[linux-2.6-block.git] / drivers / scsi / mac53c94.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * 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 <linux/module.h>
#include <linux/pci.h>
#include <asm/dbdma.h>
#include <asm/io.h>
#include <asm/pgtable.h>
#include <asm/prom.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_lck(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 DEF_SCSI_QCMD(mac53c94_queue)

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;
		dcmds->req_count = cpu_to_le16(dma_len);
		dcmds->command = cpu_to_le16(dma_cmd);
		dcmds->phy_addr = cpu_to_le32(dma_addr);
		dcmds->xfer_status = 0;
		++dcmds;
	}

	dma_cmd += OUTPUT_LAST - OUTPUT_MORE;
	dcmds[-1].command = cpu_to_le16(dma_cmd);
	dcmds->command = cpu_to_le16(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,
	.max_segment_size = 65535,
};

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 %pOF\n", node);
		goto out_free;
	}

	clkprop = of_get_property(node, "clock-frequency", &proplen);
       	if (clkprop == NULL || proplen != sizeof(int)) {
       		printk(KERN_ERR "%pOF: can't get clock frequency, "
       		       "assuming 25MHz\n", node);
       		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_array(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 %pOF\n", node);
		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 %pOF\n",
		       state->intr, node);
		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
09c434b8	1	// SPDX-License-Identifier: GPL-2.0-only
1da177e4 LT	2	/*
	3	* SCSI low-level driver for the 53c94 SCSI bus adaptor found
	4	* on Power Macintosh computers, controlling the external SCSI chain.
	5	* We assume the 53c94 is connected to a DBDMA (descriptor-based DMA)
	6	* controller.
	7	*
	8	* Paul Mackerras, August 1996.
	9	* Copyright (C) 1996 Paul Mackerras.
	10	*/
	11	#include <linux/kernel.h>
	12	#include <linux/delay.h>
	13	#include <linux/types.h>
	14	#include <linux/string.h>
	15	#include <linux/slab.h>
	16	#include <linux/blkdev.h>
	17	#include <linux/proc_fs.h>
	18	#include <linux/stat.h>
	19	#include <linux/spinlock.h>
	20	#include <linux/interrupt.h>
acf3368f	21	#include <linux/module.h>
952bbcb0	22	#include <linux/pci.h>
1da177e4 LT	23	#include <asm/dbdma.h>
	24	#include <asm/io.h>
	25	#include <asm/pgtable.h>
	26	#include <asm/prom.h>
1da177e4 LT	27	#include <asm/macio.h>
	28
	29	#include <scsi/scsi.h>
	30	#include <scsi/scsi_cmnd.h>
	31	#include <scsi/scsi_device.h>
	32	#include <scsi/scsi_host.h>
	33
	34	#include "mac53c94.h"
	35
	36	enum fsc_phase {
	37	idle,
	38	selecting,
	39	dataing,
	40	completing,
	41	busfreeing,
	42	};
	43
	44	struct fsc_state {
	45	struct mac53c94_regs __iomem *regs;
	46	int intr;
	47	struct dbdma_regs __iomem *dma;
	48	int dmaintr;
	49	int clk_freq;
	50	struct Scsi_Host *host;
	51	struct scsi_cmnd *request_q;
	52	struct scsi_cmnd *request_qtail;
	53	struct scsi_cmnd current_req; / req we're currently working on */
	54	enum fsc_phase phase; /* what we're currently trying to do */
	55	struct dbdma_cmd dma_cmds; / space for dbdma commands, aligned */
