drivers/ide/pci/cmd64x.c - kernel/msm-4.9 - Gitiles

 /*
  * linux/drivers/ide/pci/cmd64x.c		Version 1.47	Mar 19, 2007
  *
  * cmd64x.c: Enable interrupts at initialization time on Ultra/PCI machines.
  *           Due to massive hardware bugs, UltraDMA is only supported
  *           on the 646U2 and not on the 646U.
  *
  * Copyright (C) 1998		Eddie C. Dost  (ecd@skynet.be)
  * Copyright (C) 1998		David S. Miller (davem@redhat.com)
  *
  * Copyright (C) 1999-2002	Andre Hedrick <andre@linux-ide.org>
  * Copyright (C) 2007		MontaVista Software, Inc. <source@mvista.com>
  */

 #include <linux/module.h>
 #include <linux/types.h>
 #include <linux/pci.h>
 #include <linux/delay.h>
 #include <linux/hdreg.h>
 #include <linux/ide.h>
 #include <linux/init.h>

 #include <asm/io.h>

 #define DISPLAY_CMD64X_TIMINGS

 #define CMD_DEBUG 0

 #if CMD_DEBUG
 #define cmdprintk(x...)	printk(x)
 #else
 #define cmdprintk(x...)
 #endif

 /*
  * CMD64x specific registers definition.
  */
 #define CFR		0x50
 #define   CFR_INTR_CH0		0x04
 #define CNTRL		0x51
 #define   CNTRL_ENA_1ST 	0x04
 #define   CNTRL_ENA_2ND 	0x08
 #define   CNTRL_DIS_RA0 	0x40
 #define   CNTRL_DIS_RA1 	0x80

 #define	CMDTIM		0x52
 #define	ARTTIM0		0x53
 #define	DRWTIM0		0x54
 #define ARTTIM1 	0x55
 #define DRWTIM1		0x56
 #define ARTTIM23	0x57
 #define   ARTTIM23_DIS_RA2	0x04
 #define   ARTTIM23_DIS_RA3	0x08
 #define   ARTTIM23_INTR_CH1	0x10
 #define ARTTIM2		0x57
 #define ARTTIM3		0x57
 #define DRWTIM23	0x58
 #define DRWTIM2		0x58
 #define BRST		0x59
 #define DRWTIM3		0x5b

 #define BMIDECR0	0x70
 #define MRDMODE		0x71
 #define   MRDMODE_INTR_CH0	0x04
 #define   MRDMODE_INTR_CH1	0x08
 #define   MRDMODE_BLK_CH0	0x10
 #define   MRDMODE_BLK_CH1	0x20
 #define BMIDESR0	0x72
 #define UDIDETCR0	0x73
 #define DTPR0		0x74
 #define BMIDECR1	0x78
 #define BMIDECSR	0x79
 #define BMIDESR1	0x7A
 #define UDIDETCR1	0x7B
 #define DTPR1		0x7C

 #if defined(DISPLAY_CMD64X_TIMINGS) && defined(CONFIG_IDE_PROC_FS)
 #include <linux/stat.h>
 #include <linux/proc_fs.h>

 static u8 cmd64x_proc = 0;

 #define CMD_MAX_DEVS		5

 static struct pci_dev *cmd_devs[CMD_MAX_DEVS];
 static int n_cmd_devs;

 static char * print_cmd64x_get_info (char *buf, struct pci_dev *dev, int index)
 {
 	char *p = buf;
 	u8 reg72 = 0, reg73 = 0;			/* primary */
 	u8 reg7a = 0, reg7b = 0;			/* secondary */
 	u8 reg50 = 1, reg51 = 1, reg57 = 0, reg71 = 0;	/* extra */
 	u8 rev = 0;

 	p += sprintf(p, "\nController: %d\n", index);
 	p += sprintf(p, "PCI-%x Chipset.\n", dev->device);

 	(void) pci_read_config_byte(dev, CFR,       &reg50);
 	(void) pci_read_config_byte(dev, CNTRL,     &reg51);
 	(void) pci_read_config_byte(dev, ARTTIM23,  &reg57);
 	(void) pci_read_config_byte(dev, MRDMODE,   &reg71);
 	(void) pci_read_config_byte(dev, BMIDESR0,  &reg72);
 	(void) pci_read_config_byte(dev, UDIDETCR0, &reg73);
 	(void) pci_read_config_byte(dev, BMIDESR1,  &reg7a);
 	(void) pci_read_config_byte(dev, UDIDETCR1, &reg7b);

 	/* PCI0643/6 originally didn't have the primary channel enable bit */
 	(void) pci_read_config_byte(dev, PCI_REVISION_ID, &rev);
 	if ((dev->device == PCI_DEVICE_ID_CMD_643) ||
 	    (dev->device == PCI_DEVICE_ID_CMD_646 && rev < 3))
 		reg51 |= CNTRL_ENA_1ST;

 	p += sprintf(p, "---------------- Primary Channel "
 			"---------------- Secondary Channel ------------\n");
 	p += sprintf(p, "                 %s                         %s\n",
 		 (reg51 & CNTRL_ENA_1ST) ? "enabled " : "disabled",
 		 (reg51 & CNTRL_ENA_2ND) ? "enabled " : "disabled");
 	p += sprintf(p, "---------------- drive0 --------- drive1 "
 			"-------- drive0 --------- drive1 ------\n");
 	p += sprintf(p, "DMA enabled:     %s              %s"
 			"             %s              %s\n",
 		(reg72 & 0x20) ? "yes" : "no ", (reg72 & 0x40) ? "yes" : "no ",
 		(reg7a & 0x20) ? "yes" : "no ", (reg7a & 0x40) ? "yes" : "no ");
 	p += sprintf(p, "UltraDMA mode:   %s (%c)          %s (%c)",
 		( reg73 & 0x01) ? " on" : "off",
 		((reg73 & 0x30) == 0x30) ? ((reg73 & 0x04) ? '3' : '0') :
 		((reg73 & 0x30) == 0x20) ? ((reg73 & 0x04) ? '3' : '1') :
 		((reg73 & 0x30) == 0x10) ? ((reg73 & 0x04) ? '4' : '2') :
 		((reg73 & 0x30) == 0x00) ? ((reg73 & 0x04) ? '5' : '2') : '?',
 		( reg73 & 0x02) ? " on" : "off",
 		((reg73 & 0xC0) == 0xC0) ? ((reg73 & 0x08) ? '3' : '0') :
 		((reg73 & 0xC0) == 0x80) ? ((reg73 & 0x08) ? '3' : '1') :
 		((reg73 & 0xC0) == 0x40) ? ((reg73 & 0x08) ? '4' : '2') :
 		((reg73 & 0xC0) == 0x00) ? ((reg73 & 0x08) ? '5' : '2') : '?');
 	p += sprintf(p, "         %s (%c)          %s (%c)\n",
 		( reg7b & 0x01) ? " on" : "off",
 		((reg7b & 0x30) == 0x30) ? ((reg7b & 0x04) ? '3' : '0') :
 		((reg7b & 0x30) == 0x20) ? ((reg7b & 0x04) ? '3' : '1') :
 		((reg7b & 0x30) == 0x10) ? ((reg7b & 0x04) ? '4' : '2') :
 		((reg7b & 0x30) == 0x00) ? ((reg7b & 0x04) ? '5' : '2') : '?',
 		( reg7b & 0x02) ? " on" : "off",
 		((reg7b & 0xC0) == 0xC0) ? ((reg7b & 0x08) ? '3' : '0') :
 		((reg7b & 0xC0) == 0x80) ? ((reg7b & 0x08) ? '3' : '1') :
 		((reg7b & 0xC0) == 0x40) ? ((reg7b & 0x08) ? '4' : '2') :
 		((reg7b & 0xC0) == 0x00) ? ((reg7b & 0x08) ? '5' : '2') : '?');
 	p += sprintf(p, "Interrupt:       %s, %s                 %s, %s\n",
 		(reg71 & MRDMODE_BLK_CH0  ) ? "blocked" : "enabled",
 		(reg50 & CFR_INTR_CH0	  ) ? "pending" : "clear  ",
 		(reg71 & MRDMODE_BLK_CH1  ) ? "blocked" : "enabled",
 		(reg57 & ARTTIM23_INTR_CH1) ? "pending" : "clear  ");

 	return (char *)p;
 }

 static int cmd64x_get_info (char *buffer, char **addr, off_t offset, int count)
 {
 	char *p = buffer;
 	int i;

 	for (i = 0; i < n_cmd_devs; i++) {
 		struct pci_dev *dev	= cmd_devs[i];
 		p = print_cmd64x_get_info(p, dev, i);
 	}
 	return p-buffer;	/* => must be less than 4k! */
 }

