hw/i386/pc_sysfw.c

   1 /*
   2  * QEMU PC System Firmware
   3  *
   4  * Copyright (c) 2003-2004 Fabrice Bellard
   5  * Copyright (c) 2011-2012 Intel Corporation
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a copy
   8  * of this software and associated documentation files (the "Software"), to deal
   9  * in the Software without restriction, including without limitation the rights
  10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11  * copies of the Software, and to permit persons to whom the Software is
  12  * furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included in
  15  * all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  23  * THE SOFTWARE.
  24  */
  25
  26 #include "qemu/osdep.h"
  27 #include "qemu-common.h"
  28 #include "qapi/error.h"
  29 #include "sysemu/block-backend.h"
  30 #include "qemu/error-report.h"
  31 #include "qemu/option.h"
  32 #include "qemu/units.h"
  33 #include "hw/sysbus.h"
  34 #include "hw/i386/x86.h"
  35 #include "hw/i386/pc.h"
  36 #include "hw/loader.h"
  37 #include "hw/qdev-properties.h"
  38 #include "sysemu/sysemu.h"
  39 #include "hw/block/flash.h"
  40 #include "sysemu/kvm.h"
  41 #include "sysemu/sev.h"
  42
  43 #define FLASH_SECTOR_SIZE 4096
  44
  45 static void pc_isa_bios_init(MemoryRegion *rom_memory,
  46                              MemoryRegion *flash_mem,
  47                              int ram_size)
  48 {
  49     int isa_bios_size;
  50     MemoryRegion *isa_bios;
  51     uint64_t flash_size;
  52     void *flash_ptr, *isa_bios_ptr;
  53
  54     flash_size = memory_region_size(flash_mem);
  55
  56     /* map the last 128KB of the BIOS in ISA space */
  57     isa_bios_size = MIN(flash_size, 128 * KiB);
  58     isa_bios = g_malloc(sizeof(*isa_bios));
  59     memory_region_init_ram(isa_bios, NULL, "isa-bios", isa_bios_size,
  60                            &error_fatal);
  61     memory_region_add_subregion_overlap(rom_memory,
  62                                         0x100000 - isa_bios_size,
  63                                         isa_bios,
  64                                         1);
  65
  66     /* copy ISA rom image from top of flash memory */
  67     flash_ptr = memory_region_get_ram_ptr(flash_mem);
  68     isa_bios_ptr = memory_region_get_ram_ptr(isa_bios);
  69     memcpy(isa_bios_ptr,
  70            ((uint8_t*)flash_ptr) + (flash_size - isa_bios_size),
  71            isa_bios_size);
  72
  73     memory_region_set_readonly(isa_bios, true);
  74 }
  75
  76 static PFlashCFI01 *pc_pflash_create(PCMachineState *pcms,
  77                                      const char *name,
  78                                      const char *alias_prop_name)
  79 {
  80     DeviceState *dev = qdev_new(TYPE_PFLASH_CFI01);
  81
  82     qdev_prop_set_uint64(dev, "sector-length", FLASH_SECTOR_SIZE);
  83     qdev_prop_set_uint8(dev, "width", 1);
  84     qdev_prop_set_string(dev, "name", name);
  85     object_property_add_child(OBJECT(pcms), name, OBJECT(dev));
  86     object_property_add_alias(OBJECT(pcms), alias_prop_name,
  87                               OBJECT(dev), "drive");
  88     /*
  89      * The returned reference is tied to the child property and
  90      * will be removed with object_unparent.
  91      */
  92     object_unref(OBJECT(dev));
  93     return PFLASH_CFI01(dev);
  94 }
  95
  96 void pc_system_flash_create(PCMachineState *pcms)
  97 {
  98     PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(pcms);
  99
 100     if (pcmc->pci_enabled) {
 101         pcms->flash[0] = pc_pflash_create(pcms, "system.flash0",
 102                                           "pflash0");
 103         pcms->flash[1] = pc_pflash_create(pcms, "system.flash1",
 104                                           "pflash1");
 105     }
 106 }
 107
 108 void pc_system_flash_cleanup_unused(PCMachineState *pcms)
 109 {
 110     char *prop_name;
 111     int i;
 112     Object *dev_obj;
 113
 114     assert(PC_MACHINE_GET_CLASS(pcms)->pci_enabled);
 115
 116     for (i = 0; i < ARRAY_SIZE(pcms->flash); i++) {
 117         dev_obj = OBJECT(pcms->flash[i]);
 118         if (!object_property_get_bool(dev_obj, "realized", &error_abort)) {
 119             prop_name = g_strdup_printf("pflash%d", i);
 120             object_property_del(OBJECT(pcms), prop_name);
 121             g_free(prop_name);
 122             object_unparent(dev_obj);
 123             pcms->flash[i] = NULL;
 124         }
 125     }
 126 }
 127
 128 #define OVMF_TABLE_FOOTER_GUID "96b582de-1fb2-45f7-baea-a366c55a082d"
 129
 130 static uint8_t *ovmf_table;
 131 static int ovmf_table_len;
 132
 133 static void pc_system_parse_ovmf_flash(uint8_t *flash_ptr, size_t flash_size)
 134 {
 135     uint8_t *ptr;
 136     QemuUUID guid;
 137     int tot_len;
 138
 139     /* should only be called once */
 140     if (ovmf_table) {
 141         return;
 142     }
 143
 144     if (flash_size < TARGET_PAGE_SIZE) {
 145         return;
 146     }
 147
 148     /*
 149      * if this is OVMF there will be a table footer
 150      * guid 48 bytes before the end of the flash file.  If it's
 151      * not found, silently abort the flash parsing.