	56	void *dma_cmd_space;
	57	struct pci_dev *pdev;
	58	dma_addr_t dma_addr;
	59	struct macio_dev *mdev;
	60	};
	61
	62	static void mac53c94_init(struct fsc_state *);
	63	static void mac53c94_start(struct fsc_state *);
7d12e780 DH	64	static void mac53c94_interrupt(int, void *);
7d12e780 DH	65	static irqreturn_t do_mac53c94_interrupt(int, void *);
1da177e4 LT	66	static void cmd_done(struct fsc_state *, int result);
	67	static void set_dma_cmds(struct fsc_state , struct scsi_cmnd );
	68
	69
f281233d	70	static int mac53c94_queue_lck(struct scsi_cmnd cmd, void (done)(struct scsi_cmnd *))
1da177e4 LT	71	{
	72	struct fsc_state *state;
	73
	74	#if 0
	75	if (cmd->sc_data_direction == DMA_TO_DEVICE) {
	76	int i;
	77	printk(KERN_DEBUG "mac53c94_queue %p: command is", cmd);
	78	for (i = 0; i < cmd->cmd_len; ++i)
ad361c98 JP	79	printk(KERN_CONT " %.2x", cmd->cmnd[i]);
	80	printk(KERN_CONT "\n");
	81	printk(KERN_DEBUG "use_sg=%d request_bufflen=%d request_buffer=%p\n",
646158c2	82	scsi_sg_count(cmd), scsi_bufflen(cmd), scsi_sglist(cmd));
1da177e4 LT	83	}
	84	#endif
	85
	86	cmd->scsi_done = done;
	87	cmd->host_scribble = NULL;
	88
	89	state = (struct fsc_state *) cmd->device->host->hostdata;
	90
	91	if (state->request_q == NULL)
	92	state->request_q = cmd;
	93	else
	94	state->request_qtail->host_scribble = (void *) cmd;
	95	state->request_qtail = cmd;
	96
	97	if (state->phase == idle)
	98	mac53c94_start(state);
	99
	100	return 0;
	101	}
	102
f281233d JG	103	static DEF_SCSI_QCMD(mac53c94_queue)
f281233d JG	104
1da177e4 LT	105	static int mac53c94_host_reset(struct scsi_cmnd *cmd)
	106	{
	107	struct fsc_state state = (struct fsc_state ) cmd->device->host->hostdata;
	108	struct mac53c94_regs __iomem *regs = state->regs;
	109	struct dbdma_regs __iomem *dma = state->dma;
df0ae249 JG	110	unsigned long flags;
	111
	112	spin_lock_irqsave(cmd->device->host->host_lock, flags);
1da177e4 LT	113
	114	writel((RUN\|PAUSE\|FLUSH\|WAKE) << 16, &dma->control);
	115	writeb(CMD_SCSI_RESET, &regs->command); /* assert RST */
	116	udelay(100); /* leave it on for a while (>= 25us) */
	117	writeb(CMD_RESET, &regs->command);
	118	udelay(20);
	119	mac53c94_init(state);
	120	writeb(CMD_NOP, &regs->command);
df0ae249 JG	121
df0ae249 JG	122	spin_unlock_irqrestore(cmd->device->host->host_lock, flags);
1da177e4 LT	123	return SUCCESS;
	124	}
	125
	126	static void mac53c94_init(struct fsc_state *state)
	127	{
	128	struct mac53c94_regs __iomem *regs = state->regs;
	129	struct dbdma_regs __iomem *dma = state->dma;
	130	int x;
	131
	132	writeb(state->host->this_id \| CF1_PAR_ENABLE, &regs->config1);
	133	writeb(TIMO_VAL(250), &regs->sel_timeout); /* 250ms */
	134	writeb(CLKF_VAL(state->clk_freq), &regs->clk_factor);
	135	writeb(CF2_FEATURE_EN, &regs->config2);
	136	writeb(0, &regs->config3);
	137	writeb(0, &regs->sync_period);
	138	writeb(0, &regs->sync_offset);
	139	x = readb(&regs->interrupt);
	140	writel((RUN\|PAUSE\|FLUSH\|WAKE) << 16, &dma->control);
	141	}
	142
	143	/*
	144	* Start the next command for a 53C94.
	145	* Should be called with interrupts disabled.
