via82cxxx.c

ep9315平台下硬盘驱动的源码

	T = 1000000000 / via_clock;

	switch (via_config->flags & VIA_UDMA) {
		case VIA_UDMA_33:   UT = T;   break;
		case VIA_UDMA_66:   UT = T/2; break;
		case VIA_UDMA_100:  UT = T/3; break;
		case VIA_UDMA_133:  UT = T/4; break;
		default: UT = T;
	}

	ide_timing_compute(drive, speed, &t, T, UT);

	if (peer->present) {
		ide_timing_compute(peer, peer->current_speed, &p, T, UT);
		ide_timing_merge(&p, &t, &t, IDE_TIMING_8BIT);
	}

	via_set_speed(HWIF(drive)->pci_dev, drive->dn, &t);

	if (!drive->init_speed)
		drive->init_speed = speed;
	drive->current_speed = speed;

	return 0;
}

/**
 *	via82cxxx_tune_drive	-	PIO setup
 *	@drive: drive to set up
 *	@pio: mode to use (255 for 'best possible')
 *
 *	A callback from the upper layers for PIO-only tuning.
 */

static void via82cxxx_tune_drive(ide_drive_t *drive, u8 pio)
{
	if (!((via_enabled >> HWIF(drive)->channel) & 1))
		return;

	if (pio == 255) {
		via_set_drive(drive,
			ide_find_best_mode(drive, XFER_PIO | XFER_EPIO));
		return;
	}

	via_set_drive(drive, XFER_PIO_0 + MIN(pio, 5));
}

/**
 *	via82cxxx_ide_dma_check		-	set up for DMA if possible
 *	@drive: IDE drive to set up
 *
 *	Set up the drive for the highest supported speed considering the
 *	driver, controller and cable
 */
 
static int via82cxxx_ide_dma_check (ide_drive_t *drive)
{
	u16 w80 = HWIF(drive)->udma_four;

	u16 speed = ide_find_best_mode(drive,
		XFER_PIO | XFER_EPIO | XFER_SWDMA | XFER_MWDMA |
		(via_config->flags & VIA_UDMA ? XFER_UDMA : 0) |
		(w80 && (via_config->flags & VIA_UDMA) >= VIA_UDMA_66 ? XFER_UDMA_66 : 0) |
		(w80 && (via_config->flags & VIA_UDMA) >= VIA_UDMA_100 ? XFER_UDMA_100 : 0) |
		(w80 && (via_config->flags & VIA_UDMA) >= VIA_UDMA_133 ? XFER_UDMA_133 : 0));

	via_set_drive(drive, speed);

	if (drive->autodma && (speed & XFER_MODE) != XFER_PIO)
		return HWIF(drive)->ide_dma_on(drive);
	return HWIF(drive)->ide_dma_off_quietly(drive);
}

/**
 *	init_chipset_via82cxxx	-	initialization handler
 *	@dev: PCI device
 *	@name: Name of interface
 *
 *	The initialization callback. Here we determine the IDE chip type
 *	and initialize its drive independent registers.
 */

static unsigned int __init init_chipset_via82cxxx(struct pci_dev *dev, const char *name)
{
	struct pci_dev *isa = NULL;
	u8 t, v;
	unsigned int u;
	int i;

	/*
	 * Find the ISA bridge to see how good the IDE is.
	 */

	for (via_config = via_isa_bridges; via_config->id; via_config++)
		if ((isa = pci_find_device(PCI_VENDOR_ID_VIA +
			!!(via_config->flags & VIA_BAD_ID),
			via_config->id, NULL))) {

			pci_read_config_byte(isa, PCI_REVISION_ID, &t);
			if (t >= via_config->rev_min &&
			    t <= via_config->rev_max)
				break;
		}

	if (!via_config->id) {
		printk(KERN_WARNING "VP_IDE: Unknown VIA SouthBridge, disabling DMA.\n");
		return -ENODEV;
	}

	/*
	 * Check 80-wire cable presence and setup Clk66.
	 */

	switch (via_config->flags & VIA_UDMA) {

		case VIA_UDMA_66:
			/* Enable Clk66 */
			pci_read_config_dword(dev, VIA_UDMA_TIMING, &u);
			pci_write_config_dword(dev, VIA_UDMA_TIMING, u|0x80008);
			for (i = 24; i >= 0; i -= 8)
				if (((u >> (i & 16)) & 8) &&
				    ((u >> i) & 0x20) &&
				     (((u >> i) & 7) < 2)) {
					/*
					 * 2x PCI clock and
					 * UDMA w/ < 3T/cycle
					 */
					via_80w |= (1 << (1 - (i >> 4)));
				}
			break;

		case VIA_UDMA_100:
			pci_read_config_dword(dev, VIA_UDMA_TIMING, &u);
			for (i = 24; i >= 0; i -= 8)
				if (((u >> i) & 0x10) ||
				    (((u >> i) & 0x20) &&
				     (((u >> i) & 7) < 4))) {
					/* BIOS 80-wire bit or
					 * UDMA w/ < 60ns/cycle
					 */
					via_80w |= (1 << (1 - (i >> 4)));
				}
			break;

		case VIA_UDMA_133:
			pci_read_config_dword(dev, VIA_UDMA_TIMING, &u);
			for (i = 24; i >= 0; i -= 8)
				if (((u >> i) & 0x10) ||
				    (((u >> i) & 0x20) &&
				     (((u >> i) & 7) < 8))) {
					/* BIOS 80-wire bit or
					 * UDMA w/ < 60ns/cycle
					 */
					via_80w |= (1 << (1 - (i >> 4)));
				}
			break;

