1 /*
2  * arch/sh/drivers/pci/fixups-dreamcast.c
3  *
4  * PCI fixups for the Sega Dreamcast
5  *
6  * Copyright (C) 2001, 2002  M. R. Brown
7  * Copyright (C) 2002, 2003, 2006  Paul Mundt
8  *
9  * This file originally bore the message (with enclosed-$):
10  *	Id: pci.c,v 1.3 2003/05/04 19:29:46 lethal Exp
11  *	Dreamcast PCI: Supports SEGA Broadband Adaptor only.
12  *
13  * This file is subject to the terms and conditions of the GNU General Public
14  * License.  See the file "COPYING" in the main directory of this archive
15  * for more details.
16  */
17 
18 #include <linux/sched.h>
19 #include <linux/kernel.h>
20 #include <linux/param.h>
21 #include <linux/interrupt.h>
22 #include <linux/init.h>
23 #include <linux/irq.h>
24 #include <linux/pci.h>
25 #include <linux/dma-mapping.h>
26 
27 #include <asm/io.h>
28 #include <asm/irq.h>
29 #include <mach/pci.h>
30 
31 static void gapspci_fixup_resources(struct pci_dev *dev)
32 {
33 	struct pci_channel *p = dev->sysdata;
34 	struct resource res;
35 	struct pci_bus_region region;
36 
37 	printk(KERN_NOTICE "PCI: Fixing up device %s\n", pci_name(dev));
38 
39 	switch (dev->device) {
40 	case PCI_DEVICE_ID_SEGA_BBA:
41 		/*
42 		 * We also assume that dev->devfn == 0
43 		 */
44 		dev->resource[1].start	= p->resources[0].start  + 0x100;
45 		dev->resource[1].end	= dev->resource[1].start + 0x200 - 1;
46 
47 		/*
48 		 * This is not a normal BAR, prevent any attempts to move
49 		 * the BAR, as this will result in a bus lock.
50 		 */
51 		dev->resource[1].flags |= IORESOURCE_PCI_FIXED;
52 
53 		/*
54 		 * Redirect dma memory allocations to special memory window.
55 		 *
56 		 * If this GAPSPCI region were mapped by a BAR, the CPU
57 		 * phys_addr_t would be pci_resource_start(), and the bus
58 		 * address would be pci_bus_address(pci_resource_start()).
59 		 * But apparently there's no BAR mapping it, so we just
60 		 * "know" its CPU address is GAPSPCI_DMA_BASE.
61 		 */
62 		res.start = GAPSPCI_DMA_BASE;
63 		res.end = GAPSPCI_DMA_BASE + GAPSPCI_DMA_SIZE - 1;
64 		res.flags = IORESOURCE_MEM;
65 		pcibios_resource_to_bus(dev->bus, &region, &res);
66 		BUG_ON(!dma_declare_coherent_memory(&dev->dev,
67 						res.start,
68 						region.start,
69 						resource_size(&res),
70 						DMA_MEMORY_MAP |
71 						DMA_MEMORY_EXCLUSIVE));
72 		break;
73 	default:
74 		printk("PCI: Failed resource fixup\n");
75 	}
76 }
77 DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, gapspci_fixup_resources);
78 
79 int __init pcibios_map_platform_irq(const struct pci_dev *dev, u8 slot, u8 pin)
80 {
81 	/*
82 	 * The interrupt routing semantics here are quite trivial.
83 	 *
84 	 * We basically only support one interrupt, so we only bother
85 	 * updating a device's interrupt line with this single shared
86 	 * interrupt. Keeps routing quite simple, doesn't it?
87 	 */
88 	return GAPSPCI_IRQ;
89 }
90