're currently trying to do */
	struct dbdma_cmd *dma_cmds;	/* space for dbdma commands, aligned */
	void	*dma_cmd_space;
	struct	pci_dev *pdev;
	dma_addr_t dma_addr;
	struct macio_dev *mdev;
};

static void mac53c94_init(struct fsc_state *);
static void mac53c94_start(struct fsc_state *);
static void mac53c94_interrupt(int, void *);
static irqreturn_t do_mac53c94_interrupt(int, void *);
static void cmd_done(struct fsc_state *, int result);
static void set_dma_cmds(struct fsc_state *, struct scsi_cmnd *);


static int mac53c94_queue(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
{
	struct fsc_state *state;

#if 0
	if (cmd->sc_data_direction == DMA_TO_DEVICE) {
		int i;
		printk(KERN_DEBUG "mac53c94_queue %p: command is", cmd);
		for (i = 0; i < cmd->cmd_len; ++i)
			printk(KERN_CONT " %.2x", cmd->cmnd[i]);
		printk(KERN_CONT "\n");
		printk(KERN_DEBUG "use_sg=%d request_bufflen=%d request_buffer=%p\n",
		       scsi_sg_count(cmd), scsi_bufflen(cmd), scsi_sglist(cmd));
	}
#endif

	cmd->scsi_done = done;
	cmd->host_scribble = NULL;

	state = (struct fsc_state *) cmd->device->host->hostdata;

	if (state->request_q == NULL)
		state->request_q = cmd;
	else
		state->request_qtail->host_scribble = (void *) cmd;
	state->request_qtail = cmd;

	if (state->phase == idle)
		mac53c94_start(state);

	return 0;
}

static int mac53c94_host_reset(struct scsi_cmnd *cmd)
{
	struct fsc_state *state = (struct fsc_state *) cmd->device->host->hostdata;
	struct mac53c94_regs __iomem *regs = state->regs;
	struct dbdma_regs __iomem *dma = state->dma;
	unsigned long flags;

	spin_lock_irqsave(cmd->device->host->host_lock, flags);

	writel((RUN|PAUSE|FLUSH|WAKE) << 16, &dma->control);
	writeb(CMD_SCSI_RESET, &regs->command);	/* assert RST */
	udelay(100);			/* leave it on for a while (>= 25us) */
	writeb(CMD_RESET, &regs->command);
	udelay(20);
	mac53c94_init(state);
	writeb(CMD_NOP, &regs->command);

	spin_unlock_irqrestore(cmd->device->host->host_lock, flags);
	return SUCCESS;
}

static void mac53c94_init(struct fsc_state *state)
{
	struct mac53c94_regs __iomem *regs = state->regs;
	struct dbdma_regs __iomem *dma = state->dma;
	int x;

	writeb(state->host->this_id | CF1_PAR_ENABLE, &regs->config1);
	writeb(TIMO_VAL(250), &regs->sel_timeout);	/* 250ms */
	writeb(CLKF_VAL(state->clk_freq), &regs->clk_factor);
	writeb(CF2_FEATURE_EN, &regs->config2);
	writeb(0, &regs->config3);
	writeb(0, &regs->sync_period);
	writeb(0, &regs->sync_offset);
	x = readb(&regs->interrupt);
	writel((RUN|PAUSE|FLUSH|WAKE) << 16, &dma->control);
}

/*
 * Start the next command for a 53C94.
 * Should be called with interrupts disabled.
 */
static void mac53c94_start(struct fsc_state *state)
{
	struct scsi_cmnd *cmd;
	struct mac53c94_regs __iomem *regs = state->regs;
	int i;

	if (state->phase != idle || state->current_req != NULL)
		panic("inappropriate mac53c94_start (state=%p)", state);
	if (state->request_q == NULL)
		return;
	state->current_req = cmd = state->request_q;
	state->request_q = (struct scsi_cmnd *) cmd->host_scribble;

	/* Off we go */
	writeb(0, &regs->count_lo);
	writeb(0, &regs->count_mid);
	writeb(0, &regs->count_hi);
	writeb(CMD_NOP + CMD_DMA_MODE, &regs->command);
	udelay(1);
	writeb(CMD_FLUSH, &regs->command);
	udelay(1);
	writeb(cmd->device->id, &regs->dest_id);
	writeb(0, &regs->sync_period);
	writeb(0, &regs->sync_offset);

	/* load the command into the FIFO */
	for (i = 0; i < cmd->cmd_len; ++i)
		writeb(cmd->cmnd[i], &regs->fifo);

	/* do select without ATN XXX */
	writeb(CMD_SELECT, &regs->command);
	state->phase = selecting;

	set_dma_cmds(state, cmd);
}

static irqreturn_t do_mac53c94_interrupt(int irq, void *dev_id)
{
	unsigned long flags;
	struct Scsi_Host *dev = ((struct fsc_state *) dev_id)->current_req->device->host;
	
	spin_lock_irqsave(dev->host_lock, flags);
	mac53c94_interrupt(irq, dev_id);
	spin_unlock_irqrestore(dev->host_lock, flags);
	return IRQ_HANDLED;
}

static void mac53c94_interrupt(int irq, void *dev_id)
{
	struct fsc_state *state = (struct fsc_state *) dev_id;
	struct mac53c94_regs __iomem *regs = state->regs;
	struct dbdma_regs __iomem *dma = state->dma;
	struct scsi_cmnd *cmd = state->current_req;
	int nb, stat, seq, intr;
	static int mac53c94_errors;

