xref: /openbmc/qemu/hw/arm/boot.c (revision fcf5ef2a)
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 "qemu/osdep.h"
11 #include "qapi/error.h"
12 #include <libfdt.h>
13 #include "hw/hw.h"
14 #include "hw/arm/arm.h"
15 #include "hw/arm/linux-boot-if.h"
16 #include "sysemu/kvm.h"
17 #include "sysemu/sysemu.h"
18 #include "sysemu/numa.h"
19 #include "hw/boards.h"
20 #include "hw/loader.h"
21 #include "elf.h"
22 #include "sysemu/device_tree.h"
23 #include "qemu/config-file.h"
24 #include "exec/address-spaces.h"
25 
26 /* Kernel boot protocol is specified in the kernel docs
27  * Documentation/arm/Booting and Documentation/arm64/booting.txt
28  * They have different preferred image load offsets from system RAM base.
29  */
30 #define KERNEL_ARGS_ADDR 0x100
31 #define KERNEL_LOAD_ADDR 0x00010000
32 #define KERNEL64_LOAD_ADDR 0x00080000
33 
34 typedef enum {
35     FIXUP_NONE = 0,     /* do nothing */
36     FIXUP_TERMINATOR,   /* end of insns */
37     FIXUP_BOARDID,      /* overwrite with board ID number */
38     FIXUP_BOARD_SETUP,  /* overwrite with board specific setup code address */
39     FIXUP_ARGPTR,       /* overwrite with pointer to kernel args */
40     FIXUP_ENTRYPOINT,   /* overwrite with kernel entry point */
41     FIXUP_GIC_CPU_IF,   /* overwrite with GIC CPU interface address */
42     FIXUP_BOOTREG,      /* overwrite with boot register address */
43     FIXUP_DSB,          /* overwrite with correct DSB insn for cpu */
44     FIXUP_MAX,
45 } FixupType;
46 
47 typedef struct ARMInsnFixup {
48     uint32_t insn;
49     FixupType fixup;
50 } ARMInsnFixup;
51 
52 static const ARMInsnFixup bootloader_aarch64[] = {
53     { 0x580000c0 }, /* ldr x0, arg ; Load the lower 32-bits of DTB */
54     { 0xaa1f03e1 }, /* mov x1, xzr */
55     { 0xaa1f03e2 }, /* mov x2, xzr */
56     { 0xaa1f03e3 }, /* mov x3, xzr */
57     { 0x58000084 }, /* ldr x4, entry ; Load the lower 32-bits of kernel entry */
58     { 0xd61f0080 }, /* br x4      ; Jump to the kernel entry point */
59     { 0, FIXUP_ARGPTR }, /* arg: .word @DTB Lower 32-bits */
60     { 0 }, /* .word @DTB Higher 32-bits */
61     { 0, FIXUP_ENTRYPOINT }, /* entry: .word @Kernel Entry Lower 32-bits */
62     { 0 }, /* .word @Kernel Entry Higher 32-bits */
63     { 0, FIXUP_TERMINATOR }
64 };
65 
66 /* A very small bootloader: call the board-setup code (if needed),
67  * set r0-r2, then jump to the kernel.
68  * If we're not calling boot setup code then we don't copy across
69  * the first BOOTLOADER_NO_BOARD_SETUP_OFFSET insns in this array.
70  */
71 
72 static const ARMInsnFixup bootloader[] = {
73     { 0xe28fe004 }, /* add     lr, pc, #4 */
74     { 0xe51ff004 }, /* ldr     pc, [pc, #-4] */
75     { 0, FIXUP_BOARD_SETUP },
76 #define BOOTLOADER_NO_BOARD_SETUP_OFFSET 3
77     { 0xe3a00000 }, /* mov     r0, #0 */
78     { 0xe59f1004 }, /* ldr     r1, [pc, #4] */
79     { 0xe59f2004 }, /* ldr     r2, [pc, #4] */
80     { 0xe59ff004 }, /* ldr     pc, [pc, #4] */
81     { 0, FIXUP_BOARDID },
82     { 0, FIXUP_ARGPTR },
83     { 0, FIXUP_ENTRYPOINT },
84     { 0, FIXUP_TERMINATOR }
85 };
86 
87 /* Handling for secondary CPU boot in a multicore system.
88  * Unlike the uniprocessor/primary CPU boot, this is platform
89  * dependent. The default code here is based on the secondary
90  * CPU boot protocol used on realview/vexpress boards, with
91  * some parameterisation to increase its flexibility.
92  * QEMU platform models for which this code is not appropriate
93  * should override write_secondary_boot and secondary_cpu_reset_hook
94  * instead.
95  *
96  * This code enables the interrupt controllers for the secondary
97  * CPUs and then puts all the secondary CPUs into a loop waiting
98  * for an interprocessor interrupt and polling a configurable
99  * location for the kernel secondary CPU entry point.
