path: root/drivers/block/pdc202xx.c

/*
 *  linux/drivers/block/pdc202xx.c	Version 0.28	Dec. 13, 1999
 *
 *  Copyright (C) 1998-99	Andre Hedrick (andre@suse.com)
 *  May be copied or modified under the terms of the GNU General Public License
 *
 *  Promise Ultra33 cards with BIOS v1.20 through 1.28 will need this
 *  compiled into the kernel if you have more than one card installed.
 *  Note that BIOS v1.29 is reported to fix the problem.  Since this is
 *  safe chipset tuning, including this support is harmless
 *
 *  The latest chipset code will support the following ::
 *  Three Ultra33 controllers and 12 drives.
 *  8 are UDMA supported and 4 are limited to DMA mode 2 multi-word.
 *  The 8/4 ratio is a BIOS code limit by promise.
 *
 *  UNLESS you enable "CONFIG_PDC202XX_FORCE_BURST_BIT"
 *
 *  There is only one BIOS in the three contollers.
 *
 *  May  8 20:56:17 Orion kernel:
 *  Uniform Multi-Platform E-IDE driver Revision: 6.19
 *  PDC20246: IDE controller on PCI bus 00 dev a0
 *  PDC20246: not 100% native mode: will probe irqs later
 *  PDC20246: ROM enabled at 0xfebd0000
 *  PDC20246: (U)DMA Burst Bit ENABLED Primary PCI Mode Secondary PCI Mode.
 *      ide0: BM-DMA at 0xef80-0xef87, BIOS settings: hda:DMA, hdb:DMA
 *      ide1: BM-DMA at 0xef88-0xef8f, BIOS settings: hdc:pio, hdd:pio
 *  PDC20246: IDE controller on PCI bus 00 dev 98
 *  PDC20246: not 100% native mode: will probe irqs later
 *  PDC20246: ROM enabled at 0xfebc0000
 *  PDC20246: (U)DMA Burst Bit ENABLED Primary PCI Mode Secondary PCI Mode.
 *      ide2: BM-DMA at 0xef40-0xef47, BIOS settings: hde:DMA, hdf:DMA
 *      ide3: BM-DMA at 0xef48-0xef4f, BIOS settings: hdg:DMA, hdh:DMA
 *  PDC20246: IDE controller on PCI bus 00 dev 90
 *  PDC20246: not 100% native mode: will probe irqs later
 *  PDC20246: ROM enabled at 0xfebb0000
 *  PDC20246: (U)DMA Burst Bit DISABLED Primary PCI Mode Secondary PCI Mode.
 *  PDC20246: FORCING BURST BIT 0x00 -> 0x01 ACTIVE
 *      ide4: BM-DMA at 0xef00-0xef07, BIOS settings: hdi:DMA, hdj:pio
 *      ide5: BM-DMA at 0xef08-0xef0f, BIOS settings: hdk:pio, hdl:pio
 *  PIIX3: IDE controller on PCI bus 00 dev 39
 *  PIIX3: device not capable of full native PCI mode
 *
 *  ide0 at 0xeff0-0xeff7,0xefe6 on irq 19
 *  ide1 at 0xefa8-0xefaf,0xebe6 on irq 19
 *  ide2 at 0xefa0-0xefa7,0xef7e on irq 18
 *  ide3 at 0xef68-0xef6f,0xef66 on irq 18
 *  ide4 at 0xef38-0xef3f,0xef62 on irq 17
 *  hda: QUANTUM FIREBALL ST6.4A, 6149MB w/81kB Cache, CHS=13328/15/63, UDMA(33)
 *  hdb: QUANTUM FIREBALL ST3.2A, 3079MB w/81kB Cache, CHS=6256/16/63, UDMA(33)
 *  hde: Maxtor 72004 AP, 1916MB w/128kB Cache, CHS=3893/16/63, DMA
 *  hdf: Maxtor 71626 A, 1554MB w/64kB Cache, CHS=3158/16/63, DMA
 *  hdi: Maxtor 90680D4, 6485MB w/256kB Cache, CHS=13176/16/63, UDMA(33)
 *  hdj: Maxtor 90680D4, 6485MB w/256kB Cache, CHS=13176/16/63, UDMA(33)
 *
 *  Promise Ultra66 cards with BIOS v1.11 this
 *  compiled into the kernel if you have more than one card installed.
 *
 *  PDC20262: IDE controller on PCI bus 00 dev a0
 *  PDC20262: not 100% native mode: will probe irqs later
 *  PDC20262: ROM enabled at 0xfebb0000
 *  PDC20262: (U)DMA Burst Bit ENABLED Primary PCI Mode Secondary PCI Mode.
 *      ide0: BM-DMA at 0xef00-0xef07, BIOS settings: hda:pio, hdb:pio
 *      ide1: BM-DMA at 0xef08-0xef0f, BIOS settings: hdc:pio, hdd:pio
 *
 *  UDMA 4/2 and UDMA 3/1 only differ by the testing bit 13 in word93.
 *  Chipset timing speeds must be identical
 *
 *  drive_number
 *      = ((HWIF(drive)->channel ? 2 : 0) + (drive->select.b.unit & 0x01));
 *      = ((hwif->channel ? 2 : 0) + (drive->select.b.unit & 0x01));
 */