	/*
	 * Apparently, reading the interrupt register unlatches
	 * the status and sequence step registers.
	 */
	seq = readb(&regs->seqstep);
	stat = readb(&regs->status);
	intr = readb(&regs->interrupt);

#if 0
	printk(KERN_DEBUG "mac53c94_intr, intr=%x stat=%x seq=%x phase=%d\n",
	       intr, stat, seq, state->phase);
#endif

	if (intr & INTR_RESET) {
		/* SCSI bus was reset */
		printk(KERN_INFO "external SCSI bus reset detected\n");
		writeb(CMD_NOP, &regs->command);
		writel(RUN << 16, &dma->control);	/* stop dma */
		cmd_done(state, DID_RESET << 16);
		return;
	}
	if (intr & INTR_ILL_CMD) {
		printk(KERN_ERR "53c94: invalid cmd, intr=%x stat=%x seq=%x phase=%d\n",
		       intr, stat, seq, state->phase);
		cmd_done(state, DID_ERROR << 16);
		return;
	}
	if (stat & STAT_ERROR) {
#if 0
		/* XXX these seem to be harmless? */
		printk("53c94: bad error, intr=%x stat=%x seq=%x phase=%d\n",
		       intr, stat, seq, state->phase);
#endif
		++mac53c94_errors;
		writeb(CMD_NOP + CMD_DMA_MODE, &regs->command);
	}
	if (cmd == 0) {
		printk(KERN_DEBUG "53c94: interrupt with no command active?\n");
		return;
	}
	if (stat & STAT_PARITY) {
		printk(KERN_ERR "mac53c94: parity error\n");
		cmd_done(state, DID_PARITY << 16);
		return;
	}
	switch (state->phase) {
	case selecting:
		if (intr & INTR_DISCONNECT) {
			/* selection timed out */
			cmd_done(state, DID_BAD_TARGET << 16);
			return;
		}
		if (intr != INTR_BUS_SERV + INTR_DONE) {
			printk(KERN_DEBUG "got intr %x during selection\n", intr);
			cmd_done(state, DID_ERROR << 16);
			return;
		}
		if ((seq & SS_MASK) != SS_DONE) {
			printk(KERN_DEBUG "seq step %x after command\n", seq);
			cmd_done(state, DID_ERROR << 16);
			return;
		}
		writeb(CMD_NOP, &regs->command);
		/* set DMA controller going if any data to transfer */
		if ((stat & (STAT_MSG|STAT_CD)) == 0
		    && (scsi_sg_count(cmd) > 0 || scsi_bufflen(cmd))) {
			nb = cmd->SCp.this_residual;
			if (nb > 0xfff0)
				nb = 0xfff0;
			cmd->SCp.this_residual -= nb;
			writeb(nb, &regs->count_lo);
			writeb(nb >> 8, &regs->count_mid);
			writeb(CMD_DMA_MODE + CMD_NOP, &regs->command);
			writel(virt_to_phys(state->dma_cmds), &dma->cmdptr);
			writel((RUN << 16) | RUN, &dma->control);
			writeb(CMD_DMA_MODE + CMD_XFER_DATA, &regs->command);
			state->phase = dataing;
			break;
		} else if ((stat & STAT_PHASE) == STAT_CD + STAT_IO) {
			/* up to status phase already */
			writeb(CMD_I_COMPLETE, &regs->command);
			state->phase = completing;
		} else {
			printk(KERN_DEBUG "in unexpected phase %x after cmd\n",
			       stat & STAT_PHASE);
			cmd_done(state, DID_ERROR << 16);
			return;
		}
		break;

	case dataing:
		if (intr != INTR_BUS_SERV) {
			printk(KERN_DEBUG "got intr %x before status\n", intr);
			cmd_done(state, DID_ERROR << 16);
			return;
		}
		if (cmd->SCp.this_residual != 0
		    && (stat & (STAT_MSG|STAT_CD)) == 0) {
			/* Set up the count regs to transfer more */
			nb = cmd->SCp.this_residual;
			if (nb > 0xfff0)
				nb = 0xfff0;
			cmd->SCp.this_residual -= nb;
			writeb(nb, &regs->count_lo);
			writeb(nb >> 8, &regs->count_mid);
			writeb(CMD_DMA_MODE + CMD_NOP, &regs->command);
			writeb(CMD_DMA_MODE + CMD_XFER_DATA, &regs->command);
			break;
		}
		if ((stat & STAT_PHASE) != STAT_CD + STAT_IO) {
			printk(KERN_DEBUG "intr %x before data xfer complete\n", intr);
		}
		writel(RUN << 16, &dma->control);	/* stop dma */
		scsi_dma_unmap(cmd);
		/* should check dma status */
		writeb(CMD_I_COMPLETE, &regs->command);
		state->phase = completing;
		break;
	case completing:
		if (intr != INTR_DONE) {
			printk(KERN_DEBUG "got intr %x on completion\n", intr);
			cmd_done(state, DID_ERROR << 16);
			return;
		}
		cmd->SCp.Status = readb(&regs->fifo);
		cmd->SCp.Message = readb(&regs->fifo);
		cmd->result = CMD_ACCEPT_MSG;
		writeb(CMD_ACCEPT_MSG, &regs->command);
		state->phase = busfreeing;
		break;
	case busfreeing:
		if (intr != INTR_DISCONNECT) {
			printk(KERN_DEBUG "got intr %x when expected disconnect\n", intr);
		}
		cmd_done(state, (DID_OK << 16) + (cmd->SCp.Message << 8)
			 + cmd->SCp.Status);
		break;
	default:
		printk(KERN_DEBUG "don't know about phase %d\n", state->phase);
	}
}

static void cmd_done(struct fsc_state *state, int result)
{
	struct scsi_cmnd *cmd;

	cmd = state->current_req;
	if (cmd != 0) {
		cmd->result = result;
		(*cmd->scsi_done)(cmd);
		state->current_req = NULL;
	}
	state->phase = idle;
	mac53c94_start(state);
}