 #endif	/* defined(DISPLAY_CMD64X_TIMINGS) && defined(CONFIG_IDE_PROC_FS) */

 static u8 quantize_timing(int timing, int quant)
 {
 	return (timing + quant - 1) / quant;
 }

 /*
  * This routine calculates active/recovery counts and then writes them into
  * the chipset registers.
  */
 static void program_cycle_times (ide_drive_t *drive, int cycle_time, int active_time)
 {
 	struct pci_dev *dev	= HWIF(drive)->pci_dev;
 	int clock_time		= 1000 / system_bus_clock();
 	u8  cycle_count, active_count, recovery_count, drwtim;
 	static const u8 recovery_values[] =
 		{15, 15, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 0};
 	static const u8 drwtim_regs[4] = {DRWTIM0, DRWTIM1, DRWTIM2, DRWTIM3};

 	cmdprintk("program_cycle_times parameters: total=%d, active=%d\n",
 		  cycle_time, active_time);

 	cycle_count	= quantize_timing( cycle_time, clock_time);
 	active_count	= quantize_timing(active_time, clock_time);
 	recovery_count	= cycle_count - active_count;

 	/*
 	 * In case we've got too long recovery phase, try to lengthen
 	 * the active phase
 	 */
 	if (recovery_count > 16) {
 		active_count += recovery_count - 16;
 		recovery_count = 16;
 	}
 	if (active_count > 16)		/* shouldn't actually happen... */
 	 	active_count = 16;

 	cmdprintk("Final counts: total=%d, active=%d, recovery=%d\n",
 		  cycle_count, active_count, recovery_count);

 	/*
 	 * Convert values to internal chipset representation
 	 */
 	recovery_count = recovery_values[recovery_count];
  	active_count  &= 0x0f;

 	/* Program the active/recovery counts into the DRWTIM register */
 	drwtim = (active_count << 4) | recovery_count;
 	(void) pci_write_config_byte(dev, drwtim_regs[drive->dn], drwtim);
 	cmdprintk("Write 0x%02x to reg 0x%x\n", drwtim, drwtim_regs[drive->dn]);
 }

 /*
  * This routine selects drive's best PIO mode and writes into the chipset
  * registers setup/active/recovery timings.
  */
 static u8 cmd64x_tune_pio (ide_drive_t *drive, u8 mode_wanted)
 {
 	ide_hwif_t *hwif	= HWIF(drive);
 	struct pci_dev *dev	= hwif->pci_dev;
 	ide_pio_data_t pio;
 	u8 pio_mode, setup_count, arttim = 0;
 	static const u8 setup_values[] = {0x40, 0x40, 0x40, 0x80, 0, 0xc0};
 	static const u8 arttim_regs[4] = {ARTTIM0, ARTTIM1, ARTTIM23, ARTTIM23};
 	pio_mode = ide_get_best_pio_mode(drive, mode_wanted, 5, &pio);

 	cmdprintk("%s: PIO mode wanted %d, selected %d (%d ns)%s\n",
 		  drive->name, mode_wanted, pio_mode, pio.cycle_time,
 		  pio.overridden ? " (overriding vendor mode)" : "");

 	program_cycle_times(drive, pio.cycle_time,
 			    ide_pio_timings[pio_mode].active_time);

 	setup_count = quantize_timing(ide_pio_timings[pio_mode].setup_time,
 				      1000 / system_bus_clock());

 	/*
 	 * The primary channel has individual address setup timing registers
 	 * for each drive and the hardware selects the slowest timing itself.
 	 * The secondary channel has one common register and we have to select
 	 * the slowest address setup timing ourselves.
 	 */
 	if (hwif->channel) {
 		ide_drive_t *drives = hwif->drives;

 		drive->drive_data = setup_count;
 		setup_count = max(drives[0].drive_data, drives[1].drive_data);
 	}

 	if (setup_count > 5)		/* shouldn't actually happen... */
 		setup_count = 5;
 	cmdprintk("Final address setup count: %d\n", setup_count);

 	/*
 	 * Program the address setup clocks into the ARTTIM registers.
 	 * Avoid clearing the secondary channel's interrupt bit.
 	 */
 	(void) pci_read_config_byte (dev, arttim_regs[drive->dn], &arttim);
 	if (hwif->channel)
 		arttim &= ~ARTTIM23_INTR_CH1;
 	arttim &= ~0xc0;
 	arttim |= setup_values[setup_count];
 	(void) pci_write_config_byte(dev, arttim_regs[drive->dn], arttim);
 	cmdprintk("Write 0x%02x to reg 0x%x\n", arttim, arttim_regs[drive->dn]);

 	return pio_mode;
 }

 /*
  * Attempts to set drive's PIO mode.
  * Special cases are 8: prefetch off, 9: prefetch on (both never worked),
  * and 255: auto-select best mode (used at boot time).
  */
 static void cmd64x_tune_drive (ide_drive_t *drive, u8 pio)
 {
 	/*
 	 * Filter out the prefetch control values
 	 * to prevent PIO5 from being programmed
 	 */
 	if (pio == 8 || pio == 9)
 		return;

 	pio = cmd64x_tune_pio(drive, pio);
 	(void) ide_config_drive_speed(drive, XFER_PIO_0 + pio);
 }

 static int cmd64x_tune_chipset (ide_drive_t *drive, u8 speed)
 {
 	ide_hwif_t *hwif	= HWIF(drive);
 	struct pci_dev *dev	= hwif->pci_dev;
 	u8 unit			= drive->dn & 0x01;
 	u8 regU = 0, pciU	= hwif->channel ? UDIDETCR1 : UDIDETCR0;

 	speed = ide_rate_filter(drive, speed);

 	if (speed >= XFER_SW_DMA_0) {
 		(void) pci_read_config_byte(dev, pciU, &regU);
 		regU &= ~(unit ? 0xCA : 0x35);
 	}

 	switch(speed) {
 	case XFER_UDMA_5:
 		regU |= unit ? 0x0A : 0x05;
 		break;
 	case XFER_UDMA_4:
 		regU |= unit ? 0x4A : 0x15;
 		break;
 	case XFER_UDMA_3:
 		regU |= unit ? 0x8A : 0x25;
 		break;
 	case XFER_UDMA_2:
 		regU |= unit ? 0x42 : 0x11;
 		break;
 	case XFER_UDMA_1:
 		regU |= unit ? 0x82 : 0x21;
 		break;
 	case XFER_UDMA_0:
 		regU |= unit ? 0xC2 : 0x31;
 		break;
 	case XFER_MW_DMA_2:
 		program_cycle_times(drive, 120, 70);
 		break;
 	case XFER_MW_DMA_1:
 		program_cycle_times(drive, 150, 80);
 		break;
 	case XFER_MW_DMA_0:
 		program_cycle_times(drive, 480, 215);
 		break;
 	case XFER_PIO_5:
 	case XFER_PIO_4:
 	case XFER_PIO_3:
 	case XFER_PIO_2:
 	case XFER_PIO_1:
 	case XFER_PIO_0:
 		(void) cmd64x_tune_pio(drive, speed - XFER_PIO_0);
 		break;
 	default:
 		return 1;
 	}

