1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * PCI support for the Sega Dreamcast
4 *
5 * Copyright (C) 2001, 2002 M. R. Brown
6 * Copyright (C) 2002, 2003 Paul Mundt
7 *
8 * This file originally bore the message (with enclosed-$):
9 * Id: pci.c,v 1.3 2003/05/04 19:29:46 lethal Exp
10 * Dreamcast PCI: Supports SEGA Broadband Adaptor only.
11 */
12
13 #include <linux/sched.h>
14 #include <linux/kernel.h>
15 #include <linux/param.h>
16 #include <linux/interrupt.h>
17 #include <linux/init.h>
18 #include <linux/irq.h>
19 #include <linux/pci.h>
20 #include <linux/module.h>
21 #include <asm/io.h>
22 #include <asm/irq.h>
23 #include <mach/pci.h>
24
25 static struct resource gapspci_resources[] = {
26 {
27 .name = "GAPSPCI IO",
28 .start = GAPSPCI_BBA_CONFIG,
29 .end = GAPSPCI_BBA_CONFIG + GAPSPCI_BBA_CONFIG_SIZE - 1,
30 .flags = IORESOURCE_IO,
31 }, {
32 .name = "GAPSPCI mem",
33 .start = GAPSPCI_DMA_BASE,
34 .end = GAPSPCI_DMA_BASE + GAPSPCI_DMA_SIZE - 1,
35 .flags = IORESOURCE_MEM,
36 },
37 };
38
39 static struct pci_channel dreamcast_pci_controller = {
40 .pci_ops = &gapspci_pci_ops,
41 .resources = gapspci_resources,
42 .nr_resources = ARRAY_SIZE(gapspci_resources),
43 .io_offset = 0x00000000,
44 .mem_offset = 0x00000000,
45 };
46
47 /*
48 * gapspci init
49 */
50
gapspci_init(void)51 static int __init gapspci_init(void)
52 {
53 char idbuf[16];
54 int i;
55
56 /*
57 * FIXME: All of this wants documenting to some degree,
58 * even some basic register definitions would be nice.
59 *
60 * I haven't seen anything this ugly since.. maple.
61 */
62
63 for (i=0; i<16; i++)
64 idbuf[i] = inb(GAPSPCI_REGS+i);
65
66 if (strncmp(idbuf, "GAPSPCI_BRIDGE_2", 16))
67 return -ENODEV;
68
69 outl(0x5a14a501, GAPSPCI_REGS+0x18);
70
71 for (i=0; i<1000000; i++)
72 cpu_relax();
73
74 if (inl(GAPSPCI_REGS+0x18) != 1)
75 return -EINVAL;
76
77 outl(0x01000000, GAPSPCI_REGS+0x20);
78 outl(0x01000000, GAPSPCI_REGS+0x24);
79
80 outl(GAPSPCI_DMA_BASE, GAPSPCI_REGS+0x28);
81 outl(GAPSPCI_DMA_BASE+GAPSPCI_DMA_SIZE, GAPSPCI_REGS+0x2c);
82
83 outl(1, GAPSPCI_REGS+0x14);
84 outl(1, GAPSPCI_REGS+0x34);
85
86 /* Setting Broadband Adapter */
87 outw(0xf900, GAPSPCI_BBA_CONFIG+0x06);
88 outl(0x00000000, GAPSPCI_BBA_CONFIG+0x30);
89 outb(0x00, GAPSPCI_BBA_CONFIG+0x3c);
90 outb(0xf0, GAPSPCI_BBA_CONFIG+0x0d);
91 outw(0x0006, GAPSPCI_BBA_CONFIG+0x04);
92 outl(0x00002001, GAPSPCI_BBA_CONFIG+0x10);
93 outl(0x01000000, GAPSPCI_BBA_CONFIG+0x14);
94
95 return register_pci_controller(&dreamcast_pci_controller);
96 }
97 arch_initcall(gapspci_init);
98