1 /* 2 * arch/sh/drivers/pci/ops-dreamcast.c 3 * 4 * PCI operations for the Sega Dreamcast 5 * 6 * Copyright (C) 2001, 2002 M. R. Brown 7 * Copyright (C) 2002, 2003 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/module.h> 26 27 #include <asm/io.h> 28 #include <asm/irq.h> 29 #include <mach/pci.h> 30 31 static struct resource gapspci_io_resource = { 32 .name = "GAPSPCI IO", 33 .start = GAPSPCI_BBA_CONFIG, 34 .end = GAPSPCI_BBA_CONFIG + GAPSPCI_BBA_CONFIG_SIZE - 1, 35 .flags = IORESOURCE_IO, 36 }; 37 38 static struct resource gapspci_mem_resource = { 39 .name = "GAPSPCI mem", 40 .start = GAPSPCI_DMA_BASE, 41 .end = GAPSPCI_DMA_BASE + GAPSPCI_DMA_SIZE - 1, 42 .flags = IORESOURCE_MEM, 43 }; 44 45 /* 46 * The !gapspci_config_access case really shouldn't happen, ever, unless 47 * someone implicitly messes around with the last devfn value.. otherwise we 48 * only support a single device anyways, and if we didn't have a BBA, we 49 * wouldn't make it terribly far through the PCI setup anyways. 50 * 51 * Also, we could very easily support both Type 0 and Type 1 configurations 52 * here, but since it doesn't seem that there is any such implementation in 53 * existence, we don't bother. 54 * 55 * I suppose if someone actually gets around to ripping the chip out of 56 * the BBA and hanging some more devices off of it, then this might be 57 * something to take into consideration. However, due to the cost of the BBA, 58 * and the general lack of activity by DC hardware hackers, this doesn't seem 59 * likely to happen anytime soon. 60 */ 61 static int gapspci_config_access(unsigned char bus, unsigned int devfn) 62 { 63 return (bus == 0) && (devfn == 0); 64 } 65 66 /* 67 * We can also actually read and write in b/w/l sizes! Thankfully this part 68 * was at least done right, and we don't have to do the stupid masking and 69 * shifting that we do on the 7751! Small wonders never cease to amaze. 70 */ 71 static int gapspci_read(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *val) 72 { 73 *val = 0xffffffff; 74 75 if (!gapspci_config_access(bus->number, devfn)) 76 return PCIBIOS_DEVICE_NOT_FOUND; 77 78 switch (size) { 79 case 1: *val = inb(GAPSPCI_BBA_CONFIG+where); break; 80 case 2: *val = inw(GAPSPCI_BBA_CONFIG+where); break; 81 case 4: *val = inl(GAPSPCI_BBA_CONFIG+where); break; 82 } 83 84 return PCIBIOS_SUCCESSFUL; 85 } 86 87 static int gapspci_write(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 val) 88 { 89 if (!gapspci_config_access(bus->number, devfn)) 90 return PCIBIOS_DEVICE_NOT_FOUND; 91 92 switch (size) { 93 case 1: outb(( u8)val, GAPSPCI_BBA_CONFIG+where); break; 94 case 2: outw((u16)val, GAPSPCI_BBA_CONFIG+where); break; 95 case 4: outl((u32)val, GAPSPCI_BBA_CONFIG+where); break; 96 } 97 98 return PCIBIOS_SUCCESSFUL; 99 } 100 101 static struct pci_ops gapspci_pci_ops = { 102 .read = gapspci_read, 103 .write = gapspci_write, 104 }; 105 106 /* 107 * gapspci init 108 */ 109 110 static int __init gapspci_init(struct pci_channel *chan) 111 { 112 char idbuf[16]; 113 int i; 114 115 /* 116 * FIXME: All of this wants documenting to some degree, 117 * even some basic register definitions would be nice. 118 * 119 * I haven't seen anything this ugly since.. maple. 120 */ 121 122 for (i=0; i<16; i++) 123 idbuf[i] = inb(GAPSPCI_REGS+i); 124 125 if (strncmp(idbuf, "GAPSPCI_BRIDGE_2", 16)) 126 return -ENODEV; 127 128 outl(0x5a14a501, GAPSPCI_REGS+0x18); 129 130 for (i=0; i<1000000; i++) 131 ; 132 133 if (inl(GAPSPCI_REGS+0x18) != 1) 134 return -EINVAL; 135 136 outl(0x01000000, GAPSPCI_REGS+0x20); 137 outl(0x01000000, GAPSPCI_REGS+0x24); 138 139 outl(GAPSPCI_DMA_BASE, GAPSPCI_REGS+0x28); 140 outl(GAPSPCI_DMA_BASE+GAPSPCI_DMA_SIZE, GAPSPCI_REGS+0x2c); 141 142 outl(1, GAPSPCI_REGS+0x14); 143 outl(1, GAPSPCI_REGS+0x34); 144 145 /* Setting Broadband Adapter */ 146 outw(0xf900, GAPSPCI_BBA_CONFIG+0x06); 147 outl(0x00000000, GAPSPCI_BBA_CONFIG+0x30); 148 outb(0x00, GAPSPCI_BBA_CONFIG+0x3c); 149 outb(0xf0, GAPSPCI_BBA_CONFIG+0x0d); 150 outw(0x0006, GAPSPCI_BBA_CONFIG+0x04); 151 outl(0x00002001, GAPSPCI_BBA_CONFIG+0x10); 152 outl(0x01000000, GAPSPCI_BBA_CONFIG+0x14); 153 154 return 0; 155 } 156 157 /* Haven't done anything here as yet */ 158 char * __devinit pcibios_setup(char *str) 159 { 160 return str; 161 } 162 163 struct pci_channel board_pci_channels[] = { 164 { gapspci_init, &gapspci_pci_ops, &gapspci_io_resource, 165 &gapspci_mem_resource, 0, 1 }, 166 { 0, } 167 }; 168