100  */
101 #define DSB_INSN 0xf57ff04f
102 #define CP15_DSB_INSN 0xee070f9a /* mcr cp15, 0, r0, c7, c10, 4 */
103 
104 static const ARMInsnFixup smpboot[] = {
105     { 0xe59f2028 }, /* ldr r2, gic_cpu_if */
106     { 0xe59f0028 }, /* ldr r0, bootreg_addr */
107     { 0xe3a01001 }, /* mov r1, #1 */
108     { 0xe5821000 }, /* str r1, [r2] - set GICC_CTLR.Enable */
109     { 0xe3a010ff }, /* mov r1, #0xff */
110     { 0xe5821004 }, /* str r1, [r2, 4] - set GIC_PMR.Priority to 0xff */
111     { 0, FIXUP_DSB },   /* dsb */
112     { 0xe320f003 }, /* wfi */
113     { 0xe5901000 }, /* ldr     r1, [r0] */
114     { 0xe1110001 }, /* tst     r1, r1 */
115     { 0x0afffffb }, /* beq     <wfi> */
116     { 0xe12fff11 }, /* bx      r1 */
117     { 0, FIXUP_GIC_CPU_IF }, /* gic_cpu_if: .word 0x.... */
118     { 0, FIXUP_BOOTREG }, /* bootreg_addr: .word 0x.... */
119     { 0, FIXUP_TERMINATOR }
120 };
121 
122 static void write_bootloader(const char *name, hwaddr addr,
123                              const ARMInsnFixup *insns, uint32_t *fixupcontext)
124 {
125     /* Fix up the specified bootloader fragment and write it into
126      * guest memory using rom_add_blob_fixed(). fixupcontext is
127      * an array giving the values to write in for the fixup types
128      * which write a value into the code array.
129      */
130     int i, len;
131     uint32_t *code;
132 
133     len = 0;
134     while (insns[len].fixup != FIXUP_TERMINATOR) {
135         len++;
136     }
137 
138     code = g_new0(uint32_t, len);
139 
140     for (i = 0; i < len; i++) {
141         uint32_t insn = insns[i].insn;
142         FixupType fixup = insns[i].fixup;
143 
144         switch (fixup) {
145         case FIXUP_NONE:
146             break;
147         case FIXUP_BOARDID:
148         case FIXUP_BOARD_SETUP:
149         case FIXUP_ARGPTR:
150         case FIXUP_ENTRYPOINT:
151         case FIXUP_GIC_CPU_IF:
152         case FIXUP_BOOTREG:
153         case FIXUP_DSB:
154             insn = fixupcontext[fixup];
155             break;
156         default:
157             abort();
158         }
159         code[i] = tswap32(insn);
160     }
161 
162     rom_add_blob_fixed(name, code, len * sizeof(uint32_t), addr);
163 
164     g_free(code);
165 }
166 
167 static void default_write_secondary(ARMCPU *cpu,
168                                     const struct arm_boot_info *info)
169 {
170     uint32_t fixupcontext[FIXUP_MAX];
171 
172     fixupcontext[FIXUP_GIC_CPU_IF] = info->gic_cpu_if_addr;
173     fixupcontext[FIXUP_BOOTREG] = info->smp_bootreg_addr;
174     if (arm_feature(&cpu->env, ARM_FEATURE_V7)) {
175         fixupcontext[FIXUP_DSB] = DSB_INSN;
176     } else {
177         fixupcontext[FIXUP_DSB] = CP15_DSB_INSN;
178     }
179 
180     write_bootloader("smpboot", info->smp_loader_start,
181                      smpboot, fixupcontext);
182 }
183 
184 void arm_write_secure_board_setup_dummy_smc(ARMCPU *cpu,
185                                             const struct arm_boot_info *info,
186                                             hwaddr mvbar_addr)
187 {
188     int n;
189     uint32_t mvbar_blob[] = {
190         /* mvbar_addr: secure monitor vectors
191          * Default unimplemented and unused vectors to spin. Makes it
192          * easier to debug (as opposed to the CPU running away).
193          */
194         0xeafffffe, /* (spin) */
195         0xeafffffe, /* (spin) */
196         0xe1b0f00e, /* movs pc, lr ;SMC exception return */
197         0xeafffffe, /* (spin) */
198         0xeafffffe, /* (spin) */
199         0xeafffffe, /* (spin) */
200         0xeafffffe, /* (spin) */
201         0xeafffffe, /* (spin) */
202     };
203     uint32_t board_setup_blob[] = {
204         /* board setup addr */
205         0xe3a00e00 + (mvbar_addr >> 4), /* mov r0, #mvbar_addr */
206         0xee0c0f30, /* mcr     p15, 0, r0, c12, c0, 1 ;set MVBAR */
207         0xee110f11, /* mrc     p15, 0, r0, c1 , c1, 0 ;read SCR */
208         0xe3800031, /* orr     r0, #0x31              ;enable AW, FW, NS */
209         0xee010f11, /* mcr     p15, 0, r0, c1, c1, 0  ;write SCR */
210         0xe1a0100e, /* mov     r1, lr                 ;save LR across SMC */
211         0xe1600070, /* smc     #0                     ;call monitor to flush SCR */
212         0xe1a0f001, /* mov     pc, r1                 ;return */
213     };
214 
215     /* check that mvbar_addr is correctly aligned and relocatable (using MOV) */
216     assert((mvbar_addr & 0x1f) == 0 && (mvbar_addr >> 4) < 0x100);
217 
218     /* check that these blobs don't overlap */
219     assert((mvbar_addr + sizeof(mvbar_blob) <= info->board_setup_addr)
220           || (info->board_setup_addr + sizeof(board_setup_blob) <= mvbar_addr));
221 
222     for (n = 0; n < ARRAY_SIZE(mvbar_blob); n++) {
223         mvbar_blob[n] = tswap32(mvbar_blob[n]);
224     }
225     rom_add_blob_fixed("board-setup-mvbar", mvbar_blob, sizeof(mvbar_blob),
226                        mvbar_addr);
227 
228     for (n = 0; n < ARRAY_SIZE(board_setup_blob); n++) {
229         board_setup_blob[n] = tswap32(board_setup_blob[n]);
230     }
231     rom_add_blob_fixed("board-setup", board_setup_blob,
232                        sizeof(board_setup_blob), info->board_setup_addr);
