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/hw.h"
  12 #include "hw/arm/arm.h"
  13 #include "sysemu/sysemu.h"
  14 #include "hw/boards.h"
  15 #include "hw/loader.h"
  16 #include "elf.h"
  17 #include "sysemu/device_tree.h"
  18 #include "qemu/config-file.h"
  19
  20 #define KERNEL_ARGS_ADDR 0x100
  21 #define KERNEL_LOAD_ADDR 0x00010000
  22
  23 /* The worlds second smallest bootloader.  Set r0-r2, then jump to kernel.  */
  24 static uint32_t bootloader[] = {
  25   0xe3a00000, /* mov     r0, #0 */
  26   0xe59f1004, /* ldr     r1, [pc, #4] */
  27   0xe59f2004, /* ldr     r2, [pc, #4] */
  28   0xe59ff004, /* ldr     pc, [pc, #4] */
  29   0, /* Board ID */
  30   0, /* Address of kernel args.  Set by integratorcp_init.  */
  31   0  /* Kernel entry point.  Set by integratorcp_init.  */
  32 };
  33
  34 /* Handling for secondary CPU boot in a multicore system.
  35  * Unlike the uniprocessor/primary CPU boot, this is platform
  36  * dependent. The default code here is based on the secondary
  37  * CPU boot protocol used on realview/vexpress boards, with
  38  * some parameterisation to increase its flexibility.
  39  * QEMU platform models for which this code is not appropriate
  40  * should override write_secondary_boot and secondary_cpu_reset_hook
  41  * instead.
  42  *
  43  * This code enables the interrupt controllers for the secondary
  44  * CPUs and then puts all the secondary CPUs into a loop waiting
  45  * for an interprocessor interrupt and polling a configurable
  46  * location for the kernel secondary CPU entry point.
  47  */
  48 #define DSB_INSN 0xf57ff04f
  49 #define CP15_DSB_INSN 0xee070f9a /* mcr cp15, 0, r0, c7, c10, 4 */
  50
  51 static uint32_t smpboot[] = {
  52   0xe59f2028, /* ldr r2, gic_cpu_if */
  53   0xe59f0028, /* ldr r0, startaddr */
  54   0xe3a01001, /* mov r1, #1 */
  55   0xe5821000, /* str r1, [r2] - set GICC_CTLR.Enable */
  56   0xe3a010ff, /* mov r1, #0xff */
  57   0xe5821004, /* str r1, [r2, 4] - set GIC_PMR.Priority to 0xff */
  58   DSB_INSN,   /* dsb */
  59   0xe320f003, /* wfi */
  60   0xe5901000, /* ldr     r1, [r0] */
  61   0xe1110001, /* tst     r1, r1 */
  62   0x0afffffb, /* beq     <wfi> */
  63   0xe12fff11, /* bx      r1 */
  64   0,          /* gic_cpu_if: base address of GIC CPU interface */
  65   0           /* bootreg: Boot register address is held here */
  66 };
  67
  68 static void default_write_secondary(ARMCPU *cpu,
  69                                     const struct arm_boot_info *info)
  70 {
  71     int n;
  72     smpboot[ARRAY_SIZE(smpboot) - 1] = info->smp_bootreg_addr;
  73     smpboot[ARRAY_SIZE(smpboot) - 2] = info->gic_cpu_if_addr;
  74     for (n = 0; n < ARRAY_SIZE(smpboot); n++) {
  75         /* Replace DSB with the pre-v7 DSB if necessary. */
  76         if (!arm_feature(&cpu->env, ARM_FEATURE_V7) &&
  77             smpboot[n] == DSB_INSN) {
  78             smpboot[n] = CP15_DSB_INSN;
  79         }
  80         smpboot[n] = tswap32(smpboot[n]);
  81     }
  82     rom_add_blob_fixed("smpboot", smpboot, sizeof(smpboot),
  83                        info->smp_loader_start);
  84 }
  85
  86 static void default_reset_secondary(ARMCPU *cpu,
  87                                     const struct arm_boot_info *info)
  88 {
  89     CPUARMState *env = &cpu->env;
  90
  91     stl_phys_notdirty(info->smp_bootreg_addr, 0);
  92     env->regs[15] = info->smp_loader_start;
  93 }
