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 DEFINE_SPINLOCK(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
 420
 421 int compaq_nvram_load(void __iomem *rom_start, struct controller *ctrl)
 422 {
 423         u8 bus, device, function;
 424         u8 nummem, numpmem, numio, numbus;
 425         u32 rc;
 426         u8 *p_byte;
 427         struct pci_resource *mem_node;
 428         struct pci_resource *p_mem_node;
 429         struct pci_resource *io_node;
 430         struct pci_resource *bus_node;
 431         struct ev_hrt_ctrl *p_ev_ctrl;
 432         struct ev_hrt_header *p_EV_header;
 433
 434         if (!evbuffer_init) {
 435                 /* Read the resource list information in from NVRAM */
 436                 if (load_HRT(rom_start))
 437                         memset(evbuffer, 0, 1024);
 438
 439                 evbuffer_init = 1;
 440         }
 441
 442         /* If we saved information in NVRAM, use it now */
 443         p_EV_header = (struct ev_hrt_header *) evbuffer;
 444
 445         /* The following code is for systems where version 1.0 of this
 446          * driver has been loaded, but doesn't support the hardware.
 447          * In that case, the driver would incorrectly store something
 448          * in NVRAM.
 449          */
 450         if ((p_EV_header->Version == 2) ||
 451             ((p_EV_header->Version == 1) && !ctrl->push_flag)) {
 452                 p_byte = &(p_EV_header->next);
 453
 454                 p_ev_ctrl = (struct ev_hrt_ctrl *) &(p_EV_header->next);
 455
 456                 p_byte += 3;
 457
 458                 if (p_byte > ((u8 *)p_EV_header + evbuffer_length))
 459                         return 2;
 460
 461                 bus = p_ev_ctrl->bus;
 462                 device = p_ev_ctrl->device;
 463                 function = p_ev_ctrl->function;
 464
 465                 while ((bus != ctrl->bus) ||
 466                        (device != PCI_SLOT(ctrl->pci_dev->devfn)) ||
 467                        (function != PCI_FUNC(ctrl->pci_dev->devfn))) {
 468                         nummem = p_ev_ctrl->mem_avail;
 469                         numpmem = p_ev_ctrl->p_mem_avail;
 470                         numio = p_ev_ctrl->io_avail;
 471                         numbus = p_ev_ctrl->bus_avail;
 472
 473                         p_byte += 4;
 474
 475                         if (p_byte > ((u8 *)p_EV_header + evbuffer_length))
 476                                 return 2;
 477
 478                         /* Skip forward to the next entry */
 479                         p_byte += (nummem + numpmem + numio + numbus) * 8;
 480
 481                         if (p_byte > ((u8 *)p_EV_header + evbuffer_length))
 482                                 return 2;
 483
 484                         p_ev_ctrl = (struct ev_hrt_ctrl *) p_byte;
 485
 486                         p_byte += 3;
 487
 488                         if (p_byte > ((u8 *)p_EV_header + evbuffer_length))
 489                                 return 2;
 490
 491                         bus = p_ev_ctrl->bus;
 492                         device = p_ev_ctrl->device;
 493                         function = p_ev_ctrl->function;
 494                 }
 495
 496                 nummem = p_ev_ctrl->mem_avail;
 497                 numpmem = p_ev_ctrl->p_mem_avail;
 498                 numio = p_ev_ctrl->io_avail;
 499                 numbus = p_ev_ctrl->bus_avail;
 500
 501                 p_byte += 4;
 502
 503                 if (p_byte > ((u8 *)p_EV_header + evbuffer_length))
 504                         return 2;
 505
 506                 while (nummem--) {
 507                         mem_node = kmalloc(sizeof(struct pci_resource), GFP_KERNEL);
 508
 509                         if (!mem_node)
 510                                 break;
 511
 512                         mem_node->base = *(u32 *)p_byte;
 513                         dbg("mem base = %8.8x\n", mem_node->base);
 514                         p_byte += 4;
 515
 516                         if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
 517                                 kfree(mem_node);
 518                                 return 2;
 519                         }
 520
 521                         mem_node->length = *(u32 *)p_byte;
 522                         dbg("mem length = %8.8x\n", mem_node->length);
 523                         p_byte += 4;
 524
 525                         if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
 526                                 kfree(mem_node);
 527                                 return 2;
 528                         }
 529
 530                         mem_node->next = ctrl->mem_head;
