hw/arm_boot.c

   1 /*
   2  * ARM kernel loader.
   3  *
   4  * Copyright (c) 2006-2007 CodeSourcery.
   5  * Written by Paul Brook
   6  *
   7  * This code is licensed under the GPL.
   8  */
   9
  10 #include "config.h"
  11 #include "hw.h"
  12 #include "arm-misc.h"
  13 #include "sysemu.h"
  14 #include "boards.h"
  15 #include "loader.h"
  16 #include "elf.h"
  17 #include "device_tree.h"
  18
  19 #define KERNEL_ARGS_ADDR 0x100
  20 #define KERNEL_LOAD_ADDR 0x00010000
  21
  22 /* The worlds second smallest bootloader.  Set r0-r2, then jump to kernel.  */
  23 static uint32_t bootloader[] = {
  24   0xe3a00000, /* mov     r0, #0 */
  25   0xe59f1004, /* ldr     r1, [pc, #4] */
  26   0xe59f2004, /* ldr     r2, [pc, #4] */
  27   0xe59ff004, /* ldr     pc, [pc, #4] */
  28   0, /* Board ID */
  29   0, /* Address of kernel args.  Set by integratorcp_init.  */
  30   0  /* Kernel entry point.  Set by integratorcp_init.  */
  31 };
  32
  33 /* Handling for secondary CPU boot in a multicore system.
  34  * Unlike the uniprocessor/primary CPU boot, this is platform
  35  * dependent. The default code here is based on the secondary
  36  * CPU boot protocol used on realview/vexpress boards, with
  37  * some parameterisation to increase its flexibility.
  38  * QEMU platform models for which this code is not appropriate
  39  * should override write_secondary_boot and secondary_cpu_reset_hook
  40  * instead.
  41  *
  42  * This code enables the interrupt controllers for the secondary
  43  * CPUs and then puts all the secondary CPUs into a loop waiting
  44  * for an interprocessor interrupt and polling a configurable
  45  * location for the kernel secondary CPU entry point.
  46  */
  47 static uint32_t smpboot[] = {
  48   0xe59f201c, /* ldr r2, gic_cpu_if */
  49   0xe59f001c, /* ldr r0, startaddr */
  50   0xe3a01001, /* mov r1, #1 */
  51   0xe5821000, /* str r1, [r2] */
  52   0xe320f003, /* wfi */
  53   0xe5901000, /* ldr     r1, [r0] */
  54   0xe1110001, /* tst     r1, r1 */
  55   0x0afffffb, /* beq     <wfi> */
  56   0xe12fff11, /* bx      r1 */
  57   0,          /* gic_cpu_if: base address of GIC CPU interface */
  58   0           /* bootreg: Boot register address is held here */
  59 };
  60
  61 static void default_write_secondary(ARMCPU *cpu,
  62                                     const struct arm_boot_info *info)
  63 {
  64     int n;
  65     smpboot[ARRAY_SIZE(smpboot) - 1] = info->smp_bootreg_addr;
  66     smpboot[ARRAY_SIZE(smpboot) - 2] = info->gic_cpu_if_addr;
  67     for (n = 0; n < ARRAY_SIZE(smpboot); n++) {
  68         smpboot[n] = tswap32(smpboot[n]);
  69     }
  70     rom_add_blob_fixed("smpboot", smpboot, sizeof(smpboot),
  71                        info->smp_loader_start);
  72 }
  73
  74 static void default_reset_secondary(ARMCPU *cpu,
  75                                     const struct arm_boot_info *info)
  76 {
  77     CPUARMState *env = &cpu->env;
  78
  79     stl_phys_notdirty(info->smp_bootreg_addr, 0);
  80     env->regs[15] = info->smp_loader_start;
  81 }
  82
  83 #define WRITE_WORD(p, value) do { \
  84     stl_phys_notdirty(p, value);  \
  85     p += 4;                       \
  86 } while (0)
  87
  88 static void set_kernel_args(const struct arm_boot_info *info)
  89 {
  90     int initrd_size = info->initrd_size;