/*
 *  Portions Copyright (C) 1999 Promise Technology, Inc.
 *  Author: Frank Tiernan (frankt@promise.com)
 *  Released under terms of General Public License
 */

#include <linux/config.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/timer.h>
#include <linux/mm.h>
#include <linux/ioport.h>
#include <linux/blkdev.h>
#include <linux/hdreg.h>
#include <linux/interrupt.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/ide.h>

#include <asm/io.h>
#include <asm/irq.h>

#include "ide_modes.h"

#define PDC202XX_DEBUG_DRIVE_INFO		0
#define PDC202XX_DECODE_REGISTER_INFO		0

extern char *ide_xfer_verbose (byte xfer_rate);

/* A Register */
#define	SYNC_ERRDY_EN	0xC0

#define	SYNC_IN		0x80	/* control bit, different for master vs. slave drives */
#define	ERRDY_EN	0x40	/* control bit, different for master vs. slave drives */
#define	IORDY_EN	0x20	/* PIO: IOREADY */
#define	PREFETCH_EN	0x10	/* PIO: PREFETCH */

#define	PA3		0x08	/* PIO"A" timing */
#define	PA2		0x04	/* PIO"A" timing */
#define	PA1		0x02	/* PIO"A" timing */
#define	PA0		0x01	/* PIO"A" timing */

/* B Register */

#define	MB2		0x80	/* DMA"B" timing */
#define	MB1		0x40	/* DMA"B" timing */
#define	MB0		0x20	/* DMA"B" timing */

#define	PB4		0x10	/* PIO_FORCE 1:0 */

#define	PB3		0x08	/* PIO"B" timing */	/* PIO flow Control mode */
#define	PB2		0x04	/* PIO"B" timing */	/* PIO 4 */
#define	PB1		0x02	/* PIO"B" timing */	/* PIO 3 half */
#define	PB0		0x01	/* PIO"B" timing */	/* PIO 3 other half */

/* C Register */
#define	IORDYp_NO_SPEED	0x4F
#define	SPEED_DIS	0x0F

#define	DMARQp		0x80
#define	IORDYp		0x40
#define	DMAR_EN		0x20
#define	DMAW_EN		0x10

#define	MC3		0x08	/* DMA"C" timing */
#define	MC2		0x04	/* DMA"C" timing */
#define	MC1		0x02	/* DMA"C" timing */
#define	MC0		0x01	/* DMA"C" timing */