/*
 * Set up DMA commands for transferring data.
 */
static void set_dma_cmds(struct fsc_state *state, struct scsi_cmnd *cmd)
{
	int i, dma_cmd, total, nseg;
	struct scatterlist *scl;
	struct dbdma_cmd *dcmds;
	dma_addr_t dma_addr;
	u32 dma_len;

	nseg = scsi_dma_map(cmd);
	BUG_ON(nseg < 0);
	if (!nseg)
		return;

	dma_cmd = cmd->sc_data_direction == DMA_TO_DEVICE ?
			OUTPUT_MORE : INPUT_MORE;
	dcmds = state->dma_cmds;
	total = 0;

	scsi_for_each_sg(cmd, scl, nseg, i) {
		dma_addr = sg_dma_address(scl);
		dma_len = sg_dma_len(scl);
		if (dma_len > 0xffff)
			panic("mac53c94: scatterlist element >= 64k");
		total += dma_len;
		st_le16(&dcmds->req_count, dma_len);
		st_le16(&dcmds->command, dma_cmd);
		st_le32(&dcmds->phy_addr, dma_addr);
		dcmds->xfer_status = 0;
		++dcmds;
	}

	dma_cmd += OUTPUT_LAST - OUTPUT_MORE;
	st_le16(&dcmds[-1].command, dma_cmd);
	st_le16(&dcmds->command, DBDMA_STOP);
	cmd->SCp.this_residual = total;
}

static struct scsi_host_template mac53c94_template = {
	.proc_name	= "53c94",
	.name		= "53C94",
	.queuecommand	= mac53c94_queue,
	.eh_host_reset_handler = mac53c94_host_reset,
	.can_queue	= 1,
	.this_id	= 7,
	.sg_tablesize	= SG_ALL,
	.cmd_per_lun	= 1,
	.use_clustering	= DISABLE_CLUSTERING,
};

static int mac53c94_probe(struct macio_dev *mdev, const struct of_device_id *match)
{
	struct device_node *node = macio_get_of_node(mdev);
	struct pci_dev *pdev = macio_get_pci_dev(mdev);
	struct fsc_state *state;
	struct Scsi_Host *host;
	void *dma_cmd_space;
	const unsigned char *clkprop;
	int proplen, rc = -ENODEV;

	if (macio_resource_count(mdev) != 2 || macio_irq_count(mdev) != 2) {
		printk(KERN_ERR "mac53c94: expected 2 addrs and intrs"
		       " (got %d/%d)\n",
		       macio_resource_count(mdev), macio_irq_count(mdev));
		return -ENODEV;
	}

	if (macio_request_resources(mdev, "mac53c94") != 0) {
       		printk(KERN_ERR "mac53c94: unable to request memory resources");
		return -EBUSY;
	}

       	host = scsi_host_alloc(&mac53c94_template, sizeof(struct fsc_state));
	if (host == NULL) {
		printk(KERN_ERR "mac53c94: couldn't register host");
		rc = -ENOMEM;
		goto out_release;
	}

	state = (struct fsc_state *) host->hostdata;
	macio_set_drvdata(mdev, state);
	state->host = host;
	state->pdev = pdev;
	state->mdev = mdev;

	state->regs = (struct mac53c94_regs __iomem *)
		ioremap(macio_resource_start(mdev, 0), 0x1000);
	state->intr = macio_irq(mdev, 0);
	state->dma = (struct dbdma_regs __iomem *)
		ioremap(macio_resource_start(mdev, 1), 0x1000);
	state->dmaintr = macio_irq(mdev, 1);
	if (state->regs == NULL || state->dma == NULL) {
		printk(KERN_ERR "mac53c94: ioremap failed for %s\n",
		       node->full_name);
		goto out_free;
	}

	clkprop = of_get_property(node, "clock-frequency", &proplen);
       	if (clkprop == NULL || proplen != sizeof(int)) {
       		printk(KERN_ERR "%s: can't get clock frequency, "
       		       "assuming 25MHz\n", node->full_name);
       		state->clk_freq = 25000000;
       	} else
       		state->clk_freq = *(int *)clkprop;