	}

	/* Disable Clk66 */
	if (via_config->flags & VIA_BAD_CLK66) {
		/* Would cause trouble on 596a and 686 */
		pci_read_config_dword(dev, VIA_UDMA_TIMING, &u);
		pci_write_config_dword(dev, VIA_UDMA_TIMING, u & ~0x80008);
	}

	/*
	 * Check whether interfaces are enabled.
	 */

	pci_read_config_byte(dev, VIA_IDE_ENABLE, &v);
	via_enabled = ((v & 1) ? 2 : 0) | ((v & 2) ? 1 : 0);

	/*
	 * Set up FIFO sizes and thresholds.
	 */

	pci_read_config_byte(dev, VIA_FIFO_CONFIG, &t);

	/* Disable PREQ# till DDACK# */
	if (via_config->flags & VIA_BAD_PREQ) {
		/* Would crash on 586b rev 41 */
		t &= 0x7f;
	}

	/* Fix FIFO split between channels */
	if (via_config->flags & VIA_SET_FIFO) {
		t &= (t & 0x9f);
		switch (via_enabled) {
			case 1: t |= 0x00; break;	/* 16 on primary */
			case 2: t |= 0x60; break;	/* 16 on secondary */
			case 3: t |= 0x20; break;	/* 8 pri 8 sec */
		}
	}

	pci_write_config_byte(dev, VIA_FIFO_CONFIG, t);

	/*
	 * Determine system bus clock.
	 */

	via_clock = system_bus_clock() * 1000;

	switch (via_clock) {
		case 33000: via_clock = 33333; break;
		case 37000: via_clock = 37500; break;
		case 41000: via_clock = 41666; break;
	}

	if (via_clock < 20000 || via_clock > 50000) {
		printk(KERN_WARNING "VP_IDE: User given PCI clock speed "
			"impossible (%d), using 33 MHz instead.\n", via_clock);
		printk(KERN_WARNING "VP_IDE: Use ide0=ata66 if you want "
			"to assume 80-wire cable.\n");
		via_clock = 33333;
	}

	/*
	 * Print the boot message.
	 */

	pci_read_config_byte(isa, PCI_REVISION_ID, &t);
	printk(KERN_INFO "VP_IDE: VIA %s (rev %02x) IDE %s "
		"controller on pci%s\n",
		via_config->name, t,
		via_dma[via_config->flags & VIA_UDMA],
		dev->slot_name);

	/*
	 * Setup /proc/ide/via entry.
	 */

#if defined(DISPLAY_VIA_TIMINGS) && defined(CONFIG_PROC_FS)
	if (!via_proc) {
		via_base = pci_resource_start(dev, 4);
		bmide_dev = dev;
		isa_dev = isa;
		ide_pci_register_host_proc(&via_procs[0]);
		via_proc = 1;
	}
#endif /* DISPLAY_VIA_TIMINGS && CONFIG_PROC_FS */
	return 0;
}

static void __init init_hwif_via82cxxx(ide_hwif_t *hwif)
{
	int i;

	hwif->autodma = 0;

	hwif->tuneproc = &via82cxxx_tune_drive;
	hwif->speedproc = &via_set_drive;

	for (i = 0; i < 2; i++) {
		hwif->drives[i].io_32bit = 1;
		hwif->drives[i].unmask = (via_config->flags & VIA_NO_UNMASK) ? 0 : 1;
		hwif->drives[i].autotune = 1;
		hwif->drives[i].dn = hwif->channel * 2 + i;
	}

	if (!hwif->dma_base)
		return;

	hwif->atapi_dma = 1;
	hwif->ultra_mask = 0x7f;
	hwif->mwdma_mask = 0x07;
	hwif->swdma_mask = 0x07;

	if (!(hwif->udma_four))
		hwif->udma_four = ((via_enabled & via_80w) >> hwif->channel) & 1;
	hwif->ide_dma_check = &via82cxxx_ide_dma_check;
	if (!noautodma)
		hwif->autodma = 1;
	hwif->drives[0].autodma = hwif->autodma;
	hwif->drives[1].autodma = hwif->autodma;
}

/**
 *	init_dma_via82cxxx	-	set up for IDE DMA
 *	@hwif: IDE interface
 *	@dmabase: DMA base address
 *
 *	We allow the BM-DMA driver to only work on enabled interfaces.
 */

static void __init init_dma_via82cxxx(ide_hwif_t *hwif, unsigned long dmabase)
{
	if ((via_enabled >> hwif->channel) & 1)
		ide_setup_dma(hwif, dmabase, 8);
}

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

static int __devinit via_init_one(struct pci_dev *dev, const struct pci_device_id *id)
{
	ide_pci_device_t *d = &via82cxxx_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 via_pci_tbl[] __devinitdata = {
	{ PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C576_1, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
	{ PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C586_1, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 1},
	{ 0, },
};

static struct pci_driver driver = {
	.name 		= "VIA IDE",
	.id_table 	= via_pci_tbl,
	.probe 		= via_init_one,
};

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

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

module_init(via_ide_init);
module_exit(via_ide_exit);

MODULE_AUTHOR("Vojtech Pavlik, Michel Aubry, Jeff Garzik, Andre Hedrick");
MODULE_DESCRIPTION("PCI driver module for VIA IDE");
MODULE_LICENSE("GPL");

EXPORT_NO_SYMBOLS;