src/mainboard/emulation/qemu-i440fx/fw_cfg.c

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 #include <endian.h>
   4 #include <stdlib.h>
   5 #include <string.h>
   6 #include <smbios.h>
   7 #include <console/console.h>
   8 #include <arch/io.h>
   9 #include <acpi/acpi.h>
  10 #include <commonlib/endian.h>
  11
  12 #include "fw_cfg.h"
  13 #include "fw_cfg_if.h"
  14
  15 #define FW_CFG_PORT_CTL       0x0510
  16 #define FW_CFG_PORT_DATA      0x0511
  17 #define FW_CFG_DMA_ADDR_HIGH  0x0514
  18 #define FW_CFG_DMA_ADDR_LOW   0x0518
  19
  20 static int fw_cfg_detected;
  21 static uint8_t fw_ver;
  22
  23 static void fw_cfg_dma(int control, void *buf, int len);
  24
  25 static int fw_cfg_present(void)
  26 {
  27         static const char qsig[] = "QEMU";
  28         unsigned char sig[FW_CFG_SIG_SIZE];
  29         int detected = 0;
  30
  31         if (fw_cfg_detected == 0) {
  32                 fw_cfg_get(FW_CFG_SIGNATURE, sig, sizeof(sig));
  33                 detected = memcmp(sig, qsig, FW_CFG_SIG_SIZE) == 0;
  34                 printk(BIOS_INFO, "QEMU: firmware config interface %s\n",
  35                                 detected ? "detected" : "not found");
  36                 if (detected) {
  37                         fw_cfg_get(FW_CFG_ID, &fw_ver, sizeof(fw_ver));
  38                         printk(BIOS_INFO, "Firmware config version id: %d\n", fw_ver);
  39                 }
  40                 fw_cfg_detected = detected + 1;
  41         }
  42         return fw_cfg_detected - 1;
  43 }
  44
  45 static void fw_cfg_select(uint16_t entry)
  46 {
  47         if (fw_ver & FW_CFG_VERSION_DMA)
  48                 fw_cfg_dma(FW_CFG_DMA_CTL_SELECT | entry << 16, NULL, 0);
  49         else
  50                 outw(entry, FW_CFG_PORT_CTL);
  51 }
  52
  53 static void fw_cfg_read(void *dst, int dstlen)
  54 {
  55         if (fw_ver & FW_CFG_VERSION_DMA)
  56                 fw_cfg_dma(FW_CFG_DMA_CTL_READ, dst, dstlen);
  57         else
  58                 insb(FW_CFG_PORT_DATA, dst, dstlen);
  59 }
  60
  61 void fw_cfg_get(uint16_t entry, void *dst, int dstlen)
  62 {
  63         fw_cfg_select(entry);
  64         fw_cfg_read(dst, dstlen);
  65 }
  66
  67 static int fw_cfg_find_file(FWCfgFile *file, const char *name)
  68 {
  69         uint32_t count = 0;
  70
  71         fw_cfg_select(FW_CFG_FILE_DIR);
  72         fw_cfg_read(&count, sizeof(count));
  73         count = be32_to_cpu(count);
  74
  75         for (int i = 0; i < count; i++) {
  76                 fw_cfg_read(file, sizeof(*file));
  77                 if (strcmp(file->name, name) == 0) {
  78                         file->size = be32_to_cpu(file->size);
  79                         file->select = be16_to_cpu(file->select);
  80                         printk(BIOS_INFO, "QEMU: firmware config: Found '%s'\n", name);
  81                         return 0;
  82                 }
  83         }
  84         printk(BIOS_INFO, "QEMU: firmware config: Couldn't find '%s'\n", name);
  85         return -1;
  86 }
  87
  88 int fw_cfg_check_file(FWCfgFile *file, const char *name)
  89 {
  90         if (!fw_cfg_present())
  91                 return -1;
  92         return fw_cfg_find_file(file, name);
  93 }
  94
  95 static int fw_cfg_e820_select(uint32_t *size)
  96 {
  97         FWCfgFile file;
  98
  99         if (!fw_cfg_present() || fw_cfg_find_file(&file, "etc/e820"))
 100                 return -1;
 101         fw_cfg_select(file.select);
 102         *size = file.size;
 103         return 0;
 104 }
 105
 106 static int fw_cfg_e820_read(FwCfgE820Entry *entry, uint32_t *size,
 107                 uint32_t *pos)
 108 {
 109         if (*pos + sizeof(*entry) > *size)
 110                 return -1;
 111