  91     hwaddr base = info->loader_start;
  92     hwaddr p;
  93
  94     p = base + KERNEL_ARGS_ADDR;
  95     /* ATAG_CORE */
  96     WRITE_WORD(p, 5);
  97     WRITE_WORD(p, 0x54410001);
  98     WRITE_WORD(p, 1);
  99     WRITE_WORD(p, 0x1000);
 100     WRITE_WORD(p, 0);
 101     /* ATAG_MEM */
 102     /* TODO: handle multiple chips on one ATAG list */
 103     WRITE_WORD(p, 4);
 104     WRITE_WORD(p, 0x54410002);
 105     WRITE_WORD(p, info->ram_size);
 106     WRITE_WORD(p, info->loader_start);
 107     if (initrd_size) {
 108         /* ATAG_INITRD2 */
 109         WRITE_WORD(p, 4);
 110         WRITE_WORD(p, 0x54420005);
 111         WRITE_WORD(p, info->initrd_start);
 112         WRITE_WORD(p, initrd_size);
 113     }
 114     if (info->kernel_cmdline && *info->kernel_cmdline) {
 115         /* ATAG_CMDLINE */
 116         int cmdline_size;
 117
 118         cmdline_size = strlen(info->kernel_cmdline);
 119         cpu_physical_memory_write(p + 8, (void *)info->kernel_cmdline,
 120                                   cmdline_size + 1);
 121         cmdline_size = (cmdline_size >> 2) + 1;
 122         WRITE_WORD(p, cmdline_size + 2);
 123         WRITE_WORD(p, 0x54410009);
 124         p += cmdline_size * 4;
 125     }
 126     if (info->atag_board) {
 127         /* ATAG_BOARD */
 128         int atag_board_len;
 129         uint8_t atag_board_buf[0x1000];
 130
 131         atag_board_len = (info->atag_board(info, atag_board_buf) + 3) & ~3;
 132         WRITE_WORD(p, (atag_board_len + 8) >> 2);
 133         WRITE_WORD(p, 0x414f4d50);
 134         cpu_physical_memory_write(p, atag_board_buf, atag_board_len);
 135         p += atag_board_len;
 136     }
 137     /* ATAG_END */
 138     WRITE_WORD(p, 0);
 139     WRITE_WORD(p, 0);
 140 }
 141
 142 static void set_kernel_args_old(const struct arm_boot_info *info)
 143 {
 144     hwaddr p;
 145     const char *s;
 146     int initrd_size = info->initrd_size;
 147     hwaddr base = info->loader_start;
 148
 149     /* see linux/include/asm-arm/setup.h */
 150     p = base + KERNEL_ARGS_ADDR;
 151     /* page_size */
 152     WRITE_WORD(p, 4096);
 153     /* nr_pages */
 154     WRITE_WORD(p, info->ram_size / 4096);
 155     /* ramdisk_size */
 156     WRITE_WORD(p, 0);
 157 #define FLAG_READONLY   1
 158 #define FLAG_RDLOAD     4
 159 #define FLAG_RDPROMPT   8
 160     /* flags */
 161     WRITE_WORD(p, FLAG_READONLY | FLAG_RDLOAD | FLAG_RDPROMPT);
 162     /* rootdev */
 163     WRITE_WORD(p, (31 << 8) | 0);       /* /dev/mtdblock0 */
 164     /* video_num_cols */
 165     WRITE_WORD(p, 0);
 166     /* video_num_rows */
 167     WRITE_WORD(p, 0);
 168     /* video_x */
 169     WRITE_WORD(p, 0);
 170     /* video_y */
 171     WRITE_WORD(p, 0);
 172     /* memc_control_reg */
 173     WRITE_WORD(p, 0);
 174     /* unsigned char sounddefault */
 175     /* unsigned char adfsdrives */
 176     /* unsigned char bytes_per_char_h */
 177     /* unsigned char bytes_per_char_v */
 178     WRITE_WORD(p, 0);
 179     /* pages_in_bank[4] */
 180     WRITE_WORD(p, 0);
 181     WRITE_WORD(p, 0);
 182     WRITE_WORD(p, 0);
 183     WRITE_WORD(p, 0);
 184     /* pages_in_vram */
 185     WRITE_WORD(p, 0);
 186     /* initrd_start */
 187     if (initrd_size) {
 188         WRITE_WORD(p, info->initrd_start);
 189     } else {
 190         WRITE_WORD(p, 0);