 531                         ctrl->mem_head = mem_node;
 532                 }
 533
 534                 while (numpmem--) {
 535                         p_mem_node = kmalloc(sizeof(struct pci_resource), GFP_KERNEL);
 536
 537                         if (!p_mem_node)
 538                                 break;
 539
 540                         p_mem_node->base = *(u32 *)p_byte;
 541                         dbg("pre-mem base = %8.8x\n", p_mem_node->base);
 542                         p_byte += 4;
 543
 544                         if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
 545                                 kfree(p_mem_node);
 546                                 return 2;
 547                         }
 548
 549                         p_mem_node->length = *(u32 *)p_byte;
 550                         dbg("pre-mem length = %8.8x\n", p_mem_node->length);
 551                         p_byte += 4;
 552
 553                         if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
 554                                 kfree(p_mem_node);
 555                                 return 2;
 556                         }
 557
 558                         p_mem_node->next = ctrl->p_mem_head;
 559                         ctrl->p_mem_head = p_mem_node;
 560                 }
 561
 562                 while (numio--) {
 563                         io_node = kmalloc(sizeof(struct pci_resource), GFP_KERNEL);
 564
 565                         if (!io_node)
 566                                 break;
 567
 568                         io_node->base = *(u32 *)p_byte;
 569                         dbg("io base = %8.8x\n", io_node->base);
 570                         p_byte += 4;
 571
 572                         if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
 573                                 kfree(io_node);
 574                                 return 2;
 575                         }
 576
 577                         io_node->length = *(u32 *)p_byte;
 578                         dbg("io length = %8.8x\n", io_node->length);
 579                         p_byte += 4;
 580
 581                         if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
 582                                 kfree(io_node);
 583                                 return 2;
 584                         }
 585
 586                         io_node->next = ctrl->io_head;
 587                         ctrl->io_head = io_node;
 588                 }
 589
 590                 while (numbus--) {
 591                         bus_node = kmalloc(sizeof(struct pci_resource), GFP_KERNEL);
 592
 593                         if (!bus_node)
 594                                 break;
 595
 596                         bus_node->base = *(u32 *)p_byte;
 597                         p_byte += 4;
 598
 599                         if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
 600                                 kfree(bus_node);
 601                                 return 2;
 602                         }
 603
 604                         bus_node->length = *(u32 *)p_byte;
 605                         p_byte += 4;
 606
 607                         if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
 608                                 kfree(bus_node);
 609                                 return 2;
 610                         }
 611
 612                         bus_node->next = ctrl->bus_head;
 613                         ctrl->bus_head = bus_node;
 614                 }
 615
 616                 /* If all of the following fail, we don't have any resources for
 617                  * hot plug add
 618                  */
 619                 rc = 1;
 620                 rc &= cpqhp_resource_sort_and_combine(&(ctrl->mem_head));
 621                 rc &= cpqhp_resource_sort_and_combine(&(ctrl->p_mem_head));
 622                 rc &= cpqhp_resource_sort_and_combine(&(ctrl->io_head));
 623                 rc &= cpqhp_resource_sort_and_combine(&(ctrl->bus_head));
 624
 625                 if (rc)
 626                         return(rc);
 627         } else {
 628                 if ((evbuffer[0] != 0) && (!ctrl->push_flag))
 629                         return 1;
 630         }
 631
 632         return 0;
 633 }
 634
 635
 636 int compaq_nvram_store(void __iomem *rom_start)
 637 {
 638         int rc = 1;
 639
 640         if (rom_start == NULL)
 641                 return -ENODEV;
 642
 643         if (evbuffer_init) {
 644                 rc = store_HRT(rom_start);
 645                 if (rc)
 646                         err(msg_unable_to_save);
 647         }
 648         return rc;
 649 }
 650