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     int size, rc;
 232     uint32_t acells, scells;
 233
 234     if (binfo->dtb_filename) {
 235         char *filename;
 236         filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, binfo->dtb_filename);
 237         if (!filename) {
 238             fprintf(stderr, "Couldn't open dtb file %s\n", binfo->dtb_filename);
 239             goto fail;
 240         }
 241
 242         fdt = load_device_tree(filename, &size);
 243         if (!fdt) {
 244             fprintf(stderr, "Couldn't open dtb file %s\n", filename);
 245             g_free(filename);
 246             goto fail;
 247         }
 248         g_free(filename);
 249     } else if (binfo->get_dtb) {
 250         fdt = binfo->get_dtb(binfo, &size);
 251         if (!fdt) {
 252             fprintf(stderr, "Board was unable to create a dtb blob\n");
 253             goto fail;
 254         }
 255     }
 256
 257     acells = qemu_devtree_getprop_cell(fdt, "/", "#address-cells");
 258     scells = qemu_devtree_getprop_cell(fdt, "/", "#size-cells");
 259     if (acells == 0 || scells == 0) {
 260         fprintf(stderr, "dtb file invalid (#address-cells or #size-cells 0)\n");
 261         goto fail;
 262     }
 263
 264     if (scells < 2 && binfo->ram_size >= (1ULL << 32)) {
 265         /* This is user error so deserves a friendlier error message
 266          * than the failure of setprop_sized_cells would provide
 267          */
 268         fprintf(stderr, "qemu: dtb file not compatible with "
 269                 "RAM size > 4GB\n");
 270         goto fail;
 271     }
 272
 273     rc = qemu_devtree_setprop_sized_cells(fdt, "/memory", "reg",
 274                                           acells, binfo->loader_start,
 275                                           scells, binfo->ram_size);
 276     if (rc < 0) {
 277         fprintf(stderr, "couldn't set /memory/reg\n");
 278         goto fail;
 279     }
 280
 281     if (binfo->kernel_cmdline && *binfo->kernel_cmdline) {
 282         rc = qemu_devtree_setprop_string(fdt, "/chosen", "bootargs",
 283                                           binfo->kernel_cmdline);
 284         if (rc < 0) {
 285             fprintf(stderr, "couldn't set /chosen/bootargs\n");
 286             goto fail;
 287         }
 288     }
 289
 290     if (binfo->initrd_size) {
 291         rc = qemu_devtree_setprop_cell(fdt, "/chosen", "linux,initrd-start",
 292                 binfo->initrd_start);
 293         if (rc < 0) {
 294             fprintf(stderr, "couldn't set /chosen/linux,initrd-start\n");
 295             goto fail;
 296         }
 297
 298         rc = qemu_devtree_setprop_cell(fdt, "/chosen", "linux,initrd-end",
 299                     binfo->initrd_start + binfo->initrd_size);
 300         if (rc < 0) {
 301             fprintf(stderr, "couldn't set /chosen/linux,initrd-end\n");
 302             goto fail;
 303         }
 304     }
 305
 306     if (binfo->modify_dtb) {
 307         binfo->modify_dtb(binfo, fdt);
 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 (CPU(cpu) == 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     CPUState *cs = CPU(cpu);
 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
 363     /* Load the kernel.  */
 364     if (!info->kernel_filename) {
 365         /* If no kernel specified, do nothing; we will start from address 0
 366          * (typically a boot ROM image) in the same way as hardware.
 367          */
 368         return;
 369     }
 370
 371     info->dtb_filename = qemu_opt_get(qemu_get_machine_opts(), "dtb");
 372
 373     if (!info->secondary_cpu_reset_hook) {
 374         info->secondary_cpu_reset_hook = default_reset_secondary;
 375     }
 376     if (!info->write_secondary_boot) {
 377         info->write_secondary_boot = default_write_secondary;
 378     }
 379
 380     if (info->nb_cpus == 0)
 381         info->nb_cpus = 1;
 382
 383 #ifdef TARGET_WORDS_BIGENDIAN
 384     big_endian = 1;
 385 #else
 386     big_endian = 0;
 387 #endif
 388
 389     /* We want to put the initrd far enough into RAM that when the
 390      * kernel is uncompressed it will not clobber the initrd. However
 391      * on boards without much RAM we must ensure that we still leave
 392      * enough room for a decent sized initrd, and on boards with large
 393      * amounts of RAM we must avoid the initrd being so far up in RAM
 394      * that it is outside lowmem and inaccessible to the kernel.
