1 /* 2 * Copyright (C) 2001,2002,2005 Broadcom Corporation 3 * Copyright (C) 2004 by Ralf Baechle (ralf@linux-mips.org) 4 * 5 * This program is free software; you can redistribute it and/or 6 * modify it under the terms of the GNU General Public License 7 * as published by the Free Software Foundation; either version 2 8 * of the License, or (at your option) any later version. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 18 */ 19 20 /* 21 * BCM1x80/1x55-specific PCI support 22 * 23 * This module provides the glue between Linux's PCI subsystem 24 * and the hardware. We basically provide glue for accessing 25 * configuration space, and set up the translation for I/O 26 * space accesses. 27 * 28 * To access configuration space, we use ioremap. In the 32-bit 29 * kernel, this consumes either 4 or 8 page table pages, and 16MB of 30 * kernel mapped memory. Hopefully neither of these should be a huge 31 * problem. 32 * 33 * XXX: AT THIS TIME, ONLY the NATIVE PCI-X INTERFACE IS SUPPORTED. 34 */ 35 #include <linux/types.h> 36 #include <linux/pci.h> 37 #include <linux/kernel.h> 38 #include <linux/init.h> 39 #include <linux/mm.h> 40 #include <linux/console.h> 41 #include <linux/tty.h> 42 #include <linux/vt.h> 43 44 #include <asm/sibyte/bcm1480_regs.h> 45 #include <asm/sibyte/bcm1480_scd.h> 46 #include <asm/sibyte/board.h> 47 #include <asm/io.h> 48 49 /* 50 * Macros for calculating offsets into config space given a device 51 * structure or dev/fun/reg 52 */ 53 #define CFGOFFSET(bus, devfn, where) (((bus)<<16)+((devfn)<<8)+(where)) 54 #define CFGADDR(bus, devfn, where) CFGOFFSET((bus)->number, (devfn), where) 55 56 static void *cfg_space; 57 58 #define PCI_BUS_ENABLED 1 59 #define PCI_DEVICE_MODE 2 60 61 static int bcm1480_bus_status; 62 63 #define PCI_BRIDGE_DEVICE 0 64 65 /* 66 * Read/write 32-bit values in config space. 67 */ 68 static inline u32 READCFG32(u32 addr) 69 { 70 return *(u32 *)(cfg_space + (addr&~3)); 71 } 72 73 static inline void WRITECFG32(u32 addr, u32 data) 74 { 75 *(u32 *)(cfg_space + (addr & ~3)) = data; 76 } 77 78 int pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin) 79 { 80 if (pin == 0) 81 return -1; 82 83 return K_BCM1480_INT_PCI_INTA - 1 + pin; 84 } 85 86 /* Do platform specific device initialization at pci_enable_device() time */ 87 int pcibios_plat_dev_init(struct pci_dev *dev) 88 { 89 return 0; 90 } 91 92 /* 93 * Some checks before doing config cycles: 94 * In PCI Device Mode, hide everything on bus 0 except the LDT host 95 * bridge. Otherwise, access is controlled by bridge MasterEn bits. 96 */ 97 static int bcm1480_pci_can_access(struct pci_bus *bus, int devfn) 98 { 99 u32 devno; 100 101 if (!(bcm1480_bus_status & (PCI_BUS_ENABLED | PCI_DEVICE_MODE))) 102 return 0; 103 104 if (bus->number == 0) { 105 devno = PCI_SLOT(devfn); 106 if (bcm1480_bus_status & PCI_DEVICE_MODE) 107 return 0; 108 else 109 return 1; 110 } else 111 return 1; 112 } 113 114 /* 115 * Read/write access functions for various sizes of values 116 * in config space. Return all 1's for disallowed accesses 117 * for a kludgy but adequate simulation of master aborts. 118 */ 119 120 static int bcm1480_pcibios_read(struct pci_bus *bus, unsigned int devfn, 121 int where, int size, u32 * val) 122 { 123 u32 data = 0; 124 125 if ((size == 2) && (where & 1)) 126 return PCIBIOS_BAD_REGISTER_NUMBER; 127 else if ((size == 4) && (where & 3)) 128 return PCIBIOS_BAD_REGISTER_NUMBER; 129 130 if (bcm1480_pci_can_access(bus, devfn)) 131 data = READCFG32(CFGADDR(bus, devfn, where)); 132 else 133 data = 0xFFFFFFFF; 134 135 if (size == 1) 136 *val = (data >> ((where & 3) << 3)) & 0xff; 137 else if (size == 2) 138 *val = (data >> ((where & 3) << 3)) & 0xffff; 139 else 140 *val = data; 141 142 return PCIBIOS_SUCCESSFUL; 143 } 