233 }
234 
235 static void default_reset_secondary(ARMCPU *cpu,
236                                     const struct arm_boot_info *info)
237 {
238     CPUState *cs = CPU(cpu);
239 
240     address_space_stl_notdirty(&address_space_memory, info->smp_bootreg_addr,
241                                0, MEMTXATTRS_UNSPECIFIED, NULL);
242     cpu_set_pc(cs, info->smp_loader_start);
243 }
244 
245 static inline bool have_dtb(const struct arm_boot_info *info)
246 {
247     return info->dtb_filename || info->get_dtb;
248 }
249 
250 #define WRITE_WORD(p, value) do { \
251     address_space_stl_notdirty(&address_space_memory, p, value, \
252                                MEMTXATTRS_UNSPECIFIED, NULL);  \
253     p += 4;                       \
254 } while (0)
255 
256 static void set_kernel_args(const struct arm_boot_info *info)
257 {
258     int initrd_size = info->initrd_size;
259     hwaddr base = info->loader_start;
260     hwaddr p;
261 
262     p = base + KERNEL_ARGS_ADDR;
263     /* ATAG_CORE */
264     WRITE_WORD(p, 5);
265     WRITE_WORD(p, 0x54410001);
266     WRITE_WORD(p, 1);
267     WRITE_WORD(p, 0x1000);
268     WRITE_WORD(p, 0);
269     /* ATAG_MEM */
270     /* TODO: handle multiple chips on one ATAG list */
271     WRITE_WORD(p, 4);
272     WRITE_WORD(p, 0x54410002);
273     WRITE_WORD(p, info->ram_size);
274     WRITE_WORD(p, info->loader_start);
275     if (initrd_size) {
276         /* ATAG_INITRD2 */
277         WRITE_WORD(p, 4);
278         WRITE_WORD(p, 0x54420005);
279         WRITE_WORD(p, info->initrd_start);
280         WRITE_WORD(p, initrd_size);
281     }
282     if (info->kernel_cmdline && *info->kernel_cmdline) {
283         /* ATAG_CMDLINE */
284         int cmdline_size;
285 
286         cmdline_size = strlen(info->kernel_cmdline);
287         cpu_physical_memory_write(p + 8, info->kernel_cmdline,
288                                   cmdline_size + 1);
289         cmdline_size = (cmdline_size >> 2) + 1;
290         WRITE_WORD(p, cmdline_size + 2);
291         WRITE_WORD(p, 0x54410009);
292         p += cmdline_size * 4;
293     }
294     if (info->atag_board) {
295         /* ATAG_BOARD */
296         int atag_board_len;
297         uint8_t atag_board_buf[0x1000];
298 
299         atag_board_len = (info->atag_board(info, atag_board_buf) + 3) & ~3;
300         WRITE_WORD(p, (atag_board_len + 8) >> 2);
301         WRITE_WORD(p, 0x414f4d50);
302         cpu_physical_memory_write(p, atag_board_buf, atag_board_len);
303         p += atag_board_len;
304     }
305     /* ATAG_END */
306     WRITE_WORD(p, 0);
307     WRITE_WORD(p, 0);
308 }
309 
310 static void set_kernel_args_old(const struct arm_boot_info *info)
311 {
312     hwaddr p;
313     const char *s;
314     int initrd_size = info->initrd_size;
315     hwaddr base = info->loader_start;
316 
317     /* see linux/include/asm-arm/setup.h */
318     p = base + KERNEL_ARGS_ADDR;
319     /* page_size */
320     WRITE_WORD(p, 4096);
321     /* nr_pages */
322     WRITE_WORD(p, info->ram_size / 4096);
323     /* ramdisk_size */
324     WRITE_WORD(p, 0);
325 #define FLAG_READONLY	1
326 #define FLAG_RDLOAD	4
327 #define FLAG_RDPROMPT	8
328     /* flags */
329     WRITE_WORD(p, FLAG_READONLY | FLAG_RDLOAD | FLAG_RDPROMPT);
330     /* rootdev */
331     WRITE_WORD(p, (31 << 8) | 0);	/* /dev/mtdblock0 */
332     /* video_num_cols */
333     WRITE_WORD(p, 0);
334     /* video_num_rows */
335     WRITE_WORD(p, 0);
336     /* video_x */
337     WRITE_WORD(p, 0);
338     /* video_y */
339     WRITE_WORD(p, 0);
340     /* memc_control_reg */
341     WRITE_WORD(p, 0);
342     /* unsigned char sounddefault */
343     /* unsigned char adfsdrives */
344     /* unsigned char bytes_per_char_h */
345     /* unsigned char bytes_per_char_v */
346     WRITE_WORD(p, 0);
347     /* pages_in_bank[4] */
348     WRITE_WORD(p, 0);
349     WRITE_WORD(p, 0);
350     WRITE_WORD(p, 0);
351     WRITE_WORD(p, 0);
352     /* pages_in_vram */
353     WRITE_WORD(p, 0);
354     /* initrd_start */
355     if (initrd_size) {
356         WRITE_WORD(p, info->initrd_start);
357     } else {
358         WRITE_WORD(p, 0);
359     }
360     /* initrd_size */
361     WRITE_WORD(p, initrd_size);
362     /* rd_start */
363     WRITE_WORD(p, 0);
364     /* system_rev */
365     WRITE_WORD(p, 0);
366     /* system_serial_low */
367     WRITE_WORD(p, 0);
368     /* system_serial_high */
369     WRITE_WORD(p, 0);
370     /* mem_fclk_21285 */
371     WRITE_WORD(p, 0);
372     /* zero unused fields */
373     while (p < base + KERNEL_ARGS_ADDR + 256 + 1024) {
374         WRITE_WORD(p, 0);
375     }
376     s = info->kernel_cmdline;
377     if (s) {
378         cpu_physical_memory_write(p, s, strlen(s) + 1);
379     } else {
380         WRITE_WORD(p, 0);
381     }
382 }
383 
384 /**
385  * load_dtb() - load a device tree binary image into memory
386  * @addr:       the address to load the image at
387  * @binfo:      struct describing the boot environment
388  * @addr_limit: upper limit of the available memory area at @addr
389  *
390  * Load a device tree supplied by the machine or by the user  with the
391  * '-dtb' command line option, and put it at offset @addr in target
392  * memory.