 	if (speed >= XFER_SW_DMA_0)
 		(void) pci_write_config_byte(dev, pciU, regU);

 	return ide_config_drive_speed(drive, speed);
 }

 static int cmd64x_config_drive_for_dma (ide_drive_t *drive)
 {
 	if (ide_tune_dma(drive))
 		return 0;

 	if (ide_use_fast_pio(drive))
 		cmd64x_tune_drive(drive, 255);

 	return -1;
 }

 static int cmd648_ide_dma_end (ide_drive_t *drive)
 {
 	ide_hwif_t *hwif	= HWIF(drive);
 	int err			= __ide_dma_end(drive);
 	u8  irq_mask		= hwif->channel ? MRDMODE_INTR_CH1 :
 						  MRDMODE_INTR_CH0;
 	u8  mrdmode		= inb(hwif->dma_master + 0x01);

 	/* clear the interrupt bit */
 	outb(mrdmode | irq_mask, hwif->dma_master + 0x01);

 	return err;
 }

 static int cmd64x_ide_dma_end (ide_drive_t *drive)
 {
 	ide_hwif_t *hwif	= HWIF(drive);
 	struct pci_dev *dev	= hwif->pci_dev;
 	int irq_reg		= hwif->channel ? ARTTIM23 : CFR;
 	u8  irq_mask		= hwif->channel ? ARTTIM23_INTR_CH1 :
 						  CFR_INTR_CH0;
 	u8  irq_stat		= 0;
 	int err			= __ide_dma_end(drive);

 	(void) pci_read_config_byte(dev, irq_reg, &irq_stat);
 	/* clear the interrupt bit */
 	(void) pci_write_config_byte(dev, irq_reg, irq_stat | irq_mask);

 	return err;
 }

 static int cmd648_ide_dma_test_irq (ide_drive_t *drive)
 {
 	ide_hwif_t *hwif	= HWIF(drive);
 	u8 irq_mask		= hwif->channel ? MRDMODE_INTR_CH1 :
 						  MRDMODE_INTR_CH0;
 	u8 dma_stat		= inb(hwif->dma_status);
 	u8 mrdmode		= inb(hwif->dma_master + 0x01);

 #ifdef DEBUG
 	printk("%s: dma_stat: 0x%02x mrdmode: 0x%02x irq_mask: 0x%02x\n",
 	       drive->name, dma_stat, mrdmode, irq_mask);
 #endif
 	if (!(mrdmode & irq_mask))
 		return 0;

 	/* return 1 if INTR asserted */
 	if (dma_stat & 4)
 		return 1;

 	return 0;
 }

 static int cmd64x_ide_dma_test_irq (ide_drive_t *drive)
 {
 	ide_hwif_t *hwif	= HWIF(drive);
 	struct pci_dev *dev	= hwif->pci_dev;
 	int irq_reg		= hwif->channel ? ARTTIM23 : CFR;
 	u8  irq_mask		= hwif->channel ? ARTTIM23_INTR_CH1 :
 						  CFR_INTR_CH0;
 	u8  dma_stat		= inb(hwif->dma_status);
 	u8  irq_stat		= 0;

 	(void) pci_read_config_byte(dev, irq_reg, &irq_stat);

 #ifdef DEBUG
 	printk("%s: dma_stat: 0x%02x irq_stat: 0x%02x irq_mask: 0x%02x\n",
 	       drive->name, dma_stat, irq_stat, irq_mask);
 #endif
 	if (!(irq_stat & irq_mask))
 		return 0;

 	/* return 1 if INTR asserted */
 	if (dma_stat & 4)
 		return 1;

 	return 0;
 }

 /*
  * ASUS P55T2P4D with CMD646 chipset revision 0x01 requires the old
  * event order for DMA transfers.
  */

 static int cmd646_1_ide_dma_end (ide_drive_t *drive)
 {
 	ide_hwif_t *hwif = HWIF(drive);
 	u8 dma_stat = 0, dma_cmd = 0;

 	drive->waiting_for_dma = 0;
 	/* get DMA status */
 	dma_stat = inb(hwif->dma_status);
 	/* read DMA command state */
 	dma_cmd = inb(hwif->dma_command);
 	/* stop DMA */
 	outb(dma_cmd & ~1, hwif->dma_command);
 	/* clear the INTR & ERROR bits */
 	outb(dma_stat | 6, hwif->dma_status);
 	/* and free any DMA resources */
 	ide_destroy_dmatable(drive);
 	/* verify good DMA status */
 	return (dma_stat & 7) != 4;
 }

 static unsigned int __devinit init_chipset_cmd64x(struct pci_dev *dev, const char *name)
 {
 	u32 class_rev = 0;
 	u8 mrdmode = 0;

 	pci_read_config_dword(dev, PCI_CLASS_REVISION, &class_rev);
 	class_rev &= 0xff;

 	switch(dev->device) {
 		case PCI_DEVICE_ID_CMD_643:
 			break;
 		case PCI_DEVICE_ID_CMD_646:
 			printk(KERN_INFO "%s: chipset revision 0x%02X, ", name, class_rev);
 			switch(class_rev) {
 				case 0x07:
 				case 0x05:
 					printk("UltraDMA Capable");
 					break;
 				case 0x03:
 					printk("MultiWord DMA Force Limited");
 					break;
 				case 0x01:
 				default:
 					printk("MultiWord DMA Limited, IRQ workaround enabled");
 					break;
 				}
 			printk("\n");
                         break;
 		case PCI_DEVICE_ID_CMD_648:
 		case PCI_DEVICE_ID_CMD_649:
 			break;
 		default:
 			break;
 	}

 	/* Set a good latency timer and cache line size value. */
 	(void) pci_write_config_byte(dev, PCI_LATENCY_TIMER, 64);
 	/* FIXME: pci_set_master() to ensure a good latency timer value */

 	/* Setup interrupts. */
 	(void) pci_read_config_byte(dev, MRDMODE, &mrdmode);
 	mrdmode &= ~(0x30);
 	(void) pci_write_config_byte(dev, MRDMODE, mrdmode);

 	/* Use MEMORY READ LINE for reads.
 	 * NOTE: Although not mentioned in the PCI0646U specs,
 	 *       these bits are write only and won't be read
 	 *       back as set or not.  The PCI0646U2 specs clarify
 	 *       this point.
 	 */
 	(void) pci_write_config_byte(dev, MRDMODE, mrdmode | 0x02);

 	/* Set reasonable active/recovery/address-setup values. */
 	(void) pci_write_config_byte(dev, ARTTIM0,  0x40);
 	(void) pci_write_config_byte(dev, DRWTIM0,  0x3f);
 	(void) pci_write_config_byte(dev, ARTTIM1,  0x40);
 	(void) pci_write_config_byte(dev, DRWTIM1,  0x3f);
 #ifdef __i386__
 	(void) pci_write_config_byte(dev, ARTTIM23, 0x1c);
 #else
 	(void) pci_write_config_byte(dev, ARTTIM23, 0x5c);
 #endif
 	(void) pci_write_config_byte(dev, DRWTIM23, 0x3f);
 	(void) pci_write_config_byte(dev, DRWTIM3,  0x3f);
 #ifdef CONFIG_PPC
 	(void) pci_write_config_byte(dev, UDIDETCR0, 0xf0);
 #endif /* CONFIG_PPC */

