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     void *fdt = NULL;
 231     char *filename;
 232     int size, rc;
 233     uint32_t acells, scells;
 234
 235     filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, binfo->dtb_filename);
 236     if (!filename) {
 237         fprintf(stderr, "Couldn't open dtb file %s\n", binfo->dtb_filename);
 238         goto fail;
 239     }
 240
 241     fdt = load_device_tree(filename, &size);
 242     if (!fdt) {
 243         fprintf(stderr, "Couldn't open dtb file %s\n", filename);
 244         g_free(filename);
 245         goto fail;
 246     }
 247     g_free(filename);
 248
 249     acells = qemu_devtree_getprop_cell(fdt, "/", "#address-cells");
 250     scells = qemu_devtree_getprop_cell(fdt, "/", "#size-cells");
 251     if (acells == 0 || scells == 0) {
 252         fprintf(stderr, "dtb file invalid (#address-cells or #size-cells 0)\n");
 253         goto fail;
 254     }
 255
 256     if (scells < 2 && binfo->ram_size >= (1ULL << 32)) {
 257         /* This is user error so deserves a friendlier error message
 258          * than the failure of setprop_sized_cells would provide
 259          */
 260         fprintf(stderr, "qemu: dtb file not compatible with "
 261                 "RAM size > 4GB\n");
 262         goto fail;
 263     }
 264
 265     rc = qemu_devtree_setprop_sized_cells(fdt, "/memory", "reg",
 266                                           acells, binfo->loader_start,
 267                                           scells, binfo->ram_size);
 268     if (rc < 0) {
 269         fprintf(stderr, "couldn't set /memory/reg\n");
 270         goto fail;
 271     }
 272
 273     if (binfo->kernel_cmdline && *binfo->kernel_cmdline) {
 274         rc = qemu_devtree_setprop_string(fdt, "/chosen", "bootargs",
 275                                           binfo->kernel_cmdline);
 276         if (rc < 0) {
 277             fprintf(stderr, "couldn't set /chosen/bootargs\n");
 278             goto fail;
 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             goto fail;
 288         }
 289
 290         rc = qemu_devtree_setprop_cell(fdt, "/chosen", "linux,initrd-end",
 291                     binfo->initrd_start + binfo->initrd_size);
 292         if (rc < 0) {
 293             fprintf(stderr, "couldn't set /chosen/linux,initrd-end\n");
 294             goto fail;
 295         }
 296     }
 297
 298     if (binfo->modify_dtb) {
 299         binfo->modify_dtb(binfo, fdt);
 300     }
 301
 302     qemu_devtree_dumpdtb(fdt, size);
 303
 304     cpu_physical_memory_write(addr, fdt, size);
 305
 306     g_free(fdt);
 307
 308     return 0;
 309
 310 fail:
 311     g_free(fdt);
 312     return -1;
 313 }
 314
 315 static void do_cpu_reset(void *opaque)
 316 {
 317     ARMCPU *cpu = opaque;
 318     CPUARMState *env = &cpu->env;
 319     const struct arm_boot_info *info = env->boot_info;
 320
 321     cpu_reset(CPU(cpu));
 322     if (info) {
 323         if (!info->is_linux) {
 324             /* Jump to the entry point.  */
 325             env->regs[15] = info->entry & 0xfffffffe;
 326             env->thumb = info->entry & 1;
 327         } else {
 328             if (CPU(cpu) == first_cpu) {
 329                 env->regs[15] = info->loader_start;
 330                 if (!info->dtb_filename) {
 331                     if (old_param) {
 332                         set_kernel_args_old(info);
 333                     } else {
 334                         set_kernel_args(info);
 335                     }
 336                 }
 337             } else {
 338                 info->secondary_cpu_reset_hook(cpu, info);
 339             }
 340         }
 341     }
 342 }
 343
 344 void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info)
 345 {
 346     CPUState *cs = CPU(cpu);
 347     int kernel_size;
 348     int initrd_size;
 349     int n;
 350     int is_linux = 0;
 351     uint64_t elf_entry;
 352     hwaddr entry;
 353     int big_endian;
 354
 355     /* Load the kernel.  */
 356     if (!info->kernel_filename) {
 357         fprintf(stderr, "Kernel image must be specified\n");
 358         exit(1);
 359     }
 360
 361     info->dtb_filename = qemu_opt_get(qemu_get_machine_opts(), "dtb");
 362
 363     if (!info->secondary_cpu_reset_hook) {
 364         info->secondary_cpu_reset_hook = default_reset_secondary;
 365     }
 366     if (!info->write_secondary_boot) {
 367         info->write_secondary_boot = default_write_secondary;
 368     }
 369
 370     if (info->nb_cpus == 0)
 371         info->nb_cpus = 1;
 372
 373 #ifdef TARGET_WORDS_BIGENDIAN
 374     big_endian = 1;
 375 #else
 376     big_endian = 0;
 377 #endif
 378
 379     /* We want to put the initrd far enough into RAM that when the
 380      * kernel is uncompressed it will not clobber the initrd. However
 381      * on boards without much RAM we must ensure that we still leave
 382      * enough room for a decent sized initrd, and on boards with large
 383      * amounts of RAM we must avoid the initrd being so far up in RAM
 384      * that it is outside lowmem and inaccessible to the kernel.