 152      */
 153     qemu_uuid_parse(OVMF_TABLE_FOOTER_GUID, &guid);
 154     guid = qemu_uuid_bswap(guid); /* guids are LE */
 155     ptr = flash_ptr + flash_size - 48;
 156     if (!qemu_uuid_is_equal((QemuUUID *)ptr, &guid)) {
 157         return;
 158     }
 159
 160     /* if found, just before is two byte table length */
 161     ptr -= sizeof(uint16_t);
 162     tot_len = le16_to_cpu(*(uint16_t *)ptr) - sizeof(guid) - sizeof(uint16_t);
 163
 164     if (tot_len <= 0) {
 165         return;
 166     }
 167
 168     ovmf_table = g_malloc(tot_len);
 169     ovmf_table_len = tot_len;
 170
 171     /*
 172      * ptr is the foot of the table, so copy it all to the newly
 173      * allocated ovmf_table and then set the ovmf_table pointer
 174      * to the table foot
 175      */
 176     memcpy(ovmf_table, ptr - tot_len, tot_len);
 177     ovmf_table += tot_len;
 178 }
 179
 180 bool pc_system_ovmf_table_find(const char *entry, uint8_t **data,
 181                                int *data_len)
 182 {
 183     uint8_t *ptr = ovmf_table;
 184     int tot_len = ovmf_table_len;
 185     QemuUUID entry_guid;
 186
 187     if (qemu_uuid_parse(entry, &entry_guid) < 0) {
 188         return false;
 189     }
 190
 191     if (!ptr) {
 192         return false;
 193     }
 194
 195     entry_guid = qemu_uuid_bswap(entry_guid); /* guids are LE */
 196     while (tot_len >= sizeof(QemuUUID) + sizeof(uint16_t)) {
 197         int len;
 198         QemuUUID *guid;
 199
 200         /*
 201          * The data structure is
 202          *   arbitrary length data
 203          *   2 byte length of entire entry
 204          *   16 byte guid
 205          */
 206         guid = (QemuUUID *)(ptr - sizeof(QemuUUID));
 207         len = le16_to_cpu(*(uint16_t *)(ptr - sizeof(QemuUUID) -
 208                                         sizeof(uint16_t)));
 209
 210         /*
 211          * just in case the table is corrupt, wouldn't want to spin in
 212          * the zero case
 213          */
 214         if (len < sizeof(QemuUUID) + sizeof(uint16_t)) {
 215             return false;
 216         } else if (len > tot_len) {
 217             return false;
 218         }
 219
 220         ptr -= len;
 221         tot_len -= len;
 222         if (qemu_uuid_is_equal(guid, &entry_guid)) {
 223             if (data) {
 224                 *data = ptr;
 225             }
 226             if (data_len) {
 227                 *data_len = len - sizeof(QemuUUID) - sizeof(uint16_t);
 228             }
 229             return true;
 230         }
 231     }
 232     return false;
 233 }
 234
 235 /*
 236  * Map the pcms->flash[] from 4GiB downward, and realize.
 237  * Map them in descending order, i.e. pcms->flash[0] at the top,
 238  * without gaps.
 239  * Stop at the first pcms->flash[0] lacking a block backend.
 240  * Set each flash's size from its block backend.  Fatal error if the
 241  * size isn't a non-zero multiple of 4KiB, or the total size exceeds
 242  * pcms->max_fw_size.
 243  *
 244  * If pcms->flash[0] has a block backend, its memory is passed to
 245  * pc_isa_bios_init().  Merging several flash devices for isa-bios is
 246  * not supported.
