icside.c

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/*
 * linux/drivers/ide/icside.c
 *
 * Copyright (c) 1996,1997 Russell King.
 *
 * Changelog:
 *  08-Jun-1996	RMK	Created
 *  12-Sep-1997	RMK	Added interrupt enable/disable
 *  17-Apr-1999	RMK	Added support for V6 EASI
 *  22-May-1999	RMK	Added support for V6 DMA
 */

#include <linux/config.h>
#include <linux/string.h>
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/slab.h>
#include <linux/blkdev.h>
#include <linux/errno.h>
#include <linux/hdreg.h>
#include <linux/ide.h>
#include <linux/pci.h>
#include <linux/init.h>

#include <asm/dma.h>
#include <asm/ecard.h>
#include <asm/io.h>

extern char *ide_xfer_verbose (byte xfer_rate);
extern char *ide_dmafunc_verbose(ide_dma_action_t dmafunc);

/*
 * Maximum number of interfaces per card
 */
#define MAX_IFS	2

#define ICS_IDENT_OFFSET		0x8a0

#define ICS_ARCIN_V5_INTRSTAT		0x000
#define ICS_ARCIN_V5_INTROFFSET		0x001
#define ICS_ARCIN_V5_IDEOFFSET		0xa00
#define ICS_ARCIN_V5_IDEALTOFFSET	0xae0
#define ICS_ARCIN_V5_IDESTEPPING	4

#define ICS_ARCIN_V6_IDEOFFSET_1	0x800
#define ICS_ARCIN_V6_INTROFFSET_1	0x880
#define ICS_ARCIN_V6_INTRSTAT_1		0x8a4
#define ICS_ARCIN_V6_IDEALTOFFSET_1	0x8e0
#define ICS_ARCIN_V6_IDEOFFSET_2	0xc00
#define ICS_ARCIN_V6_INTROFFSET_2	0xc80
#define ICS_ARCIN_V6_INTRSTAT_2		0xca4
#define ICS_ARCIN_V6_IDEALTOFFSET_2	0xce0
#define ICS_ARCIN_V6_IDESTEPPING	4

struct cardinfo {
	unsigned int dataoffset;
	unsigned int ctrloffset;
	unsigned int stepping;
};

static struct cardinfo icside_cardinfo_v5 = {
	ICS_ARCIN_V5_IDEOFFSET,
	ICS_ARCIN_V5_IDEALTOFFSET,
	ICS_ARCIN_V5_IDESTEPPING
};

static struct cardinfo icside_cardinfo_v6_1 = {
	ICS_ARCIN_V6_IDEOFFSET_1,
	ICS_ARCIN_V6_IDEALTOFFSET_1,
	ICS_ARCIN_V6_IDESTEPPING
};

static struct cardinfo icside_cardinfo_v6_2 = {
	ICS_ARCIN_V6_IDEOFFSET_2,
	ICS_ARCIN_V6_IDEALTOFFSET_2,
	ICS_ARCIN_V6_IDESTEPPING
};

struct icside_state {
	unsigned int channel;
	unsigned int enabled;
	unsigned int irq_port;
};

static const card_ids icside_cids[] = {
	{ MANU_ICS,  PROD_ICS_IDE  },
	{ MANU_ICS2, PROD_ICS2_IDE },
	{ 0xffff, 0xffff }
};

typedef enum {
	ics_if_unknown,
	ics_if_arcin_v5,
	ics_if_arcin_v6
} iftype_t;

/* ---------------- Version 5 PCB Support Functions --------------------- */
/* Prototype: icside_irqenable_arcin_v5 (struct expansion_card *ec, int irqnr)
 * Purpose  : enable interrupts from card
 */
static void icside_irqenable_arcin_v5 (struct expansion_card *ec, int irqnr)
{
	unsigned int memc_port = (unsigned int)ec->irq_data;
	outb (0, memc_port + ICS_ARCIN_V5_INTROFFSET);
}

/* Prototype: icside_irqdisable_arcin_v5 (struct expansion_card *ec, int irqnr)
 * Purpose  : disable interrupts from card
 */
static void icside_irqdisable_arcin_v5 (struct expansion_card *ec, int irqnr)
{
	unsigned int memc_port = (unsigned int)ec->irq_data;
	inb (memc_port + ICS_ARCIN_V5_INTROFFSET);
}

static const expansioncard_ops_t icside_ops_arcin_v5 = {
	icside_irqenable_arcin_v5,
	icside_irqdisable_arcin_v5,
	NULL,
	NULL,
	NULL,
	NULL
};


/* ---------------- Version 6 PCB Support Functions --------------------- */
/* Prototype: icside_irqenable_arcin_v6 (struct expansion_card *ec, int irqnr)
 * Purpose  : enable interrupts from card
 */
static void icside_irqenable_arcin_v6 (struct expansion_card *ec, int irqnr)
{
	struct icside_state *state = ec->irq_data;
	unsigned int base = state->irq_port;

	state->enabled = 1;

	switch (state->channel) {
	case 0:
		outb(0, base + ICS_ARCIN_V6_INTROFFSET_1);
		inb(base + ICS_ARCIN_V6_INTROFFSET_2);
		break;
	case 1:
		outb(0, base + ICS_ARCIN_V6_INTROFFSET_2);
		inb(base + ICS_ARCIN_V6_INTROFFSET_1);
		break;
	}
}