 112         fw_cfg_read(entry, sizeof(*entry));
 113         *pos += sizeof(*entry);
 114         return 0;
 115 }
 116
 117 /* returns tolud on success or 0 on failure */
 118 uintptr_t fw_cfg_tolud(void)
 119 {
 120         FwCfgE820Entry e;
 121         uint64_t top = 0;
 122         uint32_t size = 0, pos = 0;
 123
 124         if (fw_cfg_e820_select(&size) == 0) {
 125                 while (!fw_cfg_e820_read(&e, &size, &pos)) {
 126                         uint64_t limit = e.address + e.length;
 127                         if (e.type == 1 && limit < 4ULL * GiB && limit > top)
 128                                 top = limit;
 129                 }
 130         }
 131         return (uintptr_t)top;
 132 }
 133
 134 int fw_cfg_max_cpus(void)
 135 {
 136         unsigned short max_cpus;
 137
 138         if (!fw_cfg_present())
 139                 return 0;
 140
 141         fw_cfg_get(FW_CFG_MAX_CPUS, &max_cpus, sizeof(max_cpus));
 142         return max_cpus;
 143 }
 144
 145 /* ---------------------------------------------------------------------- */
 146
 147 /*
 148  * Starting with release 1.7 qemu provides ACPI tables via fw_cfg.
 149  * Main advantage is that new (virtual) hardware which needs acpi
 150  * support JustWorks[tm] without having to patch & update the firmware
 151  * (seabios, coreboot, ...) accordingly.
 152  *
 153  * Qemu provides a etc/table-loader file with instructions for the
 154  * firmware:
 155  *   - A "load" instruction to fetch ACPI data from fw_cfg.
 156  *   - A "pointer" instruction to patch a pointer.  This is needed to
 157  *     get table-to-table references right, it is basically a
 158  *     primitive dynamic linker for ACPI tables.
 159  *   - A "checksum" instruction to generate ACPI table checksums.
 160  *
 161  * If a etc/table-loader file is found we'll go try loading the acpi
 162  * tables from fw_cfg, otherwise we'll fallback to the ACPI tables
 163  * compiled in.
 164  */
 165
 166 #define BIOS_LINKER_LOADER_FILESZ 56
 167
 168 struct BiosLinkerLoaderEntry {
 169         uint32_t command;
 170         union {
 171                 /*
 172                  * COMMAND_ALLOCATE - allocate a table from @alloc.file
 173                  * subject to @alloc.align alignment (must be power of 2)
 174                  * and @alloc.zone (can be HIGH or FSEG) requirements.
 175                  *
 176                  * Must appear exactly once for each file, and before
 177                  * this file is referenced by any other command.
 178                  */
 179                 struct {
 180                         char file[BIOS_LINKER_LOADER_FILESZ];
 181                         uint32_t align;
 182                         uint8_t zone;
 183                 } alloc;
 184
 185                 /*
 186                  * COMMAND_ADD_POINTER - patch the table (originating from
 187                  * @dest_file) at @pointer.offset, by adding a pointer to the table
 188                  * originating from @src_file. 1,2,4 or 8 byte unsigned
 189                  * addition is used depending on @pointer.size.
 190                  */
 191                 struct {
 192                         char dest_file[BIOS_LINKER_LOADER_FILESZ];
 193                         char src_file[BIOS_LINKER_LOADER_FILESZ];
 194                         uint32_t offset;
 195                         uint8_t size;
 196                 } pointer;
 197
 198                 /*
 199                  * COMMAND_ADD_CHECKSUM - calculate checksum of the range specified by
 200                  * @cksum_start and @cksum_length fields,
 201                  * and then add the value at @cksum.offset.
 202                  * Checksum simply sums -X for each byte X in the range
 203                  * using 8-bit math.