       	/* Space for dma command list: +1 for stop command,
       	 * +1 to allow for aligning.
	 * XXX FIXME: Use DMA consistent routines
	 */
       	dma_cmd_space = kmalloc((host->sg_tablesize + 2) *
       				sizeof(struct dbdma_cmd), GFP_KERNEL);
       	if (dma_cmd_space == 0) {
       		printk(KERN_ERR "mac53c94: couldn't allocate dma "
       		       "command space for %s\n", node->full_name);
		rc = -ENOMEM;
       		goto out_free;
       	}
	state->dma_cmds = (struct dbdma_cmd *)DBDMA_ALIGN(dma_cmd_space);
	memset(state->dma_cmds, 0, (host->sg_tablesize + 1)
	       * sizeof(struct dbdma_cmd));
	state->dma_cmd_space = dma_cmd_space;

	mac53c94_init(state);

	if (request_irq(state->intr, do_mac53c94_interrupt, 0, "53C94",state)) {
		printk(KERN_ERR "mac53C94: can't get irq %d for %s\n",
		       state->intr, node->full_name);
		goto out_free_dma;
	}

	rc = scsi_add_host(host, &mdev->ofdev.dev);
	if (rc != 0)
		goto out_release_irq;

	scsi_scan_host(host);
	return 0;

 out_release_irq:
	free_irq(state->intr, state);
 out_free_dma:
	kfree(state->dma_cmd_space);
 out_free:
	if (state->dma != NULL)
		iounmap(state->dma);
	if (state->regs != NULL)
		iounmap(state->regs);
	scsi_host_put(host);
 out_release:
	macio_release_resources(mdev);

	return rc;
}

static int mac53c94_remove(struct macio_dev *mdev)
{
	struct fsc_state *fp = (struct fsc_state *)macio_get_drvdata(mdev);
	struct Scsi_Host *host = fp->host;

	scsi_remove_host(host);

	free_irq(fp->intr, fp);

	if (fp->regs)
		iounmap(fp->regs);
	if (fp->dma)
		iounmap(fp->dma);
	kfree(fp->dma_cmd_space);

	scsi_host_put(host);

	macio_release_resources(mdev);

	return 0;
}


static struct of_device_id mac53c94_match[] = 
{
	{
	.name 		= "53c94",
	},
	{},
};
MODULE_DEVICE_TABLE (of, mac53c94_match);

static struct macio_driver mac53c94_driver = 
{
	.driver = {
		.name 		= "mac53c94",
		.owner		= THIS_MODULE,
		.of_match_table	= mac53c94_match,
	},
	.probe		= mac53c94_probe,
	.remove		= mac53c94_remove,
};


static int __init init_mac53c94(void)
{
	return macio_register_driver(&mac53c94_driver);
}

static void __exit exit_mac53c94(void)
{
	return macio_unregister_driver(&mac53c94_driver);
}

module_init(init_mac53c94);
module_exit(exit_mac53c94);

