drivers/pci/hotplug/cpqphp_nvram.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Compaq Hot Plug Controller Driver
   4  *
   5  * Copyright (C) 1995,2001 Compaq Computer Corporation
   6  * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
   7  * Copyright (C) 2001 IBM Corp.
   8  *
   9  * All rights reserved.
  10  *
  11  * Send feedback to <greg@kroah.com>
  12  *
  13  */
  14
  15 #include <linux/module.h>
  16 #include <linux/kernel.h>
  17 #include <linux/types.h>
  18 #include <linux/proc_fs.h>
  19 #include <linux/slab.h>
  20 #include <linux/workqueue.h>
  21 #include <linux/pci.h>
  22 #include <linux/pci_hotplug.h>
  23 #include <linux/uaccess.h>
  24 #include "cpqphp.h"
  25 #include "cpqphp_nvram.h"
  26
  27
  28 #define ROM_INT15_PHY_ADDR              0x0FF859
  29 #define READ_EV                         0xD8A4
  30 #define WRITE_EV                        0xD8A5
  31
  32 struct register_foo {
  33         union {
  34                 unsigned long lword;            /* eax */
  35                 unsigned short word;            /* ax */
  36
  37                 struct {
  38                         unsigned char low;      /* al */
  39                         unsigned char high;     /* ah */
  40                 } byte;
  41         } data;
  42
  43         unsigned char opcode;   /* see below */
  44         unsigned long length;   /* if the reg. is a pointer, how much data */
  45 } __attribute__ ((packed));
  46
  47 struct all_reg {
  48         struct register_foo eax_reg;
  49         struct register_foo ebx_reg;
  50         struct register_foo ecx_reg;
  51         struct register_foo edx_reg;
  52         struct register_foo edi_reg;
  53         struct register_foo esi_reg;
  54         struct register_foo eflags_reg;
  55 } __attribute__ ((packed));
  56
  57
  58 struct ev_hrt_header {
  59         u8 Version;
  60         u8 num_of_ctrl;
  61         u8 next;
  62 };
  63
  64 struct ev_hrt_ctrl {
  65         u8 bus;
  66         u8 device;
  67         u8 function;
  68         u8 mem_avail;
  69         u8 p_mem_avail;
  70         u8 io_avail;
  71         u8 bus_avail;
  72         u8 next;
  73 };
  74
  75
  76 static u8 evbuffer_init;
  77 static u8 evbuffer_length;
  78 static u8 evbuffer[1024];
  79
  80 static void __iomem *compaq_int15_entry_point;
  81
  82 /* lock for ordering int15_bios_call() */
  83 static spinlock_t int15_lock;
  84
  85
  86 /* This is a series of function that deals with
  87  * setting & getting the hotplug resource table in some environment variable.
  88  */
  89
  90 /*
  91  * We really shouldn't be doing this unless there is a _very_ good reason to!!!
  92  * greg k-h
  93  */
  94
  95
  96 static u32 add_byte(u32 **p_buffer, u8 value, u32 *used, u32 *avail)
  97 {
  98         u8 **tByte;
  99
 100         if ((*used + 1) > *avail)
 101                 return(1);
 102
 103         *((u8 *)*p_buffer) = value;
 104         tByte = (u8 **)p_buffer;
 105         (*tByte)++;
 106         *used += 1;
 107         return(0);
 108 }
 109
 110
 111 static u32 add_dword(u32 **p_buffer, u32 value, u32 *used, u32 *avail)
 112 {
 113         if ((*used + 4) > *avail)
 114                 return(1);
 115
 116         **p_buffer = value;
 117         (*p_buffer)++;
 118         *used += 4;
 119         return(0);
 120 }
 121
 122
 123 /*
 124  * check_for_compaq_ROM
 125  *
 126  * this routine verifies that the ROM OEM string is 'COMPAQ'
 127  *
 128  * returns 0 for non-Compaq ROM, 1 for Compaq ROM
 129  */
 130 static int check_for_compaq_ROM(void __iomem *rom_start)
 131 {
 132         u8 temp1, temp2, temp3, temp4, temp5, temp6;
 133         int result = 0;
 134
 135         temp1 = readb(rom_start + 0xffea + 0);
 136         temp2 = readb(rom_start + 0xffea + 1);
 137         temp3 = readb(rom_start + 0xffea + 2);
 138         temp4 = readb(rom_start + 0xffea + 3);
 139         temp5 = readb(rom_start + 0xffea + 4);
 140         temp6 = readb(rom_start + 0xffea + 5);
 141         if ((temp1 == 'C') &&
 142             (temp2 == 'O') &&
 143             (temp3 == 'M') &&
 144             (temp4 == 'P') &&
 145             (temp5 == 'A') &&
 146             (temp6 == 'Q')) {
 147                 result = 1;
 148         }
 149         dbg("%s - returned %d\n", __func__, result);
 150         return result;
 151 }
 152
 153
 154 static u32 access_EV(u16 operation, u8 *ev_name, u8 *buffer, u32 *buf_size)