	146	*/
	147	static void mac53c94_start(struct fsc_state *state)
	148	{
	149	struct scsi_cmnd *cmd;
	150	struct mac53c94_regs __iomem *regs = state->regs;
	151	int i;
	152
	153	if (state->phase != idle \|\| state->current_req != NULL)
	154	panic("inappropriate mac53c94_start (state=%p)", state);
	155	if (state->request_q == NULL)
	156	return;
	157	state->current_req = cmd = state->request_q;
	158	state->request_q = (struct scsi_cmnd *) cmd->host_scribble;
	159
	160	/* Off we go */
	161	writeb(0, &regs->count_lo);
	162	writeb(0, &regs->count_mid);
	163	writeb(0, &regs->count_hi);
	164	writeb(CMD_NOP + CMD_DMA_MODE, &regs->command);
	165	udelay(1);
	166	writeb(CMD_FLUSH, &regs->command);
	167	udelay(1);
	168	writeb(cmd->device->id, &regs->dest_id);
	169	writeb(0, &regs->sync_period);
	170	writeb(0, &regs->sync_offset);
	171
	172	/* load the command into the FIFO */
	173	for (i = 0; i < cmd->cmd_len; ++i)
	174	writeb(cmd->cmnd[i], &regs->fifo);
	175
	176	/* do select without ATN XXX */
	177	writeb(CMD_SELECT, &regs->command);
	178	state->phase = selecting;
	179
646158c2	180	set_dma_cmds(state, cmd);
1da177e4 LT	181	}
1da177e4 LT	182
7d12e780	183	static irqreturn_t do_mac53c94_interrupt(int irq, void *dev_id)
1da177e4 LT	184	{
	185	unsigned long flags;
	186	struct Scsi_Host dev = ((struct fsc_state ) dev_id)->current_req->device->host;
	187
	188	spin_lock_irqsave(dev->host_lock, flags);
7d12e780	189	mac53c94_interrupt(irq, dev_id);
1da177e4 LT	190	spin_unlock_irqrestore(dev->host_lock, flags);
	191	return IRQ_HANDLED;
	192	}
	193
7d12e780	194	static void mac53c94_interrupt(int irq, void *dev_id)
1da177e4 LT	195	{
	196	struct fsc_state state = (struct fsc_state ) dev_id;
	197	struct mac53c94_regs __iomem *regs = state->regs;
	198	struct dbdma_regs __iomem *dma = state->dma;
	199	struct scsi_cmnd *cmd = state->current_req;
	200	int nb, stat, seq, intr;
	201	static int mac53c94_errors;
	202
	203	/*
	204	* Apparently, reading the interrupt register unlatches
	205	* the status and sequence step registers.
	206	*/
	207	seq = readb(&regs->seqstep);
	208	stat = readb(&regs->status);
	209	intr = readb(&regs->interrupt);
	210
	211	#if 0
	212	printk(KERN_DEBUG "mac53c94_intr, intr=%x stat=%x seq=%x phase=%d\n",
	213	intr, stat, seq, state->phase);
	214	#endif
	215
	216	if (intr & INTR_RESET) {
	217	/* SCSI bus was reset */
	218	printk(KERN_INFO "external SCSI bus reset detected\n");
	219	writeb(CMD_NOP, &regs->command);
	220	writel(RUN << 16, &dma->control); /* stop dma */
	221	cmd_done(state, DID_RESET << 16);
	222	return;
	223	}
	224	if (intr & INTR_ILL_CMD) {
	225	printk(KERN_ERR "53c94: invalid cmd, intr=%x stat=%x seq=%x phase=%d\n",
	226	intr, stat, seq, state->phase);
	227	cmd_done(state, DID_ERROR << 16);
	228	return;
	229	}
	230	if (stat & STAT_ERROR) {
	231	#if 0
	232	/* XXX these seem to be harmless? */
	233	printk("53c94: bad error, intr=%x stat=%x seq=%x phase=%d\n",
	234	intr, stat, seq, state->phase);
	235	#endif
	236	++mac53c94_errors;
	237	writeb(CMD_NOP + CMD_DMA_MODE, &regs->command);
	238	}
	239	if (cmd == 0) {
	240	printk(KERN_DEBUG "53c94: interrupt with no command active?\n");
	241	return;
	242	}
	243	if (stat & STAT_PARITY) {
	244	printk(KERN_ERR "mac53c94: parity error\n");
	245	cmd_done(state, DID_PARITY << 16);
	246	return;
	247	}
	248	switch (state->phase) {
	249	case selecting:
	250	if (intr & INTR_DISCONNECT) {
	251	/* selection timed out */
	252	cmd_done(state, DID_BAD_TARGET << 16);
	253	return;
	254	}
	255	if (intr != INTR_BUS_SERV + INTR_DONE) {
	256	printk(KERN_DEBUG "got intr %x during selection\n", intr);
	257	cmd_done(state, DID_ERROR << 16);
	258	return;
259	}
