1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * arch/sh/drivers/pci/fixups-dreamcast.c
4 *
5 * PCI fixups for the Sega Dreamcast
6 *
7 * Copyright (C) 2001, 2002 M. R. Brown
8 * Copyright (C) 2002, 2003, 2006 Paul Mundt
9 *
10 * This file originally bore the message (with enclosed-$):
11 * Id: pci.c,v 1.3 2003/05/04 19:29:46 lethal Exp
12 * Dreamcast PCI: Supports SEGA Broadband Adaptor only.
13 */
14
15 #include <linux/sched.h>
16 #include <linux/kernel.h>
17 #include <linux/param.h>
18 #include <linux/interrupt.h>
19 #include <linux/init.h>
20 #include <linux/irq.h>
21 #include <linux/pci.h>
22 #include <linux/dma-map-ops.h>
23
24 #include <asm/io.h>
25 #include <asm/irq.h>
26 #include <mach/pci.h>
27
gapspci_fixup_resources(struct pci_dev * dev)28 static void gapspci_fixup_resources(struct pci_dev *dev)
29 {
30 struct pci_channel *p = dev->sysdata;
31 struct resource res;
32 struct pci_bus_region region;
33
34 printk(KERN_NOTICE "PCI: Fixing up device %s\n", pci_name(dev));
35
36 switch (dev->device) {
37 case PCI_DEVICE_ID_SEGA_BBA:
38 /*
39 * We also assume that dev->devfn == 0
40 */
41 dev->resource[1].start = p->resources[0].start + 0x100;
42 dev->resource[1].end = dev->resource[1].start + 0x200 - 1;
43
44 /*
45 * This is not a normal BAR, prevent any attempts to move
46 * the BAR, as this will result in a bus lock.
47 */
48 dev->resource[1].flags |= IORESOURCE_PCI_FIXED;
49
50 /*
51 * Redirect dma memory allocations to special memory window.
52 *
53 * If this GAPSPCI region were mapped by a BAR, the CPU
54 * phys_addr_t would be pci_resource_start(), and the bus
55 * address would be pci_bus_address(pci_resource_start()).
56 * But apparently there's no BAR mapping it, so we just
57 * "know" its CPU address is GAPSPCI_DMA_BASE.
58 */
59 res.start = GAPSPCI_DMA_BASE;
60 res.end = GAPSPCI_DMA_BASE + GAPSPCI_DMA_SIZE - 1;
61 res.flags = IORESOURCE_MEM;
62 pcibios_resource_to_bus(dev->bus, ®ion, &res);
63 BUG_ON(dma_declare_coherent_memory(&dev->dev,
64 res.start,
65 region.start,
66 resource_size(&res)));
67 break;
68 default:
69 printk("PCI: Failed resource fixup\n");
70 }
71 }
72 DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, gapspci_fixup_resources);
73
pcibios_map_platform_irq(const struct pci_dev * dev,u8 slot,u8 pin)74 int pcibios_map_platform_irq(const struct pci_dev *dev, u8 slot, u8 pin)
75 {
76 /*
77 * The interrupt routing semantics here are quite trivial.
78 *
79 * We basically only support one interrupt, so we only bother
80 * updating a device's interrupt line with this single shared
81 * interrupt. Keeps routing quite simple, doesn't it?
82 */
83 return GAPSPCI_IRQ;
84 }
85