144 145 static int bcm1480_pcibios_write(struct pci_bus *bus, unsigned int devfn, 146 int where, int size, u32 val) 147 { 148 u32 cfgaddr = CFGADDR(bus, devfn, where); 149 u32 data = 0; 150 151 if ((size == 2) && (where & 1)) 152 return PCIBIOS_BAD_REGISTER_NUMBER; 153 else if ((size == 4) && (where & 3)) 154 return PCIBIOS_BAD_REGISTER_NUMBER; 155 156 if (!bcm1480_pci_can_access(bus, devfn)) 157 return PCIBIOS_BAD_REGISTER_NUMBER; 158 159 data = READCFG32(cfgaddr); 160 161 if (size == 1) 162 data = (data & ~(0xff << ((where & 3) << 3))) | 163 (val << ((where & 3) << 3)); 164 else if (size == 2) 165 data = (data & ~(0xffff << ((where & 3) << 3))) | 166 (val << ((where & 3) << 3)); 167 else 168 data = val; 169 170 WRITECFG32(cfgaddr, data); 171 172 return PCIBIOS_SUCCESSFUL; 173 } 174 175 struct pci_ops bcm1480_pci_ops = { 176 bcm1480_pcibios_read, 177 bcm1480_pcibios_write, 178 }; 179 180 static struct resource bcm1480_mem_resource = { 181 .name = "BCM1480 PCI MEM", 182 .start = A_BCM1480_PHYS_PCI_MEM_MATCH_BYTES, 183 .end = A_BCM1480_PHYS_PCI_MEM_MATCH_BYTES + 0xfffffffUL, 184 .flags = IORESOURCE_MEM, 185 }; 186 187 static struct resource bcm1480_io_resource = { 188 .name = "BCM1480 PCI I/O", 189 .start = A_BCM1480_PHYS_PCI_IO_MATCH_BYTES, 190 .end = A_BCM1480_PHYS_PCI_IO_MATCH_BYTES + 0x1ffffffUL, 191 .flags = IORESOURCE_IO, 192 }; 193 194 struct pci_controller bcm1480_controller = { 195 .pci_ops = &bcm1480_pci_ops, 196 .mem_resource = &bcm1480_mem_resource, 197 .io_resource = &bcm1480_io_resource, 198 .io_offset = A_BCM1480_PHYS_PCI_IO_MATCH_BYTES, 199 }; 200 201 202 static int __init bcm1480_pcibios_init(void) 203 { 204 uint32_t cmdreg; 205 uint64_t reg; 206 207 /* CFE will assign PCI resources */ 208 pci_set_flags(PCI_PROBE_ONLY); 209 210 /* Avoid ISA compat ranges. */ 211 PCIBIOS_MIN_IO = 0x00008000UL; 212 PCIBIOS_MIN_MEM = 0x01000000UL; 213 214 /* Set I/O resource limits. - unlimited for now to accommodate HT */ 215 ioport_resource.end = 0xffffffffUL; 216 iomem_resource.end = 0xffffffffUL; 217 218 cfg_space = ioremap(A_BCM1480_PHYS_PCI_CFG_MATCH_BITS, 16*1024*1024); 219 220 /* 221 * See if the PCI bus has been configured by the firmware. 222 */ 223 reg = __raw_readq(IOADDR(A_SCD_SYSTEM_CFG)); 224 if (!(reg & M_BCM1480_SYS_PCI_HOST)) { 225 bcm1480_bus_status |= PCI_DEVICE_MODE; 226 } else { 227 cmdreg = READCFG32(CFGOFFSET(0, PCI_DEVFN(PCI_BRIDGE_DEVICE, 0), 228 PCI_COMMAND)); 229 if (!(cmdreg & PCI_COMMAND_MASTER)) { 230 printk 231 ("PCI: Skipping PCI probe. Bus is not initialized.\n"); 232 iounmap(cfg_space); 233 return 1; /* XXX */ 234 } 235 bcm1480_bus_status |= PCI_BUS_ENABLED; 236 } 237 238 /* turn on ExpMemEn */ 239 cmdreg = READCFG32(CFGOFFSET(0, PCI_DEVFN(PCI_BRIDGE_DEVICE, 0), 0x40)); 240 WRITECFG32(CFGOFFSET(0, PCI_DEVFN(PCI_BRIDGE_DEVICE, 0), 0x40), 241 cmdreg | 0x10); 242 cmdreg = READCFG32(CFGOFFSET(0, PCI_DEVFN(PCI_BRIDGE_DEVICE, 0), 0x40)); 243 244 /* 245 * Establish mappings in KSEG2 (kernel virtual) to PCI I/O 246 * space. Use "match bytes" policy to make everything look 247 * little-endian. So, you need to also set 248 * CONFIG_SWAP_IO_SPACE, but this is the combination that 249 * works correctly with most of Linux's drivers. 250 * XXX ehs: Should this happen in PCI Device mode? 251 */ 252 253 bcm1480_controller.io_map_base = (unsigned long) 254 ioremap(A_BCM1480_PHYS_PCI_IO_MATCH_BYTES, 65536); 255 bcm1480_controller.io_map_base -= bcm1480_controller.io_offset; 256 set_io_port_base(bcm1480_controller.io_map_base); 257 258 register_pci_controller(&bcm1480_controller); 259 260 #ifdef CONFIG_VGA_CONSOLE 261 console_lock(); 262 do_take_over_console(&vga_con, 0, MAX_NR_CONSOLES-1, 1); 263 console_unlock(); 264 #endif 265 return 0; 266 } 267 268 arch_initcall(bcm1480_pcibios_init); 269