 155 {
 156         unsigned long flags;
 157         int op = operation;
 158         int ret_val;
 159
 160         if (!compaq_int15_entry_point)
 161                 return -ENODEV;
 162
 163         spin_lock_irqsave(&int15_lock, flags);
 164         __asm__ (
 165                 "xorl   %%ebx,%%ebx\n" \
 166                 "xorl    %%edx,%%edx\n" \
 167                 "pushf\n" \
 168                 "push %%cs\n" \
 169                 "cli\n" \
 170                 "call *%6\n"
 171                 : "=c" (*buf_size), "=a" (ret_val)
 172                 : "a" (op), "c" (*buf_size), "S" (ev_name),
 173                 "D" (buffer), "m" (compaq_int15_entry_point)
 174                 : "%ebx", "%edx");
 175         spin_unlock_irqrestore(&int15_lock, flags);
 176
 177         return((ret_val & 0xFF00) >> 8);
 178 }
 179
 180
 181 /*
 182  * load_HRT
 183  *
 184  * Read the hot plug Resource Table from NVRAM
 185  */
 186 static int load_HRT(void __iomem *rom_start)
 187 {
 188         u32 available;
 189         u32 temp_dword;
 190         u8 temp_byte = 0xFF;
 191         u32 rc;
 192
 193         if (!check_for_compaq_ROM(rom_start))
 194                 return -ENODEV;
 195
 196         available = 1024;
 197
 198         /* Now load the EV */
 199         temp_dword = available;
 200
 201         rc = access_EV(READ_EV, "CQTHPS", evbuffer, &temp_dword);
 202
 203         evbuffer_length = temp_dword;
 204
 205         /* We're maintaining the resource lists so write FF to invalidate old
 206          * info
 207          */
 208         temp_dword = 1;
 209
 210         rc = access_EV(WRITE_EV, "CQTHPS", &temp_byte, &temp_dword);
 211
 212         return rc;
 213 }
 214
 215
 216 /*
 217  * store_HRT
 218  *
 219  * Save the hot plug Resource Table in NVRAM
 220  */
 221 static u32 store_HRT(void __iomem *rom_start)
 222 {
 223         u32 *buffer;
 224         u32 *pFill;
 225         u32 usedbytes;
 226         u32 available;
 227         u32 temp_dword;
 228         u32 rc;
 229         u8 loop;
 230         u8 numCtrl = 0;
 231         struct controller *ctrl;
 232         struct pci_resource *resNode;
 233         struct ev_hrt_header *p_EV_header;
 234         struct ev_hrt_ctrl *p_ev_ctrl;
 235
 236         available = 1024;
 237
 238         if (!check_for_compaq_ROM(rom_start))
 239                 return(1);
 240
 241         buffer = (u32 *) evbuffer;
 242
 243         if (!buffer)
 244                 return(1);
 245
 246         pFill = buffer;
 247         usedbytes = 0;
 248
 249         p_EV_header = (struct ev_hrt_header *) pFill;
 250
 251         ctrl = cpqhp_ctrl_list;
 252
 253         /* The revision of this structure */
 254         rc = add_byte(&pFill, 1 + ctrl->push_flag, &usedbytes, &available);
 255         if (rc)
 256                 return(rc);
 257
 258         /* The number of controllers */
 259         rc = add_byte(&pFill, 1, &usedbytes, &available);
 260         if (rc)
 261                 return(rc);
 262
 263         while (ctrl) {
 264                 p_ev_ctrl = (struct ev_hrt_ctrl *) pFill;
 265
 266                 numCtrl++;
 267
 268                 /* The bus number */
 269                 rc = add_byte(&pFill, ctrl->bus, &usedbytes, &available);
 270                 if (rc)
 271                         return(rc);
 272
 273                 /* The device Number */
 274                 rc = add_byte(&pFill, PCI_SLOT(ctrl->pci_dev->devfn), &usedbytes, &available);
 275                 if (rc)
 276                         return(rc);
 277
 278                 /* The function Number */
 279                 rc = add_byte(&pFill, PCI_FUNC(ctrl->pci_dev->devfn), &usedbytes, &available);
 280                 if (rc)
 281                         return(rc);
 282
 283                 /* Skip the number of available entries */
 284                 rc = add_dword(&pFill, 0, &usedbytes, &available);
 285                 if (rc)
 286                         return(rc);
 287
 288                 /* Figure out memory Available */
 289
 290                 resNode = ctrl->mem_head;
 291
 292                 loop = 0;
 293
 294                 while (resNode) {
 295                         loop++;
 296
 297                         /* base */
 298                         rc = add_dword(&pFill, resNode->base, &usedbytes, &available);
 299                         if (rc)