/* Prototype: icside_irqdisable_arcin_v6 (struct expansion_card *ec, int irqnr)
 * Purpose  : disable interrupts from card
 */
static void icside_irqdisable_arcin_v6 (struct expansion_card *ec, int irqnr)
{
	struct icside_state *state = ec->irq_data;

	state->enabled = 0;

	inb (state->irq_port + ICS_ARCIN_V6_INTROFFSET_1);
	inb (state->irq_port + ICS_ARCIN_V6_INTROFFSET_2);
}

/* Prototype: icside_irqprobe(struct expansion_card *ec)
 * Purpose  : detect an active interrupt from card
 */
static int icside_irqpending_arcin_v6(struct expansion_card *ec)
{
	struct icside_state *state = ec->irq_data;

	return inb(state->irq_port + ICS_ARCIN_V6_INTRSTAT_1) & 1 ||
	       inb(state->irq_port + ICS_ARCIN_V6_INTRSTAT_2) & 1;
}

static const expansioncard_ops_t icside_ops_arcin_v6 = {
	icside_irqenable_arcin_v6,
	icside_irqdisable_arcin_v6,
	icside_irqpending_arcin_v6,
	NULL,
	NULL,
	NULL
};

/* Prototype: icside_identifyif (struct expansion_card *ec)
 * Purpose  : identify IDE interface type
 * Notes    : checks the description string
 */
static iftype_t __init icside_identifyif (struct expansion_card *ec)
{
	unsigned int addr;
	iftype_t iftype;
	int id = 0;

	iftype = ics_if_unknown;

	addr = ecard_address (ec, ECARD_IOC, ECARD_FAST) + ICS_IDENT_OFFSET;

	id = inb (addr) & 1;
	id |= (inb (addr + 1) & 1) << 1;
	id |= (inb (addr + 2) & 1) << 2;
	id |= (inb (addr + 3) & 1) << 3;

	switch (id) {
	case 0: /* A3IN */
		printk("icside: A3IN unsupported\n");
		break;

	case 1: /* A3USER */
		printk("icside: A3USER unsupported\n");
		break;

	case 3:	/* ARCIN V6 */
		printk(KERN_DEBUG "icside: detected ARCIN V6 in slot %d\n", ec->slot_no);
		iftype = ics_if_arcin_v6;
		break;

	case 15:/* ARCIN V5 (no id) */
		printk(KERN_DEBUG "icside: detected ARCIN V5 in slot %d\n", ec->slot_no);
		iftype = ics_if_arcin_v5;
		break;

	default:/* we don't know - complain very loudly */
		printk("icside: ***********************************\n");
		printk("icside: *** UNKNOWN ICS INTERFACE id=%d ***\n", id);
		printk("icside: ***********************************\n");
		printk("icside: please report this to [e-mail]\n");
		printk("icside: defaulting to ARCIN V5\n");
		iftype = ics_if_arcin_v5;
		break;
	}

	return iftype;
}

/*
 * Handle routing of interrupts.  This is called before
 * we write a command to the drive.
 */
static void icside_maskproc(ide_drive_t *drive, int mask)
{
	ide_hwif_t *hwif = HWIF(drive);
	struct icside_state *state = hwif->hw.priv;
	unsigned long flags;

	local_irq_save(flags);

	state->channel = hwif->channel;

	if (state->enabled && !mask) {
		switch (hwif->channel) {
		case 0:
			outb(0, state->irq_port + ICS_ARCIN_V6_INTROFFSET_1);
			inb(state->irq_port + ICS_ARCIN_V6_INTROFFSET_2);
			break;
		case 1:
			outb(0, state->irq_port + ICS_ARCIN_V6_INTROFFSET_2);
			inb(state->irq_port + ICS_ARCIN_V6_INTROFFSET_1);
			break;
		}
	} else {
		inb(state->irq_port + ICS_ARCIN_V6_INTROFFSET_2);
		inb(state->irq_port + ICS_ARCIN_V6_INTROFFSET_1);
	}

	local_irq_restore(flags);
}

#ifdef CONFIG_BLK_DEV_IDEDMA_ICS

static int icside_dmaproc(ide_dma_action_t func, ide_drive_t *drive);