#if PDC202XX_DECODE_REGISTER_INFO

#define REG_A		0x01
#define REG_B		0x02
#define REG_C		0x04
#define REG_D		0x08

static void decode_registers (byte registers, byte value)
{
	byte	bit = 0, bit1 = 0, bit2 = 0;

	switch(registers) {
		case REG_A:
			bit2 = 0;
			printk("A Register ");
			if (value & 0x80) printk("SYNC_IN ");
			if (value & 0x40) printk("ERRDY_EN ");
			if (value & 0x20) printk("IORDY_EN ");
			if (value & 0x10) printk("PREFETCH_EN ");
			if (value & 0x08) { printk("PA3 ");bit2 |= 0x08; }
			if (value & 0x04) { printk("PA2 ");bit2 |= 0x04; }
			if (value & 0x02) { printk("PA1 ");bit2 |= 0x02; }
			if (value & 0x01) { printk("PA0 ");bit2 |= 0x01; }
			printk("PIO(A) = %d ", bit2);
			break;
		case REG_B:
			bit1 = 0;bit2 = 0;
			printk("B Register ");
			if (value & 0x80) { printk("MB2 ");bit1 |= 0x80; }
			if (value & 0x40) { printk("MB1 ");bit1 |= 0x40; }
			if (value & 0x20) { printk("MB0 ");bit1 |= 0x20; }
			printk("DMA(B) = %d ", bit1 >> 5);
			if (value & 0x10) printk("PIO_FORCED/PB4 ");
			if (value & 0x08) { printk("PB3 ");bit2 |= 0x08; }
			if (value & 0x04) { printk("PB2 ");bit2 |= 0x04; }
			if (value & 0x02) { printk("PB1 ");bit2 |= 0x02; }
			if (value & 0x01) { printk("PB0 ");bit2 |= 0x01; }
			printk("PIO(B) = %d ", bit2);
			break;
		case REG_C:
			bit2 = 0;
			printk("C Register ");
			if (value & 0x80) printk("DMARQp ");
			if (value & 0x40) printk("IORDYp ");
			if (value & 0x20) printk("DMAR_EN ");
			if (value & 0x10) printk("DMAW_EN ");

			if (value & 0x08) { printk("MC3 ");bit2 |= 0x08; }
			if (value & 0x04) { printk("MC2 ");bit2 |= 0x04; }
			if (value & 0x02) { printk("MC1 ");bit2 |= 0x02; }
			if (value & 0x01) { printk("MC0 ");bit2 |= 0x01; }
			printk("DMA(C) = %d ", bit2);
			break;
		case REG_D:
			printk("D Register ");
			break;
		default:
			return;
	}
	printk("\n        %s ", (registers & REG_D) ? "DP" :
				(registers & REG_C) ? "CP" :
				(registers & REG_B) ? "BP" :
				(registers & REG_A) ? "AP" : "ERROR");
	for (bit=128;bit>0;bit/=2)
		printk("%s", (value & bit) ? "1" : "0");
	printk("\n");
}

#endif /* PDC202XX_DECODE_REGISTER_INFO */

static int config_chipset_for_dma (ide_drive_t *drive, byte ultra)
{
	struct hd_driveid *id	= drive->id;
	ide_hwif_t *hwif	= HWIF(drive);
	struct pci_dev *dev	= hwif->pci_dev;
	unsigned long high_16	= dev->resource[4].start & PCI_BASE_ADDRESS_IO_MASK;

	int			err;
	unsigned int		drive_conf;
	byte			drive_pci;
	byte			test1, test2, speed = -1;
	byte			AP, BP, CP, DP, TB, TC;
	unsigned short		EP;
	byte CLKSPD		= IN_BYTE(high_16 + 0x11);
	int drive_number	= ((hwif->channel ? 2 : 0) + (drive->select.b.unit & 0x01));
	byte udma_66		= ((id->word93 & 0x2000) && (hwif->udma_four)) ? 1 : 0;
	byte udma_33		= ultra ? (inb(high_16 + 0x001f) & 1) : 0;