 300                                 return(rc);
 301
 302                         /* length */
 303                         rc = add_dword(&pFill, resNode->length, &usedbytes, &available);
 304                         if (rc)
 305                                 return(rc);
 306
 307                         resNode = resNode->next;
 308                 }
 309
 310                 /* Fill in the number of entries */
 311                 p_ev_ctrl->mem_avail = loop;
 312
 313                 /* Figure out prefetchable memory Available */
 314
 315                 resNode = ctrl->p_mem_head;
 316
 317                 loop = 0;
 318
 319                 while (resNode) {
 320                         loop++;
 321
 322                         /* base */
 323                         rc = add_dword(&pFill, resNode->base, &usedbytes, &available);
 324                         if (rc)
 325                                 return(rc);
 326
 327                         /* length */
 328                         rc = add_dword(&pFill, resNode->length, &usedbytes, &available);
 329                         if (rc)
 330                                 return(rc);
 331
 332                         resNode = resNode->next;
 333                 }
 334
 335                 /* Fill in the number of entries */
 336                 p_ev_ctrl->p_mem_avail = loop;
 337
 338                 /* Figure out IO Available */
 339
 340                 resNode = ctrl->io_head;
 341
 342                 loop = 0;
 343
 344                 while (resNode) {
 345                         loop++;
 346
 347                         /* base */
 348                         rc = add_dword(&pFill, resNode->base, &usedbytes, &available);
 349                         if (rc)
 350                                 return(rc);
 351
 352                         /* length */
 353                         rc = add_dword(&pFill, resNode->length, &usedbytes, &available);
 354                         if (rc)
 355                                 return(rc);
 356
 357                         resNode = resNode->next;
 358                 }
 359
 360                 /* Fill in the number of entries */
 361                 p_ev_ctrl->io_avail = loop;
 362
 363                 /* Figure out bus Available */
 364
 365                 resNode = ctrl->bus_head;
 366
 367                 loop = 0;
 368
 369                 while (resNode) {
 370                         loop++;
 371
 372                         /* base */
 373                         rc = add_dword(&pFill, resNode->base, &usedbytes, &available);
 374                         if (rc)
 375                                 return(rc);
 376
 377                         /* length */
 378                         rc = add_dword(&pFill, resNode->length, &usedbytes, &available);
 379                         if (rc)
 380                                 return(rc);
 381
 382                         resNode = resNode->next;
 383                 }
 384
 385                 /* Fill in the number of entries */
 386                 p_ev_ctrl->bus_avail = loop;
 387
 388                 ctrl = ctrl->next;
 389         }
 390
 391         p_EV_header->num_of_ctrl = numCtrl;
 392
 393         /* Now store the EV */
 394
 395         temp_dword = usedbytes;
 396
 397         rc = access_EV(WRITE_EV, "CQTHPS", (u8 *) buffer, &temp_dword);
 398
 399         dbg("usedbytes = 0x%x, length = 0x%x\n", usedbytes, temp_dword);
 400
 401         evbuffer_length = temp_dword;
 402
 403         if (rc) {
 404                 err(msg_unable_to_save);
 405                 return(1);
 406         }
 407
 408         return(0);
 409 }
 410
 411
 412 void compaq_nvram_init(void __iomem *rom_start)
 413 {
 414         if (rom_start)
 415                 compaq_int15_entry_point = (rom_start + ROM_INT15_PHY_ADDR - ROM_PHY_ADDR);
 416
 417         dbg("int15 entry  = %p\n", compaq_int15_entry_point);
 418
 419         /* initialize our int15 lock */
 420         spin_lock_init(&int15_lock);
 421 }
 422
 423
 424 int compaq_nvram_load(void __iomem *rom_start, struct controller *ctrl)
 425 {
 426         u8 bus, device, function;
 427         u8 nummem, numpmem, numio, numbus;
 428         u32 rc;
 429         u8 *p_byte;
 430         struct pci_resource *mem_node;
 431         struct pci_resource *p_mem_node;
 432         struct pci_resource *io_node;
 433         struct pci_resource *bus_node;
