/*
 * linux/drivers/ide/sl82c105.c
 *
 * SL82C105/Winbond 553 IDE driver
 *
 * Maintainer unknown.
 *
 * Drive tuning added from Rebel.com's kernel sources
 *  -- Russell King (15/11/98) linux@arm.linux.org.uk
 */

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

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

#include "ide_modes.h"
#include "sl82c105.h"

/*
 * Convert a PIO mode and cycle time to the required on/off
 * times for the interface.  This has protection against run-away
 * timings.
 */
static unsigned int get_timing_sl82c105(ide_pio_data_t *p)
{
	unsigned int cmd_on;
	unsigned int cmd_off;

	cmd_on = (ide_pio_timings[p->pio_mode].active_time + 29) / 30;
	cmd_off = (p->cycle_time - 30 * cmd_on + 29) / 30;

	if (cmd_on > 32)
		cmd_on = 32;
	if (cmd_on == 0)
		cmd_on = 1;

	if (cmd_off > 32)
		cmd_off = 32;
	if (cmd_off == 0)
		cmd_off = 1;

	return (cmd_on - 1) << 8 | (cmd_off - 1) | (p->use_iordy ? 0x40 : 0x00);
}

/*
 * Configure the drive and chipset for PIO
 */
static void config_for_pio(ide_drive_t *drive, int pio, int report)
{
	ide_hwif_t *hwif = HWIF(drive);
	struct pci_dev *dev = hwif->pci_dev;
	ide_pio_data_t p;
	u16 drv_ctrl = 0x909;
	unsigned int xfer_mode, reg;

	reg = (hwif->channel ? 0x4c : 0x44) + (drive->select.b.unit ? 4 : 0);

	pio = ide_get_best_pio_mode(drive, pio, 5, &p);

	xfer_mode = XFER_PIO_0 + pio;

	if (ide_config_drive_speed(drive, xfer_mode) == 0)
		drv_ctrl = get_timing_sl82c105(&p);

	if (drive->using_dma == 0) {
		/*
		 * If we are actually using MW DMA, then we can not
		 * reprogram the interface drive control register.
		 */
		pci_write_config_word(dev, reg, drv_ctrl);
		pci_read_config_word(dev, reg, &drv_ctrl);

		if (report) {
			printk("%s: selected %s (%dns) (%04X)\n", drive->name,
			       ide_xfer_verbose(xfer_mode), p.cycle_time, drv_ctrl);
		}
	}
}

/*
 * Configure the drive and the chipset for DMA
 */
static int config_for_dma (ide_drive_t *drive)
{
	ide_hwif_t *hwif = HWIF(drive);
	struct pci_dev *dev = hwif->pci_dev;
	u16 drv_ctrl = 0x909;
	unsigned int reg;

	reg = (hwif->channel ? 0x4c : 0x44) + (drive->select.b.unit ? 4 : 0);

	if (ide_config_drive_speed(drive, XFER_MW_DMA_2) == 0)
		drv_ctrl = 0x0240;

	pci_write_config_word(dev, reg, drv_ctrl);

	return 0;
}

/*
 * Check to see if the drive and
 * chipset is capable of DMA mode
 */

static int sl82c105_check_drive (ide_drive_t *drive)
{
	ide_hwif_t *hwif	= HWIF(drive);
	do {
		struct hd_driveid *id = drive->id;

		if (!drive->autodma)
			break;

		if (!id || !(id->capability & 1))
			break;

		/* Consult the list of known "bad" drives */
		if (hwif->ide_dma_bad_drive(drive))
			break;

		if (id->field_valid & 2) {
			if ((id->dma_mword & hwif->mwdma_mask) ||
			    (id->dma_1word & hwif->swdma_mask))
				return hwif->ide_dma_on(drive);
		}

		if (hwif->ide_dma_good_drive(drive))
			return hwif->ide_dma_on(drive);
	} while (0);

	return hwif->ide_dma_off_quietly(drive);
}

static int sl82c105_ide_dma_on (ide_drive_t *drive)
{
	if (config_for_dma(drive)) {
		config_for_pio(drive, 4, 0);
		return HWIF(drive)->ide_dma_off_quietly(drive);
	}
	return __ide_dma_on(drive);
}

static int sl82c105_ide_dma_off (ide_drive_t *drive)
{
	config_for_pio(drive, 4, 0);
	return __ide_dma_off(drive);
}

static int sl82c105_ide_dma_off_quietly (ide_drive_t *drive)
{
	config_for_pio(drive, 4, 0);
	return __ide_dma_off_quietly(drive);
}