 385      * So for boards with less  than 256MB of RAM we put the initrd
 386      * halfway into RAM, and for boards with 256MB of RAM or more we put
 387      * the initrd at 128MB.
 388      */
 389     info->initrd_start = info->loader_start +
 390         MIN(info->ram_size / 2, 128 * 1024 * 1024);
 391
 392     /* Assume that raw images are linux kernels, and ELF images are not.  */
 393     kernel_size = load_elf(info->kernel_filename, NULL, NULL, &elf_entry,
 394                            NULL, NULL, big_endian, ELF_MACHINE, 1);
 395     entry = elf_entry;
 396     if (kernel_size < 0) {
 397         kernel_size = load_uimage(info->kernel_filename, &entry, NULL,
 398                                   &is_linux);
 399     }
 400     if (kernel_size < 0) {
 401         entry = info->loader_start + KERNEL_LOAD_ADDR;
 402         kernel_size = load_image_targphys(info->kernel_filename, entry,
 403                                           info->ram_size - KERNEL_LOAD_ADDR);
 404         is_linux = 1;
 405     }
 406     if (kernel_size < 0) {
 407         fprintf(stderr, "qemu: could not load kernel '%s'\n",
 408                 info->kernel_filename);
 409         exit(1);
 410     }
 411     info->entry = entry;
 412     if (is_linux) {
 413         if (info->initrd_filename) {
 414             initrd_size = load_image_targphys(info->initrd_filename,
 415                                               info->initrd_start,
 416                                               info->ram_size -
 417                                               info->initrd_start);
 418             if (initrd_size < 0) {
 419                 fprintf(stderr, "qemu: could not load initrd '%s'\n",
 420                         info->initrd_filename);
 421                 exit(1);
 422             }
 423         } else {
 424             initrd_size = 0;
 425         }
 426         info->initrd_size = initrd_size;
 427
 428         bootloader[4] = info->board_id;
 429
 430         /* for device tree boot, we pass the DTB directly in r2. Otherwise
 431          * we point to the kernel args.
 432          */
 433         if (info->dtb_filename) {
 434             /* Place the DTB after the initrd in memory. Note that some
 435              * kernels will trash anything in the 4K page the initrd
 436              * ends in, so make sure the DTB isn't caught up in that.
 437              */
 438             hwaddr dtb_start = QEMU_ALIGN_UP(info->initrd_start + initrd_size,
 439                                              4096);
 440             if (load_dtb(dtb_start, info)) {
 441                 exit(1);
 442             }
 443             bootloader[5] = dtb_start;
 444         } else {
 445             bootloader[5] = info->loader_start + KERNEL_ARGS_ADDR;
 446             if (info->ram_size >= (1ULL << 32)) {
 447                 fprintf(stderr, "qemu: RAM size must be less than 4GB to boot"
 448                         " Linux kernel using ATAGS (try passing a device tree"
 449                         " using -dtb)\n");
 450                 exit(1);
 451             }
 452         }
 453         bootloader[6] = entry;
 454         for (n = 0; n < sizeof(bootloader) / 4; n++) {
 455             bootloader[n] = tswap32(bootloader[n]);
 456         }
 457         rom_add_blob_fixed("bootloader", bootloader, sizeof(bootloader),
 458                            info->loader_start);
 459         if (info->nb_cpus > 1) {
 460             info->write_secondary_boot(cpu, info);
 461         }
 462     }
 463     info->is_linux = is_linux;
 464
 465     for (; cs; cs = cs->next_cpu) {
 466         cpu = ARM_CPU(cs);
 467         cpu->env.boot_info = info;
 468         qemu_register_reset(do_cpu_reset, cpu);
 469     }
 470 }