/*
 * SG-DMA support.
 *
 * Similar to the BM-DMA, but we use the RiscPCs IOMD DMA controllers.
 * There is only one DMA controller per card, which means that only
 * one drive can be accessed at one time.  NOTE! We do not enforce that
 * here, but we rely on the main IDE driver spotting that both
 * interfaces use the same IRQ, which should guarantee this.
 */
#define NR_ENTRIES 256
#define TABLE_SIZE (NR_ENTRIES * 8)

static int icside_build_dmatable(ide_drive_t *drive, int dma_mode)
{
	ide_hwif_t *hwif = HWIF(drive);
	struct request *rq = HWGROUP(drive)->rq;
	struct buffer_head *bh;
	struct scatterlist *sg = hwif->sg_table;
	int nents = 0;

	bh = rq->bh;
	do {
		char *virt_addr;

		memset(sg, 0, sizeof(*sg));
		sg->address = virt_addr = bh->b_data;

		do {
			virt_addr += bh->b_size;

			bh = bh->b_reqnext;
			if (bh == NULL)
				break;

		} while (virt_addr == bh->b_data);

		sg->length = virt_addr - (char *)sg->address;
		sg++;
		nents++;
	} while (bh != NULL);

	if (dma_mode == DMA_MODE_READ)
		hwif->sg_dma_direction = PCI_DMA_FROMDEVICE;
	else
		hwif->sg_dma_direction = PCI_DMA_TODEVICE;

	hwif->sg_nents = pci_map_sg(NULL, hwif->sg_table, nents,
				    hwif->sg_dma_direction);

	return hwif->sg_nents;
}

/* Teardown mappings after DMA has completed.  */
static inline void icside_destroy_dmatable(ide_hwif_t *hwif)
{
	pci_unmap_sg(NULL, hwif->sg_table, hwif->sg_nents,
		     hwif->sg_dma_direction);
}

/*
 * Configure the IOMD to give the appropriate timings for the transfer
 * mode being requested.  We take the advice of the ATA standards, and
 * calculate the cycle time based on the transfer mode, and the EIDE
 * MW DMA specs that the drive provides in the IDENTIFY command.
 *
 * We have the following IOMD DMA modes to choose from:
 *
 *	Type	Active		Recovery	Cycle
 *	A	250 (250)	312 (550)	562 (800)
 *	B	187		250		437
 *	C	125 (125)	125 (375)	250 (500)
 *	D	62		125		187
 *
 * (figures in brackets are actual measured timings)
 *
 * However, we also need to take care of the read/write active and
 * recovery timings:
 *
 *			Read	Write
 *  	Mode	Active	-- Recovery --	Cycle	IOMD type
 *	MW0	215	50	215	480	A
 *	MW1	80	50	50	150	C
 *	MW2	70	25	25	120	C
 */
static int icside_speedproc(ide_drive_t *drive, byte xfer_mode)
{
	int func = ide_dma_off;
	int cycle_time = 0, use_dma_info = 0;

	/*
	 * Limit the transfer speed to MW_DMA_2.
	 */
	if (xfer_mode > XFER_MW_DMA_2)
		xfer_mode = XFER_MW_DMA_2;

	switch (xfer_mode) {
	case XFER_MW_DMA_2:
		cycle_time = 250;
		use_dma_info = 1;
		break;
	case XFER_MW_DMA_1:
		cycle_time = 250;
		use_dma_info = 1;
		break;
	case XFER_MW_DMA_0:
		cycle_time = 480;
		break;

	case XFER_SW_DMA_2:
	case XFER_SW_DMA_1:
	case XFER_SW_DMA_0:
		cycle_time = 480;
		break;

	default:
		func = ide_dma_off;
		break;
	}

	/*
	 * If we're going to be doing MW_DMA_1 or MW_DMA_2, we should
	 * take care to note the values in the ID...
	 */
	if (use_dma_info && drive->id->eide_dma_time > cycle_time)
		cycle_time = drive->id->eide_dma_time;

	drive->drive_data = cycle_time;

	if (cycle_time && ide_config_drive_speed(drive, xfer_mode) == 0)
		func = ide_dma_on;
	else
		drive->drive_data = 480;

	if (!drive->init_speed)
		drive->init_speed = xfer_mode;
	else if (cycle_time)
		printk("%s: %s selected (peak %dMB/s)\n", drive->name,
			ide_xfer_verbose(xfer_mode), 2000 / drive->drive_data);

	drive->current_speed = xfer_mode;

	return func;
}

/*
 * dma_intr() is the handler for disk read/write DMA interrupts
 */
static ide_startstop_t icside_dmaintr(ide_drive_t *drive)
{
	byte stat, dma_stat;

	dma_stat = icside_dmaproc(ide_dma_end, drive);

	/*
	 * Verify the drive status
	 */
	stat = GET_STAT();
	if (OK_STAT(stat,DRIVE_READY,drive->bad_wstat|DRQ_STAT)) {
		if (!dma_stat) {
			struct request *rq = HWGROUP(drive)->rq;
			int i;

			for (i = rq->nr_sectors; i > 0;) {
				i -= rq->current_nr_sectors;
				ide_end_request(1, HWGROUP(drive));
			}

			return ide_stopped;
		}
		printk("%s: dma_intr: bad DMA status (dma_stat=%x)\n", 
		       drive->name, dma_stat);
	}
	return ide_error(drive, "dma_intr", stat);