 #if defined(DISPLAY_CMD64X_TIMINGS) && defined(CONFIG_IDE_PROC_FS)

 	cmd_devs[n_cmd_devs++] = dev;

 	if (!cmd64x_proc) {
 		cmd64x_proc = 1;
 		ide_pci_create_host_proc("cmd64x", cmd64x_get_info);
 	}
 #endif /* DISPLAY_CMD64X_TIMINGS && CONFIG_IDE_PROC_FS */

 	return 0;
 }

 static unsigned int __devinit ata66_cmd64x(ide_hwif_t *hwif)
 {
 	u8 ata66 = 0, mask = (hwif->channel) ? 0x02 : 0x01;

 	switch(hwif->pci_dev->device) {
 		case PCI_DEVICE_ID_CMD_643:
 		case PCI_DEVICE_ID_CMD_646:
 			return ata66;
 		default:
 			break;
 	}
 	pci_read_config_byte(hwif->pci_dev, BMIDECSR, &ata66);
 	return (ata66 & mask) ? 1 : 0;
 }

 static void __devinit init_hwif_cmd64x(ide_hwif_t *hwif)
 {
 	struct pci_dev *dev	= hwif->pci_dev;
 	unsigned int class_rev;

 	hwif->autodma = 0;
 	pci_read_config_dword(dev, PCI_CLASS_REVISION, &class_rev);
 	class_rev &= 0xff;

 	hwif->tuneproc  = &cmd64x_tune_drive;
 	hwif->speedproc = &cmd64x_tune_chipset;

 	hwif->drives[0].autotune = hwif->drives[1].autotune = 1;

 	if (!hwif->dma_base)
 		return;

 	hwif->atapi_dma = 1;

 	hwif->ultra_mask = hwif->cds->udma_mask;

 	/*
 	 * UltraDMA only supported on PCI646U and PCI646U2, which
 	 * correspond to revisions 0x03, 0x05 and 0x07 respectively.
 	 * Actually, although the CMD tech support people won't
 	 * tell me the details, the 0x03 revision cannot support
 	 * UDMA correctly without hardware modifications, and even
 	 * then it only works with Quantum disks due to some
 	 * hold time assumptions in the 646U part which are fixed
 	 * in the 646U2.
 	 *
 	 * So we only do UltraDMA on revision 0x05 and 0x07 chipsets.
 	 */
 	if (dev->device == PCI_DEVICE_ID_CMD_646 && class_rev < 5)
 		hwif->ultra_mask = 0x00;

 	hwif->mwdma_mask = 0x07;

 	hwif->ide_dma_check = &cmd64x_config_drive_for_dma;
 	if (!(hwif->udma_four))
 		hwif->udma_four = ata66_cmd64x(hwif);

 	switch(dev->device) {
 	case PCI_DEVICE_ID_CMD_648:
 	case PCI_DEVICE_ID_CMD_649:
 	alt_irq_bits:
 		hwif->ide_dma_end	= &cmd648_ide_dma_end;
 		hwif->ide_dma_test_irq	= &cmd648_ide_dma_test_irq;
 		break;
 	case PCI_DEVICE_ID_CMD_646:
 		hwif->chipset = ide_cmd646;
 		if (class_rev == 0x01) {
 			hwif->ide_dma_end = &cmd646_1_ide_dma_end;
 			break;
 		} else if (class_rev >= 0x03)
 			goto alt_irq_bits;
 		/* fall thru */
 	default:
 		hwif->ide_dma_end	= &cmd64x_ide_dma_end;
 		hwif->ide_dma_test_irq	= &cmd64x_ide_dma_test_irq;
 		break;
 	}


 	if (!noautodma)
 		hwif->autodma = 1;
 	hwif->drives[0].autodma = hwif->autodma;
 	hwif->drives[1].autodma = hwif->autodma;
 }

 static int __devinit init_setup_cmd64x(struct pci_dev *dev, ide_pci_device_t *d)
 {
 	return ide_setup_pci_device(dev, d);
 }

 static int __devinit init_setup_cmd646(struct pci_dev *dev, ide_pci_device_t *d)
 {
 	u8 rev = 0;

 	/*
 	 * The original PCI0646 didn't have the primary channel enable bit,
 	 * it appeared starting with PCI0646U (i.e. revision ID 3).
 	 */
 	pci_read_config_byte(dev, PCI_REVISION_ID, &rev);
 	if (rev < 3)
 		d->enablebits[0].reg = 0;

 	return ide_setup_pci_device(dev, d);
 }

 static ide_pci_device_t cmd64x_chipsets[] __devinitdata = {
 	{	/* 0 */
 		.name		= "CMD643",
 		.init_setup	= init_setup_cmd64x,
 		.init_chipset	= init_chipset_cmd64x,
 		.init_hwif	= init_hwif_cmd64x,
 		.channels	= 2,
 		.autodma	= AUTODMA,
 		.enablebits	= {{0x00,0x00,0x00}, {0x51,0x08,0x08}},
 		.bootable	= ON_BOARD,
 		.udma_mask	= 0x00, /* no udma */
 	},{	/* 1 */
 		.name		= "CMD646",
 		.init_setup	= init_setup_cmd646,
 		.init_chipset	= init_chipset_cmd64x,
 		.init_hwif	= init_hwif_cmd64x,
 		.channels	= 2,
 		.autodma	= AUTODMA,
 		.enablebits	= {{0x51,0x04,0x04}, {0x51,0x08,0x08}},
 		.bootable	= ON_BOARD,
 		.udma_mask	= 0x07, /* udma0-2 */
 	},{	/* 2 */
 		.name		= "CMD648",
 		.init_setup	= init_setup_cmd64x,
 		.init_chipset	= init_chipset_cmd64x,
 		.init_hwif	= init_hwif_cmd64x,
 		.channels	= 2,
 		.autodma	= AUTODMA,
 		.enablebits	= {{0x51,0x04,0x04}, {0x51,0x08,0x08}},
 		.bootable	= ON_BOARD,
 		.udma_mask	= 0x1f, /* udma0-4 */
 	},{	/* 3 */
 		.name		= "CMD649",
 		.init_setup	= init_setup_cmd64x,
 		.init_chipset	= init_chipset_cmd64x,
 		.init_hwif	= init_hwif_cmd64x,
 		.channels	= 2,
 		.autodma	= AUTODMA,
 		.enablebits	= {{0x51,0x04,0x04}, {0x51,0x08,0x08}},
 		.bootable	= ON_BOARD,
 		.udma_mask	= 0x3f, /* udma0-5 */
 	}
 };

 /*
  * We may have to modify enablebits for PCI0646, so we'd better pass
  * a local copy of the ide_pci_device_t structure down the call chain...
  */
 static int __devinit cmd64x_init_one(struct pci_dev *dev, const struct pci_device_id *id)
 {
 	ide_pci_device_t d = cmd64x_chipsets[id->driver_data];

 	return d.init_setup(dev, &d);
 }

 static struct pci_device_id cmd64x_pci_tbl[] = {
 	{ PCI_VENDOR_ID_CMD, PCI_DEVICE_ID_CMD_643, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
 	{ PCI_VENDOR_ID_CMD, PCI_DEVICE_ID_CMD_646, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 1},
 	{ PCI_VENDOR_ID_CMD, PCI_DEVICE_ID_CMD_648, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 2},
 	{ PCI_VENDOR_ID_CMD, PCI_DEVICE_ID_CMD_649, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 3},
 	{ 0, },
 };
 MODULE_DEVICE_TABLE(pci, cmd64x_pci_tbl);

 static struct pci_driver driver = {
 	.name		= "CMD64x_IDE",
 	.id_table	= cmd64x_pci_tbl,
 	.probe		= cmd64x_init_one,
 };

 static int __init cmd64x_ide_init(void)
 {
 	return ide_pci_register_driver(&driver);
 }

 module_init(cmd64x_ide_init);

