arch/sh/drivers/pci/pci-auto.c

   1 /*
   2  * PCI autoconfiguration library
   3  *
   4  * Author: Matt Porter <mporter@mvista.com>
   5  *
   6  * Copyright 2000, 2001 MontaVista Software Inc.
   7  * Copyright 2001 Bradley D. LaRonde <brad@ltc.com>
   8  * Copyright 2003 Paul Mundt <lethal@linux-sh.org>
   9  *
  10  * This program is free software; you can redistribute  it and/or modify it
  11  * under  the terms of  the GNU General  Public License as published by the
  12  * Free Software Foundation;  either version 2 of the  License, or (at your
  13  * option) any later version.
  14  */
  15
  16 /*
  17  * Modified for MIPS by Jun Sun, jsun@mvista.com
  18  *
  19  * . Simplify the interface between pci_auto and the rest: a single function.
  20  * . Assign resources from low address to upper address.
  21  * . change most int to u32.
  22  *
  23  * Further modified to include it as mips generic code, ppopov@mvista.com.
  24  *
  25  * 2001-10-26  Bradley D. LaRonde <brad@ltc.com>
  26  * - Add a top_bus argument to the "early config" functions so that
  27  *   they can set a fake parent bus pointer to convince the underlying
  28  *   pci ops to use type 1 configuration for sub busses.
  29  * - Set bridge base and limit registers correctly.
  30  * - Align io and memory base properly before and after bridge setup.
  31  * - Don't fall through to pci_setup_bars for bridge.
  32  * - Reformat the debug output to look more like lspci's output.
  33  *
  34  * Cloned for SuperH by M. R. Brown, mrbrown@0xd6.org
  35  *
  36  * 2003-08-05  Paul Mundt <lethal@linux-sh.org>
  37  * - Don't update the BAR values on systems that already have valid addresses
  38  *   and don't want these updated for whatever reason, by way of a new config
  39  *   option check. However, we still read in the old BAR values so that they
  40  *   can still be reported through the debug output.
  41  */
  42
  43 #include <linux/kernel.h>
  44 #include <linux/init.h>
  45 #include <linux/types.h>
  46 #include <linux/pci.h>
  47
  48 #define DEBUG
  49 #ifdef  DEBUG
  50 #define DBG(x...)       printk(x)
  51 #else
  52 #define DBG(x...)
  53 #endif
  54
  55 /*
  56  * These functions are used early on before PCI scanning is done
  57  * and all of the pci_dev and pci_bus structures have been created.
  58  */
  59 static struct pci_dev *fake_pci_dev(struct pci_channel *hose,
  60         int top_bus, int busnr, int devfn)
  61 {
  62         static struct pci_dev dev;
  63         static struct pci_bus bus;
  64
  65         dev.bus = &bus;
  66         dev.sysdata = hose;
  67         dev.devfn = devfn;
  68         bus.number = busnr;
  69         bus.ops = hose->pci_ops;
  70
  71         if(busnr != top_bus)
  72                 /* Fake a parent bus structure. */
  73                 bus.parent = &bus;
  74         else
  75                 bus.parent = NULL;
  76
  77         return &dev;
  78 }
  79
  80 #define EARLY_PCI_OP(rw, size, type)                                    \
  81 int early_##rw##_config_##size(struct pci_channel *hose,                \
  82         int top_bus, int bus, int devfn, int offset, type value)        \
  83 {                                                                       \
  84         return pci_##rw##_config_##size(                                \
  85                 fake_pci_dev(hose, top_bus, bus, devfn),                \
  86                 offset, value);                                         \
  87 }
  88
  89 EARLY_PCI_OP(read, byte, u8 *)
  90 EARLY_PCI_OP(read, word, u16 *)
  91 EARLY_PCI_OP(read, dword, u32 *)
  92 EARLY_PCI_OP(write, byte, u8)
  93 EARLY_PCI_OP(write, word, u16)
  94 EARLY_PCI_OP(write, dword, u32)
  95
  96 static struct resource *io_resource_inuse;
  97 static struct resource *mem_resource_inuse;
  98
  99 static u32 pciauto_lower_iospc;
 100 static u32 pciauto_upper_iospc;
 101
 102 static u32 pciauto_lower_memspc;
 103 static u32 pciauto_upper_memspc;
 104
 105 static void __init
 106 pciauto_setup_bars(struct pci_channel *hose,
 107                    int top_bus,
 108                    int current_bus,
 109                    int pci_devfn,
 110                    int bar_limit)
 111 {
 112         u32 bar_response, bar_size, bar_value;
 113         u32 bar, addr_mask, bar_nr = 0;
 114         u32 * upper_limit;
 115         u32 * lower_limit;
 116         int found_mem64 = 0;
 117
 118         for (bar = PCI_BASE_ADDRESS_0; bar <= bar_limit; bar+=4) {
 119                 u32 bar_addr;
 120
 121                 /* Read the old BAR value */
 122                 early_read_config_dword(hose, top_bus,
 123                                         current_bus,
 124                                         pci_devfn,
 125                                         bar,
 126                                         &bar_addr);
 127
 128                 /* Tickle the BAR and get the response */
 129                 early_write_config_dword(hose, top_bus,
 130                                          current_bus,
 131                                          pci_devfn,
 132                                          bar,