MODULE_DESCRIPTION("PowerMac 53c94 SCSI driver");
MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
MODULE_LICENSE("GPL");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* SCSI low-level driver for the 53c94 SCSI bus adaptor found
	3	* on Power Macintosh computers, controlling the external SCSI chain.
	4	* We assume the 53c94 is connected to a DBDMA (descriptor-based DMA)
	5	* controller.
	6	*
	7	* Paul Mackerras, August 1996.
	8	* Copyright (C) 1996 Paul Mackerras.
	9	*/
	10	#include <linux/kernel.h>
	11	#include <linux/delay.h>
	12	#include <linux/types.h>
	13	#include <linux/string.h>
	14	#include <linux/slab.h>
	15	#include <linux/blkdev.h>
	16	#include <linux/proc_fs.h>
	17	#include <linux/stat.h>
	18	#include <linux/spinlock.h>
	19	#include <linux/interrupt.h>
	20	#include <asm/dbdma.h>
	21	#include <asm/io.h>
	22	#include <asm/pgtable.h>
	23	#include <asm/prom.h>
	24	#include <asm/system.h>
	25	#include <asm/pci-bridge.h>
	26	#include <asm/macio.h>
	27
	28	#include <scsi/scsi.h>
	29	#include <scsi/scsi_cmnd.h>
	30	#include <scsi/scsi_device.h>
	31	#include <scsi/scsi_host.h>
	32
	33	#include "mac53c94.h"
	34
	35	enum fsc_phase {
	36	idle,
	37	selecting,
	38	dataing,
	39	completing,
	40	busfreeing,
	41	};
	42
	43	struct fsc_state {
	44	struct mac53c94_regs __iomem *regs;
	45	int intr;
	46	struct dbdma_regs __iomem *dma;
	47	int dmaintr;
	48	int clk_freq;
	49	struct Scsi_Host *host;
	50	struct scsi_cmnd *request_q;
	51	struct scsi_cmnd *request_qtail;
	52	struct scsi_cmnd current_req; / req we're currently working on */
	53	enum fsc_phase phase; /* what we're currently trying to do */
	54	struct dbdma_cmd dma_cmds; / space for dbdma commands, aligned */
	55	void *dma_cmd_space;
	56	struct pci_dev *pdev;
	57	dma_addr_t dma_addr;
	58	struct macio_dev *mdev;
	59	};
	60
	61	static void mac53c94_init(struct fsc_state *);
	62	static void mac53c94_start(struct fsc_state *);
7d12e780 DH	63	static void mac53c94_interrupt(int, void *);
7d12e780 DH	64	static irqreturn_t do_mac53c94_interrupt(int, void *);
1da177e4 LT	65	static void cmd_done(struct fsc_state *, int result);
	66	static void set_dma_cmds(struct fsc_state , struct scsi_cmnd );
	67
	68
	69	static int mac53c94_queue(struct scsi_cmnd cmd, void (done)(struct scsi_cmnd *))
	70	{
	71	struct fsc_state *state;
	72
	73	#if 0
	74	if (cmd->sc_data_direction == DMA_TO_DEVICE) {
	75	int i;
	76	printk(KERN_DEBUG "mac53c94_queue %p: command is", cmd);
	77	for (i = 0; i < cmd->cmd_len; ++i)
ad361c98 JP	78	printk(KERN_CONT " %.2x", cmd->cmnd[i]);
	79	printk(KERN_CONT "\n");
	80	printk(KERN_DEBUG "use_sg=%d request_bufflen=%d request_buffer=%p\n",
646158c2	81	scsi_sg_count(cmd), scsi_bufflen(cmd), scsi_sglist(cmd));
1da177e4 LT	82	}
	83	#endif
	84
	85	cmd->scsi_done = done;
	86	cmd->host_scribble = NULL;
	87
	88	state = (struct fsc_state *) cmd->device->host->hostdata;
	89
	90	if (state->request_q == NULL)
	91	state->request_q = cmd;
	92	else
	93	state->request_qtail->host_scribble = (void *) cmd;
	94	state->request_qtail = cmd;
	95
	96	if (state->phase == idle)
	97	mac53c94_start(state);
	98
	99	return 0;
	100	}
	101
1da177e4 LT	102	static int mac53c94_host_reset(struct scsi_cmnd *cmd)
	103	{
	104	struct fsc_state state = (struct fsc_state ) cmd->device->host->hostdata;
	105	struct mac53c94_regs __iomem *regs = state->regs;
	106	struct dbdma_regs __iomem *dma = state->dma;
df0ae249 JG	107	unsigned long flags;
	108
	109	spin_lock_irqsave(cmd->device->host->host_lock, flags);
1da177e4 LT	110
	111	writel((RUN\|PAUSE\|FLUSH\|WAKE) << 16, &dma->control);
	112	writeb(CMD_SCSI_RESET, &regs->command); /* assert RST */
	113	udelay(100); /* leave it on for a while (>= 25us) */
	114	writeb(CMD_RESET, &regs->command);
	115	udelay(20);
	116	mac53c94_init(state);
	117	writeb(CMD_NOP, &regs->command);
df0ae249 JG	118
df0ae249 JG	119	spin_unlock_irqrestore(cmd->device->host->host_lock, flags);
1da177e4 LT	120	return SUCCESS;
	121	}
	122
	123	static void mac53c94_init(struct fsc_state *state)
	124	{
	125	struct mac53c94_regs __iomem *regs = state->regs;
	126	struct dbdma_regs __iomem *dma = state->dma;
	127	int x;
	128
	129	writeb(state->host->this_id \| CF1_PAR_ENABLE, &regs->config1);
	130	writeb(TIMO_VAL(250), &regs->sel_timeout); /* 250ms */
	131	writeb(CLKF_VAL(state->clk_freq), &regs->clk_factor);
	132	writeb(CF2_FEATURE_EN, &regs->config2);
	133	writeb(0, &regs->config3);
	134	writeb(0, &regs->sync_period);
	135	writeb(0, &regs->sync_offset);
	136	x = readb(&regs->interrupt);