 191     }
 192     /* initrd_size */
 193     WRITE_WORD(p, initrd_size);
 194     /* rd_start */
 195     WRITE_WORD(p, 0);
 196     /* system_rev */
 197     WRITE_WORD(p, 0);
 198     /* system_serial_low */
 199     WRITE_WORD(p, 0);
 200     /* system_serial_high */
 201     WRITE_WORD(p, 0);
 202     /* mem_fclk_21285 */
 203     WRITE_WORD(p, 0);
 204     /* zero unused fields */
 205     while (p < base + KERNEL_ARGS_ADDR + 256 + 1024) {
 206         WRITE_WORD(p, 0);
 207     }
 208     s = info->kernel_cmdline;
 209     if (s) {
 210         cpu_physical_memory_write(p, (void *)s, strlen(s) + 1);
 211     } else {
 212         WRITE_WORD(p, 0);
 213     }
 214 }
 215
 216 static int load_dtb(hwaddr addr, const struct arm_boot_info *binfo)
 217 {
 218 #ifdef CONFIG_FDT
 219     uint32_t *mem_reg_property;
 220     uint32_t mem_reg_propsize;
 221     void *fdt = NULL;
 222     char *filename;
 223     int size, rc;
 224     uint32_t acells, scells, hival;
 225
 226     filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, binfo->dtb_filename);
 227     if (!filename) {
 228         fprintf(stderr, "Couldn't open dtb file %s\n", binfo->dtb_filename);
 229         return -1;
 230     }
 231
 232     fdt = load_device_tree(filename, &size);
 233     if (!fdt) {
 234         fprintf(stderr, "Couldn't open dtb file %s\n", filename);
 235         g_free(filename);
 236         return -1;
 237     }
 238     g_free(filename);
 239
 240     acells = qemu_devtree_getprop_cell(fdt, "/", "#address-cells");
 241     scells = qemu_devtree_getprop_cell(fdt, "/", "#size-cells");
 242     if (acells == 0 || scells == 0) {
 243         fprintf(stderr, "dtb file invalid (#address-cells or #size-cells 0)\n");
 244         return -1;
 245     }
 246
 247     mem_reg_propsize = acells + scells;
 248     mem_reg_property = g_new0(uint32_t, mem_reg_propsize);
 249     mem_reg_property[acells - 1] = cpu_to_be32(binfo->loader_start);
 250     hival = cpu_to_be32(binfo->loader_start >> 32);
 251     if (acells > 1) {
 252         mem_reg_property[acells - 2] = hival;
 253     } else if (hival != 0) {
 254         fprintf(stderr, "qemu: dtb file not compatible with "
 255                 "RAM start address > 4GB\n");
 256         exit(1);
 257     }
 258     mem_reg_property[acells + scells - 1] = cpu_to_be32(binfo->ram_size);
 259     hival = cpu_to_be32(binfo->ram_size >> 32);
 260     if (scells > 1) {
 261         mem_reg_property[acells + scells - 2] = hival;
 262     } else if (hival != 0) {
 263         fprintf(stderr, "qemu: dtb file not compatible with "
 264                 "RAM size > 4GB\n");
 265         exit(1);
 266     }
 267
 268     rc = qemu_devtree_setprop(fdt, "/memory", "reg", mem_reg_property,
 269                               mem_reg_propsize * sizeof(uint32_t));
 270     if (rc < 0) {
 271         fprintf(stderr, "couldn't set /memory/reg\n");
 272     }
 273
 274     if (binfo->kernel_cmdline && *binfo->kernel_cmdline) {
 275         rc = qemu_devtree_setprop_string(fdt, "/chosen", "bootargs",
 276                                           binfo->kernel_cmdline);
 277         if (rc < 0) {
 278             fprintf(stderr, "couldn't set /chosen/bootargs\n");
 279         }
 280     }
 281
 282     if (binfo->initrd_size) {
 283         rc = qemu_devtree_setprop_cell(fdt, "/chosen", "linux,initrd-start",
