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 43 #include <asm/sibyte/bcm1480_regs.h> 44 #include <asm/sibyte/bcm1480_scd.h> 45 #include <asm/sibyte/board.h> 46 #include <asm/io.h> 47 48 /* 49 * Macros for calculating offsets into config space given a device 50 * structure or dev/fun/reg 51 */ 52 #define CFGOFFSET(bus, devfn, where) (((bus)<<16)+((devfn)<<8)+(where)) 53 #define CFGADDR(bus, devfn, where) CFGOFFSET((bus)->number, (devfn), where) 54 55 static void *cfg_space; 56 57 #define PCI_BUS_ENABLED 1 58 #define PCI_DEVICE_MODE 2 59 60 static int bcm1480_bus_status; 61 62 #define PCI_BRIDGE_DEVICE 0 63 64 /* 65 * Read/write 32-bit values in config space. 66 */ 67 static inline u32 READCFG32(u32 addr) 68 { 69 return *(u32 *)(cfg_space + (addr&~3)); 70 } 71 72 static inline void WRITECFG32(u32 addr, u32 data) 73 { 74 *(u32 *)(cfg_space + (addr & ~3)) = data; 75 } 76 77 int pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin) 78 { 79 if (pin == 0) 80 return -1; 81 82 return K_BCM1480_INT_PCI_INTA - 1 + pin; 83 } 84 85 /* Do platform specific device initialization at pci_enable_device() time */ 86 int pcibios_plat_dev_init(struct pci_dev *dev) 87 { 88 return 0; 89 } 90 91 /* 92 * Some checks before doing config cycles: 93 * In PCI Device Mode, hide everything on bus 0 except the LDT host 94 * bridge. Otherwise, access is controlled by bridge MasterEn bits. 95 */ 96 static int bcm1480_pci_can_access(struct pci_bus *bus, int devfn) 97 { 98 u32 devno; 99 100 if (!(bcm1480_bus_status & (PCI_BUS_ENABLED | PCI_DEVICE_MODE))) 101 return 0; 102 103 if (bus->number == 0) { 104 devno = PCI_SLOT(devfn); 105 if (bcm1480_bus_status & PCI_DEVICE_MODE) 106 return 0; 107 else 108 return 1; 109 } else 110 return 1; 111 } 112 113 /* 114 * Read/write access functions for various sizes of values 115 * in config space. Return all 1's for disallowed accesses 116 * for a kludgy but adequate simulation of master aborts. 117 */ 118 119 static int bcm1480_pcibios_read(struct pci_bus *bus, unsigned int devfn, 120 int where, int size, u32 * val) 121 { 122 u32 data = 0; 123 124 if ((size == 2) && (where & 1)) 125 return PCIBIOS_BAD_REGISTER_NUMBER; 126 else if ((size == 4) && (where & 3)) 127 return PCIBIOS_BAD_REGISTER_NUMBER; 128 129 if (bcm1480_pci_can_access(bus, devfn)) 130 data = READCFG32(CFGADDR(bus, devfn, where)); 131 else 132 data = 0xFFFFFFFF; 133 134 if (size == 1) 135 *val = (data >> ((where & 3) << 3)) & 0xff; 136 else if (size == 2) 137 *val = (data >> ((where & 3) << 3)) & 0xffff; 138 else 139 *val = data; 140 141 return PCIBIOS_SUCCESSFUL; 142 } 143 144 static int bcm1480_pcibios_write(struct pci_bus *bus, unsigned int devfn, 145 int where, int size, u32 val) 146 { 147 u32 cfgaddr = CFGADDR(bus, devfn, where); 148 u32 data = 0; 149 150 if ((size == 2) && (where & 1)) 151 return PCIBIOS_BAD_REGISTER_NUMBER; 152 else if ((size == 4) && (where & 3)) 153 return PCIBIOS_BAD_REGISTER_NUMBER; 154 155 if (!bcm1480_pci_can_access(bus, devfn)) 156 return PCIBIOS_BAD_REGISTER_NUMBER; 157 158 data = READCFG32(cfgaddr); 159 160 if (size == 1) 161 data = (data & ~(0xff << ((where & 3) << 3))) | 162 (val << ((where & 