	137	writel((RUN\|PAUSE\|FLUSH\|WAKE) << 16, &dma->control);
	138	}
	139
	140	/*
	141	* Start the next command for a 53C94.
	142	* Should be called with interrupts disabled.
	143	*/
	144	static void mac53c94_start(struct fsc_state *state)
	145	{
	146	struct scsi_cmnd *cmd;
	147	struct mac53c94_regs __iomem *regs = state->regs;
	148	int i;
	149
	150	if (state->phase != idle \|\| state->current_req != NULL)
	151	panic("inappropriate mac53c94_start (state=%p)", state);
	152	if (state->request_q == NULL)
	153	return;
	154	state->current_req = cmd = state->request_q;
	155	state->request_q = (struct scsi_cmnd *) cmd->host_scribble;
	156
	157	/* Off we go */
	158	writeb(0, &regs->count_lo);
	159	writeb(0, &regs->count_mid);
	160	writeb(0, &regs->count_hi);
	161	writeb(CMD_NOP + CMD_DMA_MODE, &regs->command);
	162	udelay(1);
	163	writeb(CMD_FLUSH, &regs->command);
	164	udelay(1);
	165	writeb(cmd->device->id, &regs->dest_id);
	166	writeb(0, &regs->sync_period);
	167	writeb(0, &regs->sync_offset);
	168
	169	/* load the command into the FIFO */
	170	for (i = 0; i < cmd->cmd_len; ++i)
	171	writeb(cmd->cmnd[i], &regs->fifo);
	172
	173	/* do select without ATN XXX */
	174	writeb(CMD_SELECT, &regs->command);
	175	state->phase = selecting;
	176
646158c2	177	set_dma_cmds(state, cmd);
1da177e4 LT	178	}
1da177e4 LT	179
7d12e780	180	static irqreturn_t do_mac53c94_interrupt(int irq, void *dev_id)
1da177e4 LT	181	{
	182	unsigned long flags;
	183	struct Scsi_Host dev = ((struct fsc_state ) dev_id)->current_req->device->host;
	184
	185	spin_lock_irqsave(dev->host_lock, flags);
7d12e780	186	mac53c94_interrupt(irq, dev_id);
1da177e4 LT	187	spin_unlock_irqrestore(dev->host_lock, flags);
	188	return IRQ_HANDLED;
	189	}
	190
7d12e780	191	static void mac53c94_interrupt(int irq, void *dev_id)
1da177e4 LT	192	{
	193	struct fsc_state state = (struct fsc_state ) dev_id;
	194	struct mac53c94_regs __iomem *regs = state->regs;
	195	struct dbdma_regs __iomem *dma = state->dma;
	196	struct scsi_cmnd *cmd = state->current_req;
	197	int nb, stat, seq, intr;
	198	static int mac53c94_errors;
	199
	200	/*
	201	* Apparently, reading the interrupt register unlatches
	202	* the status and sequence step registers.
	203	*/
	204	seq = readb(&regs->seqstep);
	205	stat = readb(&regs->status);
	206	intr = readb(&regs->interrupt);
	207
	208	#if 0
	209	printk(KERN_DEBUG "mac53c94_intr, intr=%x stat=%x seq=%x phase=%d\n",
	210	intr, stat, seq, state->phase);
	211	#endif
	212
	213	if (intr & INTR_RESET) {
	214	/* SCSI bus was reset */
	215	printk(KERN_INFO "external SCSI bus reset detected\n");
	216	writeb(CMD_NOP, &regs->command);
	217	writel(RUN << 16, &dma->control); /* stop dma */
	218	cmd_done(state, DID_RESET << 16);
	219	return;
	220	}
	221	if (intr & INTR_ILL_CMD) {
	222	printk(KERN_ERR "53c94: invalid cmd, intr=%x stat=%x seq=%x phase=%d\n",
	223	intr, stat, seq, state->phase);
	224	cmd_done(state, DID_ERROR << 16);
	225	return;
	226	}
	227	if (stat & STAT_ERROR) {
	228	#if 0
	229	/* XXX these seem to be harmless? */
	230	printk("53c94: bad error, intr=%x stat=%x seq=%x phase=%d\n",
	231	intr, stat, seq, state->phase);
	232	#endif
	233	++mac53c94_errors;
	234	writeb(CMD_NOP + CMD_DMA_MODE, &regs->command);
	235	}
	236	if (cmd == 0) {
	237	printk(KERN_DEBUG "53c94: interrupt with no command active?\n");
	238	return;
	239	}
	240	if (stat & STAT_PARITY) {
	241	printk(KERN_ERR "mac53c94: parity error\n");
	242	cmd_done(state, DID_PARITY << 16);
	243	return;
	244	}
	245	switch (state->phase) {
	246	case selecting:
	247	if (intr & INTR_DISCONNECT) {
	248	/* selection timed out */
	249	cmd_done(state, DID_BAD_TARGET << 16);
	250	return;
	251	}
	252	if (intr != INTR_BUS_SERV + INTR_DONE) {
	253	printk(KERN_DEBUG "got intr %x during selection\n", intr);
	254	cmd_done(state, DID_ERROR << 16);
	255	return;
256	}
257	if ((seq & SS_MASK) != SS_DONE) {
258	printk(KERN_DEBUG "seq step %x after command\n", seq);
259	cmd_done(state, DID_ERROR << 16);
260	return;
261	}
262	writeb(CMD_NOP, &regs->command);
263	/* set DMA controller going if any data to transfer */
264	if ((stat & (STAT_MSG\|STAT_CD)) == 0
646158c2	265	&& (scsi_sg_count(cmd) > 0 \|\| scsi_bufflen(cmd))) {
1da177e4 LT	266	nb = cmd->SCp.this_residual;
	267	if (nb > 0xfff0)
	268	nb = 0xfff0;
	269	cmd->SCp.this_residual -= nb;
	270	writeb(nb, &regs->count_lo);
	271	writeb(nb >> 8, &regs->count_mid);
	272	writeb(CMD_DMA_MODE + CMD_NOP, &regs->command);
	273	writel(virt_to_phys(state->dma_cmds), &dma->cmdptr);