  94
  95 #define WRITE_WORD(p, value) do { \
  96     stl_phys_notdirty(p, value);  \
  97     p += 4;                       \
  98 } while (0)
  99
 100 static void set_kernel_args(const struct arm_boot_info *info)
 101 {
 102     int initrd_size = info->initrd_size;
 103     hwaddr base = info->loader_start;
 104     hwaddr p;
 105
 106     p = base + KERNEL_ARGS_ADDR;
 107     /* ATAG_CORE */
 108     WRITE_WORD(p, 5);
 109     WRITE_WORD(p, 0x54410001);
 110     WRITE_WORD(p, 1);
 111     WRITE_WORD(p, 0x1000);
 112     WRITE_WORD(p, 0);
 113     /* ATAG_MEM */
 114     /* TODO: handle multiple chips on one ATAG list */
 115     WRITE_WORD(p, 4);
 116     WRITE_WORD(p, 0x54410002);
 117     WRITE_WORD(p, info->ram_size);
 118     WRITE_WORD(p, info->loader_start);
 119     if (initrd_size) {
 120         /* ATAG_INITRD2 */
 121         WRITE_WORD(p, 4);
 122         WRITE_WORD(p, 0x54420005);
 123         WRITE_WORD(p, info->initrd_start);
 124         WRITE_WORD(p, initrd_size);
 125     }
 126     if (info->kernel_cmdline && *info->kernel_cmdline) {
 127         /* ATAG_CMDLINE */
 128         int cmdline_size;
 129
 130         cmdline_size = strlen(info->kernel_cmdline);
 131         cpu_physical_memory_write(p + 8, info->kernel_cmdline,
 132                                   cmdline_size + 1);
 133         cmdline_size = (cmdline_size >> 2) + 1;
 134         WRITE_WORD(p, cmdline_size + 2);
 135         WRITE_WORD(p, 0x54410009);
 136         p += cmdline_size * 4;
 137     }
 138     if (info->atag_board) {
 139         /* ATAG_BOARD */
 140         int atag_board_len;
 141         uint8_t atag_board_buf[0x1000];
 142
 143         atag_board_len = (info->atag_board(info, atag_board_buf) + 3) & ~3;
 144         WRITE_WORD(p, (atag_board_len + 8) >> 2);
 145         WRITE_WORD(p, 0x414f4d50);
 146         cpu_physical_memory_write(p, atag_board_buf, atag_board_len);
 147         p += atag_board_len;
 148     }
 149     /* ATAG_END */
 150     WRITE_WORD(p, 0);
 151     WRITE_WORD(p, 0);
 152 }
 153
 154 static void set_kernel_args_old(const struct arm_boot_info *info)
 155 {
 156     hwaddr p;
 157     const char *s;
 158     int initrd_size = info->initrd_size;
 159     hwaddr base = info->loader_start;
 160
 161     /* see linux/include/asm-arm/setup.h */
 162     p = base + KERNEL_ARGS_ADDR;
 163     /* page_size */
 164     WRITE_WORD(p, 4096);
 165     /* nr_pages */
 166     WRITE_WORD(p, info->ram_size / 4096);
 167     /* ramdisk_size */
 168     WRITE_WORD(p, 0);
 169 #define FLAG_READONLY   1
 170 #define FLAG_RDLOAD     4
 171 #define FLAG_RDPROMPT   8
 172     /* flags */
 173     WRITE_WORD(p, FLAG_READONLY | FLAG_RDLOAD | FLAG_RDPROMPT);
 174     /* rootdev */
 175     WRITE_WORD(p, (31 << 8) | 0);       /* /dev/mtdblock0 */
 176     /* video_num_cols */
 177     WRITE_WORD(p, 0);
 178     /* video_num_rows */
 179     WRITE_WORD(p, 0);
 180     /* video_x */
 181     WRITE_WORD(p, 0);
 182     /* video_y */
 183     WRITE_WORD(p, 0);
 184     /* memc_control_reg */
 185     WRITE_WORD(p, 0);
 186     /* unsigned char sounddefault */
 187     /* unsigned char adfsdrives */
 188     /* unsigned char bytes_per_char_h */
 189     /* unsigned char bytes_per_char_v */
 190     WRITE_WORD(p, 0);
 191     /* pages_in_bank[4] */
 192     WRITE_WORD(p, 0);
 193     WRITE_WORD(p, 0);
 194     WRITE_WORD(p, 0);
 195     WRITE_WORD(p, 0);
 196     /* pages_in_vram */