260	if ((seq & SS_MASK) != SS_DONE) {
261	printk(KERN_DEBUG "seq step %x after command\n", seq);
262	cmd_done(state, DID_ERROR << 16);
263	return;
264	}
265	writeb(CMD_NOP, &regs->command);
266	/* set DMA controller going if any data to transfer */
267	if ((stat & (STAT_MSG\|STAT_CD)) == 0
646158c2	268	&& (scsi_sg_count(cmd) > 0 \|\| scsi_bufflen(cmd))) {
1da177e4 LT	269	nb = cmd->SCp.this_residual;
	270	if (nb > 0xfff0)
	271	nb = 0xfff0;
	272	cmd->SCp.this_residual -= nb;
	273	writeb(nb, &regs->count_lo);
	274	writeb(nb >> 8, &regs->count_mid);
	275	writeb(CMD_DMA_MODE + CMD_NOP, &regs->command);
	276	writel(virt_to_phys(state->dma_cmds), &dma->cmdptr);
	277	writel((RUN << 16) \| RUN, &dma->control);
	278	writeb(CMD_DMA_MODE + CMD_XFER_DATA, &regs->command);
	279	state->phase = dataing;
	280	break;
	281	} else if ((stat & STAT_PHASE) == STAT_CD + STAT_IO) {
	282	/* up to status phase already */
	283	writeb(CMD_I_COMPLETE, &regs->command);
	284	state->phase = completing;
	285	} else {
	286	printk(KERN_DEBUG "in unexpected phase %x after cmd\n",
	287	stat & STAT_PHASE);
	288	cmd_done(state, DID_ERROR << 16);
	289	return;
	290	}
	291	break;
	292
	293	case dataing:
	294	if (intr != INTR_BUS_SERV) {
	295	printk(KERN_DEBUG "got intr %x before status\n", intr);
	296	cmd_done(state, DID_ERROR << 16);
	297	return;
	298	}
	299	if (cmd->SCp.this_residual != 0
	300	&& (stat & (STAT_MSG\|STAT_CD)) == 0) {
	301	/* Set up the count regs to transfer more */
	302	nb = cmd->SCp.this_residual;
	303	if (nb > 0xfff0)
	304	nb = 0xfff0;
	305	cmd->SCp.this_residual -= nb;
	306	writeb(nb, &regs->count_lo);
	307	writeb(nb >> 8, &regs->count_mid);
	308	writeb(CMD_DMA_MODE + CMD_NOP, &regs->command);
	309	writeb(CMD_DMA_MODE + CMD_XFER_DATA, &regs->command);
	310	break;
	311	}
	312	if ((stat & STAT_PHASE) != STAT_CD + STAT_IO) {
	313	printk(KERN_DEBUG "intr %x before data xfer complete\n", intr);
	314	}
	315	writel(RUN << 16, &dma->control); /* stop dma */
646158c2	316	scsi_dma_unmap(cmd);
1da177e4 LT	317	/* should check dma status */
	318	writeb(CMD_I_COMPLETE, &regs->command);
	319	state->phase = completing;
	320	break;
	321	case completing:
	322	if (intr != INTR_DONE) {
	323	printk(KERN_DEBUG "got intr %x on completion\n", intr);
	324	cmd_done(state, DID_ERROR << 16);
	325	return;
	326	}
	327	cmd->SCp.Status = readb(&regs->fifo);
	328	cmd->SCp.Message = readb(&regs->fifo);
	329	cmd->result = CMD_ACCEPT_MSG;
	330	writeb(CMD_ACCEPT_MSG, &regs->command);
	331	state->phase = busfreeing;
	332	break;
	333	case busfreeing:
	334	if (intr != INTR_DISCONNECT) {
	335	printk(KERN_DEBUG "got intr %x when expected disconnect\n", intr);
	336	}
	337	cmd_done(state, (DID_OK << 16) + (cmd->SCp.Message << 8)
	338	+ cmd->SCp.Status);
	339	break;
	340	default:
	341	printk(KERN_DEBUG "don't know about phase %d\n", state->phase);
	342	}
	343	}
	344
	345	static void cmd_done(struct fsc_state *state, int result)
	346	{
	347	struct scsi_cmnd *cmd;
	348
	349	cmd = state->current_req;
	350	if (cmd != 0) {
	351	cmd->result = result;
	352	(*cmd->scsi_done)(cmd);
	353	state->current_req = NULL;
	354	}
	355	state->phase = idle;
	356	mac53c94_start(state);
	357	}
	358
	359	/*
	360	* Set up DMA commands for transferring data.
	361	*/
	362	static void set_dma_cmds(struct fsc_state state, struct scsi_cmnd cmd)
	363	{
646158c2	364	int i, dma_cmd, total, nseg;
1da177e4 LT	365	struct scatterlist *scl;
	366	struct dbdma_cmd *dcmds;
	367	dma_addr_t dma_addr;
	368	u32 dma_len;
	369
646158c2 FT	370	nseg = scsi_dma_map(cmd);
	371	BUG_ON(nseg < 0);
	372	if (!nseg)
	373	return;
	374
1da177e4 LT	375	dma_cmd = cmd->sc_data_direction == DMA_TO_DEVICE ?