	274	writel((RUN << 16) \| RUN, &dma->control);
	275	writeb(CMD_DMA_MODE + CMD_XFER_DATA, &regs->command);
	276	state->phase = dataing;
	277	break;
	278	} else if ((stat & STAT_PHASE) == STAT_CD + STAT_IO) {
	279	/* up to status phase already */
	280	writeb(CMD_I_COMPLETE, &regs->command);
	281	state->phase = completing;
	282	} else {
	283	printk(KERN_DEBUG "in unexpected phase %x after cmd\n",
	284	stat & STAT_PHASE);
	285	cmd_done(state, DID_ERROR << 16);
	286	return;
	287	}
	288	break;
	289
	290	case dataing:
	291	if (intr != INTR_BUS_SERV) {
	292	printk(KERN_DEBUG "got intr %x before status\n", intr);
	293	cmd_done(state, DID_ERROR << 16);
	294	return;
	295	}
	296	if (cmd->SCp.this_residual != 0
	297	&& (stat & (STAT_MSG\|STAT_CD)) == 0) {
	298	/* Set up the count regs to transfer more */
	299	nb = cmd->SCp.this_residual;
	300	if (nb > 0xfff0)
	301	nb = 0xfff0;
	302	cmd->SCp.this_residual -= nb;
	303	writeb(nb, &regs->count_lo);
	304	writeb(nb >> 8, &regs->count_mid);
	305	writeb(CMD_DMA_MODE + CMD_NOP, &regs->command);
	306	writeb(CMD_DMA_MODE + CMD_XFER_DATA, &regs->command);
	307	break;
	308	}
	309	if ((stat & STAT_PHASE) != STAT_CD + STAT_IO) {
	310	printk(KERN_DEBUG "intr %x before data xfer complete\n", intr);
	311	}
	312	writel(RUN << 16, &dma->control); /* stop dma */
646158c2	313	scsi_dma_unmap(cmd);
1da177e4 LT	314	/* should check dma status */
	315	writeb(CMD_I_COMPLETE, &regs->command);
	316	state->phase = completing;
	317	break;
	318	case completing:
	319	if (intr != INTR_DONE) {
	320	printk(KERN_DEBUG "got intr %x on completion\n", intr);
	321	cmd_done(state, DID_ERROR << 16);
	322	return;
	323	}
	324	cmd->SCp.Status = readb(&regs->fifo);
	325	cmd->SCp.Message = readb(&regs->fifo);
	326	cmd->result = CMD_ACCEPT_MSG;
	327	writeb(CMD_ACCEPT_MSG, &regs->command);
	328	state->phase = busfreeing;
	329	break;
	330	case busfreeing:
	331	if (intr != INTR_DISCONNECT) {
	332	printk(KERN_DEBUG "got intr %x when expected disconnect\n", intr);
	333	}
	334	cmd_done(state, (DID_OK << 16) + (cmd->SCp.Message << 8)
	335	+ cmd->SCp.Status);
	336	break;
	337	default:
	338	printk(KERN_DEBUG "don't know about phase %d\n", state->phase);
	339	}
	340	}
	341
	342	static void cmd_done(struct fsc_state *state, int result)
	343	{
	344	struct scsi_cmnd *cmd;
	345
	346	cmd = state->current_req;
	347	if (cmd != 0) {
	348	cmd->result = result;
	349	(*cmd->scsi_done)(cmd);
	350	state->current_req = NULL;
	351	}
	352	state->phase = idle;
	353	mac53c94_start(state);
	354	}
	355
	356	/*
	357	* Set up DMA commands for transferring data.
	358	*/
	359	static void set_dma_cmds(struct fsc_state state, struct scsi_cmnd cmd)
	360	{
646158c2	361	int i, dma_cmd, total, nseg;
1da177e4 LT	362	struct scatterlist *scl;
	363	struct dbdma_cmd *dcmds;
	364	dma_addr_t dma_addr;
	365	u32 dma_len;
	366
646158c2 FT	367	nseg = scsi_dma_map(cmd);
	368	BUG_ON(nseg < 0);
	369	if (!nseg)
	370	return;
	371
1da177e4 LT	372	dma_cmd = cmd->sc_data_direction == DMA_TO_DEVICE ?
	373	OUTPUT_MORE : INPUT_MORE;
	374	dcmds = state->dma_cmds;
646158c2 FT	375	total = 0;
	376
	377	scsi_for_each_sg(cmd, scl, nseg, i) {
	378	dma_addr = sg_dma_address(scl);
	379	dma_len = sg_dma_len(scl);
	380	if (dma_len > 0xffff)
	381	panic("mac53c94: scatterlist element >= 64k");
	382	total += dma_len;
	383	st_le16(&dcmds->req_count, dma_len);
	384	st_le16(&dcmds->command, dma_cmd);
1da177e4 LT	385	st_le32(&dcmds->phy_addr, dma_addr);
	386	dcmds->xfer_status = 0;
	387	++dcmds;
	388	}
646158c2	389
1da177e4 LT	390	dma_cmd += OUTPUT_LAST - OUTPUT_MORE;
	391	st_le16(&dcmds[-1].command, dma_cmd);
	392	st_le16(&dcmds->command, DBDMA_STOP);
	393	cmd->SCp.this_residual = total;
	394	}
	395
	396	static struct scsi_host_template mac53c94_template = {
	397	.proc_name = "53c94",
	398	.name = "53C94",
	399	.queuecommand = mac53c94_queue,
1da177e4 LT	400	.eh_host_reset_handler = mac53c94_host_reset,
	401	.can_queue = 1,
	402	.this_id = 7,
	403	.sg_tablesize = SG_ALL,
	404	.cmd_per_lun = 1,
	405	.use_clustering = DISABLE_CLUSTERING,
	406	};
	407
5e655772	408	static int mac53c94_probe(struct macio_dev mdev, const struct of_device_id match)
1da177e4 LT	409	{
	410	struct device_node *node = macio_get_of_node(mdev);
	411	struct pci_dev *pdev = macio_get_pci_dev(mdev);
	412	struct fsc_state *state;
	413	struct Scsi_Host *host;
	414	void *dma_cmd_space;
294ef16a	415	const unsigned char *clkprop;
cc5d0189	416	int proplen, rc = -ENODEV;
1da177e4 LT	417
1da177e4 LT	418	if (macio_resource_count(mdev) != 2 \|\| macio_irq_count(mdev) != 2) {
