fdt_machdep.c revision 1.49 1 /* $NetBSD: fdt_machdep.c,v 1.49 2018/10/30 21:32:35 jmcneill Exp $ */
2
3 /*-
4 * Copyright (c) 2015-2017 Jared McNeill <jmcneill (at) invisible.ca>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: fdt_machdep.c,v 1.49 2018/10/30 21:32:35 jmcneill Exp $");
31
32 #include "opt_machdep.h"
33 #include "opt_bootconfig.h"
34 #include "opt_ddb.h"
35 #include "opt_md.h"
36 #include "opt_arm_debug.h"
37 #include "opt_multiprocessor.h"
38 #include "opt_cpuoptions.h"
39 #include "opt_efi.h"
40
41 #include "ukbd.h"
42 #include "wsdisplay.h"
43
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/bus.h>
47 #include <sys/atomic.h>
48 #include <sys/cpu.h>
49 #include <sys/device.h>
50 #include <sys/exec.h>
51 #include <sys/kernel.h>
52 #include <sys/kmem.h>
53 #include <sys/ksyms.h>
54 #include <sys/msgbuf.h>
55 #include <sys/proc.h>
56 #include <sys/reboot.h>
57 #include <sys/termios.h>
58 #include <sys/bootblock.h>
59 #include <sys/disklabel.h>
60 #include <sys/vnode.h>
61 #include <sys/kauth.h>
62 #include <sys/fcntl.h>
63 #include <sys/md5.h>
64
65 #include <dev/cons.h>
66 #include <uvm/uvm_extern.h>
67
68 #include <sys/conf.h>
69
70 #include <machine/db_machdep.h>
71 #include <ddb/db_sym.h>
72 #include <ddb/db_extern.h>
73
74 #include <machine/bootconfig.h>
75 #include <arm/armreg.h>
76
77 #include <arm/cpufunc.h>
78
79 #include <evbarm/include/autoconf.h>
80 #include <evbarm/fdt/machdep.h>
81 #include <evbarm/fdt/platform.h>
82 #include <evbarm/fdt/fdt_memory.h>
83
84 #include <arm/fdt/arm_fdtvar.h>
85
86 #ifdef EFI_RUNTIME
87 #include <arm/arm/efi_runtime.h>
88 #endif
89
90 #if NUKBD > 0
91 #include <dev/usb/ukbdvar.h>
92 #endif
93 #if NWSDISPLAY > 0
94 #include <dev/wscons/wsdisplayvar.h>
95 #endif
96
97 #ifdef MEMORY_DISK_DYNAMIC
98 #include <dev/md.h>
99 #endif
100
101 #ifndef FDT_MAX_BOOT_STRING
102 #define FDT_MAX_BOOT_STRING 1024
103 #endif
104
105 BootConfig bootconfig;
106 char bootargs[FDT_MAX_BOOT_STRING] = "";
107 char *boot_args = NULL;
108
109 /* filled in before cleaning bss. keep in .data */
110 u_long uboot_args[4] __attribute__((__section__(".data")));
111 const uint8_t *fdt_addr_r __attribute__((__section__(".data")));
112
113 static uint64_t initrd_start, initrd_end;
114
115 #include <libfdt.h>
116 #include <dev/fdt/fdtvar.h>
117 #define FDT_BUF_SIZE (512*1024)
118 static uint8_t fdt_data[FDT_BUF_SIZE];
119
120 extern char KERNEL_BASE_phys[];
121 #define KERNEL_BASE_PHYS ((paddr_t)KERNEL_BASE_phys)
122
123 static void fdt_update_stdout_path(void);
124 static void fdt_device_register(device_t, void *);
125 static void fdt_device_register_post_config(device_t, void *);
126 static void fdt_cpu_rootconf(void);
127 static void fdt_reset(void);
128 static void fdt_powerdown(void);
129
130 static dev_type_cnputc(earlyconsputc);
131 static dev_type_cngetc(earlyconsgetc);
132
133 static struct consdev earlycons = {
134 .cn_putc = earlyconsputc,
135 .cn_getc = earlyconsgetc,
136 .cn_pollc = nullcnpollc,
137 };
138
139 static void
140 earlyconsputc(dev_t dev, int c)
141 {
142 uartputc(c);
143 }
144
145 static int
146 earlyconsgetc(dev_t dev)
147 {
148 return 0; /* XXX */
149 }
150
151 #ifdef VERBOSE_INIT_ARM
152 #define VPRINTF(...) printf(__VA_ARGS__)
153 #else
154 #define VPRINTF(...) __nothing
155 #endif
156
157 /*
158 * ARM: Get the first physically contiguous region of memory.