393  *
394  * If @addr_limit contains a meaningful value (i.e., it is strictly greater
395  * than @addr), the device tree is only loaded if its size does not exceed
396  * the limit.
397  *
398  * Returns: the size of the device tree image on success,
399  *          0 if the image size exceeds the limit,
400  *          -1 on errors.
401  *
402  * Note: Must not be called unless have_dtb(binfo) is true.
403  */
404 static int load_dtb(hwaddr addr, const struct arm_boot_info *binfo,
405                     hwaddr addr_limit)
406 {
407     void *fdt = NULL;
408     int size, rc;
409     uint32_t acells, scells;
410     char *nodename;
411     unsigned int i;
412     hwaddr mem_base, mem_len;
413 
414     if (binfo->dtb_filename) {
415         char *filename;
416         filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, binfo->dtb_filename);
417         if (!filename) {
418             fprintf(stderr, "Couldn't open dtb file %s\n", binfo->dtb_filename);
419             goto fail;
420         }
421 
422         fdt = load_device_tree(filename, &size);
423         if (!fdt) {
424             fprintf(stderr, "Couldn't open dtb file %s\n", filename);
425             g_free(filename);
426             goto fail;
427         }
428         g_free(filename);
429     } else {
430         fdt = binfo->get_dtb(binfo, &size);
431         if (!fdt) {
432             fprintf(stderr, "Board was unable to create a dtb blob\n");
433             goto fail;
434         }
435     }
436 
437     if (addr_limit > addr && size > (addr_limit - addr)) {
438         /* Installing the device tree blob at addr would exceed addr_limit.
439          * Whether this constitutes failure is up to the caller to decide,
440          * so just return 0 as size, i.e., no error.
441          */
442         g_free(fdt);
443         return 0;
444     }
445 
446     acells = qemu_fdt_getprop_cell(fdt, "/", "#address-cells",
447                                    NULL, &error_fatal);
448     scells = qemu_fdt_getprop_cell(fdt, "/", "#size-cells",
449                                    NULL, &error_fatal);
450     if (acells == 0 || scells == 0) {
451         fprintf(stderr, "dtb file invalid (#address-cells or #size-cells 0)\n");
452         goto fail;
453     }
454 
455     if (scells < 2 && binfo->ram_size >= (1ULL << 32)) {
456         /* This is user error so deserves a friendlier error message
457          * than the failure of setprop_sized_cells would provide
458          */
459         fprintf(stderr, "qemu: dtb file not compatible with "
460                 "RAM size > 4GB\n");
461         goto fail;
462     }
463 
464     if (nb_numa_nodes > 0) {
465         /*
466          * Turn the /memory node created before into a NOP node, then create
467          * /memory@addr nodes for all numa nodes respectively.