 395      * So for boards with less  than 256MB of RAM we put the initrd
 396      * halfway into RAM, and for boards with 256MB of RAM or more we put
 397      * the initrd at 128MB.
 398      */
 399     info->initrd_start = info->loader_start +
 400         MIN(info->ram_size / 2, 128 * 1024 * 1024);
 401
 402     /* Assume that raw images are linux kernels, and ELF images are not.  */
 403     kernel_size = load_elf(info->kernel_filename, NULL, NULL, &elf_entry,
 404                            NULL, NULL, big_endian, ELF_MACHINE, 1);
 405     entry = elf_entry;
 406     if (kernel_size < 0) {
 407         kernel_size = load_uimage(info->kernel_filename, &entry, NULL,
 408                                   &is_linux);
 409     }
 410     if (kernel_size < 0) {
 411         entry = info->loader_start + KERNEL_LOAD_ADDR;
 412         kernel_size = load_image_targphys(info->kernel_filename, entry,
 413                                           info->ram_size - KERNEL_LOAD_ADDR);
 414         is_linux = 1;
 415     }
 416     if (kernel_size < 0) {
 417         fprintf(stderr, "qemu: could not load kernel '%s'\n",
 418                 info->kernel_filename);
 419         exit(1);
 420     }
 421     info->entry = entry;
 422     if (is_linux) {
 423         if (info->initrd_filename) {
 424             initrd_size = load_ramdisk(info->initrd_filename,
 425                                        info->initrd_start,
 426                                        info->ram_size -
 427                                        info->initrd_start);
 428             if (initrd_size < 0) {
 429                 initrd_size = load_image_targphys(info->initrd_filename,
 430                                                   info->initrd_start,
 431                                                   info->ram_size -
 432                                                   info->initrd_start);
 433             }
 434             if (initrd_size < 0) {
 435                 fprintf(stderr, "qemu: could not load initrd '%s'\n",
 436                         info->initrd_filename);
 437                 exit(1);
 438             }
 439         } else {
 440             initrd_size = 0;
 441         }
 442         info->initrd_size = initrd_size;
 443
 444         bootloader[4] = info->board_id;
 445
 446         /* for device tree boot, we pass the DTB directly in r2. Otherwise
 447          * we point to the kernel args.
 448          */
 449         if (info->dtb_filename || info->get_dtb) {
 450             /* Place the DTB after the initrd in memory. Note that some
 451              * kernels will trash anything in the 4K page the initrd
 452              * ends in, so make sure the DTB isn't caught up in that.
 453              */
 454             hwaddr dtb_start = QEMU_ALIGN_UP(info->initrd_start + initrd_size,
 455                                              4096);
 456             if (load_dtb(dtb_start, info)) {
 457                 exit(1);
 458             }
 459             bootloader[5] = dtb_start;
 460         } else {
 461             bootloader[5] = info->loader_start + KERNEL_ARGS_ADDR;
 462             if (info->ram_size >= (1ULL << 32)) {
 463                 fprintf(stderr, "qemu: RAM size must be less than 4GB to boot"
 464                         " Linux kernel using ATAGS (try passing a device tree"
 465                         " using -dtb)\n");
 466                 exit(1);
 467             }
 468         }
 469         bootloader[6] = entry;
 470         for (n = 0; n < sizeof(bootloader) / 4; n++) {
 471             bootloader[n] = tswap32(bootloader[n]);
 472         }
 473         rom_add_blob_fixed("bootloader", bootloader, sizeof(bootloader),
 474                            info->loader_start);
 475         if (info->nb_cpus > 1) {
 476             info->write_secondary_boot(cpu, info);
 477         }
 478     }
 479     info->is_linux = is_linux;
 480
 481     for (; cs; cs = CPU_NEXT(cs)) {
 482         cpu = ARM_CPU(cs);
 483         cpu->env.boot_info = info;
 484         qemu_register_reset(do_cpu_reset, cpu);
 485     }
 486 }