path: root/arch/mips/pci/ops-tx4938.c

/*
 * Define the pci_ops for the Toshiba rbtx4938
 * Copyright (C) 2000-2001 Toshiba Corporation
 *
 * 2003-2005 (c) MontaVista Software, Inc. This file is licensed under the
 * terms of the GNU General Public License version 2. This program is
 * licensed "as is" without any warranty of any kind, whether express
 * or implied.
 *
 * Support for TX4938 in 2.6 - Manish Lachwani (mlachwani@mvista.com)
 */
#include <linux/types.h>
#include <linux/pci.h>
#include <linux/kernel.h>
#include <linux/init.h>

#include <asm/addrspace.h>
#include <asm/tx4938/rbtx4938.h>

/* initialize in setup */
struct resource pci_io_resource = {
	.name	= "pci IO space",
	.start	= 0,
	.end	= 0,
	.flags	= IORESOURCE_IO
};

/* initialize in setup */
struct resource pci_mem_resource = {
	.name	= "pci memory space",
	.start	= 0,
	.end	= 0,
	.flags	= IORESOURCE_MEM
};

struct resource tx4938_pcic1_pci_io_resource = {
       	.name	= "PCI1 IO",
       	.start	= 0,
       	.end	= 0,
       	.flags	= IORESOURCE_IO
};
struct resource tx4938_pcic1_pci_mem_resource = {
       	.name	= "PCI1 mem",
       	.start	= 0,
       	.end	= 0,
       	.flags	= IORESOURCE_MEM
};

static int mkaddr(int bus, int dev_fn, int where, int *flagsp)
{
	if (bus > 0) {
		/* Type 1 configuration */
		tx4938_pcicptr->g2pcfgadrs = ((bus & 0xff) << 0x10) |
		    ((dev_fn & 0xff) << 0x08) | (where & 0xfc) | 1;
	} else {
		if (dev_fn >= PCI_DEVFN(TX4938_PCIC_MAX_DEVNU, 0))
			return -1;

		/* Type 0 configuration */
		tx4938_pcicptr->g2pcfgadrs = ((bus & 0xff) << 0x10) |
		    ((dev_fn & 0xff) << 0x08) | (where & 0xfc);
	}
	/* clear M_ABORT and Disable M_ABORT Int. */
	tx4938_pcicptr->pcistatus =
	    (tx4938_pcicptr->pcistatus & 0x0000ffff) |
	    (PCI_STATUS_REC_MASTER_ABORT << 16);
	tx4938_pcicptr->pcimask &= ~PCI_STATUS_REC_MASTER_ABORT;

	return 0;
}

static int check_abort(int flags)
{
	int code = PCIBIOS_SUCCESSFUL;
	/* wait write cycle completion before checking error status */
	while (tx4938_pcicptr->pcicstatus & TX4938_PCIC_PCICSTATUS_IWB)
				;
	if (tx4938_pcicptr->pcistatus & (PCI_STATUS_REC_MASTER_ABORT << 16)) {
		tx4938_pcicptr->pcistatus =
		    (tx4938_pcicptr->
		     pcistatus & 0x0000ffff) | (PCI_STATUS_REC_MASTER_ABORT
						<< 16);
		tx4938_pcicptr->pcimask |= PCI_STATUS_REC_MASTER_ABORT;
		code = PCIBIOS_DEVICE_NOT_FOUND;
	}
	return code;
}

static int tx4938_pcibios_read_config(struct pci_bus *bus, unsigned int devfn,
					int where, int size, u32 * val)
{
	int flags, retval, dev, busno, func;

	dev = PCI_SLOT(devfn);
	func = PCI_FUNC(devfn);

	/* check if the bus is top-level */
	if (bus->parent != NULL)
		busno = bus->number;
	else {
		busno = 0;
	}

	if (mkaddr(busno, devfn, where, &flags))
		return -1;

	switch (size) {
	case 1:
		*val = *(volatile u8 *) ((ulong) & tx4938_pcicptr->g2pcfgdata |
#ifdef __BIG_ENDIAN
			      ((where & 3) ^ 3));
#else
			      (where & 3));
#endif
		break;
	case 2:
		*val = *(volatile u16 *) ((ulong) & tx4938_pcicptr->g2pcfgdata |
#ifdef __BIG_ENDIAN
				((where & 3) ^ 2));
#else
				(where & 3));
#endif
		break;
	case 4:
		*val = tx4938_pcicptr->g2pcfgdata;
		break;
	}

	retval = check_abort(flags);
	if (retval == PCIBIOS_DEVICE_NOT_FOUND)
		*val = 0xffffffff;

	return retval;
}

static int tx4938_pcibios_write_config(struct pci_bus *bus, unsigned int devfn, int where,
						int size, u32 val)
{
	int flags, dev, busno, func;

	busno = bus->number;
	dev = PCI_SLOT(devfn);
	func = PCI_FUNC(devfn);

	/* check if the bus is top-level */
	if (bus->parent != NULL) {
		busno = bus->number;
	} else {
		busno = 0;
	}

	if (mkaddr(busno, devfn, where, &flags))
		return -1;

	switch (size) {
	case 1:
		*(volatile u8 *) ((ulong) & tx4938_pcicptr->g2pcfgdata |
#ifdef __BIG_ENDIAN
			  ((where & 3) ^ 3)) = val;
#else
			  (where & 3)) = val;
#endif
		break;
	case 2:
		*(volatile u16 *) ((ulong) & tx4938_pcicptr->g2pcfgdata |
#ifdef __BIG_ENDIAN
			((where & 0x3) ^ 0x2)) = val;
#else
			(where & 3)) = val;
#endif
		break;
	case 4:
		tx4938_pcicptr->g2pcfgdata = val;
		break;
	}

	return check_abort(flags);
}

struct pci_ops tx4938_pci_ops = {
	tx4938_pcibios_read_config,
	tx4938_pcibios_write_config
};

struct pci_controller tx4938_pci_controller[] = {
	/* h/w only supports devices 0x00 to 0x14 */
	{
		.pci_ops        = &tx4938_pci_ops,
		.io_resource    = &pci_io_resource,
		.mem_resource   = &pci_mem_resource,
	},
	/* h/w only supports devices 0x00 to 0x14 */
	{
		.pci_ops        = &tx4938_pci_ops,
		.io_resource    = &tx4938_pcic1_pci_io_resource,
		.mem_resource   = &tx4938_pcic1_pci_mem_resource,
        }
};