 197     WRITE_WORD(p, 0);
 198     /* initrd_start */
 199     if (initrd_size) {
 200         WRITE_WORD(p, info->initrd_start);
 201     } else {
 202         WRITE_WORD(p, 0);
 203     }
 204     /* initrd_size */
 205     WRITE_WORD(p, initrd_size);
 206     /* rd_start */
 207     WRITE_WORD(p, 0);
 208     /* system_rev */
 209     WRITE_WORD(p, 0);
 210     /* system_serial_low */
 211     WRITE_WORD(p, 0);
 212     /* system_serial_high */
 213     WRITE_WORD(p, 0);
 214     /* mem_fclk_21285 */
 215     WRITE_WORD(p, 0);
 216     /* zero unused fields */
 217     while (p < base + KERNEL_ARGS_ADDR + 256 + 1024) {
 218         WRITE_WORD(p, 0);
 219     }
 220     s = info->kernel_cmdline;
 221     if (s) {
 222         cpu_physical_memory_write(p, s, strlen(s) + 1);
 223     } else {
 224         WRITE_WORD(p, 0);
 225     }
 226 }
 227
 228 static int load_dtb(hwaddr addr, const struct arm_boot_info *binfo)
 229 {
 230     uint32_t *mem_reg_property;
 231     uint32_t mem_reg_propsize;
 232     void *fdt = NULL;
 233     char *filename;
 234     int size, rc;
 235     uint32_t acells, scells, hival;
 236
 237     filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, binfo->dtb_filename);
 238     if (!filename) {
 239         fprintf(stderr, "Couldn't open dtb file %s\n", binfo->dtb_filename);
 240         goto fail;
 241     }
 242
 243     fdt = load_device_tree(filename, &size);
 244     if (!fdt) {
 245         fprintf(stderr, "Couldn't open dtb file %s\n", filename);
 246         g_free(filename);
 247         goto fail;
 248     }
 249     g_free(filename);
 250
 251     acells = qemu_devtree_getprop_cell(fdt, "/", "#address-cells");
 252     scells = qemu_devtree_getprop_cell(fdt, "/", "#size-cells");
 253     if (acells == 0 || scells == 0) {
 254         fprintf(stderr, "dtb file invalid (#address-cells or #size-cells 0)\n");
 255         goto fail;
 256     }
 257
 258     mem_reg_propsize = acells + scells;
 259     mem_reg_property = g_new0(uint32_t, mem_reg_propsize);
 260     mem_reg_property[acells - 1] = cpu_to_be32(binfo->loader_start);
 261     hival = cpu_to_be32(binfo->loader_start >> 32);
 262     if (acells > 1) {
 263         mem_reg_property[acells - 2] = hival;
 264     } else if (hival != 0) {
 265         fprintf(stderr, "qemu: dtb file not compatible with "
 266                 "RAM start address > 4GB\n");
 267         goto fail;
 268     }
 269     mem_reg_property[acells + scells - 1] = cpu_to_be32(binfo->ram_size);
 270     hival = cpu_to_be32(binfo->ram_size >> 32);
 271     if (scells > 1) {
 272         mem_reg_property[acells + scells - 2] = hival;
 273     } else if (hival != 0) {
 274         fprintf(stderr, "qemu: dtb file not compatible with "
 275                 "RAM size > 4GB\n");
 276         goto fail;
 277     }
 278
 279     rc = qemu_devtree_setprop(fdt, "/memory", "reg", mem_reg_property,
 280                               mem_reg_propsize * sizeof(uint32_t));
 281     if (rc < 0) {
 282         fprintf(stderr, "couldn't set /memory/reg\n");
 283         goto fail;
 284     }
 285
 286     if (binfo->kernel_cmdline && *binfo->kernel_cmdline) {
 287         rc = qemu_devtree_setprop_string(fdt, "/chosen", "bootargs",
 288                                           binfo->kernel_cmdline);
 289         if (rc < 0) {
 290             fprintf(stderr, "couldn't set /chosen/bootargs\n");
 291             goto fail;
 292         }
 293     }