 284                 binfo->initrd_start);
 285         if (rc < 0) {
 286             fprintf(stderr, "couldn't set /chosen/linux,initrd-start\n");
 287         }
 288
 289         rc = qemu_devtree_setprop_cell(fdt, "/chosen", "linux,initrd-end",
 290                     binfo->initrd_start + binfo->initrd_size);
 291         if (rc < 0) {
 292             fprintf(stderr, "couldn't set /chosen/linux,initrd-end\n");
 293         }
 294     }
 295
 296     cpu_physical_memory_write(addr, fdt, size);
 297
 298     return 0;
 299
 300 #else
 301     fprintf(stderr, "Device tree requested, "
 302                 "but qemu was compiled without fdt support\n");
 303     return -1;
 304 #endif
 305 }
 306
 307 static void do_cpu_reset(void *opaque)
 308 {
 309     ARMCPU *cpu = opaque;
 310     CPUARMState *env = &cpu->env;
 311     const struct arm_boot_info *info = env->boot_info;
 312
 313     cpu_reset(CPU(cpu));
 314     if (info) {
 315         if (!info->is_linux) {
 316             /* Jump to the entry point.  */
 317             env->regs[15] = info->entry & 0xfffffffe;
 318             env->thumb = info->entry & 1;
 319         } else {
 320             if (env == first_cpu) {
 321                 env->regs[15] = info->loader_start;
 322                 if (!info->dtb_filename) {
 323                     if (old_param) {
 324                         set_kernel_args_old(info);
 325                     } else {
 326                         set_kernel_args(info);
 327                     }
 328                 }
 329             } else {
 330                 info->secondary_cpu_reset_hook(cpu, info);
 331             }
 332         }
 333     }
 334 }
 335
 336 void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info)
 337 {
 338     CPUARMState *env = &cpu->env;
 339     int kernel_size;
 340     int initrd_size;
 341     int n;
 342     int is_linux = 0;
 343     uint64_t elf_entry;
 344     hwaddr entry;
 345     int big_endian;
 346     QemuOpts *machine_opts;
 347
 348     /* Load the kernel.  */
 349     if (!info->kernel_filename) {
 350         fprintf(stderr, "Kernel image must be specified\n");
 351         exit(1);
 352     }
 353
 354     machine_opts = qemu_opts_find(qemu_find_opts("machine"), 0);
 355     if (machine_opts) {
 356         info->dtb_filename = qemu_opt_get(machine_opts, "dtb");
 357     } else {
 358         info->dtb_filename = NULL;
 359     }
 360
 361     if (!info->secondary_cpu_reset_hook) {
 362         info->secondary_cpu_reset_hook = default_reset_secondary;
 363     }
 364     if (!info->write_secondary_boot) {
 365         info->write_secondary_boot = default_write_secondary;
 366     }
 367
 368     if (info->nb_cpus == 0)
 369         info->nb_cpus = 1;
 370
 371 #ifdef TARGET_WORDS_BIGENDIAN
 372     big_endian = 1;
 373 #else
 374     big_endian = 0;
 375 #endif
 376
 377     /* We want to put the initrd far enough into RAM that when the
 378      * kernel is uncompressed it will not clobber the initrd. However
 379      * on boards without much RAM we must ensure that we still leave
 380      * enough room for a decent sized initrd, and on boards with large
 381      * amounts of RAM we must avoid the initrd being so far up in RAM
 382      * that it is outside lowmem and inaccessible to the kernel.