	/*
	 * Set the control register to use the 66Mhz system
	 * clock for UDMA 3/4 mode operation. If one drive on
	 * a channel is U66 capable but the other isn't we
	 * fall back to U33 mode. The BIOS INT 13 hooks turn
	 * the clock on then off for each read/write issued. I don't
	 * do that here because it would require modifying the
	 * kernel, seperating the fop routines from the kernel or
	 * somehow hooking the fops calls. It may also be possible to
	 * leave the 66Mhz clock on and readjust the timing
	 * parameters.
	 */

	byte mask		= hwif->channel ? 0x08 : 0x02;
	unsigned short c_mask	= hwif->channel ? (1<<11) : (1<<10);
	byte ultra_66		= ((id->dma_ultra & 0x0010) || (id->dma_ultra & 0x0008)) ? 1 : 0;

	pci_read_config_word(dev, 0x50, &EP);

	if ((ultra_66) && (EP & c_mask)) {
#ifdef DEBUG
		printk("ULTRA66: %s channel of Ultra 66 requires an 80-pin cable for Ultra66 operation.\n", hwif->channel ? "Secondary", "Primary");
		printk("         Switching to Ultra33 mode.\n");
#endif /* DEBUG */
		/* Primary   : zero out second bit */
		/* Secondary : zero out fourth bit */
		OUT_BYTE(CLKSPD & ~mask, (high_16 + 0x11));
	} else {
		if (ultra_66) {
			/*
			 * check to make sure drive on same channel
			 * is u66 capable
			 */
			if (hwif->drives[!(drive_number%2)].id) {
				if ((hwif->drives[!(drive_number%2)].id->dma_ultra & 0x0010) ||
				    (hwif->drives[!(drive_number%2)].id->dma_ultra & 0x0008)) {
					OUT_BYTE(CLKSPD | mask, (high_16 + 0x11));
				} else {
					OUT_BYTE(CLKSPD & ~mask, (high_16 + 0x11));
				}
			} else { /* udma4 drive by itself */
				OUT_BYTE(CLKSPD | mask, (high_16 + 0x11));
			}
		}
	}

	switch(drive_number) {
		case 0:	drive_pci = 0x60;
			pci_read_config_dword(dev, drive_pci, &drive_conf);
			if ((drive_conf != 0x004ff304) && (drive_conf != 0x004ff3c4))
				goto chipset_is_set;
			pci_read_config_byte(dev, (drive_pci), &test1);
			if (!(test1 & SYNC_ERRDY_EN))
				pci_write_config_byte(dev, (drive_pci), test1|SYNC_ERRDY_EN);
			break;
		case 1:	drive_pci = 0x64;
			pci_read_config_dword(dev, drive_pci, &drive_conf);
			if ((drive_conf != 0x004ff304) && (drive_conf != 0x004ff3c4))
				goto chipset_is_set;
			pci_read_config_byte(dev, 0x60, &test1);
			pci_read_config_byte(dev, (drive_pci), &test2);
			if ((test1 & SYNC_ERRDY_EN) && !(test2 & SYNC_ERRDY_EN))
				pci_write_config_byte(dev, (drive_pci), test2|SYNC_ERRDY_EN);
			break;
		case 2:	drive_pci = 0x68;
			pci_read_config_dword(dev, drive_pci, &drive_conf);
			if ((drive_conf != 0x004ff304) && (drive_conf != 0x004ff3c4))
				goto chipset_is_set;
			pci_read_config_byte(dev, (drive_pci), &test1);
			if (!(test1 & SYNC_ERRDY_EN))
				pci_write_config_byte(dev, (drive_pci), test1|SYNC_ERRDY_EN);
			break;
		case 3:	drive_pci = 0x6c;
			pci_read_config_dword(dev, drive_pci, &drive_conf);
			if ((drive_conf != 0x004ff304) && (drive_conf != 0x004ff3c4))
				goto chipset_is_set;
			pci_read_config_byte(dev, 0x68, &test1);
			pci_read_config_byte(dev, (drive_pci), &test2);
			if ((test1 & SYNC_ERRDY_EN) && !(test2 & SYNC_ERRDY_EN))
				pci_write_config_byte(dev, (drive_pci), test2|SYNC_ERRDY_EN);
			break;
		default:
			return ide_dma_off;
	}

chipset_is_set:

	if (drive->media != ide_disk)
		return ide_dma_off_quietly;