468          */
469         qemu_fdt_nop_node(fdt, "/memory");
470         mem_base = binfo->loader_start;
471         for (i = 0; i < nb_numa_nodes; i++) {
472             mem_len = numa_info[i].node_mem;
473             nodename = g_strdup_printf("/memory@%" PRIx64, mem_base);
474             qemu_fdt_add_subnode(fdt, nodename);
475             qemu_fdt_setprop_string(fdt, nodename, "device_type", "memory");
476             rc = qemu_fdt_setprop_sized_cells(fdt, nodename, "reg",
477                                               acells, mem_base,
478                                               scells, mem_len);
479             if (rc < 0) {
480                 fprintf(stderr, "couldn't set %s/reg for node %d\n", nodename,
481                         i);
482                 goto fail;
483             }
484 
485             qemu_fdt_setprop_cell(fdt, nodename, "numa-node-id", i);
486             mem_base += mem_len;
487             g_free(nodename);
488         }
489     } else {
490         Error *err = NULL;
491 
492         rc = fdt_path_offset(fdt, "/memory");
493         if (rc < 0) {
494             qemu_fdt_add_subnode(fdt, "/memory");
495         }
496 
497         if (!qemu_fdt_getprop(fdt, "/memory", "device_type", NULL, &err)) {
498             qemu_fdt_setprop_string(fdt, "/memory", "device_type", "memory");
499         }
500 
501         rc = qemu_fdt_setprop_sized_cells(fdt, "/memory", "reg",
502                                           acells, binfo->loader_start,
503                                           scells, binfo->ram_size);
504         if (rc < 0) {
505             fprintf(stderr, "couldn't set /memory/reg\n");
506             goto fail;
507         }
508     }
509 
510     rc = fdt_path_offset(fdt, "/chosen");
511     if (rc < 0) {
512         qemu_fdt_add_subnode(fdt, "/chosen");
513     }
514 
515     if (binfo->kernel_cmdline && *binfo->kernel_cmdline) {
516         rc = qemu_fdt_setprop_string(fdt, "/chosen", "bootargs",
517                                      binfo->kernel_cmdline);
518         if (rc < 0) {
519             fprintf(stderr, "couldn't set /chosen/bootargs\n");
520             goto fail;
521         }
522     }
523 
524     if (binfo->initrd_size) {
525         rc = qemu_fdt_setprop_cell(fdt, "/chosen", "linux,initrd-start",
526                                    binfo->initrd_start);
527         if (rc < 0) {
528             fprintf(stderr, "couldn't set /chosen/linux,initrd-start\n");
529             goto fail;
530         }
531 
532         rc = qemu_fdt_setprop_cell(fdt, "/chosen", "linux,initrd-end",
533                                    binfo->initrd_start + binfo->initrd_size);
534         if (rc < 0) {
535             fprintf(stderr, "couldn't set /chosen/linux,initrd-end\n");
536             goto fail;
537         }
538     }
539 
540     if (binfo->modify_dtb) {
541         binfo->modify_dtb(binfo, fdt);
542     }
543 
544     qemu_fdt_dumpdtb(fdt, size);
545 
546     /* Put the DTB into the memory map as a ROM image: this will ensure
547      * the DTB is copied again upon reset, even if addr points into RAM.
548      */
549     rom_add_blob_fixed("dtb", fdt, size, addr);
550 
551     g_free(fdt);
552 
553     return size;
554 
555 fail:
556     g_free(fdt);
557     return -1;
558 }
559 
560 static void do_cpu_reset(void *opaque)
561 {
562     ARMCPU *cpu = opaque;
563     CPUState *cs = CPU(cpu);
564     CPUARMState *env = &cpu->env;
565     const struct arm_boot_info *info = env->boot_info;
566 
567     cpu_reset(cs);
568     if (info) {
569         if (!info->is_linux) {
570             int i;
571             /* Jump to the entry point.  */
572             uint64_t entry = info->entry;
573 
574             switch (info->endianness) {
575             case ARM_ENDIANNESS_LE:
576                 env->cp15.sctlr_el[1] &= ~SCTLR_E0E;
577                 for (i = 1; i < 4; ++i) {
578                     env->cp15.sctlr_el[i] &= ~SCTLR_EE;
579                 }
580                 env->uncached_cpsr &= ~CPSR_E;
581                 break;
582             case ARM_ENDIANNESS_BE8:
583                 env->cp15.sctlr_el[1] |= SCTLR_E0E;
584                 for (i = 1; i < 4; ++i) {
585                     env->cp15.sctlr_el[i] |= SCTLR_EE;
586                 }
587                 env->uncached_cpsr |= CPSR_E;
588                 break;
589             case ARM_ENDIANNESS_BE32:
590                 env->cp15.sctlr_el[1] |= SCTLR_B;
591                 break;
592             case ARM_ENDIANNESS_UNKNOWN:
593                 break; /* Board's decision */
594             default:
595                 g_assert_not_reached();
596             }
597 
598             if (!env->aarch64) {
599                 env->thumb = info->entry & 1;
600                 entry &= 0xfffffffe;
601             }
602             cpu_set_pc(cs, entry);
603         } else {
604             /* If we are booting Linux then we need to check whether we are
605              * booting into secure or non-secure state and adjust the state
606              * accordingly.  Out of reset, ARM is defined to be in secure state
607              * (SCR.NS = 0), we change that here if non-secure boot has been
608              * requested.
609              */
610             if (arm_feature(env, ARM_FEATURE_EL3)) {
611                 /* AArch64 is defined to come out of reset into EL3 if enabled.
612                  * If we are booting Linux then we need to adjust our EL as
613                  * Linux expects us to be in EL2 or EL1.  AArch32 resets into
614                  * SVC, which Linux expects, so no privilege/exception level to
615                  * adjust.
616                  */
617                 if (env->aarch64) {
618                     env->cp15.scr_el3 |= SCR_RW;
619                     if (arm_feature(env, ARM_FEATURE_EL2)) {
620                         env->cp15.hcr_el2 |= HCR_RW;
621                         env->pstate = PSTATE_MODE_EL2h;
622                     } else {
623                         env->pstate = PSTATE_MODE_EL1h;
624                     }
625                 }
626 
627                 /* Set to non-secure if not a secure boot */
628                 if (!info->secure_boot &&
629                     (cs != first_cpu || !info->secure_board_setup)) {
630                     /* Linux expects non-secure state */
631                     env->cp15.scr_el3 |= SCR_NS;
632                 }
633             }
634 
635             if (cs == first_cpu) {
636                 cpu_set_pc(cs, info->loader_start);
637 
638                 if (!have_dtb(info)) {
639                     if (old_param) {
640                         set_kernel_args_old(info);
641                     } else {
642                         set_kernel_args(info);
643                     }
644                 }
645             } else {
646                 info->secondary_cpu_reset_hook(cpu, info);
647             }
648         }
649     }
650 }
651 
652 /**
653  * load_image_to_fw_cfg() - Load an image file into an fw_cfg entry identified
654  *                          by key.