 204                  */
 205                 struct {
 206                         char file[BIOS_LINKER_LOADER_FILESZ];
 207                         uint32_t offset;
 208                         uint32_t start;
 209                         uint32_t length;
 210                 } cksum;
 211
 212                 /* padding */
 213                 char pad[124];
 214         };
 215 } __packed;
 216 typedef struct BiosLinkerLoaderEntry BiosLinkerLoaderEntry;
 217
 218 enum {
 219         BIOS_LINKER_LOADER_COMMAND_ALLOCATE     = 0x1,
 220         BIOS_LINKER_LOADER_COMMAND_ADD_POINTER  = 0x2,
 221         BIOS_LINKER_LOADER_COMMAND_ADD_CHECKSUM = 0x3,
 222 };
 223
 224 enum {
 225         BIOS_LINKER_LOADER_ALLOC_ZONE_HIGH = 0x1,
 226         BIOS_LINKER_LOADER_ALLOC_ZONE_FSEG = 0x2,
 227 };
 228
 229 unsigned long fw_cfg_acpi_tables(unsigned long start)
 230 {
 231         FWCfgFile f;
 232         BiosLinkerLoaderEntry *s;
 233         unsigned long *addrs, current;
 234         uint8_t *ptr;
 235         int i, j, src, dst, max;
 236
 237         if (fw_cfg_check_file(&f, "etc/table-loader"))
 238                 return 0;
 239
 240         printk(BIOS_DEBUG, "QEMU: found ACPI tables in fw_cfg.\n");
 241
 242         max = f.size / sizeof(*s);
 243         s = malloc(f.size);
 244         addrs = malloc(max * sizeof(*addrs));
 245         fw_cfg_get(f.select, s, f.size);
 246
 247         current = start;
 248         for (i = 0; i < max && s[i].command != 0; i++) {
 249                 void *cksum_data;
 250                 uint32_t cksum;
 251                 uint32_t addr4;
 252                 uint64_t addr8;
 253                 switch (s[i].command) {
 254                 case BIOS_LINKER_LOADER_COMMAND_ALLOCATE:
 255                         current = ALIGN_UP(current, s[i].alloc.align);
 256                         if (fw_cfg_check_file(&f, s[i].alloc.file))
 257                                 goto err;
 258
 259                         printk(BIOS_DEBUG, "QEMU: loading \"%s\" to 0x%lx (len %d)\n",
 260                                s[i].alloc.file, current, f.size);
 261                         fw_cfg_get(f.select, (void *)current, f.size);
 262                         addrs[i] = current;
 263                         current += f.size;
 264                         break;
 265
 266                 case BIOS_LINKER_LOADER_COMMAND_ADD_POINTER:
 267                         src = -1; dst = -1;
 268                         for (j = 0; j < i; j++) {
 269                                 if (s[j].command != BIOS_LINKER_LOADER_COMMAND_ALLOCATE)
 270                                         continue;
 271                                 if (strcmp(s[j].alloc.file, s[i].pointer.dest_file) == 0)
 272                                         dst = j;
 273                                 if (strcmp(s[j].alloc.file, s[i].pointer.src_file) == 0)
 274                                         src = j;
 275                         }
 276                         if (src == -1 || dst == -1)
 277                                 goto err;
 278
 279                         switch (s[i].pointer.size) {
 280                         case 4:
 281                                 ptr = (uint8_t *)addrs[dst];
 282                                 ptr += s[i].pointer.offset;
 283                                 addr4 = read_le32(ptr);
 284                                 addr4 += addrs[src];
 285                                 write_le32(ptr, addr4);
 286                                 break;
 287
 288                         case 8:
 289                                 ptr = (uint8_t *)addrs[dst];
 290                                 ptr += s[i].pointer.offset;
 291                                 addr8 = read_le64(ptr);
 292                                 addr8 += addrs[src];
 293                                 write_le64(ptr, addr8);
 294                                 break;
 295
 296                         default:
 297                                 /*
 298                                  * Should not happen.  ACPI knows 1 and 2 byte ptrs
 299                                  * too, but we are operating with 32bit offsets which
 300                                  * would simply not fit in there ...