	pci_read_config_byte(dev, (drive_pci), &AP);
	pci_read_config_byte(dev, (drive_pci)|0x01, &BP);
	pci_read_config_byte(dev, (drive_pci)|0x02, &CP);
	pci_read_config_byte(dev, (drive_pci)|0x03, &DP);

	if (id->capability & 4) {		/* IORDY_EN */
		pci_write_config_byte(dev, (drive_pci), AP|IORDY_EN);
		pci_read_config_byte(dev, (drive_pci), &AP);
	}

	if (drive->media == ide_disk) {		/* PREFETCH_EN */
		pci_write_config_byte(dev, (drive_pci), AP|PREFETCH_EN);
		pci_read_config_byte(dev, (drive_pci), &AP);
	}

	if ((BP & 0xF0) && (CP & 0x0F)) {
		/* clear DMA modes of upper 842 bits of B Register */
		/* clear PIO forced mode upper 1 bit of B Register */
		pci_write_config_byte(dev, (drive_pci)|0x01, BP & ~0xF0);
		pci_read_config_byte(dev, (drive_pci)|0x01, &BP);

		/* clear DMA modes of lower 8421 bits of C Register */
		pci_write_config_byte(dev, (drive_pci)|0x02, CP & ~0x0F);
		pci_read_config_byte(dev, (drive_pci)|0x02, &CP);
	}

	pci_read_config_byte(dev, (drive_pci), &AP);
	pci_read_config_byte(dev, (drive_pci)|0x01, &BP);
	pci_read_config_byte(dev, (drive_pci)|0x02, &CP);

	if ((id->dma_ultra & 0x0010) && (udma_66) && (udma_33)) {
		/* speed 8 == UDMA mode 4 == speed 6 plus cable */
		speed = XFER_UDMA_4; TB = 0x20; TC = 0x01;
	} else if ((id->dma_ultra & 0x0008) && (udma_66) && (udma_33)) {
		/* speed 7 == UDMA mode 3 == speed 5 plus cable */
		speed = XFER_UDMA_3; TB = 0x40; TC = 0x02;
	} else if ((id->dma_ultra & 0x0004) && (udma_33)) {
		/* speed 6 == UDMA mode 2 */
		speed = XFER_UDMA_2; TB = 0x20; TC = 0x01;
	} else if ((id->dma_ultra & 0x0002) && (udma_33)) {
		/* speed 5 == UDMA mode 1 */
		speed = XFER_UDMA_1; TB = 0x40; TC = 0x02;
	} else if ((id->dma_ultra & 0x0001) && (udma_33)) {
		/* speed 4 == UDMA mode 0 */
		speed = XFER_UDMA_0; TB = 0x60; TC = 0x03;
	} else if (id->dma_mword & 0x0004) {
		/* speed 4 == DMA mode 2 multi-word */
		speed = XFER_MW_DMA_2; TB = 0x60; TC = 0x03;
	} else if (id->dma_mword & 0x0002) {
		/* speed 3 == DMA mode 1 multi-word */
		speed = XFER_MW_DMA_1; TB = 0x60; TC = 0x04;
	} else if (id->dma_mword & 0x0001) {
		/* speed 2 == DMA mode 0 multi-word */
		speed = XFER_MW_DMA_0; TB = 0x60; TC = 0x05;
	} else if (id->dma_1word & 0x0004) {
		/* speed 2 == DMA mode 2 single-word */
		speed = XFER_SW_DMA_2; TB = 0x60; TC = 0x05;
	} else if (id->dma_1word & 0x0002) {
		/* speed 1 == DMA mode 1 single-word */
		speed = XFER_SW_DMA_1; TB = 0x80; TC = 0x06;
	} else if (id->dma_1word & 0x0001) {
		/* speed 0 == DMA mode 0 single-word */
		speed = XFER_SW_DMA_0; TB = 0xC0; TC = 0x0B;
	} else {
		/* restore original pci-config space */
		pci_write_config_dword(dev, drive_pci, drive_conf);
		return ide_dma_off_quietly;
	}

	pci_write_config_byte(dev, (drive_pci)|0x01, BP|TB);
	pci_write_config_byte(dev, (drive_pci)|0x02, CP|TC);