 383      * So for boards with less  than 256MB of RAM we put the initrd
 384      * halfway into RAM, and for boards with 256MB of RAM or more we put
 385      * the initrd at 128MB.
 386      */
 387     info->initrd_start = info->loader_start +
 388         MIN(info->ram_size / 2, 128 * 1024 * 1024);
 389
 390     /* Assume that raw images are linux kernels, and ELF images are not.  */
 391     kernel_size = load_elf(info->kernel_filename, NULL, NULL, &elf_entry,
 392                            NULL, NULL, big_endian, ELF_MACHINE, 1);
 393     entry = elf_entry;
 394     if (kernel_size < 0) {
 395         kernel_size = load_uimage(info->kernel_filename, &entry, NULL,
 396                                   &is_linux);
 397     }
 398     if (kernel_size < 0) {
 399         entry = info->loader_start + KERNEL_LOAD_ADDR;
 400         kernel_size = load_image_targphys(info->kernel_filename, entry,
 401                                           info->ram_size - KERNEL_LOAD_ADDR);
 402         is_linux = 1;
 403     }
 404     if (kernel_size < 0) {
 405         fprintf(stderr, "qemu: could not load kernel '%s'\n",
 406                 info->kernel_filename);
 407         exit(1);
 408     }
 409     info->entry = entry;
 410     if (is_linux) {
 411         if (info->initrd_filename) {
 412             initrd_size = load_image_targphys(info->initrd_filename,
 413                                               info->initrd_start,
 414                                               info->ram_size -
 415                                               info->initrd_start);
 416             if (initrd_size < 0) {
 417                 fprintf(stderr, "qemu: could not load initrd '%s'\n",
 418                         info->initrd_filename);
 419                 exit(1);
 420             }
 421         } else {
 422             initrd_size = 0;
 423         }
 424         info->initrd_size = initrd_size;
 425
 426         bootloader[4] = info->board_id;
 427
 428         /* for device tree boot, we pass the DTB directly in r2. Otherwise
 429          * we point to the kernel args.
 430          */
 431         if (info->dtb_filename) {
 432             /* Place the DTB after the initrd in memory */
 433             hwaddr dtb_start = TARGET_PAGE_ALIGN(info->initrd_start +
 434                                                  initrd_size);
 435             if (load_dtb(dtb_start, info)) {
 436                 exit(1);
 437             }
 438             bootloader[5] = dtb_start;
 439         } else {
 440             bootloader[5] = info->loader_start + KERNEL_ARGS_ADDR;
 441             if (info->ram_size >= (1ULL << 32)) {
 442                 fprintf(stderr, "qemu: RAM size must be less than 4GB to boot"
 443                         " Linux kernel using ATAGS (try passing a device tree"
 444                         " using -dtb)\n");
 445                 exit(1);
 446             }
 447         }
 448         bootloader[6] = entry;
 449         for (n = 0; n < sizeof(bootloader) / 4; n++) {
 450             bootloader[n] = tswap32(bootloader[n]);
 451         }
 452         rom_add_blob_fixed("bootloader", bootloader, sizeof(bootloader),
 453                            info->loader_start);
 454         if (info->nb_cpus > 1) {
 455             info->write_secondary_boot(cpu, info);
 456         }
 457     }
 458     info->is_linux = is_linux;
 459
 460     for (; env; env = env->next_cpu) {
 461         cpu = arm_env_get_cpu(env);
 462         env->boot_info = info;
 463         qemu_register_reset(do_cpu_reset, cpu);
 464     }
 465 }