 MODULE_AUTHOR("Eddie Dost, David Miller, Andre Hedrick");
 MODULE_DESCRIPTION("PCI driver module for CMD64x IDE");
 MODULE_LICENSE("GPL");
	/*
	* linux/drivers/ide/pci/cmd64x.c Version 1.47 Mar 19, 2007
	*
	* cmd64x.c: Enable interrupts at initialization time on Ultra/PCI machines.
	* Due to massive hardware bugs, UltraDMA is only supported
	* on the 646U2 and not on the 646U.
	*
	* Copyright (C) 1998 Eddie C. Dost (ecd@skynet.be)
	* Copyright (C) 1998 David S. Miller (davem@redhat.com)
	*
	* Copyright (C) 1999-2002 Andre Hedrick <andre@linux-ide.org>
	* Copyright (C) 2007 MontaVista Software, Inc. <source@mvista.com>
	*/

	#include <linux/module.h>
	#include <linux/types.h>
	#include <linux/pci.h>
	#include <linux/delay.h>
	#include <linux/hdreg.h>
	#include <linux/ide.h>
	#include <linux/init.h>

	#include <asm/io.h>

	#define DISPLAY_CMD64X_TIMINGS

	#define CMD_DEBUG 0

	#if CMD_DEBUG
	#define cmdprintk(x...) printk(x)
	#else
	#define cmdprintk(x...)
	#endif

	/*
	* CMD64x specific registers definition.
	*/
	#define CFR 0x50
	#define CFR_INTR_CH0 0x04
	#define CNTRL 0x51
	#define CNTRL_ENA_1ST 0x04
	#define CNTRL_ENA_2ND 0x08
	#define CNTRL_DIS_RA0 0x40
	#define CNTRL_DIS_RA1 0x80

	#define CMDTIM 0x52
	#define ARTTIM0 0x53
	#define DRWTIM0 0x54
	#define ARTTIM1 0x55
	#define DRWTIM1 0x56
	#define ARTTIM23 0x57
	#define ARTTIM23_DIS_RA2 0x04
	#define ARTTIM23_DIS_RA3 0x08
	#define ARTTIM23_INTR_CH1 0x10
	#define ARTTIM2 0x57
	#define ARTTIM3 0x57
	#define DRWTIM23 0x58
	#define DRWTIM2 0x58
	#define BRST 0x59
	#define DRWTIM3 0x5b

	#define BMIDECR0 0x70
	#define MRDMODE 0x71
	#define MRDMODE_INTR_CH0 0x04
	#define MRDMODE_INTR_CH1 0x08
	#define MRDMODE_BLK_CH0 0x10
	#define MRDMODE_BLK_CH1 0x20
	#define BMIDESR0 0x72
	#define UDIDETCR0 0x73
	#define DTPR0 0x74
	#define BMIDECR1 0x78
	#define BMIDECSR 0x79
	#define BMIDESR1 0x7A
	#define UDIDETCR1 0x7B
	#define DTPR1 0x7C

	#if defined(DISPLAY_CMD64X_TIMINGS) && defined(CONFIG_IDE_PROC_FS)
	#include <linux/stat.h>
	#include <linux/proc_fs.h>

	static u8 cmd64x_proc = 0;

	#define CMD_MAX_DEVS 5

	static struct pci_dev *cmd_devs[CMD_MAX_DEVS];
	static int n_cmd_devs;

	static char * print_cmd64x_get_info (char buf, struct pci_dev dev, int index)
	{
	char *p = buf;
	u8 reg72 = 0, reg73 = 0; /* primary */
	u8 reg7a = 0, reg7b = 0; /* secondary */
	u8 reg50 = 1, reg51 = 1, reg57 = 0, reg71 = 0; /* extra */
	u8 rev = 0;

	p += sprintf(p, "\nController: %d\n", index);
	p += sprintf(p, "PCI-%x Chipset.\n", dev->device);

	(void) pci_read_config_byte(dev, CFR, &reg50);
	(void) pci_read_config_byte(dev, CNTRL, &reg51);
	(void) pci_read_config_byte(dev, ARTTIM23, &reg57);
	(void) pci_read_config_byte(dev, MRDMODE, &reg71);
	(void) pci_read_config_byte(dev, BMIDESR0, &reg72);
	(void) pci_read_config_byte(dev, UDIDETCR0, &reg73);
	(void) pci_read_config_byte(dev, BMIDESR1, &reg7a);
	(void) pci_read_config_byte(dev, UDIDETCR1, &reg7b);

	/* PCI0643/6 originally didn't have the primary channel enable bit */
	(void) pci_read_config_byte(dev, PCI_REVISION_ID, &rev);
	if ((dev->device == PCI_DEVICE_ID_CMD_643) \|\|
	(dev->device == PCI_DEVICE_ID_CMD_646 && rev < 3))
	reg51 \|= CNTRL_ENA_1ST;

	p += sprintf(p, "---------------- Primary Channel "
	"---------------- Secondary Channel ------------\n");
	p += sprintf(p, " %s %s\n",
	(reg51 & CNTRL_ENA_1ST) ? "enabled " : "disabled",
	(reg51 & CNTRL_ENA_2ND) ? "enabled " : "disabled");
	p += sprintf(p, "---------------- drive0 --------- drive1 "
	"-------- drive0 --------- drive1 ------\n");
	p += sprintf(p, "DMA enabled: %s %s"
	" %s %s\n",
	(reg72 & 0x20) ? "yes" : "no ", (reg72 & 0x40) ? "yes" : "no ",
	(reg7a & 0x20) ? "yes" : "no ", (reg7a & 0x40) ? "yes" : "no ");
	p += sprintf(p, "UltraDMA mode: %s (%c) %s (%c)",
	( reg73 & 0x01) ? " on" : "off",
	((reg73 & 0x30) == 0x30) ? ((reg73 & 0x04) ? '3' : '0') :
	((reg73 & 0x30) == 0x20) ? ((reg73 & 0x04) ? '3' : '1') :
	((reg73 & 0x30) == 0x10) ? ((reg73 & 0x04) ? '4' : '2') :
	((reg73 & 0x30) == 0x00) ? ((reg73 & 0x04) ? '5' : '2') : '?',
	( reg73 & 0x02) ? " on" : "off",
	((reg73 & 0xC0) == 0xC0) ? ((reg73 & 0x08) ? '3' : '0') :
	((reg73 & 0xC0) == 0x80) ? ((reg73 & 0x08) ? '3' : '1') :
	((reg73 & 0xC0) == 0x40) ? ((reg73 & 0x08) ? '4' : '2') :
	((reg73 & 0xC0) == 0x00) ? ((reg73 & 0x08) ? '5' : '2') : '?');
	p += sprintf(p, " %s (%c) %s (%c)\n",
	( reg7b & 0x01) ? " on" : "off",
	((reg7b & 0x30) == 0x30) ? ((reg7b & 0x04) ? '3' : '0') :
	((reg7b & 0x30) == 0x20) ? ((reg7b & 0x04) ? '3' : '1') :
	((reg7b & 0x30) == 0x10) ? ((reg7b & 0x04) ? '4' : '2') :
	((reg7b & 0x30) == 0x00) ? ((reg7b & 0x04) ? '5' : '2') : '?',
	( reg7b & 0x02) ? " on" : "off",
	((reg7b & 0xC0) == 0xC0) ? ((reg7b & 0x08) ? '3' : '0') :
	((reg7b & 0xC0) == 0x80) ? ((reg7b & 0x08) ? '3' : '1') :
	((reg7b & 0xC0) == 0x40) ? ((reg7b & 0x08) ? '4' : '2') :
	((reg7b & 0xC0) == 0x00) ? ((reg7b & 0x08) ? '5' : '2') : '?');
	p += sprintf(p, "Interrupt: %s, %s %s, %s\n",
	(reg71 & MRDMODE_BLK_CH0 ) ? "blocked" : "enabled",
	(reg50 & CFR_INTR_CH0 ) ? "pending" : "clear ",
	(reg71 & MRDMODE_BLK_CH1 ) ? "blocked" : "enabled",
	(reg57 & ARTTIM23_INTR_CH1) ? "pending" : "clear ");