 294
 295     if (binfo->initrd_size) {
 296         rc = qemu_devtree_setprop_cell(fdt, "/chosen", "linux,initrd-start",
 297                 binfo->initrd_start);
 298         if (rc < 0) {
 299             fprintf(stderr, "couldn't set /chosen/linux,initrd-start\n");
 300             goto fail;
 301         }
 302
 303         rc = qemu_devtree_setprop_cell(fdt, "/chosen", "linux,initrd-end",
 304                     binfo->initrd_start + binfo->initrd_size);
 305         if (rc < 0) {
 306             fprintf(stderr, "couldn't set /chosen/linux,initrd-end\n");
 307             goto fail;
 308         }
 309     }
 310     qemu_devtree_dumpdtb(fdt, size);
 311
 312     cpu_physical_memory_write(addr, fdt, size);
 313
 314     g_free(fdt);
 315
 316     return 0;
 317
 318 fail:
 319     g_free(fdt);
 320     return -1;
 321 }
 322
 323 static void do_cpu_reset(void *opaque)
 324 {
 325     ARMCPU *cpu = opaque;
 326     CPUARMState *env = &cpu->env;
 327     const struct arm_boot_info *info = env->boot_info;
 328
 329     cpu_reset(CPU(cpu));
 330     if (info) {
 331         if (!info->is_linux) {
 332             /* Jump to the entry point.  */
 333             env->regs[15] = info->entry & 0xfffffffe;
 334             env->thumb = info->entry & 1;
 335         } else {
 336             if (env == first_cpu) {
 337                 env->regs[15] = info->loader_start;
 338                 if (!info->dtb_filename) {
 339                     if (old_param) {
 340                         set_kernel_args_old(info);
 341                     } else {
 342                         set_kernel_args(info);
 343                     }
 344                 }
 345             } else {
 346                 info->secondary_cpu_reset_hook(cpu, info);
 347             }
 348         }
 349     }
 350 }
 351
 352 void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info)
 353 {
 354     CPUARMState *env = &cpu->env;
 355     int kernel_size;
 356     int initrd_size;
 357     int n;
 358     int is_linux = 0;
 359     uint64_t elf_entry;
 360     hwaddr entry;
 361     int big_endian;
 362     QemuOpts *machine_opts;
 363
 364     /* Load the kernel.  */
 365     if (!info->kernel_filename) {
 366         fprintf(stderr, "Kernel image must be specified\n");
 367         exit(1);
 368     }
 369
 370     machine_opts = qemu_opts_find(qemu_find_opts("machine"), 0);
 371     if (machine_opts) {
 372         info->dtb_filename = qemu_opt_get(machine_opts, "dtb");
 373     } else {
 374         info->dtb_filename = NULL;
 375     }
 376
 377     if (!info->secondary_cpu_reset_hook) {
 378         info->secondary_cpu_reset_hook = default_reset_secondary;
 379     }
 380     if (!info->write_secondary_boot) {
 381         info->write_secondary_boot = default_write_secondary;
 382     }
 383
 384     if (info->nb_cpus == 0)
 385         info->nb_cpus = 1;
 386
 387 #ifdef TARGET_WORDS_BIGENDIAN
 388     big_endian = 1;
 389 #else
 390     big_endian = 0;
 391 #endif
 392
 393     /* We want to put the initrd far enough into RAM that when the
 394      * kernel is uncompressed it will not clobber the initrd. However
 395      * on boards without much RAM we must ensure that we still leave
 396      * enough room for a decent sized initrd, and on boards with large
 397      * amounts of RAM we must avoid the initrd being so far up in RAM
 398      * that it is outside lowmem and inaccessible to the kernel.