	376	OUTPUT_MORE : INPUT_MORE;
	377	dcmds = state->dma_cmds;
646158c2 FT	378	total = 0;
	379
	380	scsi_for_each_sg(cmd, scl, nseg, i) {
	381	dma_addr = sg_dma_address(scl);
	382	dma_len = sg_dma_len(scl);
	383	if (dma_len > 0xffff)
	384	panic("mac53c94: scatterlist element >= 64k");
	385	total += dma_len;
f5718726 DG	386	dcmds->req_count = cpu_to_le16(dma_len);
	387	dcmds->command = cpu_to_le16(dma_cmd);
	388	dcmds->phy_addr = cpu_to_le32(dma_addr);
1da177e4 LT	389	dcmds->xfer_status = 0;
	390	++dcmds;
	391	}
646158c2	392
1da177e4	393	dma_cmd += OUTPUT_LAST - OUTPUT_MORE;
f5718726 DG	394	dcmds[-1].command = cpu_to_le16(dma_cmd);
f5718726 DG	395	dcmds->command = cpu_to_le16(DBDMA_STOP);
1da177e4 LT	396	cmd->SCp.this_residual = total;
	397	}
	398
	399	static struct scsi_host_template mac53c94_template = {
	400	.proc_name = "53c94",
	401	.name = "53C94",
	402	.queuecommand = mac53c94_queue,
1da177e4 LT	403	.eh_host_reset_handler = mac53c94_host_reset,
	404	.can_queue = 1,
	405	.this_id = 7,
	406	.sg_tablesize = SG_ALL,
1c3726ad	407	.max_segment_size = 65535,
1da177e4 LT	408	};
1da177e4 LT	409
5e655772	410	static int mac53c94_probe(struct macio_dev mdev, const struct of_device_id match)
1da177e4 LT	411	{
	412	struct device_node *node = macio_get_of_node(mdev);
	413	struct pci_dev *pdev = macio_get_pci_dev(mdev);
	414	struct fsc_state *state;
	415	struct Scsi_Host *host;
	416	void *dma_cmd_space;
294ef16a	417	const unsigned char *clkprop;
cc5d0189	418	int proplen, rc = -ENODEV;
1da177e4 LT	419
1da177e4 LT	420	if (macio_resource_count(mdev) != 2 \|\| macio_irq_count(mdev) != 2) {
cc5d0189 BH	421	printk(KERN_ERR "mac53c94: expected 2 addrs and intrs"
	422	" (got %d/%d)\n",
	423	macio_resource_count(mdev), macio_irq_count(mdev));
1da177e4 LT	424	return -ENODEV;
	425	}
	426
	427	if (macio_request_resources(mdev, "mac53c94") != 0) {
	428	printk(KERN_ERR "mac53c94: unable to request memory resources");
	429	return -EBUSY;
	430	}
	431
	432	host = scsi_host_alloc(&mac53c94_template, sizeof(struct fsc_state));
	433	if (host == NULL) {
	434	printk(KERN_ERR "mac53c94: couldn't register host");
cc5d0189	435	rc = -ENOMEM;
1da177e4 LT	436	goto out_release;
	437	}
	438
	439	state = (struct fsc_state *) host->hostdata;
	440	macio_set_drvdata(mdev, state);
	441	state->host = host;
	442	state->pdev = pdev;
	443	state->mdev = mdev;
	444
	445	state->regs = (struct mac53c94_regs __iomem *)
	446	ioremap(macio_resource_start(mdev, 0), 0x1000);
	447	state->intr = macio_irq(mdev, 0);
	448	state->dma = (struct dbdma_regs __iomem *)
	449	ioremap(macio_resource_start(mdev, 1), 0x1000);
	450	state->dmaintr = macio_irq(mdev, 1);
	451	if (state->regs == NULL \|\| state->dma == NULL) {
22fe5670	452	printk(KERN_ERR "mac53c94: ioremap failed for %pOF\n", node);
1da177e4 LT	453	goto out_free;
	454	}
	455
40cd3a45	456	clkprop = of_get_property(node, "clock-frequency", &proplen);
1da177e4	457	if (clkprop == NULL \|\| proplen != sizeof(int)) {
22fe5670 RH	458	printk(KERN_ERR "%pOF: can't get clock frequency, "
22fe5670 RH	459	"assuming 25MHz\n", node);
1da177e4 LT	460	state->clk_freq = 25000000;
	461	} else
	462	state->clk_freq = (int )clkprop;
	463
	464	/* Space for dma command list: +1 for stop command,
	465	* +1 to allow for aligning.