	return (char *)p;
	}

	static int cmd64x_get_info (char buffer, char *addr, off_t offset, int count)
	{
	char *p = buffer;
	int i;

	for (i = 0; i < n_cmd_devs; i++) {
	struct pci_dev *dev = cmd_devs[i];
	p = print_cmd64x_get_info(p, dev, i);
	}
	return p-buffer; /* => must be less than 4k! */
	}

	#endif /* defined(DISPLAY_CMD64X_TIMINGS) && defined(CONFIG_IDE_PROC_FS) */

	static u8 quantize_timing(int timing, int quant)
	{
	return (timing + quant - 1) / quant;
	}

	/*
	* This routine calculates active/recovery counts and then writes them into
	* the chipset registers.
	*/
	static void program_cycle_times (ide_drive_t *drive, int cycle_time, int active_time)
	{
	struct pci_dev *dev = HWIF(drive)->pci_dev;
	int clock_time = 1000 / system_bus_clock();
	u8 cycle_count, active_count, recovery_count, drwtim;
	static const u8 recovery_values[] =
	{15, 15, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 0};
	static const u8 drwtim_regs[4] = {DRWTIM0, DRWTIM1, DRWTIM2, DRWTIM3};

	cmdprintk("program_cycle_times parameters: total=%d, active=%d\n",
	cycle_time, active_time);

	cycle_count = quantize_timing( cycle_time, clock_time);
	active_count = quantize_timing(active_time, clock_time);
	recovery_count = cycle_count - active_count;

	/*
	* In case we've got too long recovery phase, try to lengthen
	* the active phase
	*/
	if (recovery_count > 16) {
	active_count += recovery_count - 16;
	recovery_count = 16;
	}
	if (active_count > 16) /* shouldn't actually happen... */
	active_count = 16;

	cmdprintk("Final counts: total=%d, active=%d, recovery=%d\n",
	cycle_count, active_count, recovery_count);

	/*
	* Convert values to internal chipset representation
	*/
	recovery_count = recovery_values[recovery_count];
	active_count &= 0x0f;

	/* Program the active/recovery counts into the DRWTIM register */
	drwtim = (active_count << 4) \| recovery_count;
	(void) pci_write_config_byte(dev, drwtim_regs[drive->dn], drwtim);
	cmdprintk("Write 0x%02x to reg 0x%x\n", drwtim, drwtim_regs[drive->dn]);
	}

	/*
	* This routine selects drive's best PIO mode and writes into the chipset
	* registers setup/active/recovery timings.
	*/
	static u8 cmd64x_tune_pio (ide_drive_t *drive, u8 mode_wanted)
	{
	ide_hwif_t *hwif = HWIF(drive);
	struct pci_dev *dev = hwif->pci_dev;
	ide_pio_data_t pio;
	u8 pio_mode, setup_count, arttim = 0;
	static const u8 setup_values[] = {0x40, 0x40, 0x40, 0x80, 0, 0xc0};
	static const u8 arttim_regs[4] = {ARTTIM0, ARTTIM1, ARTTIM23, ARTTIM23};
	pio_mode = ide_get_best_pio_mode(drive, mode_wanted, 5, &pio);

	cmdprintk("%s: PIO mode wanted %d, selected %d (%d ns)%s\n",
	drive->name, mode_wanted, pio_mode, pio.cycle_time,
	pio.overridden ? " (overriding vendor mode)" : "");

	program_cycle_times(drive, pio.cycle_time,
	ide_pio_timings[pio_mode].active_time);

	setup_count = quantize_timing(ide_pio_timings[pio_mode].setup_time,
	1000 / system_bus_clock());

	/*
	* The primary channel has individual address setup timing registers
	* for each drive and the hardware selects the slowest timing itself.
	* The secondary channel has one common register and we have to select
	* the slowest address setup timing ourselves.
	*/
	if (hwif->channel) {
	ide_drive_t *drives = hwif->drives;

	drive->drive_data = setup_count;
	setup_count = max(drives[0].drive_data, drives[1].drive_data);
	}

	if (setup_count > 5) /* shouldn't actually happen... */
	setup_count = 5;
	cmdprintk("Final address setup count: %d\n", setup_count);

	/*
	* Program the address setup clocks into the ARTTIM registers.
	* Avoid clearing the secondary channel's interrupt bit.
	*/
	(void) pci_read_config_byte (dev, arttim_regs[drive->dn], &arttim);
	if (hwif->channel)
	arttim &= ~ARTTIM23_INTR_CH1;
	arttim &= ~0xc0;
	arttim \|= setup_values[setup_count];
	(void) pci_write_config_byte(dev, arttim_regs[drive->dn], arttim);
	cmdprintk("Write 0x%02x to reg 0x%x\n", arttim, arttim_regs[drive->dn]);

	return pio_mode;
	}

	/*
	* Attempts to set drive's PIO mode.
	* Special cases are 8: prefetch off, 9: prefetch on (both never worked),
	* and 255: auto-select best mode (used at boot time).
	*/
	static void cmd64x_tune_drive (ide_drive_t *drive, u8 pio)
	{
	/*
	* Filter out the prefetch control values
	* to prevent PIO5 from being programmed
	*/
	if (pio == 8 \|\| pio == 9)
	return;

	pio = cmd64x_tune_pio(drive, pio);
	(void) ide_config_drive_speed(drive, XFER_PIO_0 + pio);
	}

	static int cmd64x_tune_chipset (ide_drive_t *drive, u8 speed)
	{
	ide_hwif_t *hwif = HWIF(drive);
	struct pci_dev *dev = hwif->pci_dev;
	u8 unit = drive->dn & 0x01;
	u8 regU = 0, pciU = hwif->channel ? UDIDETCR1 : UDIDETCR0;

	speed = ide_rate_filter(drive, speed);

	if (speed >= XFER_SW_DMA_0) {
	(void) pci_read_config_byte(dev, pciU, &regU);
	regU &= ~(unit ? 0xCA : 0x35);
	}

