1 /* 2 * arch/sh/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/config.h> 19 #include <linux/sched.h> 20 #include <linux/kernel.h> 21 #include <linux/param.h> 22 #include <linux/interrupt.h> 23 #include <linux/init.h> 24 #include <linux/irq.h> 25 #include <linux/pci.h> 26 27 #include <asm/io.h> 28 #include <asm/irq.h> 29 #include <asm/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 static struct pci_ops gapspci_pci_ops; 46 47 struct pci_channel board_pci_channels[] = { 48 { &gapspci_pci_ops, &gapspci_io_resource, 49 &gapspci_mem_resource, 0, 1 }, 50 { 0, } 51 }; 52 53 /* 54 * The !gapspci_config_access case really shouldn't happen, ever, unless 55 * someone implicitly messes around with the last devfn value.. otherwise we 56 * only support a single device anyways, and if we didn't have a BBA, we 57 * wouldn't make it terribly far through the PCI setup anyways. 58 * 59 * Also, we could very easily support both Type 0 and Type 1 configurations 60 * here, but since it doesn't seem that there is any such implementation in 61 * existance, we don't bother. 62 * 63 * I suppose if someone actually gets around to ripping the chip out of 64 * the BBA and hanging some more devices off of it, then this might be 65 * something to take into consideration. However, due to the cost of the BBA, 66 * and the general lack of activity by DC hardware hackers, this doesn't seem 67 * likely to happen anytime soon. 68 */ 69 static int gapspci_config_access(unsigned char bus, unsigned int devfn) 70 { 71 return (bus == 0) && (devfn == 0); 72 } 73 74 /* 75 * We can also actually read and write in b/w/l sizes! Thankfully this part 76 * was at least done right, and we don't have to do the stupid masking and 77 * shifting that we do on the 7751! Small wonders never cease to amaze. 78 */ 79 static int gapspci_read(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *val) 80 { 81 *val = 0xffffffff; 82 83 if (!gapspci_config_access(bus->number, devfn)) 84 return PCIBIOS_DEVICE_NOT_FOUND; 85 86 switch (size) { 87 case 1: *val = inb(GAPSPCI_BBA_CONFIG+where); break; 88 case 2: *val = inw(GAPSPCI_BBA_CONFIG+where); break; 89 case 4: *val = inl(GAPSPCI_BBA_CONFIG+where); break; 90 } 91 92 return PCIBIOS_SUCCESSFUL; 93 } 94 95 static int gapspci_write(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 val) 96 { 97 if (!gapspci_config_access(bus->number, devfn)) 98 return PCIBIOS_DEVICE_NOT_FOUND; 99 100 switch (size) { 101 case 1: outb(( u8)val, GAPSPCI_BBA_CONFIG+where); break; 102 case 2: outw((u16)val, GAPSPCI_BBA_CONFIG+where); break; 103 case 4: outl((u32)val, GAPSPCI_BBA_CONFIG+where); break; 104 } 105 106 return PCIBIOS_SUCCESSFUL; 107 } 108 109 static struct pci_ops gapspci_pci_ops = { 110 .read = gapspci_read, 111 .write = gapspci_write, 112 }; 113 114 /* 115 * gapspci init 116 */ 117 118 int __init gapspci_init(void) 119 { 120 char idbuf[16]; 121 int i; 122 123 /* 124 * FIXME: All of this wants documenting to some degree, 125 * even some basic register definitions would be nice. 126 * 127 * I haven't seen anything this ugly since.. maple. 128 */ 129 130 for (i=0; i<16; i++) 131 idbuf[i] = inb(GAPSPCI_REGS+i); 132 133 if (strncmp(idbuf, "GAPSPCI_BRIDGE_2", 16)) 134 return -ENODEV; 135 136 outl(0x5a14a501, GAPSPCI_REGS+0x18); 137 138 for (i=0; i<1000000; i++) 139 ; 140 141 if (inl(GAPSPCI_REGS+0x18) != 1) 142 return -EINVAL; 143 144 outl(0x01000000, GAPSPCI_REGS+0x20); 145 outl(0x01000000, GAPSPCI_REGS+0x24); 146 147 outl(GAPSPCI_DMA_BASE, GAPSPCI_REGS+0x28); 148 outl(GAPSPCI_DMA_BASE+GAPSPCI_DMA_SIZE, GAPSPCI_REGS+0x2c); 149 150 outl(1, GAPSPCI_REGS+0x14); 151 outl(1, GAPSPCI_REGS+0x34); 152 153 /* Setting Broadband Adapter */ 154 outw(0xf900, GAPSPCI_BBA_CONFIG+0x06); 155 outl(0x00000000, GAPSPCI_BBA_CONFIG+0x30); 156 outb(0x00, GAPSPCI_BBA_CONFIG+0x3c); 157 outb(0xf0, GAPSPCI_BBA_CONFIG+0x0d); 158 outw(0x0006, GAPSPCI_BBA_CONFIG+0x04); 159 outl(0x00002001, GAPSPCI_BBA_CONFIG+0x10); 160 outl(0x01000000, GAPSPCI_BBA_CONFIG+0x14); 161 162 return 0; 163 } 164 165 /* Haven't done anything here as yet */ 166 char * __devinit pcibios_setup(char *str) 167 { 168 return str; 169 } 170