655  * @fw_cfg:         The firmware config instance to store the data in.
656  * @size_key:       The firmware config key to store the size of the loaded
657  *                  data under, with fw_cfg_add_i32().
658  * @data_key:       The firmware config key to store the loaded data under,
659  *                  with fw_cfg_add_bytes().
660  * @image_name:     The name of the image file to load. If it is NULL, the
661  *                  function returns without doing anything.
662  * @try_decompress: Whether the image should be decompressed (gunzipped) before
663  *                  adding it to fw_cfg. If decompression fails, the image is
664  *                  loaded as-is.
665  *
666  * In case of failure, the function prints an error message to stderr and the
667  * process exits with status 1.
668  */
669 static void load_image_to_fw_cfg(FWCfgState *fw_cfg, uint16_t size_key,
670                                  uint16_t data_key, const char *image_name,
671                                  bool try_decompress)
672 {
673     size_t size = -1;
674     uint8_t *data;
675 
676     if (image_name == NULL) {
677         return;
678     }
679 
680     if (try_decompress) {
681         size = load_image_gzipped_buffer(image_name,
682                                          LOAD_IMAGE_MAX_GUNZIP_BYTES, &data);
683     }
684 
685     if (size == (size_t)-1) {
686         gchar *contents;
687         gsize length;
688 
689         if (!g_file_get_contents(image_name, &contents, &length, NULL)) {
690             fprintf(stderr, "failed to load \"%s\"\n", image_name);
691             exit(1);
692         }
693         size = length;
694         data = (uint8_t *)contents;
695     }
696 
697     fw_cfg_add_i32(fw_cfg, size_key, size);
698     fw_cfg_add_bytes(fw_cfg, data_key, data, size);
699 }
700 
701 static int do_arm_linux_init(Object *obj, void *opaque)
702 {
703     if (object_dynamic_cast(obj, TYPE_ARM_LINUX_BOOT_IF)) {
704         ARMLinuxBootIf *albif = ARM_LINUX_BOOT_IF(obj);
705         ARMLinuxBootIfClass *albifc = ARM_LINUX_BOOT_IF_GET_CLASS(obj);
706         struct arm_boot_info *info = opaque;
707 
708         if (albifc->arm_linux_init) {
709             albifc->arm_linux_init(albif, info->secure_boot);
710         }
711     }
712     return 0;
713 }
714 
715 static uint64_t arm_load_elf(struct arm_boot_info *info, uint64_t *pentry,
716                              uint64_t *lowaddr, uint64_t *highaddr,
717                              int elf_machine)
718 {
719     bool elf_is64;
720     union {
721         Elf32_Ehdr h32;
722         Elf64_Ehdr h64;
723     } elf_header;
724     int data_swab = 0;
725     bool big_endian;
726     uint64_t ret = -1;
727     Error *err = NULL;
728 
729 
730     load_elf_hdr(info->kernel_filename, &elf_header, &elf_is64, &err);
731     if (err) {
732         return ret;
733     }
734 
735     if (elf_is64) {
736         big_endian = elf_header.h64.e_ident[EI_DATA] == ELFDATA2MSB;
737         info->endianness = big_endian ? ARM_ENDIANNESS_BE8
738                                       : ARM_ENDIANNESS_LE;
739     } else {
740         big_endian = elf_header.h32.e_ident[EI_DATA] == ELFDATA2MSB;
741         if (big_endian) {
742             if (bswap32(elf_header.h32.e_flags) & EF_ARM_BE8) {
743                 info->endianness = ARM_ENDIANNESS_BE8;
744             } else {
745                 info->endianness = ARM_ENDIANNESS_BE32;
746                 /* In BE32, the CPU has a different view of the per-byte
747                  * address map than the rest of the system. BE32 ELF files
748                  * are organised such that they can be programmed through
749                  * the CPU's per-word byte-reversed view of the world. QEMU
750                  * however loads ELF files independently of the CPU. So
751                  * tell the ELF loader to byte reverse the data for us.
752                  */
753                 data_swab = 2;
754             }
755         } else {
756             info->endianness = ARM_ENDIANNESS_LE;
757         }
758     }
759 
760     ret = load_elf(info->kernel_filename, NULL, NULL,
761                    pentry, lowaddr, highaddr, big_endian, elf_machine,
762                    1, data_swab);
763     if (ret <= 0) {
764         /* The header loaded but the image didn't */
765         exit(1);
766     }
767 
768     return ret;
769 }
770 
771 static void arm_load_kernel_notify(Notifier *notifier, void *data)
772 {
773     CPUState *cs;
774     int kernel_size;
775     int initrd_size;
776     int is_linux = 0;
777     uint64_t elf_entry, elf_low_addr, elf_high_addr;
778     int elf_machine;
779     hwaddr entry, kernel_load_offset;
780     static const ARMInsnFixup *primary_loader;
781     ArmLoadKernelNotifier *n = DO_UPCAST(ArmLoadKernelNotifier,
782                                          notifier, notifier);
783     ARMCPU *cpu = n->cpu;
784     struct arm_boot_info *info =
785         container_of(n, struct arm_boot_info, load_kernel_notifier);
786 
787     /* The board code is not supposed to set secure_board_setup unless
788      * running its code in secure mode is actually possible, and KVM
789      * doesn't support secure.