	switch(speed) {
	case XFER_UDMA_5:
	regU \|= unit ? 0x0A : 0x05;
	break;
	case XFER_UDMA_4:
	regU \|= unit ? 0x4A : 0x15;
	break;
	case XFER_UDMA_3:
	regU \|= unit ? 0x8A : 0x25;
	break;
	case XFER_UDMA_2:
	regU \|= unit ? 0x42 : 0x11;
	break;
	case XFER_UDMA_1:
	regU \|= unit ? 0x82 : 0x21;
	break;
	case XFER_UDMA_0:
	regU \|= unit ? 0xC2 : 0x31;
	break;
	case XFER_MW_DMA_2:
	program_cycle_times(drive, 120, 70);
	break;
	case XFER_MW_DMA_1:
	program_cycle_times(drive, 150, 80);
	break;
	case XFER_MW_DMA_0:
	program_cycle_times(drive, 480, 215);
	break;
	case XFER_PIO_5:
	case XFER_PIO_4:
	case XFER_PIO_3:
	case XFER_PIO_2:
	case XFER_PIO_1:
	case XFER_PIO_0:
	(void) cmd64x_tune_pio(drive, speed - XFER_PIO_0);
	break;
	default:
	return 1;
	}

	if (speed >= XFER_SW_DMA_0)
	(void) pci_write_config_byte(dev, pciU, regU);

	return ide_config_drive_speed(drive, speed);
	}

	static int cmd64x_config_drive_for_dma (ide_drive_t *drive)
	{
	if (ide_tune_dma(drive))
	return 0;

	if (ide_use_fast_pio(drive))
	cmd64x_tune_drive(drive, 255);

	return -1;
	}

	static int cmd648_ide_dma_end (ide_drive_t *drive)
	{
	ide_hwif_t *hwif = HWIF(drive);
	int err = __ide_dma_end(drive);
	u8 irq_mask = hwif->channel ? MRDMODE_INTR_CH1 :
	MRDMODE_INTR_CH0;
	u8 mrdmode = inb(hwif->dma_master + 0x01);

	/* clear the interrupt bit */
	outb(mrdmode \| irq_mask, hwif->dma_master + 0x01);

	return err;
	}

	static int cmd64x_ide_dma_end (ide_drive_t *drive)
	{
	ide_hwif_t *hwif = HWIF(drive);
	struct pci_dev *dev = hwif->pci_dev;
	int irq_reg = hwif->channel ? ARTTIM23 : CFR;
	u8 irq_mask = hwif->channel ? ARTTIM23_INTR_CH1 :
	CFR_INTR_CH0;
	u8 irq_stat = 0;
	int err = __ide_dma_end(drive);

	(void) pci_read_config_byte(dev, irq_reg, &irq_stat);
	/* clear the interrupt bit */
	(void) pci_write_config_byte(dev, irq_reg, irq_stat \| irq_mask);

	return err;
	}

	static int cmd648_ide_dma_test_irq (ide_drive_t *drive)
	{
	ide_hwif_t *hwif = HWIF(drive);
	u8 irq_mask = hwif->channel ? MRDMODE_INTR_CH1 :
	MRDMODE_INTR_CH0;
	u8 dma_stat = inb(hwif->dma_status);
	u8 mrdmode = inb(hwif->dma_master + 0x01);

	#ifdef DEBUG
	printk("%s: dma_stat: 0x%02x mrdmode: 0x%02x irq_mask: 0x%02x\n",
	drive->name, dma_stat, mrdmode, irq_mask);
	#endif
	if (!(mrdmode & irq_mask))
	return 0;

	/* return 1 if INTR asserted */
	if (dma_stat & 4)
	return 1;

	return 0;
	}

	static int cmd64x_ide_dma_test_irq (ide_drive_t *drive)
	{
	ide_hwif_t *hwif = HWIF(drive);
	struct pci_dev *dev = hwif->pci_dev;
	int irq_reg = hwif->channel ? ARTTIM23 : CFR;
	u8 irq_mask = hwif->channel ? ARTTIM23_INTR_CH1 :
	CFR_INTR_CH0;
	u8 dma_stat = inb(hwif->dma_status);
	u8 irq_stat = 0;

	(void) pci_read_config_byte(dev, irq_reg, &irq_stat);

	#ifdef DEBUG
	printk("%s: dma_stat: 0x%02x irq_stat: 0x%02x irq_mask: 0x%02x\n",
	drive->name, dma_stat, irq_stat, irq_mask);
	#endif
	if (!(irq_stat & irq_mask))
	return 0;

	/* return 1 if INTR asserted */
	if (dma_stat & 4)
	return 1;

	return 0;
	}

	/*
	* ASUS P55T2P4D with CMD646 chipset revision 0x01 requires the old
	* event order for DMA transfers.
	*/

	static int cmd646_1_ide_dma_end (ide_drive_t *drive)
	{
	ide_hwif_t *hwif = HWIF(drive);
	u8 dma_stat = 0, dma_cmd = 0;

	drive->waiting_for_dma = 0;
	/* get DMA status */
	dma_stat = inb(hwif->dma_status);
	/* read DMA command state */
	dma_cmd = inb(hwif->dma_command);
	/* stop DMA */
	outb(dma_cmd & ~1, hwif->dma_command);
	/* clear the INTR & ERROR bits */
	outb(dma_stat \| 6, hwif->dma_status);
	/* and free any DMA resources */
	ide_destroy_dmatable(drive);
	/* verify good DMA status */
	return (dma_stat & 7) != 4;
	}

	static unsigned int __devinit init_chipset_cmd64x(struct pci_dev dev, const char name)
	{
	u32 class_rev = 0;
	u8 mrdmode = 0;

	pci_read_config_dword(dev, PCI_CLASS_REVISION, &class_rev);
	class_rev &= 0xff;

	switch(dev->device) {
	case PCI_DEVICE_ID_CMD_643:
	break;
	case PCI_DEVICE_ID_CMD_646:
	printk(KERN_INFO "%s: chipset revision 0x%02X, ", name, class_rev);
	switch(class_rev) {
	case 0x07:
	case 0x05:
	printk("UltraDMA Capable");
	break;
	case 0x03:
	printk("MultiWord DMA Force Limited");
	break;
	case 0x01:
	default:
	printk("MultiWord DMA Limited, IRQ workaround enabled");
	break;
	}
	printk("\n");
	break;
	case PCI_DEVICE_ID_CMD_648:
	case PCI_DEVICE_ID_CMD_649:
	break;
	default:
	break;
	}

	/* Set a good latency timer and cache line size value. */
	(void) pci_write_config_byte(dev, PCI_LATENCY_TIMER, 64);
	/* FIXME: pci_set_master() to ensure a good latency timer value */

	/* Setup interrupts. */
	(void) pci_read_config_byte(dev, MRDMODE, &mrdmode);
	mrdmode &= ~(0x30);
	(void) pci_write_config_byte(dev, MRDMODE, mrdmode);

	/* Use MEMORY READ LINE for reads.
	* NOTE: Although not mentioned in the PCI0646U specs,
	* these bits are write only and won't be read
	* back as set or not. The PCI0646U2 specs clarify
	* this point.
	*/
	(void) pci_write_config_byte(dev, MRDMODE, mrdmode \| 0x02);

	/* Set reasonable active/recovery/address-setup values. */
	(void) pci_write_config_byte(dev, ARTTIM0, 0x40);
	(void) pci_write_config_byte(dev, DRWTIM0, 0x3f);
	(void) pci_write_config_byte(dev, ARTTIM1, 0x40);
	(void) pci_write_config_byte(dev, DRWTIM1, 0x3f);
	#ifdef __i386__
	(void) pci_write_config_byte(dev, ARTTIM23, 0x1c);
	#else
	(void) pci_write_config_byte(dev, ARTTIM23, 0x5c);
	#endif
	(void) pci_write_config_byte(dev, DRWTIM23, 0x3f);
	(void) pci_write_config_byte(dev, DRWTIM3, 0x3f);
	#ifdef CONFIG_PPC
	(void) pci_write_config_byte(dev, UDIDETCR0, 0xf0);
	#endif /* CONFIG_PPC */

