/*
* PCI operations for the Sega Dreamcast
*
* Copyright (C) 2001, 2002 M. R. Brown
* Copyright (C) 2002, 2003 Paul Mundt
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/param.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/pci.h>
#include <linux/module.h>
#include <linux/io.h>
#include <mach/pci.h>
/*
* The !gapspci_config_access case really shouldn't happen, ever, unless
* someone implicitly messes around with the last devfn value.. otherwise we
* only support a single device anyways, and if we didn't have a BBA, we
* wouldn't make it terribly far through the PCI setup anyways.
*
* Also, we could very easily support both Type 0 and Type 1 configurations
* here, but since it doesn't seem that there is any such implementation in
* existence, we don't bother.
*
* I suppose if someone actually gets around to ripping the chip out of
* the BBA and hanging some more devices off of it, then this might be
* something to take into consideration. However, due to the cost of the BBA,
* and the general lack of activity by DC hardware hackers, this doesn't seem
* likely to happen anytime soon.
*/
static int gapspci_config_access(unsigned char bus, unsigned int devfn)
{
return (bus == 0) && (devfn == 0);
}
/*
* We can also actually read and write in b/w/l sizes! Thankfully this part
* was at least done right, and we don't have to do the stupid masking and
* shifting that we do on the 7751! Small wonders never cease to amaze.
*/
static int gapspci_read(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *val)
{
*val = 0xffffffff;
if (!gapspci_config_access(bus->number, devfn))
return PCIBIOS_DEVICE_NOT_FOUND;
switch (size) {
case 1: *val = inb(GAPSPCI_BBA_CONFIG+where); break;
case 2: *val = inw(GAPSPCI_BBA_CONFIG+where); break;
case 4: *val = inl(GAPSPCI_BBA_CONFIG+where); break;
}
return PCIBIOS_SUCCESSFUL;
}
static int gapspci_write(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 val)
{
if (!gapspci_config_access(bus->number, devfn))
return PCIBIOS_DEVICE_NOT_FOUND;
switch (size) {
case 1: outb(( u8)val, GAPSPCI_BBA_CONFIG+where); break;
case 2: outw((u16)val, GAPSPCI_BBA_CONFIG+where); break;
case 4: outl((u32)val, GAPSPCI_BBA_CONFIG+where); break;
}
return PCIBIOS_SUCCESSFUL;
}
struct pci_ops gapspci_pci_ops = {
.read = gapspci_read,
.write = gapspci_write,
};