 133                                          0xffffffff);
 134
 135                 early_read_config_dword(hose, top_bus,
 136                                         current_bus,
 137                                         pci_devfn,
 138                                         bar,
 139                                         &bar_response);
 140
 141                 /*
 142                  * Write the old BAR value back out, only update the BAR
 143                  * if we implicitly want resources to be updated, which
 144                  * is done by the generic code further down. -- PFM.
 145                  */
 146                 early_write_config_dword(hose, top_bus,
 147                                          current_bus,
 148                                          pci_devfn,
 149                                          bar,
 150                                          bar_addr);
 151
 152                 /* If BAR is not implemented go to the next BAR */
 153                 if (!bar_response)
 154                         continue;
 155
 156                 /*
 157                  * Workaround for a BAR that doesn't use its upper word,
 158                  * like the ALi 1535D+ PCI DC-97 Controller Modem (M5457).
 159                  * bdl <brad@ltc.com>
 160                  */
 161                 if (!(bar_response & 0xffff0000))
 162                         bar_response |= 0xffff0000;
 163
 164 retry:
 165                 /* Check the BAR type and set our address mask */
 166                 if (bar_response & PCI_BASE_ADDRESS_SPACE) {
 167                         addr_mask = PCI_BASE_ADDRESS_IO_MASK;
 168                         upper_limit = &pciauto_upper_iospc;
 169                         lower_limit = &pciauto_lower_iospc;
 170                         DBG("        I/O");
 171                 } else {
 172                         if ((bar_response & PCI_BASE_ADDRESS_MEM_TYPE_MASK) ==
 173                             PCI_BASE_ADDRESS_MEM_TYPE_64)
 174                                 found_mem64 = 1;
 175
 176                         addr_mask = PCI_BASE_ADDRESS_MEM_MASK;
 177                         upper_limit = &pciauto_upper_memspc;
 178                         lower_limit = &pciauto_lower_memspc;
 179                         DBG("        Mem");
 180                 }
 181
 182
 183                 /* Calculate requested size */
 184                 bar_size = ~(bar_response & addr_mask) + 1;
 185
 186                 /* Allocate a base address */
 187                 bar_value = ((*lower_limit - 1) & ~(bar_size - 1)) + bar_size;
 188
 189                 if ((bar_value + bar_size) > *upper_limit) {
 190                         if (bar_response & PCI_BASE_ADDRESS_SPACE) {
 191                                 if (io_resource_inuse->child) {
 192                                         io_resource_inuse =
 193                                                 io_resource_inuse->child;
 194                                         pciauto_lower_iospc =
 195                                                 io_resource_inuse->start;
 196                                         pciauto_upper_iospc =
 197                                                 io_resource_inuse->end + 1;
 198                                         goto retry;
 199                                 }
 200
 201                         } else {
 202                                 if (mem_resource_inuse->child) {
 203                                         mem_resource_inuse =
 204                                                 mem_resource_inuse->child;
 205                                         pciauto_lower_memspc =
 206                                                 mem_resource_inuse->start;
 207                                         pciauto_upper_memspc =
 208                                                 mem_resource_inuse->end + 1;
 209                                         goto retry;
 210                                 }
 211                         }
 212                         DBG(" unavailable -- skipping, value %x size %x\n",
 213                                         bar_value, bar_size);
 214                         continue;
 215                 }
 216
 217                 if (bar_value < *lower_limit || (bar_value + bar_size) >= *upper_limit) {
 218                         DBG(" unavailable -- skipping, value %x size %x\n",
 219                                         bar_value, bar_size);
 220                         continue;
 221                 }
 222
 223 #ifdef CONFIG_PCI_AUTO_UPDATE_RESOURCES
 224                 /* Write it out and update our limit */
 225                 early_write_config_dword(hose, top_bus, current_bus, pci_devfn,
 226                                          bar, bar_value);
 227 #endif
 228
 229                 *lower_limit = bar_value + bar_size;
 230
 231                 /*
 232                  * If we are a 64-bit decoder then increment to the
 233                  * upper 32 bits of the bar and force it to locate
 234                  * in the lower 4GB of memory.