#if PDC202XX_DECODE_REGISTER_INFO
	pci_read_config_byte(dev, (drive_pci), &AP);
	pci_read_config_byte(dev, (drive_pci)|0x01, &BP);
	pci_read_config_byte(dev, (drive_pci)|0x02, &CP);

	decode_registers(REG_A, AP);
	decode_registers(REG_B, BP);
	decode_registers(REG_C, CP);
	decode_registers(REG_D, DP);
#endif /* PDC202XX_DECODE_REGISTER_INFO */

	err = ide_config_drive_speed(drive, speed);

#if PDC202XX_DEBUG_DRIVE_INFO
	printk("%s: %s drive%d 0x%08x ",
		drive->name, ide_xfer_verbose(speed),
		drive_number, drive_conf);
	pci_read_config_dword(dev, drive_pci, &drive_conf);
	printk("0x%08x\n", drive_conf);
#endif /* PDC202XX_DEBUG_DRIVE_INFO */

	return ((int)	((id->dma_ultra >> 11) & 3) ? ide_dma_on :
			((id->dma_ultra >> 8) & 7) ? ide_dma_on :
			((id->dma_mword >> 8) & 7) ? ide_dma_on : 
			((id->dma_1word >> 8) & 7) ? ide_dma_on :
						     ide_dma_off_quietly);
}

/*   0    1    2    3    4    5    6   7   8
 * 960, 480, 390, 300, 240, 180, 120, 90, 60
 *           180, 150, 120,  90,  60
 * DMA_Speed
 * 180, 120,  90,  90,  90,  60,  30
 *  11,   5,   4,   3,   2,   1,   0
 */

static int config_chipset_for_pio (ide_drive_t *drive, byte pio)
{
	ide_hwif_t *hwif	= HWIF(drive);
	struct pci_dev *dev	= hwif->pci_dev;
	byte			drive_pci, speed;
	byte			AP, BP, TA, TB;

	int drive_number	= ((hwif->channel ? 2 : 0) + (drive->select.b.unit & 0x01));
	int err;

	switch (drive_number) {
		case 0: drive_pci = 0x60;	break;
		case 1: drive_pci = 0x64;	break;
		case 2: drive_pci = 0x68;	break;
		case 3: drive_pci = 0x6c;	break;
		default:			return 1;
	}

        pci_read_config_byte(dev, (drive_pci), &AP);
        pci_read_config_byte(dev, (drive_pci)|0x01, &BP);


        if ((AP & 0x0F) || (BP & 0x07)) {
		/* clear PIO modes of lower 8421 bits of A Register */
		pci_write_config_byte(dev, (drive_pci), AP & ~0x0F);
		pci_read_config_byte(dev, (drive_pci), &AP);

		/* clear PIO modes of lower 421 bits of B Register */
		pci_write_config_byte(dev, (drive_pci)|0x01, BP & ~0x07);
		pci_read_config_byte(dev, (drive_pci)|0x01, &BP);

		pci_read_config_byte(dev, (drive_pci), &AP);
		pci_read_config_byte(dev, (drive_pci)|0x01, &BP);
	}

	pio = (pio == 5) ? 4 : pio;
	switch (ide_get_best_pio_mode(drive, 255, pio, NULL)) {
		case 4:  speed = XFER_PIO_4; TA=0x01; TB=0x04; break;
		case 3:  speed = XFER_PIO_3; TA=0x02; TB=0x06; break;
		case 2:  speed = XFER_PIO_2; TA=0x03; TB=0x08; break;
		case 1:  speed = XFER_PIO_1; TA=0x05; TB=0x0C; break;
		case 0:
		default: speed = XFER_PIO_0; TA=0x09; TB=0x13; break;
	}
	pci_write_config_byte(dev, (drive_pci), AP|TA);
	pci_write_config_byte(dev, (drive_pci)|0x01, BP|TB);