3) << 3)); 163 else if (size == 2) 164 data = (data & ~(0xffff << ((where & 3) << 3))) | 165 (val << ((where & 3) << 3)); 166 else 167 data = val; 168 169 WRITECFG32(cfgaddr, data); 170 171 return PCIBIOS_SUCCESSFUL; 172 } 173 174 struct pci_ops bcm1480_pci_ops = { 175 bcm1480_pcibios_read, 176 bcm1480_pcibios_write, 177 }; 178 179 static struct resource bcm1480_mem_resource = { 180 .name = "BCM1480 PCI MEM", 181 .start = A_BCM1480_PHYS_PCI_MEM_MATCH_BYTES, 182 .end = A_BCM1480_PHYS_PCI_MEM_MATCH_BYTES + 0xfffffffUL, 183 .flags = IORESOURCE_MEM, 184 }; 185 186 static struct resource bcm1480_io_resource = { 187 .name = "BCM1480 PCI I/O", 188 .start = A_BCM1480_PHYS_PCI_IO_MATCH_BYTES, 189 .end = A_BCM1480_PHYS_PCI_IO_MATCH_BYTES + 0x1ffffffUL, 190 .flags = IORESOURCE_IO, 191 }; 192 193 struct pci_controller bcm1480_controller = { 194 .pci_ops = &bcm1480_pci_ops, 195 .mem_resource = &bcm1480_mem_resource, 196 .io_resource = &bcm1480_io_resource, 197 .io_offset = A_BCM1480_PHYS_PCI_IO_MATCH_BYTES, 198 }; 199 200 201 static int __init bcm1480_pcibios_init(void) 202 { 203 uint32_t cmdreg; 204 uint64_t reg; 205 206 /* CFE will assign PCI resources */ 207 pci_set_flags(PCI_PROBE_ONLY); 208 209 /* Avoid ISA compat ranges. */ 210 PCIBIOS_MIN_IO = 0x00008000UL; 211 PCIBIOS_MIN_MEM = 0x01000000UL; 212 213 /* Set I/O resource limits. - unlimited for now to accommodate HT */ 214 ioport_resource.end = 0xffffffffUL; 215 iomem_resource.end = 0xffffffffUL; 216 217 cfg_space = ioremap(A_BCM1480_PHYS_PCI_CFG_MATCH_BITS, 16*1024*1024); 218 219 /* 220 * See if the PCI bus has been configured by the firmware. 221 */ 222 reg = __raw_readq(IOADDR(A_SCD_SYSTEM_CFG)); 223 if (!(reg & M_BCM1480_SYS_PCI_HOST)) { 224 bcm1480_bus_status |= PCI_DEVICE_MODE; 225 } else { 226 cmdreg = READCFG32(CFGOFFSET(0, PCI_DEVFN(PCI_BRIDGE_DEVICE, 0), 227 PCI_COMMAND)); 228 if (!(cmdreg & PCI_COMMAND_MASTER)) { 229 printk 230 ("PCI: Skipping PCI probe. Bus is not initialized.\n"); 231 iounmap(cfg_space); 232 return 1; /* XXX */ 233 } 234 bcm1480_bus_status |= PCI_BUS_ENABLED; 235 } 236 237 /* turn on ExpMemEn */ 238 cmdreg = READCFG32(CFGOFFSET(0, PCI_DEVFN(PCI_BRIDGE_DEVICE, 0), 0x40)); 239 WRITECFG32(CFGOFFSET(0, PCI_DEVFN(PCI_BRIDGE_DEVICE, 0), 0x40), 240 cmdreg | 0x10); 241 cmdreg = READCFG32(CFGOFFSET(0, PCI_DEVFN(PCI_BRIDGE_DEVICE, 0), 0x40)); 242 243 /* 244 * Establish mappings in KSEG2 (kernel virtual) to PCI I/O 245 * space. Use "match bytes" policy to make everything look 246 * little-endian. So, you need to also set 247 * CONFIG_SWAP_IO_SPACE, but this is the combination that 248 * works correctly with most of Linux's drivers. 249 * XXX ehs: Should this happen in PCI Device mode? 250 */ 251 252 bcm1480_controller.io_map_base = (unsigned long) 253 ioremap(A_BCM1480_PHYS_PCI_IO_MATCH_BYTES, 65536); 254 bcm1480_controller.io_map_base -= bcm1480_controller.io_offset; 255 set_io_port_base(bcm1480_controller.io_map_base); 256 257 register_pci_controller(&bcm1480_controller); 258 259 #ifdef CONFIG_VGA_CONSOLE 260 take_over_console(&vga_con, 0, MAX_NR_CONSOLES-1, 1); 261 #endif 262 return 0; 263 } 264 265 arch_initcall(bcm1480_pcibios_init); 266