 235                  */
 236                 if (found_mem64) {
 237                         bar += 4;
 238                         early_write_config_dword(hose, top_bus,
 239                                                  current_bus,
 240                                                  pci_devfn,
 241                                                  bar,
 242                                                  0x00000000);
 243                 }
 244
 245                 DBG(" at 0x%.8x [size=0x%x]\n", bar_value, bar_size);
 246
 247                 bar_nr++;
 248         }
 249
 250 }
 251
 252 static void __init
 253 pciauto_prescan_setup_bridge(struct pci_channel *hose,
 254                              int top_bus,
 255                              int current_bus,
 256                              int pci_devfn,
 257                              int sub_bus)
 258 {
 259         /* Configure bus number registers */
 260         early_write_config_byte(hose, top_bus, current_bus, pci_devfn,
 261                                 PCI_PRIMARY_BUS, current_bus);
 262         early_write_config_byte(hose, top_bus, current_bus, pci_devfn,
 263                                 PCI_SECONDARY_BUS, sub_bus + 1);
 264         early_write_config_byte(hose, top_bus, current_bus, pci_devfn,
 265                                 PCI_SUBORDINATE_BUS, 0xff);
 266
 267         /* Align memory and I/O to 1MB and 4KB boundaries. */
 268         pciauto_lower_memspc = (pciauto_lower_memspc + (0x100000 - 1))
 269                 & ~(0x100000 - 1);
 270         pciauto_lower_iospc = (pciauto_lower_iospc + (0x1000 - 1))
 271                 & ~(0x1000 - 1);
 272
 273         /* Set base (lower limit) of address range behind bridge. */
 274         early_write_config_word(hose, top_bus, current_bus, pci_devfn,
 275                 PCI_MEMORY_BASE, pciauto_lower_memspc >> 16);
 276         early_write_config_byte(hose, top_bus, current_bus, pci_devfn,
 277                 PCI_IO_BASE, (pciauto_lower_iospc & 0x0000f000) >> 8);
 278         early_write_config_word(hose, top_bus, current_bus, pci_devfn,
 279                 PCI_IO_BASE_UPPER16, pciauto_lower_iospc >> 16);
 280
 281         /* We don't support prefetchable memory for now, so disable */
 282         early_write_config_word(hose, top_bus, current_bus, pci_devfn,
 283                                 PCI_PREF_MEMORY_BASE, 0);
 284         early_write_config_word(hose, top_bus, current_bus, pci_devfn,
 285                                 PCI_PREF_MEMORY_LIMIT, 0);
 286 }
 287
 288 static void __init
 289 pciauto_postscan_setup_bridge(struct pci_channel *hose,
 290                               int top_bus,
 291                               int current_bus,
 292                               int pci_devfn,
 293                               int sub_bus)
 294 {
 295         u32 temp;
 296
 297         /*
 298          * [jsun] we always bump up baselines a little, so that if there
 299          * nothing behind P2P bridge, we don't wind up overlapping IO/MEM
 300          * spaces.