790      */
791     assert(!(info->secure_board_setup && kvm_enabled()));
792 
793     info->dtb_filename = qemu_opt_get(qemu_get_machine_opts(), "dtb");
794 
795     /* Load the kernel.  */
796     if (!info->kernel_filename || info->firmware_loaded) {
797 
798         if (have_dtb(info)) {
799             /* If we have a device tree blob, but no kernel to supply it to (or
800              * the kernel is supposed to be loaded by the bootloader), copy the
801              * DTB to the base of RAM for the bootloader to pick up.
802              */
803             if (load_dtb(info->loader_start, info, 0) < 0) {
804                 exit(1);
805             }
806         }
807 
808         if (info->kernel_filename) {
809             FWCfgState *fw_cfg;
810             bool try_decompressing_kernel;
811 
812             fw_cfg = fw_cfg_find();
813             try_decompressing_kernel = arm_feature(&cpu->env,
814                                                    ARM_FEATURE_AARCH64);
815 
816             /* Expose the kernel, the command line, and the initrd in fw_cfg.
817              * We don't process them here at all, it's all left to the
818              * firmware.
819              */
820             load_image_to_fw_cfg(fw_cfg,
821                                  FW_CFG_KERNEL_SIZE, FW_CFG_KERNEL_DATA,
822                                  info->kernel_filename,
823                                  try_decompressing_kernel);
824             load_image_to_fw_cfg(fw_cfg,
825                                  FW_CFG_INITRD_SIZE, FW_CFG_INITRD_DATA,
826                                  info->initrd_filename, false);
827 
828             if (info->kernel_cmdline) {
829                 fw_cfg_add_i32(fw_cfg, FW_CFG_CMDLINE_SIZE,
830                                strlen(info->kernel_cmdline) + 1);
831                 fw_cfg_add_string(fw_cfg, FW_CFG_CMDLINE_DATA,
832                                   info->kernel_cmdline);
833             }
834         }
835 
836         /* We will start from address 0 (typically a boot ROM image) in the
837          * same way as hardware.
838          */
839         return;
840     }
841 
842     if (arm_feature(&cpu->env, ARM_FEATURE_AARCH64)) {
843         primary_loader = bootloader_aarch64;
844         kernel_load_offset = KERNEL64_LOAD_ADDR;
845         elf_machine = EM_AARCH64;
846     } else {
847         primary_loader = bootloader;
848         if (!info->write_board_setup) {
849             primary_loader += BOOTLOADER_NO_BOARD_SETUP_OFFSET;
850         }
851         kernel_load_offset = KERNEL_LOAD_ADDR;
852         elf_machine = EM_ARM;
853     }
854 
855     if (!info->secondary_cpu_reset_hook) {
856         info->secondary_cpu_reset_hook = default_reset_secondary;
857     }
858     if (!info->write_secondary_boot) {
859         info->write_secondary_boot = default_write_secondary;
860     }
861 
862     if (info->nb_cpus == 0)
863         info->nb_cpus = 1;
864 
865     /* We want to put the initrd far enough into RAM that when the
866      * kernel is uncompressed it will not clobber the initrd. However
867      * on boards without much RAM we must ensure that we still leave
868      * enough room for a decent sized initrd, and on boards with large
869      * amounts of RAM we must avoid the initrd being so far up in RAM
870      * that it is outside lowmem and inaccessible to the kernel.
871      * So for boards with less  than 256MB of RAM we put the initrd
872      * halfway into RAM, and for boards with 256MB of RAM or more we put
873      * the initrd at 128MB.
874      */
875     info->initrd_start = info->loader_start +
876         MIN(info->ram_size / 2, 128 * 1024 * 1024);
877 
878     /* Assume that raw images are linux kernels, and ELF images are not.  */
879     kernel_size = arm_load_elf(info, &elf_entry, &elf_low_addr,
880                                &elf_high_addr, elf_machine);
881     if (kernel_size > 0 && have_dtb(info)) {
882         /* If there is still some room left at the base of RAM, try and put
883          * the DTB there like we do for images loaded with -bios or -pflash.