cc5d0189 BH	419	printk(KERN_ERR "mac53c94: expected 2 addrs and intrs"
	420	" (got %d/%d)\n",
	421	macio_resource_count(mdev), macio_irq_count(mdev));
1da177e4 LT	422	return -ENODEV;
	423	}
	424
	425	if (macio_request_resources(mdev, "mac53c94") != 0) {
	426	printk(KERN_ERR "mac53c94: unable to request memory resources");
	427	return -EBUSY;
	428	}
	429
	430	host = scsi_host_alloc(&mac53c94_template, sizeof(struct fsc_state));
	431	if (host == NULL) {
	432	printk(KERN_ERR "mac53c94: couldn't register host");
cc5d0189	433	rc = -ENOMEM;
1da177e4 LT	434	goto out_release;
	435	}
	436
	437	state = (struct fsc_state *) host->hostdata;
	438	macio_set_drvdata(mdev, state);
	439	state->host = host;
	440	state->pdev = pdev;
	441	state->mdev = mdev;
	442
	443	state->regs = (struct mac53c94_regs __iomem *)
	444	ioremap(macio_resource_start(mdev, 0), 0x1000);
	445	state->intr = macio_irq(mdev, 0);
	446	state->dma = (struct dbdma_regs __iomem *)
	447	ioremap(macio_resource_start(mdev, 1), 0x1000);
	448	state->dmaintr = macio_irq(mdev, 1);
	449	if (state->regs == NULL \|\| state->dma == NULL) {
	450	printk(KERN_ERR "mac53c94: ioremap failed for %s\n",
	451	node->full_name);
	452	goto out_free;
	453	}
	454
40cd3a45	455	clkprop = of_get_property(node, "clock-frequency", &proplen);
1da177e4 LT	456	if (clkprop == NULL \|\| proplen != sizeof(int)) {
	457	printk(KERN_ERR "%s: can't get clock frequency, "
	458	"assuming 25MHz\n", node->full_name);
	459	state->clk_freq = 25000000;
	460	} else
	461	state->clk_freq = (int )clkprop;
	462
	463	/* Space for dma command list: +1 for stop command,
	464	* +1 to allow for aligning.
	465	* XXX FIXME: Use DMA consistent routines
	466	*/
	467	dma_cmd_space = kmalloc((host->sg_tablesize + 2) *
	468	sizeof(struct dbdma_cmd), GFP_KERNEL);
	469	if (dma_cmd_space == 0) {
	470	printk(KERN_ERR "mac53c94: couldn't allocate dma "
	471	"command space for %s\n", node->full_name);
cc5d0189	472	rc = -ENOMEM;
1da177e4 LT	473	goto out_free;
	474	}
	475	state->dma_cmds = (struct dbdma_cmd *)DBDMA_ALIGN(dma_cmd_space);
	476	memset(state->dma_cmds, 0, (host->sg_tablesize + 1)
	477	* sizeof(struct dbdma_cmd));
	478	state->dma_cmd_space = dma_cmd_space;
	479
	480	mac53c94_init(state);
	481
cc5d0189	482	if (request_irq(state->intr, do_mac53c94_interrupt, 0, "53C94",state)) {
1da177e4 LT	483	printk(KERN_ERR "mac53C94: can't get irq %d for %s\n",
	484	state->intr, node->full_name);
	485	goto out_free_dma;
	486	}
	487
cc5d0189 BH	488	rc = scsi_add_host(host, &mdev->ofdev.dev);
	489	if (rc != 0)
	490	goto out_release_irq;
1da177e4	491
cc5d0189	492	scsi_scan_host(host);
1da177e4 LT	493	return 0;
1da177e4 LT	494
cc5d0189 BH	495	out_release_irq:
cc5d0189 BH	496	free_irq(state->intr, state);
1da177e4 LT	497	out_free_dma:
	498	kfree(state->dma_cmd_space);
	499	out_free:
	500	if (state->dma != NULL)
	501	iounmap(state->dma);
	502	if (state->regs != NULL)
	503	iounmap(state->regs);
	504	scsi_host_put(host);
	505	out_release:
	506	macio_release_resources(mdev);
	507
cc5d0189	508	return rc;
1da177e4 LT	509	}
	510
	511	static int mac53c94_remove(struct macio_dev *mdev)
	512	{
	513	struct fsc_state fp = (struct fsc_state )macio_get_drvdata(mdev);
	514	struct Scsi_Host *host = fp->host;
	515
	516	scsi_remove_host(host);
	517
	518	free_irq(fp->intr, fp);
	519
	520	if (fp->regs)
7be7cbf6	521	iounmap(fp->regs);
1da177e4	522	if (fp->dma)
7be7cbf6	523	iounmap(fp->dma);
1da177e4 LT	524	kfree(fp->dma_cmd_space);
	525
	526	scsi_host_put(host);
	527
	528	macio_release_resources(mdev);
	529
	530	return 0;
	531	}
	532
	533
5e655772	534	static struct of_device_id mac53c94_match[] =
1da177e4 LT	535	{
	536	{
	537	.name = "53c94",
1da177e4 LT	538	},
	539	{},
	540	};
5e655772	541	MODULE_DEVICE_TABLE (of, mac53c94_match);
1da177e4 LT	542
	543	static struct macio_driver mac53c94_driver =
	544	{
c2cdf6ab BH	545	.driver = {
	546	.name = "mac53c94",
	547	.owner = THIS_MODULE,
	548	.of_match_table = mac53c94_match,
	549	},
1da177e4 LT	550	.probe = mac53c94_probe,
	551	.remove = mac53c94_remove,
	552	};
	553
	554
	555	static int __init init_mac53c94(void)
	556	{
	557	return macio_register_driver(&mac53c94_driver);
	558	}
	559
	560	static void __exit exit_mac53c94(void)
	561	{
	562	return macio_unregister_driver(&mac53c94_driver);
	563	}
	564
	565	module_init(init_mac53c94);
	566	module_exit(exit_mac53c94);
	567
	568	MODULE_DESCRIPTION("PowerMac 53c94 SCSI driver");
	569	MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
	570	MODULE_LICENSE("GPL");