 301          */
 302         pciauto_lower_memspc += 1;
 303         pciauto_lower_iospc += 1;
 304
 305         /* Configure bus number registers */
 306         early_write_config_byte(hose, top_bus, current_bus, pci_devfn,
 307                                 PCI_SUBORDINATE_BUS, sub_bus);
 308
 309         /* Set upper limit of address range behind bridge. */
 310         early_write_config_word(hose, top_bus, current_bus, pci_devfn,
 311                 PCI_MEMORY_LIMIT, pciauto_lower_memspc >> 16);
 312         early_write_config_byte(hose, top_bus, current_bus, pci_devfn,
 313                 PCI_IO_LIMIT, (pciauto_lower_iospc & 0x0000f000) >> 8);
 314         early_write_config_word(hose, top_bus, current_bus, pci_devfn,
 315                 PCI_IO_LIMIT_UPPER16, pciauto_lower_iospc >> 16);
 316
 317         /* Align memory and I/O to 1MB and 4KB boundaries. */
 318         pciauto_lower_memspc = (pciauto_lower_memspc + (0x100000 - 1))
 319                 & ~(0x100000 - 1);
 320         pciauto_lower_iospc = (pciauto_lower_iospc + (0x1000 - 1))
 321                 & ~(0x1000 - 1);
 322
 323         /* Enable memory and I/O accesses, enable bus master */
 324         early_read_config_dword(hose, top_bus, current_bus, pci_devfn,
 325                 PCI_COMMAND, &temp);
 326         early_write_config_dword(hose, top_bus, current_bus, pci_devfn,
 327                 PCI_COMMAND, temp | PCI_COMMAND_IO | PCI_COMMAND_MEMORY
 328                 | PCI_COMMAND_MASTER);
 329 }
 330
 331 static void __init
 332 pciauto_prescan_setup_cardbus_bridge(struct pci_channel *hose,
 333                         int top_bus,
 334                         int current_bus,
 335                         int pci_devfn,
 336                         int sub_bus)
 337 {
 338         /* Configure bus number registers */
 339         early_write_config_byte(hose, top_bus, current_bus, pci_devfn,
 340                                 PCI_PRIMARY_BUS, current_bus);
 341         early_write_config_byte(hose, top_bus, current_bus, pci_devfn,
 342                                 PCI_SECONDARY_BUS, sub_bus + 1);
 343         early_write_config_byte(hose, top_bus, current_bus, pci_devfn,
 344                                 PCI_SUBORDINATE_BUS, 0xff);
 345
 346         /* Align memory and I/O to 4KB and 4 byte boundaries. */
 347         pciauto_lower_memspc = (pciauto_lower_memspc + (0x1000 - 1))
 348                 & ~(0x1000 - 1);
 349         pciauto_lower_iospc = (pciauto_lower_iospc + (0x4 - 1))
 350                 & ~(0x4 - 1);
 351
 352         early_write_config_dword(hose, top_bus, current_bus, pci_devfn,
 353                 PCI_CB_MEMORY_BASE_0, pciauto_lower_memspc);
 354         early_write_config_dword(hose, top_bus, current_bus, pci_devfn,
 355                 PCI_CB_IO_BASE_0, pciauto_lower_iospc);
 356 }
 357
 358 static void __init
 359 pciauto_postscan_setup_cardbus_bridge(struct pci_channel *hose,
 360                         int top_bus,
 361                         int current_bus,
 362                         int pci_devfn,
 363                         int sub_bus)
 364 {
 365         u32 temp;
 366
 367         /*
 368          * [jsun] we always bump up baselines a little, so that if there
 369          * nothing behind P2P bridge, we don't wind up overlapping IO/MEM
 370          * spaces.
 371          */
 372         pciauto_lower_memspc += 1;
 373         pciauto_lower_iospc += 1;
 374
 375         /*
 376          * Configure subordinate bus number.  The PCI subsystem
 377          * bus scan will renumber buses (reserving three additional
 378          * for this PCI<->CardBus bridge for the case where a CardBus
 379          * adapter contains a P2P or CB2CB bridge.
 380          */
 381
 382         early_write_config_byte(hose, top_bus, current_bus, pci_devfn,
 383                                 PCI_SUBORDINATE_BUS, sub_bus);
 384
 385         /*
 386          * Reserve an additional 4MB for mem space and 16KB for
 387          * I/O space.  This should cover any additional space
 388          * requirement of unusual CardBus devices with
 389          * additional bridges that can consume more address space.