159 * ARM64: Get all of physical memory, including holes.
160 */
161 static void
162 fdt_get_memory(uint64_t *pstart, uint64_t *pend)
163 {
164 const int memory = OF_finddevice("/memory");
165 uint64_t cur_addr, cur_size;
166 int index;
167
168 /* Assume the first entry is the start of memory */
169 if (fdtbus_get_reg64(memory, 0, &cur_addr, &cur_size) != 0)
170 panic("Cannot determine memory size");
171
172 *pstart = cur_addr;
173 *pend = cur_addr + cur_size;
174
175 VPRINTF("FDT /memory [%d] @ 0x%" PRIx64 " size 0x%" PRIx64 "\n",
176 0, *pstart, *pend - *pstart);
177
178 for (index = 1;
179 fdtbus_get_reg64(memory, index, &cur_addr, &cur_size) == 0;
180 index++) {
181 VPRINTF("FDT /memory [%d] @ 0x%" PRIx64 " size 0x%" PRIx64 "\n",
182 index, cur_addr, cur_size);
183
184 #ifdef __aarch64__
185 if (cur_addr + cur_size > *pend)
186 *pend = cur_addr + cur_size;
187 #else
188 /* If subsequent entries follow the previous, append them. */
189 if (*pend == cur_addr)
190 *pend = cur_addr + cur_size;
191 #endif
192 }
193 }
194
195 void
196 fdt_add_reserved_memory_range(uint64_t addr, uint64_t size)
197 {
198 fdt_memory_remove_range(addr, size);
199 }
200
201 /*
202 * Exclude memory ranges from memory config from the device tree
203 */
204 static void
205 fdt_add_reserved_memory(uint64_t min_addr, uint64_t max_addr)
206 {
207 uint64_t lstart = 0, lend = 0;
208 uint64_t addr, size;
209 int index, error;
210
211 const int num = fdt_num_mem_rsv(fdtbus_get_data());
212 for (index = 0; index <= num; index++) {
213 error = fdt_get_mem_rsv(fdtbus_get_data(), index,
214 &addr, &size);
215 if (error != 0)
216 continue;
217 if (lstart <= addr && addr <= lend) {
218 size -= (lend - addr);
219 addr = lend;
220 }
221 if (size == 0)
222 continue;
223 if (addr + size <= min_addr)
224 continue;
225 if (addr >= max_addr)
226 continue;
227 if (addr < min_addr) {
228 size -= (min_addr - addr);
229 addr = min_addr;
230 }
231 if (addr + size > max_addr)
232 size = max_addr - addr;
233 fdt_add_reserved_memory_range(addr, size);
234 lstart = addr;
235 lend = addr + size;
236 }
237 }
238
239 static void
240 fdt_add_dram_blocks(const struct fdt_memory *m, void *arg)
241 {
242 BootConfig *bc = arg;
243
244 VPRINTF(" %lx - %lx\n", m->start, m->end - 1);
245 bc->dram[bc->dramblocks].address = m->start;
246 bc->dram[bc->dramblocks].pages =
247 (m->end - m->start) / PAGE_SIZE;
248 bc->dramblocks++;
249 }
250
251 #define MAX_PHYSMEM 64
252 static int nfdt_physmem = 0;
253 static struct boot_physmem fdt_physmem[MAX_PHYSMEM];
254
255 static void
256 fdt_add_boot_physmem(const struct fdt_memory *m, void *arg)
257 {
258 struct boot_physmem *bp = &fdt_physmem[nfdt_physmem++];
259
260 VPRINTF(" %lx - %lx\n", m->start, m->end - 1);
261
262 KASSERT(nfdt_physmem <= MAX_PHYSMEM);
263
264 bp->bp_start = atop(round_page(m->start));
265 bp->bp_pages = atop(trunc_page(m->end)) - bp->bp_start;
266 bp->bp_freelist = VM_FREELIST_DEFAULT;
267
268 #ifdef _LP64
269 if (m->end > 0x100000000)
270 bp->bp_freelist = VM_FREELIST_HIGHMEM;
271 #endif
272
273 #ifdef PMAP_NEED_ALLOC_POOLPAGE
274 const uint64_t memory_size = *(uint64_t *)arg;
275 if (atop(memory_size) > bp->bp_pages) {
276 arm_poolpage_vmfreelist = VM_FREELIST_DIRECTMAP;
277 bp->bp_freelist = VM_FREELIST_DIRECTMAP;
278 }
279 #endif
280 }
281
282 /*
283 * Define usable memory regions.