884          */
885         if (elf_low_addr > info->loader_start
886             || elf_high_addr < info->loader_start) {
887             /* Pass elf_low_addr as address limit to load_dtb if it may be
888              * pointing into RAM, otherwise pass '0' (no limit)
889              */
890             if (elf_low_addr < info->loader_start) {
891                 elf_low_addr = 0;
892             }
893             if (load_dtb(info->loader_start, info, elf_low_addr) < 0) {
894                 exit(1);
895             }
896         }
897     }
898     entry = elf_entry;
899     if (kernel_size < 0) {
900         kernel_size = load_uimage(info->kernel_filename, &entry, NULL,
901                                   &is_linux, NULL, NULL);
902     }
903     /* On aarch64, it's the bootloader's job to uncompress the kernel. */
904     if (arm_feature(&cpu->env, ARM_FEATURE_AARCH64) && kernel_size < 0) {
905         entry = info->loader_start + kernel_load_offset;
906         kernel_size = load_image_gzipped(info->kernel_filename, entry,
907                                          info->ram_size - kernel_load_offset);
908         is_linux = 1;
909     }
910     if (kernel_size < 0) {
911         entry = info->loader_start + kernel_load_offset;
912         kernel_size = load_image_targphys(info->kernel_filename, entry,
913                                           info->ram_size - kernel_load_offset);
914         is_linux = 1;
915     }
916     if (kernel_size < 0) {
917         fprintf(stderr, "qemu: could not load kernel '%s'\n",
918                 info->kernel_filename);
919         exit(1);
920     }
921     info->entry = entry;
922     if (is_linux) {
923         uint32_t fixupcontext[FIXUP_MAX];
924 
925         if (info->initrd_filename) {
926             initrd_size = load_ramdisk(info->initrd_filename,
927                                        info->initrd_start,
928                                        info->ram_size -
929                                        info->initrd_start);
930             if (initrd_size < 0) {
931                 initrd_size = load_image_targphys(info->initrd_filename,
932                                                   info->initrd_start,
933                                                   info->ram_size -
934                                                   info->initrd_start);
935             }
936             if (initrd_size < 0) {
937                 fprintf(stderr, "qemu: could not load initrd '%s'\n",
938                         info->initrd_filename);
939                 exit(1);
940             }
941         } else {
942             initrd_size = 0;
943         }
944         info->initrd_size = initrd_size;
945 
946         fixupcontext[FIXUP_BOARDID] = info->board_id;
947         fixupcontext[FIXUP_BOARD_SETUP] = info->board_setup_addr;
948 
949         /* for device tree boot, we pass the DTB directly in r2. Otherwise
950          * we point to the kernel args.
951          */
952         if (have_dtb(info)) {
953             hwaddr align;
954             hwaddr dtb_start;
955 
956             if (elf_machine == EM_AARCH64) {
957                 /*
958                  * Some AArch64 kernels on early bootup map the fdt region as
959                  *
960                  *   [ ALIGN_DOWN(fdt, 2MB) ... ALIGN_DOWN(fdt, 2MB) + 2MB ]
961                  *
962                  * Let's play safe and prealign it to 2MB to give us some space.
963                  */
964                 align = 2 * 1024 * 1024;
965             } else {
966                 /*
967                  * Some 32bit kernels will trash anything in the 4K page the
968                  * initrd ends in, so make sure the DTB isn't caught up in that.
969                  */
970                 align = 4096;
971             }
972 
973             /* Place the DTB after the initrd in memory with alignment. */
974             dtb_start = QEMU_ALIGN_UP(info->initrd_start + initrd_size, align);
975             if (load_dtb(dtb_start, info, 0) < 0) {
976                 exit(1);
977             }
978             fixupcontext[FIXUP_ARGPTR] = dtb_start;
979         } else {
980             fixupcontext[FIXUP_ARGPTR] = info->loader_start + KERNEL_ARGS_ADDR;
981             if (info->ram_size >= (1ULL << 32)) {
982                 fprintf(stderr, "qemu: RAM size must be less than 4GB to boot"
983                         " Linux kernel using ATAGS (try passing a device tree"
984                         " using -dtb)\n");
985                 exit(1);
986             }
987         }
988         fixupcontext[FIXUP_ENTRYPOINT] = entry;
989 
990         write_bootloader("bootloader", info->loader_start,
991                          primary_loader, fixupcontext);
992 
993         if (info->nb_cpus > 1) {
994             info->write_secondary_boot(cpu, info);
995         }
996         if (info->write_board_setup) {
997             info->write_board_setup(cpu, info);
998         }
999 
1000         /* Notify devices which need to fake up firmware initialization
1001          * that we're doing a direct kernel boot.
1002          */
1003         object_child_foreach_recursive(object_get_root(),
1004                                        do_arm_linux_init, info);
1005     }
1006     info->is_linux = is_linux;
1007 
1008     for (cs = CPU(cpu); cs; cs = CPU_NEXT(cs)) {
1009         ARM_CPU(cs)->env.boot_info = info;
1010     }
1011 }
1012 
1013 void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info)
1014 {
1015     CPUState *cs;
1016 
1017     info->load_kernel_notifier.cpu = cpu;
1018     info->load_kernel_notifier.notifier.notify = arm_load_kernel_notify;
1019     qemu_add_machine_init_done_notifier(&info->load_kernel_notifier.notifier);
1020 
1021     /* CPU objects (unlike devices) are not automatically reset on system
1022      * reset, so we must always register a handler to do so. If we're
1023      * actually loading a kernel, the handler is also responsible for
1024      * arranging that we start it correctly.
1025      */
1026     for (cs = CPU(cpu); cs; cs = CPU_NEXT(cs)) {
1027         qemu_register_reset(do_cpu_reset, ARM_CPU(cs));
1028     }
1029 }
1030 
1031 static const TypeInfo arm_linux_boot_if_info = {
1032     .name = TYPE_ARM_LINUX_BOOT_IF,
1033     .parent = TYPE_INTERFACE,
1034     .class_size = sizeof(ARMLinuxBootIfClass),
1035 };
1036 
1037 static void arm_linux_boot_register_types(void)
1038 {
1039     type_register_static(&arm_linux_boot_if_info);
1040 }
1041 
1042 type_init(arm_linux_boot_register_types)
1043