 390          *
 391          * Although pcmcia-cs currently will reprogram bridge
 392          * windows, the goal is to add an option to leave them
 393          * alone and use the bridge window ranges as the regions
 394          * that are searched for free resources upon hot-insertion
 395          * of a device.  This will allow a PCI<->CardBus bridge
 396          * configured by this routine to happily live behind a
 397          * P2P bridge in a system.
 398          */
 399         /* Align memory and I/O to 4KB and 4 byte boundaries. */
 400         pciauto_lower_memspc = (pciauto_lower_memspc + (0x1000 - 1))
 401                 & ~(0x1000 - 1);
 402         pciauto_lower_iospc = (pciauto_lower_iospc + (0x4 - 1))
 403                 & ~(0x4 - 1);
 404         /* Set up memory and I/O filter limits, assume 32-bit I/O space */
 405         early_write_config_dword(hose, top_bus, current_bus, pci_devfn,
 406                 PCI_CB_MEMORY_LIMIT_0, pciauto_lower_memspc - 1);
 407         early_write_config_dword(hose, top_bus, current_bus, pci_devfn,
 408                 PCI_CB_IO_LIMIT_0, pciauto_lower_iospc - 1);
 409
 410         /* Enable memory and I/O accesses, enable bus master */
 411         early_read_config_dword(hose, top_bus, current_bus, pci_devfn,
 412                 PCI_COMMAND, &temp);
 413         early_write_config_dword(hose, top_bus, current_bus, pci_devfn,
 414                 PCI_COMMAND, temp | PCI_COMMAND_IO | PCI_COMMAND_MEMORY |
 415                 PCI_COMMAND_MASTER);
 416 }
 417
 418 #define PCIAUTO_IDE_MODE_MASK           0x05
 419
 420 static int __init
 421 pciauto_bus_scan(struct pci_channel *hose, int top_bus, int current_bus)
 422 {
 423         int sub_bus;
 424         u32 pci_devfn, pci_class, cmdstat, found_multi=0;
 425         unsigned short vid, did;
 426         unsigned char header_type;
 427         int devfn_start = 0;
 428         int devfn_stop = 0xff;
 429
 430         sub_bus = current_bus;
 431
 432         if (hose->first_devfn)
 433                 devfn_start = hose->first_devfn;
 434         if (hose->last_devfn)
 435                 devfn_stop = hose->last_devfn;
 436
 437         for (pci_devfn=devfn_start; pci_devfn<devfn_stop; pci_devfn++) {
 438
 439                 if (PCI_FUNC(pci_devfn) && !found_multi)
 440                         continue;
 441
 442                 early_read_config_word(hose, top_bus, current_bus, pci_devfn,
 443                                        PCI_VENDOR_ID, &vid);
 444
 445                 if (vid == 0xffff) continue;
 446
 447                 early_read_config_byte(hose, top_bus, current_bus, pci_devfn,
 448                                        PCI_HEADER_TYPE, &header_type);
 449
 450                 if (!PCI_FUNC(pci_devfn))
 451                         found_multi = header_type & 0x80;
 452
 453                 early_read_config_word(hose, top_bus, current_bus, pci_devfn,
 454                                        PCI_DEVICE_ID, &did);
 455
 456                 early_read_config_dword(hose, top_bus, current_bus, pci_devfn,
 457                                         PCI_CLASS_REVISION, &pci_class);
 458
 459                 DBG("%.2x:%.2x.%x Class %.4x: %.4x:%.4x",
 460                         current_bus, PCI_SLOT(pci_devfn), PCI_FUNC(pci_devfn),
 461                         pci_class >> 16, vid, did);
 462                 if (pci_class & 0xff)
 463                         DBG(" (rev %.2x)", pci_class & 0xff);
 464                 DBG("\n");
 465
 466                 if ((pci_class >> 16) == PCI_CLASS_BRIDGE_PCI) {
 467                         DBG("        Bridge: primary=%.2x, secondary=%.2x\n",
 468                                 current_bus, sub_bus + 1);
 469                         pciauto_prescan_setup_bridge(hose, top_bus, current_bus,
 470                                                      pci_devfn, sub_bus);
 471                         DBG("Scanning sub bus %.2x, I/O 0x%.8x, Mem 0x%.8x\n",
 472                                 sub_bus + 1,
 473                                 pciauto_lower_iospc, pciauto_lower_memspc);