 247  */
 248 static void pc_system_flash_map(PCMachineState *pcms,
 249                                 MemoryRegion *rom_memory)
 250 {
 251     hwaddr total_size = 0;
 252     int i;
 253     BlockBackend *blk;
 254     int64_t size;
 255     PFlashCFI01 *system_flash;
 256     MemoryRegion *flash_mem;
 257     void *flash_ptr;
 258     int flash_size;
 259     int ret;
 260
 261     assert(PC_MACHINE_GET_CLASS(pcms)->pci_enabled);
 262
 263     for (i = 0; i < ARRAY_SIZE(pcms->flash); i++) {
 264         system_flash = pcms->flash[i];
 265         blk = pflash_cfi01_get_blk(system_flash);
 266         if (!blk) {
 267             break;
 268         }
 269         size = blk_getlength(blk);
 270         if (size < 0) {
 271             error_report("can't get size of block device %s: %s",
 272                          blk_name(blk), strerror(-size));
 273             exit(1);
 274         }
 275         if (size == 0 || !QEMU_IS_ALIGNED(size, FLASH_SECTOR_SIZE)) {
 276             error_report("system firmware block device %s has invalid size "
 277                          "%" PRId64,
 278                          blk_name(blk), size);
 279             info_report("its size must be a non-zero multiple of 0x%x",
 280                         FLASH_SECTOR_SIZE);
 281             exit(1);
 282         }
 283         if ((hwaddr)size != size
 284             || total_size > HWADDR_MAX - size
 285             || total_size + size > pcms->max_fw_size) {
 286             error_report("combined size of system firmware exceeds "
 287                          "%" PRIu64 " bytes",
 288                          pcms->max_fw_size);
 289             exit(1);
 290         }
 291
 292         total_size += size;
 293         qdev_prop_set_uint32(DEVICE(system_flash), "num-blocks",
 294                              size / FLASH_SECTOR_SIZE);
 295         sysbus_realize_and_unref(SYS_BUS_DEVICE(system_flash), &error_fatal);
 296         sysbus_mmio_map(SYS_BUS_DEVICE(system_flash), 0,
 297                         0x100000000ULL - total_size);
 298
 299         if (i == 0) {
 300             flash_mem = pflash_cfi01_get_memory(system_flash);
 301             pc_isa_bios_init(rom_memory, flash_mem, size);
 302
 303             /* Encrypt the pflash boot ROM */
 304             if (sev_enabled()) {
 305                 flash_ptr = memory_region_get_ram_ptr(flash_mem);
 306                 flash_size = memory_region_size(flash_mem);
 307                 /*
 308                  * OVMF places a GUIDed structures in the flash, so
 309                  * search for them
 310                  */
 311                 pc_system_parse_ovmf_flash(flash_ptr, flash_size);
 312
 313                 ret = sev_es_save_reset_vector(flash_ptr, flash_size);
 314                 if (ret) {
 315                     error_report("failed to locate and/or save reset vector");
 316                     exit(1);
 317                 }
 318
 319                 sev_encrypt_flash(flash_ptr, flash_size, &error_fatal);
 320             }
 321         }
 322     }
 323 }
 324
 325 void pc_system_firmware_init(PCMachineState *pcms,
 326                              MemoryRegion *rom_memory)
 327 {
 328     PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(pcms);
 329     int i;
 330     BlockBackend *pflash_blk[ARRAY_SIZE(pcms->flash)];
 331
 332     if (!pcmc->pci_enabled) {
 333         x86_bios_rom_init(MACHINE(pcms), "bios.bin", rom_memory, true);
 334         return;
 335     }
 336
 337     /* Map legacy -drive if=pflash to machine properties */
 338     for (i = 0; i < ARRAY_SIZE(pcms->flash); i++) {
 339         pflash_cfi01_legacy_drive(pcms->flash[i],
 340                                   drive_get(IF_PFLASH, 0, i));
 341         pflash_blk[i] = pflash_cfi01_get_blk(pcms->flash[i]);
 342     }
 343
 344     /* Reject gaps */
 345     for (i = 1; i < ARRAY_SIZE(pcms->flash); i++) {
 346         if (pflash_blk[i] && !pflash_blk[i - 1]) {
 347             error_report("pflash%d requires pflash%d", i, i - 1);
 348             exit(1);
 349         }
 350     }
 351
 352     if (!pflash_blk[0]) {
 353         /* Machine property pflash0 not set, use ROM mode */
 354         x86_bios_rom_init(MACHINE(pcms), "bios.bin", rom_memory, false);
 355     } else {
 356         if (kvm_enabled() && !kvm_readonly_mem_enabled()) {
 357             /*
 358              * Older KVM cannot execute from device memory. So, flash
 359              * memory cannot be used unless the readonly memory kvm
 360              * capability is present.
 361              */
 362             error_report("pflash with kvm requires KVM readonly memory support");
 363             exit(1);
 364         }
 365
 366         pc_system_flash_map(pcms, rom_memory);
 367     }
 368
 369     pc_system_flash_cleanup_unused(pcms);
 370 }