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/***********************************************************************
* Copyright 2001 MontaVista Software Inc.
* Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
*
* arch/mips/ddb5xxx/common/pci.c
* Common PCI routines for DDB5xxx - as a matter of fact, meant for all
* MIPS machines.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
***********************************************************************
*/
/*
* This file contains common PCI routines meant to be shared for
* all MIPS machines.
*
* Strategies:
*
* . We rely on pci_auto.c file to assign PCI resources (MEM and IO)
* TODO: this shold be optional for some machines where they do have
* a real "pcibios" that does resource assignment.
*
* . We then use pci_scan_bus() to "discover" all the resources for
* later use by Linux.
*
* . We finally reply on a board supplied function, pcibios_fixup_irq(), to
* to assign the interrupts. We may use setup-irq.c under drivers/pci
* later.
*
* . Specifically, we will *NOT* use pci_assign_unassigned_resources(),
* because we assume all PCI devices should have the resources correctly
* assigned and recorded.
*
* Limitations:
*
* . We "collapse" all IO and MEM spaces in sub-buses under a top-level bus
* into a contiguous range.
*
* . In the case of Memory space, the rnage is 1:1 mapping with CPU physical
* address space.
*
* . In the case of IO space, it starts from 0, and the beginning address
* is mapped to KSEG0ADDR(mips_io_port) in the CPU physical address.
*
* . These are the current MIPS limitations (by ioremap, etc). In the
* future, we may remove them.
*
* Credits:
* Most of the code are derived from the pci routines from PPC and Alpha,
* which were mostly writtne by
* Cort Dougan, cort@fsmlabs.com
* Matt Porter, mporter@mvista.com
* Dave Rusling david.rusling@reo.mts.dec.com
* David Mosberger davidm@cs.arizona.edu
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/pci.h>
#include <asm/ddb5xxx/pci.h>
#include <asm/ddb5xxx/debug.h>
struct pci_fixup pcibios_fixups[] = { {0} };
extern int pciauto_assign_resources(int busno, struct pci_channel * hose);
void __init pcibios_init(void)
{
struct pci_channel *p;
struct pci_bus *bus;
int busno;
/* assign resources */
busno=0;
for (p= mips_pci_channels; p->pci_ops != NULL; p++) {
busno = pciauto_assign_resources(busno, p) + 1;
}
/* scan the buses */
busno = 0;
for (p= mips_pci_channels; p->pci_ops != NULL; p++) {
bus = pci_scan_bus(busno, p->pci_ops, p);
busno = bus->subordinate+1;
}
/* fixup irqs (board specific routines) */
pcibios_fixup_irqs();
/*
* should we do a fixup of ioport_resource and iomem_resource
* based on mips_pci_channels?
* Let us wait and see if this is a common need and whether there
* are exceptions. Until then, each board should adjust them
* perhaps in their setup() function.
*/
}
int pcibios_enable_device(struct pci_dev *dev)
{
/* pciauto_assign_resources() will enable all devices found */
return 0;
}
unsigned long __init
pci_bridge_check_io(struct pci_dev *bridge)
{
u16 io;
pci_read_config_word(bridge, PCI_IO_BASE, &io);
if (!io) {
pci_write_config_word(bridge, PCI_IO_BASE, 0xf0f0);
pci_read_config_word(bridge, PCI_IO_BASE, &io);
pci_write_config_word(bridge, PCI_IO_BASE, 0x0);
}
if (io)
return IORESOURCE_IO;
printk(KERN_WARNING "PCI: bridge %s does not support I/O forwarding!\n",
bridge->name);
return 0;
}
void __init pcibios_fixup_bus(struct pci_bus *bus)
{
/* Propogate hose info into the subordinate devices. */
struct pci_channel *hose = bus->sysdata;
struct pci_dev *dev = bus->self;
if (!dev) {
/* Root bus */
bus->resource[0] = hose->io_resource;
bus->resource[1] = hose->mem_resource;
} else {
/* This is a bridge. Do not care how it's initialized,
just link its resources to the bus ones */
int i;
for(i=0; i<3; i++) {
bus->resource[i] =
&dev->resource[PCI_BRIDGE_RESOURCES+i];
bus->resource[i]->name = bus->name;
}
bus->resource[0]->flags |= pci_bridge_check_io(dev);
bus->resource[1]->flags |= IORESOURCE_MEM;
/* For now, propogate hose limits to the bus;
we'll adjust them later. */
bus->resource[0]->end = hose->io_resource->end;
bus->resource[1]->end = hose->mem_resource->end;
/* Turn off downstream PF memory address range by default */
bus->resource[2]->start = 1024*1024;
bus->resource[2]->end = bus->resource[2]->start - 1;
}
}
char *pcibios_setup(char *str)
{
return str;
}
void
pcibios_align_resource(void *data, struct resource *res, unsigned long size)
{
/* this should not be called */
MIPS_ASSERT(1 == 0);
}
void
pcibios_update_resource(struct pci_dev *dev, struct resource *root,
struct resource *res, int resource)
{
/* this should not be called */
MIPS_ASSERT(1 == 0);
}
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