 434         struct ev_hrt_ctrl *p_ev_ctrl;
 435         struct ev_hrt_header *p_EV_header;
 436
 437         if (!evbuffer_init) {
 438                 /* Read the resource list information in from NVRAM */
 439                 if (load_HRT(rom_start))
 440                         memset(evbuffer, 0, 1024);
 441
 442                 evbuffer_init = 1;
 443         }
 444
 445         /* If we saved information in NVRAM, use it now */
 446         p_EV_header = (struct ev_hrt_header *) evbuffer;
 447
 448         /* The following code is for systems where version 1.0 of this
 449          * driver has been loaded, but doesn't support the hardware.
 450          * In that case, the driver would incorrectly store something
 451          * in NVRAM.
 452          */
 453         if ((p_EV_header->Version == 2) ||
 454             ((p_EV_header->Version == 1) && !ctrl->push_flag)) {
 455                 p_byte = &(p_EV_header->next);
 456
 457                 p_ev_ctrl = (struct ev_hrt_ctrl *) &(p_EV_header->next);
 458
 459                 p_byte += 3;
 460
 461                 if (p_byte > ((u8 *)p_EV_header + evbuffer_length))
 462                         return 2;
 463
 464                 bus = p_ev_ctrl->bus;
 465                 device = p_ev_ctrl->device;
 466                 function = p_ev_ctrl->function;
 467
 468                 while ((bus != ctrl->bus) ||
 469                        (device != PCI_SLOT(ctrl->pci_dev->devfn)) ||
 470                        (function != PCI_FUNC(ctrl->pci_dev->devfn))) {
 471                         nummem = p_ev_ctrl->mem_avail;
 472                         numpmem = p_ev_ctrl->p_mem_avail;
 473                         numio = p_ev_ctrl->io_avail;
 474                         numbus = p_ev_ctrl->bus_avail;
 475
 476                         p_byte += 4;
 477
 478                         if (p_byte > ((u8 *)p_EV_header + evbuffer_length))
 479                                 return 2;
 480
 481                         /* Skip forward to the next entry */
 482                         p_byte += (nummem + numpmem + numio + numbus) * 8;
 483
 484                         if (p_byte > ((u8 *)p_EV_header + evbuffer_length))
 485                                 return 2;
 486
 487                         p_ev_ctrl = (struct ev_hrt_ctrl *) p_byte;
 488
 489                         p_byte += 3;
 490
 491                         if (p_byte > ((u8 *)p_EV_header + evbuffer_length))
 492                                 return 2;
 493
 494                         bus = p_ev_ctrl->bus;
 495                         device = p_ev_ctrl->device;
 496                         function = p_ev_ctrl->function;
 497                 }
 498
 499                 nummem = p_ev_ctrl->mem_avail;
 500                 numpmem = p_ev_ctrl->p_mem_avail;
 501                 numio = p_ev_ctrl->io_avail;
 502                 numbus = p_ev_ctrl->bus_avail;
 503
 504                 p_byte += 4;
 505
 506                 if (p_byte > ((u8 *)p_EV_header + evbuffer_length))
 507                         return 2;
 508
 509                 while (nummem--) {
 510                         mem_node = kmalloc(sizeof(struct pci_resource), GFP_KERNEL);
 511
 512                         if (!mem_node)
 513                                 break;
 514
 515                         mem_node->base = *(u32 *)p_byte;
 516                         dbg("mem base = %8.8x\n", mem_node->base);
 517                         p_byte += 4;
 518
 519                         if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
 520                                 kfree(mem_node);
 521                                 return 2;
 522                         }
 523
 524                         mem_node->length = *(u32 *)p_byte;
 525                         dbg("mem length = %8.8x\n", mem_node->length);
 526                         p_byte += 4;
 527
 528                         if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
 529                                 kfree(mem_node);
 530                                 return 2;
 531                         }
 532
 533                         mem_node->next = ctrl->mem_head;
 534                         ctrl->mem_head = mem_node;
 535                 }
 536
 537                 while (numpmem--) {
 538                         p_mem_node = kmalloc(sizeof(struct pci_resource), GFP_KERNEL);
 539