 474                         sub_bus = pciauto_bus_scan(hose, top_bus, sub_bus+1);
 475                         DBG("Back to bus %.2x\n", current_bus);
 476                         pciauto_postscan_setup_bridge(hose, top_bus, current_bus,
 477                                                         pci_devfn, sub_bus);
 478                         continue;
 479                 } else if ((pci_class >> 16) == PCI_CLASS_BRIDGE_CARDBUS) {
 480                         DBG("  CARDBUS  Bridge: primary=%.2x, secondary=%.2x\n",
 481                                 current_bus, sub_bus + 1);
 482                         DBG("PCI Autoconfig: Found CardBus bridge, device %d function %d\n", PCI_SLOT(pci_devfn), PCI_FUNC(pci_devfn));
 483                         /* Place CardBus Socket/ExCA registers */
 484                         pciauto_setup_bars(hose, top_bus, current_bus, pci_devfn, PCI_BASE_ADDRESS_0);
 485
 486                         pciauto_prescan_setup_cardbus_bridge(hose, top_bus,
 487                                         current_bus, pci_devfn, sub_bus);
 488
 489                         DBG("Scanning sub bus %.2x, I/O 0x%.8x, Mem 0x%.8x\n",
 490                                 sub_bus + 1,
 491                                 pciauto_lower_iospc, pciauto_lower_memspc);
 492                         sub_bus = pciauto_bus_scan(hose, top_bus, sub_bus+1);
 493                         DBG("Back to bus %.2x, sub_bus is %x\n", current_bus, sub_bus);
 494                         pciauto_postscan_setup_cardbus_bridge(hose, top_bus,
 495                                         current_bus, pci_devfn, sub_bus);
 496                         continue;
 497                 } else if ((pci_class >> 16) == PCI_CLASS_STORAGE_IDE) {
 498
 499                         unsigned char prg_iface;
 500
 501                         early_read_config_byte(hose, top_bus, current_bus,
 502                                 pci_devfn, PCI_CLASS_PROG, &prg_iface);
 503                         if (!(prg_iface & PCIAUTO_IDE_MODE_MASK)) {
 504                                 DBG("Skipping legacy mode IDE controller\n");
 505                                 continue;
 506                         }
 507                 }
 508
 509                 /*
 510                  * Found a peripheral, enable some standard
 511                  * settings
 512                  */
 513                 early_read_config_dword(hose, top_bus, current_bus, pci_devfn,
 514                                         PCI_COMMAND, &cmdstat);
 515                 early_write_config_dword(hose, top_bus, current_bus, pci_devfn,
 516                                          PCI_COMMAND, cmdstat | PCI_COMMAND_IO |
 517                                          PCI_COMMAND_MEMORY |
 518                                          PCI_COMMAND_MASTER);
 519                 early_write_config_byte(hose, top_bus, current_bus, pci_devfn,
 520                                         PCI_LATENCY_TIMER, 0x80);
 521
 522                 /* Allocate PCI I/O and/or memory space */
 523                 pciauto_setup_bars(hose, top_bus, current_bus, pci_devfn, PCI_BASE_ADDRESS_5);
 524         }
 525         return sub_bus;
 526 }
 527
 528 int __init
 529 pciauto_assign_resources(int busno, struct pci_channel *hose)
 530 {
 531         /* setup resource limits */
 532         io_resource_inuse = hose->io_resource;
 533         mem_resource_inuse = hose->mem_resource;
 534
 535         pciauto_lower_iospc = io_resource_inuse->start;
 536         pciauto_upper_iospc = io_resource_inuse->end + 1;
 537         pciauto_lower_memspc = mem_resource_inuse->start;
 538         pciauto_upper_memspc = mem_resource_inuse->end + 1;
 539         DBG("Autoconfig PCI channel 0x%p\n", hose);
 540         DBG("Scanning bus %.2x, I/O 0x%.8x:0x%.8x, Mem 0x%.8x:0x%.8x\n",
 541                 busno, pciauto_lower_iospc, pciauto_upper_iospc,
 542                 pciauto_lower_memspc, pciauto_upper_memspc);
 543
 544         return pciauto_bus_scan(hose, busno, busno);
 545 }