	#if defined(DISPLAY_CMD64X_TIMINGS) && defined(CONFIG_IDE_PROC_FS)

	cmd_devs[n_cmd_devs++] = dev;

	if (!cmd64x_proc) {
	cmd64x_proc = 1;
	ide_pci_create_host_proc("cmd64x", cmd64x_get_info);
	}
	#endif /* DISPLAY_CMD64X_TIMINGS && CONFIG_IDE_PROC_FS */

	return 0;
	}

	static unsigned int __devinit ata66_cmd64x(ide_hwif_t *hwif)
	{
	u8 ata66 = 0, mask = (hwif->channel) ? 0x02 : 0x01;

	switch(hwif->pci_dev->device) {
	case PCI_DEVICE_ID_CMD_643:
	case PCI_DEVICE_ID_CMD_646:
	return ata66;
	default:
	break;
	}
	pci_read_config_byte(hwif->pci_dev, BMIDECSR, &ata66);
	return (ata66 & mask) ? 1 : 0;
	}

	static void __devinit init_hwif_cmd64x(ide_hwif_t *hwif)
	{
	struct pci_dev *dev = hwif->pci_dev;
	unsigned int class_rev;

	hwif->autodma = 0;
	pci_read_config_dword(dev, PCI_CLASS_REVISION, &class_rev);
	class_rev &= 0xff;

	hwif->tuneproc = &cmd64x_tune_drive;
	hwif->speedproc = &cmd64x_tune_chipset;

	hwif->drives[0].autotune = hwif->drives[1].autotune = 1;

	if (!hwif->dma_base)
	return;

	hwif->atapi_dma = 1;

	hwif->ultra_mask = hwif->cds->udma_mask;

	/*
	* UltraDMA only supported on PCI646U and PCI646U2, which
	* correspond to revisions 0x03, 0x05 and 0x07 respectively.
	* Actually, although the CMD tech support people won't
	* tell me the details, the 0x03 revision cannot support
	* UDMA correctly without hardware modifications, and even
	* then it only works with Quantum disks due to some
	* hold time assumptions in the 646U part which are fixed
	* in the 646U2.
	*
	* So we only do UltraDMA on revision 0x05 and 0x07 chipsets.
	*/
	if (dev->device == PCI_DEVICE_ID_CMD_646 && class_rev < 5)
	hwif->ultra_mask = 0x00;

	hwif->mwdma_mask = 0x07;

	hwif->ide_dma_check = &cmd64x_config_drive_for_dma;
	if (!(hwif->udma_four))
	hwif->udma_four = ata66_cmd64x(hwif);

	switch(dev->device) {
	case PCI_DEVICE_ID_CMD_648:
	case PCI_DEVICE_ID_CMD_649:
	alt_irq_bits:
	hwif->ide_dma_end = &cmd648_ide_dma_end;
	hwif->ide_dma_test_irq = &cmd648_ide_dma_test_irq;
	break;
	case PCI_DEVICE_ID_CMD_646:
	hwif->chipset = ide_cmd646;
	if (class_rev == 0x01) {
	hwif->ide_dma_end = &cmd646_1_ide_dma_end;
	break;
	} else if (class_rev >= 0x03)
	goto alt_irq_bits;
	/* fall thru */
	default:
	hwif->ide_dma_end = &cmd64x_ide_dma_end;
	hwif->ide_dma_test_irq = &cmd64x_ide_dma_test_irq;
	break;
	}


	if (!noautodma)
	hwif->autodma = 1;
	hwif->drives[0].autodma = hwif->autodma;
	hwif->drives[1].autodma = hwif->autodma;
	}

	static int __devinit init_setup_cmd64x(struct pci_dev dev, ide_pci_device_t d)
	{
	return ide_setup_pci_device(dev, d);
	}

	static int __devinit init_setup_cmd646(struct pci_dev dev, ide_pci_device_t d)
	{
	u8 rev = 0;

	/*
	* The original PCI0646 didn't have the primary channel enable bit,
	* it appeared starting with PCI0646U (i.e. revision ID 3).
	*/
	pci_read_config_byte(dev, PCI_REVISION_ID, &rev);
	if (rev < 3)
	d->enablebits[0].reg = 0;

	return ide_setup_pci_device(dev, d);
	}

	static ide_pci_device_t cmd64x_chipsets[] __devinitdata = {
	{ /* 0 */
	.name = "CMD643",
	.init_setup = init_setup_cmd64x,
	.init_chipset = init_chipset_cmd64x,
	.init_hwif = init_hwif_cmd64x,
	.channels = 2,
	.autodma = AUTODMA,
	.enablebits = {{0x00,0x00,0x00}, {0x51,0x08,0x08}},
	.bootable = ON_BOARD,
	.udma_mask = 0x00, /* no udma */
	},{ /* 1 */
	.name = "CMD646",
	.init_setup = init_setup_cmd646,
	.init_chipset = init_chipset_cmd64x,
	.init_hwif = init_hwif_cmd64x,
	.channels = 2,
	.autodma = AUTODMA,
	.enablebits = {{0x51,0x04,0x04}, {0x51,0x08,0x08}},
	.bootable = ON_BOARD,
	.udma_mask = 0x07, /* udma0-2 */
	},{ /* 2 */
	.name = "CMD648",
	.init_setup = init_setup_cmd64x,
	.init_chipset = init_chipset_cmd64x,
	.init_hwif = init_hwif_cmd64x,
	.channels = 2,
	.autodma = AUTODMA,
	.enablebits = {{0x51,0x04,0x04}, {0x51,0x08,0x08}},
	.bootable = ON_BOARD,
	.udma_mask = 0x1f, /* udma0-4 */
	},{ /* 3 */
	.name = "CMD649",
	.init_setup = init_setup_cmd64x,
	.init_chipset = init_chipset_cmd64x,
	.init_hwif = init_hwif_cmd64x,
	.channels = 2,
	.autodma = AUTODMA,
	.enablebits = {{0x51,0x04,0x04}, {0x51,0x08,0x08}},
	.bootable = ON_BOARD,
	.udma_mask = 0x3f, /* udma0-5 */
	}
	};

	/*
	* We may have to modify enablebits for PCI0646, so we'd better pass
	* a local copy of the ide_pci_device_t structure down the call chain...
	*/
	static int __devinit cmd64x_init_one(struct pci_dev dev, const struct pci_device_id id)
	{
	ide_pci_device_t d = cmd64x_chipsets[id->driver_data];

	return d.init_setup(dev, &d);
	}

	static struct pci_device_id cmd64x_pci_tbl[] = {
	{ PCI_VENDOR_ID_CMD, PCI_DEVICE_ID_CMD_643, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
	{ PCI_VENDOR_ID_CMD, PCI_DEVICE_ID_CMD_646, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 1},
	{ PCI_VENDOR_ID_CMD, PCI_DEVICE_ID_CMD_648, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 2},
	{ PCI_VENDOR_ID_CMD, PCI_DEVICE_ID_CMD_649, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 3},
	{ 0, },
	};
	MODULE_DEVICE_TABLE(pci, cmd64x_pci_tbl);

	static struct pci_driver driver = {
	.name = "CMD64x_IDE",
	.id_table = cmd64x_pci_tbl,
	.probe = cmd64x_init_one,
	};

	static int __init cmd64x_ide_init(void)
	{
	return ide_pci_register_driver(&driver);
	}

	module_init(cmd64x_ide_init);

	MODULE_AUTHOR("Eddie Dost, David Miller, Andre Hedrick");
	MODULE_DESCRIPTION("PCI driver module for CMD64x IDE");
	MODULE_LICENSE("GPL");