 540                         if (!p_mem_node)
 541                                 break;
 542
 543                         p_mem_node->base = *(u32 *)p_byte;
 544                         dbg("pre-mem base = %8.8x\n", p_mem_node->base);
 545                         p_byte += 4;
 546
 547                         if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
 548                                 kfree(p_mem_node);
 549                                 return 2;
 550                         }
 551
 552                         p_mem_node->length = *(u32 *)p_byte;
 553                         dbg("pre-mem length = %8.8x\n", p_mem_node->length);
 554                         p_byte += 4;
 555
 556                         if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
 557                                 kfree(p_mem_node);
 558                                 return 2;
 559                         }
 560
 561                         p_mem_node->next = ctrl->p_mem_head;
 562                         ctrl->p_mem_head = p_mem_node;
 563                 }
 564
 565                 while (numio--) {
 566                         io_node = kmalloc(sizeof(struct pci_resource), GFP_KERNEL);
 567
 568                         if (!io_node)
 569                                 break;
 570
 571                         io_node->base = *(u32 *)p_byte;
 572                         dbg("io base = %8.8x\n", io_node->base);
 573                         p_byte += 4;
 574
 575                         if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
 576                                 kfree(io_node);
 577                                 return 2;
 578                         }
 579
 580                         io_node->length = *(u32 *)p_byte;
 581                         dbg("io length = %8.8x\n", io_node->length);
 582                         p_byte += 4;
 583
 584                         if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
 585                                 kfree(io_node);
 586                                 return 2;
 587                         }
 588
 589                         io_node->next = ctrl->io_head;
 590                         ctrl->io_head = io_node;
 591                 }
 592
 593                 while (numbus--) {
 594                         bus_node = kmalloc(sizeof(struct pci_resource), GFP_KERNEL);
 595
 596                         if (!bus_node)
 597                                 break;
 598
 599                         bus_node->base = *(u32 *)p_byte;
 600                         p_byte += 4;
 601
 602                         if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
 603                                 kfree(bus_node);
 604                                 return 2;
 605                         }
 606
 607                         bus_node->length = *(u32 *)p_byte;
 608                         p_byte += 4;
 609
 610                         if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
 611                                 kfree(bus_node);
 612                                 return 2;
 613                         }
 614
 615                         bus_node->next = ctrl->bus_head;
 616                         ctrl->bus_head = bus_node;
 617                 }
 618
 619                 /* If all of the following fail, we don't have any resources for
 620                  * hot plug add
 621                  */
 622                 rc = 1;
 623                 rc &= cpqhp_resource_sort_and_combine(&(ctrl->mem_head));
 624                 rc &= cpqhp_resource_sort_and_combine(&(ctrl->p_mem_head));
 625                 rc &= cpqhp_resource_sort_and_combine(&(ctrl->io_head));
 626                 rc &= cpqhp_resource_sort_and_combine(&(ctrl->bus_head));
 627
 628                 if (rc)
 629                         return(rc);
 630         } else {
 631                 if ((evbuffer[0] != 0) && (!ctrl->push_flag))
 632                         return 1;
 633         }
 634
 635         return 0;
 636 }
 637
 638
 639 int compaq_nvram_store(void __iomem *rom_start)
 640 {
 641         int rc = 1;
 642
 643         if (rom_start == NULL)
 644                 return -ENODEV;
 645
 646         if (evbuffer_init) {
 647                 rc = store_HRT(rom_start);
 648                 if (rc)
 649                         err(msg_unable_to_save);
 650         }
 651         return rc;
 652 }
 653