 301                                  */
 302                                 printk(BIOS_DEBUG, "QEMU: acpi: unimplemented ptr size %d\n",
 303                                        s[i].pointer.size);
 304                                 goto err;
 305                         }
 306                         break;
 307
 308                 case BIOS_LINKER_LOADER_COMMAND_ADD_CHECKSUM:
 309                         dst = -1;
 310                         for (j = 0; j < i; j++) {
 311                                 if (s[j].command != BIOS_LINKER_LOADER_COMMAND_ALLOCATE)
 312                                         continue;
 313                                 if (strcmp(s[j].alloc.file, s[i].cksum.file) == 0)
 314                                         dst = j;
 315                         }
 316                         if (dst == -1)
 317                                 goto err;
 318
 319                         ptr = (uint8_t *)(addrs[dst] + s[i].cksum.offset);
 320                         cksum_data = (void *)(addrs[dst] + s[i].cksum.start);
 321                         cksum = acpi_checksum(cksum_data, s[i].cksum.length);
 322                         write_le8(ptr, cksum);
 323                         break;
 324
 325                 default:
 326                         printk(BIOS_DEBUG, "QEMU: acpi: unknown script cmd 0x%x @ %p\n",
 327                                s[i].command, s+i);
 328                         goto err;
 329                 };
 330         }
 331
 332         printk(BIOS_DEBUG, "QEMU: loaded ACPI tables from fw_cfg.\n");
 333         free(s);
 334         free(addrs);
 335         return ALIGN_UP(current, 16);
 336
 337 err:
 338         printk(BIOS_DEBUG, "QEMU: loading ACPI tables from fw_cfg failed.\n");
 339         free(s);
 340         free(addrs);
 341         return 0;
 342 }
 343
 344 /* ---------------------------------------------------------------------- */
 345 /* pick up smbios information from fw_cfg                                 */
 346
 347 #if CONFIG(GENERATE_SMBIOS_TABLES)
 348 static const char *type1_manufacturer;
 349 static const char *type1_product_name;
 350 static const char *type1_version;
 351 static const char *type1_serial_number;
 352 static const char *type1_family;
 353 static u8 type1_uuid[16];
 354
 355 static void fw_cfg_smbios_init(void)
 356 {
 357         static int done = 0;
 358         uint16_t i, count = 0;
 359         FwCfgSmbios entry;
 360         char *buf;
 361
 362         if (done)
 363                 return;
 364         done = 1;
 365
 366         fw_cfg_get(FW_CFG_SMBIOS_ENTRIES, &count, sizeof(count));
 367         for (i = 0; i < count; i++) {
 368                 fw_cfg_read(&entry, sizeof(entry));
 369                 buf = malloc(entry.length - sizeof(entry));
 370                 fw_cfg_read(buf, entry.length - sizeof(entry));
 371                 if (entry.headertype == SMBIOS_FIELD_ENTRY &&
 372                     entry.tabletype == 1) {
 373                         switch (entry.fieldoffset) {
 374                         case offsetof(struct smbios_type1, manufacturer):
 375                                 type1_manufacturer = strdup(buf);
 376                                 break;
 377                         case offsetof(struct smbios_type1, product_name):
 378                                 type1_product_name = strdup(buf);
 379                                 break;
 380                         case offsetof(struct smbios_type1, version):
 381                                 type1_version = strdup(buf);
 382                                 break;
 383                         case offsetof(struct smbios_type1, serial_number):
 384                                 type1_serial_number = strdup(buf);
 385                                 break;
 386                         case offsetof(struct smbios_type1, family):
 387                                 type1_family = strdup(buf);
 388                                 break;
 389                         case offsetof(struct smbios_type1, uuid):
 390                                 memcpy(type1_uuid, buf, 16);
 391                                 break;
 392                         }
 393                 }
 394                 free(buf);
 395         }
 396 }
 397
 398 static unsigned long smbios_next(unsigned long current)
 399 {
 400         struct smbios_header *header;
 401         int l, count = 0;
 402         char *s;
 403
 404         header = (void *)current;
 405         current += header->length;
 406         for (;;) {
 407                 s = (void *)current;
 408                 l = strlen(s);
 409                 if (!l)
 410                         return current + (count ? 1 : 2);
 411                 current += l + 1;
 412                 count++;
 413         }
 414 }
 415
 416 /*
 417  * Starting with version 2.1 qemu provides a full set of smbios tables
 418  * for the virtual hardware emulated, except type 0 (bios information).
 419  *
 420  * What we are going to do here is find the type0 table, keep it, and
 421  * override everything else generated by coreboot with the qemu smbios
 422  * tables.
 423  *
 424  * It's a bit hackish, but qemu is a special case (compared to real
 425  * hardware) and this way we don't need special qemu support in the
 426  * generic smbios code.