#if PDC202XX_DECODE_REGISTER_INFO
	pci_read_config_byte(dev, (drive_pci), &AP);
	pci_read_config_byte(dev, (drive_pci)|0x01, &BP);
	pci_read_config_byte(dev, (drive_pci)|0x02, &CP);
	pci_read_config_byte(dev, (drive_pci)|0x03, &DP);

	decode_registers(REG_A, AP);
	decode_registers(REG_B, BP);
	decode_registers(REG_C, CP);
	decode_registers(REG_D, DP);
#endif /* PDC202XX_DECODE_REGISTER_INFO */

	err = ide_config_drive_speed(drive, speed);

#if PDC202XX_DEBUG_DRIVE_INFO
	printk("%s: %s drive%d 0x%08x ",
		drive->name, ide_xfer_verbose(speed),
		drive_number, drive_conf);
	pci_read_config_dword(dev, drive_pci, &drive_conf);
	printk("0x%08x\n", drive_conf);
#endif /* PDC202XX_DEBUG_DRIVE_INFO */

	return err;
}

static void pdc202xx_tune_drive (ide_drive_t *drive, byte pio)
{
	(void) config_chipset_for_pio(drive, pio);
}

static int config_drive_xfer_rate (ide_drive_t *drive)
{
	struct hd_driveid *id = drive->id;
	ide_hwif_t *hwif = HWIF(drive);
	ide_dma_action_t dma_func = ide_dma_off_quietly;

	if (id && (id->capability & 1) && hwif->autodma) {
		/* Consult the list of known "bad" drives */
		if (ide_dmaproc(ide_dma_bad_drive, drive)) {
			dma_func = ide_dma_off;
			goto fast_ata_pio;
		}
		dma_func = ide_dma_off_quietly;
		if (id->field_valid & 4) {
			if (id->dma_ultra & 0x001F) {
				/* Force if Capable UltraDMA */
				dma_func = config_chipset_for_dma(drive, 1);
				if ((id->field_valid & 2) &&
				    (dma_func != ide_dma_on))
					goto try_dma_modes;
			}
		} else if (id->field_valid & 2) {
try_dma_modes:
			if ((id->dma_mword & 0x0007) ||
			    (id->dma_1word & 0x0007)) {
				/* Force if Capable regular DMA modes */
				dma_func = config_chipset_for_dma(drive, 0);
				if (dma_func != ide_dma_on)
					goto no_dma_set;
			}
		} else if (ide_dmaproc(ide_dma_good_drive, drive)) {
			if (id->eide_dma_time > 150) {
				goto no_dma_set;
			}
			/* Consult the list of known "good" drives */
			dma_func = config_chipset_for_dma(drive, 0);
			if (dma_func != ide_dma_on)
				goto no_dma_set;
		} else {
			goto fast_ata_pio;
		}
	} else if ((id->capability & 8) || (id->field_valid & 2)) {
fast_ata_pio:
		dma_func = ide_dma_off_quietly;
no_dma_set:
		(void) config_chipset_for_pio(drive, 5);
	}

	return HWIF(drive)->dmaproc(dma_func, drive);
}

/*
 * pdc202xx_dmaproc() initiates/aborts (U)DMA read/write operations on a drive.
 */
int pdc202xx_dmaproc (ide_dma_action_t func, ide_drive_t *drive)
{
	switch (func) {
		case ide_dma_check:
			return config_drive_xfer_rate(drive);
		default:
			break;
	}
	return ide_dmaproc(func, drive);	/* use standard DMA stuff */
}

unsigned int __init pci_init_pdc202xx (struct pci_dev *dev, const char *name)
{
	unsigned long high_16	= dev->resource[4].start & PCI_BASE_ADDRESS_IO_MASK;
	byte udma_speed_flag	= inb(high_16 + 0x001f);
	byte primary_mode	= inb(high_16 + 0x001a);
	byte secondary_mode	= inb(high_16 + 0x001b);

	if (dev->device == PCI_DEVICE_ID_PROMISE_20262) {
		int i = 0;
		/*
		 * software reset -  this is required because the bios
		 * will set UDMA timing on if the hdd supports it. The
		 * user may want to turn udma off. A bug in the pdc20262
		 * is that it cannot handle a downgrade in timing from UDMA
		 * to DMA. Disk accesses after issuing a set feature command
		 * will result in errors. A software reset leaves the timing
		 * registers intact, but resets the drives.
		 */

