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-mapping.h> 23 24 #include <asm/io.h> 25 #include <asm/irq.h> 26 #include <mach/pci.h> 27 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 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