	466	* XXX FIXME: Use DMA consistent routines
	467	*/
6da2ec56 KC	468	dma_cmd_space = kmalloc_array(host->sg_tablesize + 2,
	469	sizeof(struct dbdma_cmd),
	470	GFP_KERNEL);
1da177e4 LT	471	if (dma_cmd_space == 0) {
1da177e4 LT	472	printk(KERN_ERR "mac53c94: couldn't allocate dma "
22fe5670	473	"command space for %pOF\n", node);
cc5d0189	474	rc = -ENOMEM;
1da177e4 LT	475	goto out_free;
	476	}
	477	state->dma_cmds = (struct dbdma_cmd *)DBDMA_ALIGN(dma_cmd_space);
	478	memset(state->dma_cmds, 0, (host->sg_tablesize + 1)
	479	* sizeof(struct dbdma_cmd));
	480	state->dma_cmd_space = dma_cmd_space;
	481
	482	mac53c94_init(state);
	483
cc5d0189	484	if (request_irq(state->intr, do_mac53c94_interrupt, 0, "53C94",state)) {
22fe5670 RH	485	printk(KERN_ERR "mac53C94: can't get irq %d for %pOF\n",
22fe5670 RH	486	state->intr, node);
1da177e4 LT	487	goto out_free_dma;
	488	}
	489
cc5d0189 BH	490	rc = scsi_add_host(host, &mdev->ofdev.dev);
	491	if (rc != 0)
	492	goto out_release_irq;
1da177e4	493
cc5d0189	494	scsi_scan_host(host);
1da177e4 LT	495	return 0;
1da177e4 LT	496
cc5d0189 BH	497	out_release_irq:
cc5d0189 BH	498	free_irq(state->intr, state);
1da177e4 LT	499	out_free_dma:
	500	kfree(state->dma_cmd_space);
	501	out_free:
	502	if (state->dma != NULL)
	503	iounmap(state->dma);
	504	if (state->regs != NULL)
	505	iounmap(state->regs);
	506	scsi_host_put(host);
	507	out_release:
	508	macio_release_resources(mdev);
	509
cc5d0189	510	return rc;
1da177e4 LT	511	}
	512
	513	static int mac53c94_remove(struct macio_dev *mdev)
	514	{
	515	struct fsc_state fp = (struct fsc_state )macio_get_drvdata(mdev);
	516	struct Scsi_Host *host = fp->host;
	517
	518	scsi_remove_host(host);
	519
	520	free_irq(fp->intr, fp);
	521
	522	if (fp->regs)
7be7cbf6	523	iounmap(fp->regs);
1da177e4	524	if (fp->dma)
7be7cbf6	525	iounmap(fp->dma);
1da177e4 LT	526	kfree(fp->dma_cmd_space);
	527
	528	scsi_host_put(host);
	529
	530	macio_release_resources(mdev);
	531
	532	return 0;
	533	}
	534
	535
5e655772	536	static struct of_device_id mac53c94_match[] =
1da177e4 LT	537	{
	538	{
	539	.name = "53c94",
1da177e4 LT	540	},
	541	{},
	542	};
5e655772	543	MODULE_DEVICE_TABLE (of, mac53c94_match);
1da177e4 LT	544
	545	static struct macio_driver mac53c94_driver =
	546	{
c2cdf6ab BH	547	.driver = {
	548	.name = "mac53c94",
	549	.owner = THIS_MODULE,
	550	.of_match_table = mac53c94_match,
	551	},
1da177e4 LT	552	.probe = mac53c94_probe,
	553	.remove = mac53c94_remove,
	554	};
	555
	556
	557	static int __init init_mac53c94(void)
	558	{
	559	return macio_register_driver(&mac53c94_driver);
	560	}
	561
	562	static void __exit exit_mac53c94(void)
	563	{
	564	return macio_unregister_driver(&mac53c94_driver);
	565	}
	566
	567	module_init(init_mac53c94);
	568	module_exit(exit_mac53c94);
	569
	570	MODULE_DESCRIPTION("PowerMac 53c94 SCSI driver");
	571	MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
	572	MODULE_LICENSE("GPL");