		OUT_BYTE(udma_speed_flag | 0x10, high_16 + 0x001f);
		ide_delay_50ms();
		ide_delay_50ms();
		OUT_BYTE(udma_speed_flag & ~0x10, high_16 + 0x001f);
		for (i=0; i<40; i++)
			ide_delay_50ms();
	}

	if (dev->resource[PCI_ROM_RESOURCE].start) {
		pci_write_config_dword(dev, PCI_ROM_ADDRESS, dev->resource[PCI_ROM_RESOURCE].start | PCI_ROM_ADDRESS_ENABLE);
		printk("%s: ROM enabled at 0x%08lx\n", name, dev->resource[PCI_ROM_RESOURCE].start);
	}

	if ((dev->class >> 8) != PCI_CLASS_STORAGE_IDE) {
		byte irq = 0, irq2 = 0;
		pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
		pci_read_config_byte(dev, (PCI_INTERRUPT_LINE)|0x80, &irq2);	/* 0xbc */
		if (irq != irq2) {
			pci_write_config_byte(dev, (PCI_INTERRUPT_LINE)|0x80, irq);	/* 0xbc */
			printk("%s: pci-config space interrupt mirror fixed.\n", name);
		}
	}

	printk("%s: (U)DMA Burst Bit %sABLED " \
		"Primary %s Mode " \
		"Secondary %s Mode.\n",
		name,
		(udma_speed_flag & 1) ? "EN" : "DIS",
		(primary_mode & 1) ? "MASTER" : "PCI",
		(secondary_mode & 1) ? "MASTER" : "PCI" );

#ifdef CONFIG_PDC202XX_FORCE_BURST_BIT
	if (!(udma_speed_flag & 1)) {
		printk("%s: FORCING BURST BIT 0x%02x -> 0x%02x ", name, udma_speed_flag, (udma_speed_flag|1));
		outb(udma_speed_flag|1, high_16 + 0x001f);
		printk("%sCTIVE\n", (inb(high_16 + 0x001f) & 1) ? "A" : "INA");
	}
#endif /* CONFIG_PDC202XX_FORCE_BURST_BIT */

#ifdef CONFIG_PDC202XX_FORCE_MASTER_MODE
	if (!(primary_mode & 1)) {
		printk("%s: FORCING PRIMARY MODE BIT 0x%02x -> 0x%02x ",
			name, primary_mode, (primary_mode|1));
		outb(primary_mode|1, high_16 + 0x001a);
		printk("%s\n", (inb(high_16 + 0x001a) & 1) ? "MASTER" : "PCI");
	}

	if (!(secondary_mode & 1)) {
		printk("%s: FORCING SECONDARY MODE BIT 0x%02x -> 0x%02x ",
			name, secondary_mode, (secondary_mode|1));
		outb(secondary_mode|1, high_16 + 0x001b);
		printk("%s\n", (inb(high_16 + 0x001b) & 1) ? "MASTER" : "PCI");
	}
#endif /* CONFIG_PDC202XX_FORCE_MASTER_MODE */
	return dev->irq;
}

unsigned int __init ata66_pdc202xx (ide_hwif_t *hwif)
{
	unsigned short mask = (hwif->channel) ? (1<<11) : (1<<10);
	unsigned short CIS;

	pci_read_config_word(hwif->pci_dev, 0x50, &CIS);
        return ((CIS & mask) ? 0 : 1);
}

void __init ide_init_pdc202xx (ide_hwif_t *hwif)
{
	hwif->tuneproc = &pdc202xx_tune_drive;

	if (hwif->dma_base) {
		hwif->dmaproc = &pdc202xx_dmaproc;
		hwif->drives[0].autotune = 0;
		hwif->drives[1].autotune = 0;
	} else {
		hwif->drives[0].autotune = 1;
		hwif->drives[1].autotune = 1;
	}
}