 427  */
 428 unsigned long fw_cfg_smbios_tables(int *handle, unsigned long *current)
 429 {
 430         FWCfgFile f;
 431         struct smbios_header *header;
 432         unsigned long start, end;
 433         int ret, i, count = 1;
 434         char *str;
 435
 436         if (fw_cfg_check_file(&f, "etc/smbios/smbios-tables"))
 437                 return 0;
 438
 439         printk(BIOS_DEBUG, "QEMU: found smbios tables in fw_cfg (len %d).\n", f.size);
 440
 441         /*
 442          * Search backwards for "coreboot" (first string in type0 table,
 443          * see src/arch/x86/boot/smbios.c), then find type0 table.
 444          */
 445         for (i = 0; i < 16384; i++) {
 446                 str = (char*)(*current - i);
 447                 if (strcmp(str, "coreboot") == 0)
 448                         break;
 449         }
 450         if (i == 16384)
 451                 return 0;
 452         i += sizeof(struct smbios_type0) - 2;
 453         header = (struct smbios_header *)(*current - i);
 454         if (header->type != SMBIOS_BIOS_INFORMATION || header->handle != 0)
 455                 return 0;
 456         printk(BIOS_DEBUG, "QEMU: coreboot type0 table found at 0x%lx.\n",
 457                *current - i);
 458         start = smbios_next(*current - i);
 459
 460         /*
 461          * Fetch smbios tables from qemu, go find the end marker.
 462          * We'll exclude the end marker as coreboot will add one.
 463          */
 464         printk(BIOS_DEBUG, "QEMU: loading smbios tables to 0x%lx\n", start);
 465         fw_cfg_get(f.select, (void *)start, f.size);
 466         end = start;
 467         do {
 468                 header = (struct smbios_header *)end;
 469                 if (header->type == SMBIOS_END_OF_TABLE)
 470                         break;
 471                 end = smbios_next(end);
 472                 count++;
 473         } while (end < start + f.size);
 474
 475         /* final fixups. */
 476         ret = end - *current;
 477         *current = end;
 478         *handle = count;
 479         return ret;
 480 }
 481
 482 const char *smbios_mainboard_manufacturer(void)
 483 {
 484         fw_cfg_smbios_init();
 485         return type1_manufacturer ?: CONFIG_MAINBOARD_SMBIOS_MANUFACTURER;
 486 }
 487
 488 const char *smbios_mainboard_product_name(void)
 489 {
 490         fw_cfg_smbios_init();
 491         return type1_product_name ?: CONFIG_MAINBOARD_SMBIOS_PRODUCT_NAME;
 492 }
 493
 494 const char *smbios_mainboard_version(void)
 495 {
 496         fw_cfg_smbios_init();
 497         return type1_version ?: CONFIG_MAINBOARD_VERSION;
 498 }
 499
 500 const char *smbios_mainboard_serial_number(void)
 501 {
 502         fw_cfg_smbios_init();
 503         return type1_serial_number ?: CONFIG_MAINBOARD_SERIAL_NUMBER;
 504 }
 505
 506 void smbios_system_set_uuid(u8 *uuid)
 507 {
 508         fw_cfg_smbios_init();
 509         memcpy(uuid, type1_uuid, 16);
 510 }
 511 #endif /* CONFIG(GENERATE_SMBIOS_TABLES) */
 512
 513 /*
 514  * Configure DMA setup
 515  */
 516
 517 static void fw_cfg_dma(int control, void *buf, int len)
 518 {
 519         volatile FwCfgDmaAccess dma;
 520         uintptr_t dma_desc_addr;
 521         uint32_t dma_desc_addr_hi, dma_desc_addr_lo;
 522
 523         dma.control = be32_to_cpu(control);
 524         dma.length  = be32_to_cpu(len);
 525         dma.address = be64_to_cpu((uintptr_t)buf);
 526
 527         dma_desc_addr = (uintptr_t)&dma;
 528         dma_desc_addr_lo = (uint32_t)(dma_desc_addr & 0xFFFFFFFFU);
 529         dma_desc_addr_hi = sizeof(uintptr_t) > sizeof(uint32_t)
 530                                 ? (uint32_t)(dma_desc_addr >> 32) : 0;
 531
 532         // Skip writing high half if unnecessary.
 533         if (dma_desc_addr_hi)
 534                 outl(be32_to_cpu(dma_desc_addr_hi), FW_CFG_DMA_ADDR_HIGH);
 535         outl(be32_to_cpu(dma_desc_addr_lo), FW_CFG_DMA_ADDR_LOW);
 536
 537         while (be32_to_cpu(dma.control) & ~FW_CFG_DMA_CTL_ERROR)
 538                 ;
 539 }