 399      * So for boards with less  than 256MB of RAM we put the initrd
 400      * halfway into RAM, and for boards with 256MB of RAM or more we put
 401      * the initrd at 128MB.
 402      */
 403     info->initrd_start = info->loader_start +
 404         MIN(info->ram_size / 2, 128 * 1024 * 1024);
 405
 406     /* Assume that raw images are linux kernels, and ELF images are not.  */
 407     kernel_size = load_elf(info->kernel_filename, NULL, NULL, &elf_entry,
 408                            NULL, NULL, big_endian, ELF_MACHINE, 1);
 409     entry = elf_entry;
 410     if (kernel_size < 0) {
 411         kernel_size = load_uimage(info->kernel_filename, &entry, NULL,
 412                                   &is_linux);
 413     }
 414     if (kernel_size < 0) {
 415         entry = info->loader_start + KERNEL_LOAD_ADDR;
 416         kernel_size = load_image_targphys(info->kernel_filename, entry,
 417                                           info->ram_size - KERNEL_LOAD_ADDR);
 418         is_linux = 1;
 419     }
 420     if (kernel_size < 0) {
 421         fprintf(stderr, "qemu: could not load kernel '%s'\n",
 422                 info->kernel_filename);
 423         exit(1);
 424     }
 425     info->entry = entry;
 426     if (is_linux) {
 427         if (info->initrd_filename) {
 428             initrd_size = load_image_targphys(info->initrd_filename,
 429                                               info->initrd_start,
 430                                               info->ram_size -
 431                                               info->initrd_start);
 432             if (initrd_size < 0) {
 433                 fprintf(stderr, "qemu: could not load initrd '%s'\n",
 434                         info->initrd_filename);
 435                 exit(1);
 436             }
 437         } else {
 438             initrd_size = 0;
 439         }
 440         info->initrd_size = initrd_size;
 441
 442         bootloader[4] = info->board_id;
 443
 444         /* for device tree boot, we pass the DTB directly in r2. Otherwise
 445          * we point to the kernel args.
 446          */
 447         if (info->dtb_filename) {
 448             /* Place the DTB after the initrd in memory. Note that some
 449              * kernels will trash anything in the 4K page the initrd
 450              * ends in, so make sure the DTB isn't caught up in that.
 451              */
 452             hwaddr dtb_start = QEMU_ALIGN_UP(info->initrd_start + initrd_size,
 453                                              4096);
 454             if (load_dtb(dtb_start, info)) {
 455                 exit(1);
 456             }
 457             bootloader[5] = dtb_start;
 458         } else {
 459             bootloader[5] = info->loader_start + KERNEL_ARGS_ADDR;
 460             if (info->ram_size >= (1ULL << 32)) {
 461                 fprintf(stderr, "qemu: RAM size must be less than 4GB to boot"
 462                         " Linux kernel using ATAGS (try passing a device tree"
 463                         " using -dtb)\n");
 464                 exit(1);
 465             }
 466         }
 467         bootloader[6] = entry;
 468         for (n = 0; n < sizeof(bootloader) / 4; n++) {
 469             bootloader[n] = tswap32(bootloader[n]);
 470         }
 471         rom_add_blob_fixed("bootloader", bootloader, sizeof(bootloader),
 472                            info->loader_start);
 473         if (info->nb_cpus > 1) {
 474             info->write_secondary_boot(cpu, info);
 475         }
 476     }
 477     info->is_linux = is_linux;
 478
 479     for (; env; env = env->next_cpu) {
 480         cpu = arm_env_get_cpu(env);
 481         env->boot_info = info;
 482         qemu_register_reset(do_cpu_reset, cpu);
 483     }
 484 }