/*
 * We only deal with PIO mode here - DMA mode 'using_dma' is not
 * initialised at the point that this function is called.
 */
static void tune_sl82c105(ide_drive_t *drive, u8 pio)
{
	config_for_pio(drive, pio, 1);

	/*
	 * We support 32-bit I/O on this interface, and it
	 * doesn't have problems with interrupts.
	 */
	drive->io_32bit = 1;
	drive->unmask = 1;
}

/*
 * Return the revision of the Winbond bridge
 * which this function is part of.
 */
static unsigned int sl82c105_bridge_revision(struct pci_dev *dev)
{
	struct pci_dev *bridge;
	u8 rev;

	bridge = pci_find_device(PCI_VENDOR_ID_WINBOND, PCI_DEVICE_ID_WINBOND_83C553, NULL);

	/*
	 * If we are part of a Winbond 553
	 */
	if (!bridge || bridge->class >> 8 != PCI_CLASS_BRIDGE_ISA)
		return -1;

	if (bridge->bus != dev->bus ||
	    PCI_SLOT(bridge->devfn) != PCI_SLOT(dev->devfn))
		return -1;

	/*
	 * We need to find function 0's revision, not function 1
	 */
	pci_read_config_byte(bridge, PCI_REVISION_ID, &rev);

	return rev;
}

/*
 * Enable the PCI device
 */
static unsigned int __init init_chipset_sl82c105(struct pci_dev *dev, const char *msg)
{
	u8 ctrl_stat;

	/*
	 * Enable the ports
	 */
	pci_read_config_byte(dev, 0x40, &ctrl_stat);
	pci_write_config_byte(dev, 0x40, ctrl_stat | 0x33);

	return dev->irq;
}

static void __init init_dma_sl82c105(ide_hwif_t *hwif, unsigned long dma_base)
{
	unsigned int rev;
	u8 dma_state;

	hwif->autodma = 0;

	if (!dma_base)
		return;

	dma_state = hwif->INB(dma_base + 2);
	rev = sl82c105_bridge_revision(hwif->pci_dev);
	if (rev <= 5) {
		hwif->drives[0].autotune = 1;
		hwif->drives[1].autotune = 1;
		printk("    %s: Winbond 553 bridge revision %d, BM-DMA disabled\n",
		       hwif->name, rev);
		dma_state &= ~0x60;
	} else {
		dma_state |= 0x60;
		if (!noautodma)
			hwif->autodma = 1;
	}
	hwif->OUTB(dma_state, dma_base + 2);

	ide_setup_dma(hwif, dma_base, 8);
}

/*
 * Initialise the chip
 */

static void __init init_hwif_sl82c105(ide_hwif_t *hwif)
{
	hwif->tuneproc = tune_sl82c105;

	if (!hwif->dma_base)
		return;

	hwif->atapi_dma = 1;
	hwif->mwdma_mask = 0x07;
	hwif->swdma_mask = 0x07;

#ifdef CONFIG_BLK_DEV_IDEDMA
	hwif->ide_dma_check = &sl82c105_check_drive;
	hwif->ide_dma_on = &sl82c105_ide_dma_on;
	hwif->ide_dma_off = &sl82c105_ide_dma_off;
	hwif->ide_dma_off_quietly = &sl82c105_ide_dma_off_quietly;
	if (!noautodma)
		hwif->autodma = 1;
	hwif->drives[0].autodma = hwif->autodma;
	hwif->drives[1].autodma = hwif->autodma;
#endif /* CONFIG_BLK_DEV_IDEDMA */
}

extern void ide_setup_pci_device(struct pci_dev *, ide_pci_device_t *);

static int __devinit sl82c105_init_one(struct pci_dev *dev, const struct pci_device_id *id)
{
	ide_pci_device_t *d = &sl82c105_chipsets[id->driver_data];
	if (dev->device != d->device)
		BUG();
	ide_setup_pci_device(dev, d);
	MOD_INC_USE_COUNT;
	return 0;
}

static struct pci_device_id sl82c105_pci_tbl[] __devinitdata = {
	{ PCI_VENDOR_ID_WINBOND, PCI_DEVICE_ID_WINBOND_82C105, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
	{ 0, },
};

static struct pci_driver driver = {
	.name		= "W82C105 IDE",
	.id_table	= sl82c105_pci_tbl,
	.probe		= sl82c105_init_one,
};

static int sl82c105_ide_init(void)
{
	return ide_pci_register_driver(&driver);
}

static void sl82c105_ide_exit(void)
{
	ide_pci_unregister_driver(&driver);
}

module_init(sl82c105_ide_init);
module_exit(sl82c105_ide_exit);

MODULE_DESCRIPTION("PCI driver module for W82C105 IDE");
MODULE_LICENSE("GPL");

EXPORT_NO_SYMBOLS;
