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