284 */
285 static void
286 fdt_build_bootconfig(uint64_t mem_start, uint64_t mem_end)
287 {
288 const int memory = OF_finddevice("/memory");
289 BootConfig *bc = &bootconfig;
290 uint64_t addr, size;
291 int index;
292
293 for (index = 0;
294 fdtbus_get_reg64(memory, index, &addr, &size) == 0;
295 index++) {
296 if (addr >= mem_end || size == 0)
297 continue;
298 if (addr + size > mem_end)
299 size = mem_end - addr;
300
301 fdt_memory_add_range(addr, size);
302 }
303
304 fdt_add_reserved_memory(mem_start, mem_end);
305
306 const uint64_t initrd_size = initrd_end - initrd_start;
307 if (initrd_size > 0)
308 fdt_memory_remove_range(initrd_start, initrd_size);
309
310 const int framebuffer = OF_finddevice("/chosen/framebuffer");
311 if (framebuffer >= 0) {
312 for (index = 0;
313 fdtbus_get_reg64(framebuffer, index, &addr, &size) == 0;
314 index++) {
315 fdt_add_reserved_memory_range(addr, size);
316 }
317 }
318
319 VPRINTF("Usable memory:\n");
320 bc->dramblocks = 0;
321 fdt_memory_foreach(fdt_add_dram_blocks, bc);
322 }
323
324 static void
325 fdt_probe_initrd(uint64_t *pstart, uint64_t *pend)
326 {
327 *pstart = *pend = 0;
328
329 #ifdef MEMORY_DISK_DYNAMIC
330 const int chosen = OF_finddevice("/chosen");
331 if (chosen < 0)
332 return;
333
334 int len;
335 const void *start_data = fdtbus_get_prop(chosen,
336 "linux,initrd-start", &len);
337 const void *end_data = fdtbus_get_prop(chosen,
338 "linux,initrd-end", NULL);
339 if (start_data == NULL || end_data == NULL)
340 return;
341
342 switch (len) {
343 case 4:
344 *pstart = be32dec(start_data);
345 *pend = be32dec(end_data);
346 break;
347 case 8:
348 *pstart = be64dec(start_data);
349 *pend = be64dec(end_data);
350 break;
351 default:
352 printf("Unsupported len %d for /chosen/initrd-start\n", len);
353 return;
354 }
355 #endif
356 }
357
358 static void
359 fdt_setup_initrd(void)
360 {
361 #ifdef MEMORY_DISK_DYNAMIC
362 const uint64_t initrd_size = initrd_end - initrd_start;
363 paddr_t startpa = trunc_page(initrd_start);
364 paddr_t endpa = round_page(initrd_end);
365 paddr_t pa;
366 vaddr_t va;
367 void *md_start;
368
369 if (initrd_size == 0)
370 return;
371
372 va = uvm_km_alloc(kernel_map, initrd_size, 0,
373 UVM_KMF_VAONLY | UVM_KMF_NOWAIT);
374 if (va == 0) {
375 printf("Failed to allocate VA for initrd\n");
376 return;
377 }
378
379 md_start = (void *)va;
380
381 for (pa = startpa; pa < endpa; pa += PAGE_SIZE, va += PAGE_SIZE)
382 pmap_kenter_pa(va, pa, VM_PROT_READ|VM_PROT_WRITE, 0);
383 pmap_update(pmap_kernel());
384
385 md_root_setconf(md_start, initrd_size);
386 #endif
387 }
388
389 #ifdef EFI_RUNTIME
390 static void
391 fdt_map_efi_runtime(const char *prop, bool exec)
392 {
393 int len;
394
395 const int chosen_off = fdt_path_offset(fdt_data, "/chosen");
396 if (chosen_off < 0)
397 return;
398
399 const uint64_t *map = fdt_getprop(fdt_data, chosen_off, prop, &len);
400 if (map == NULL)
401 return;
402
403 while (len >= 24) {
404 const paddr_t pa = be64toh(map[0]);
405 const vaddr_t va = be64toh(map[1]);
406 const uint64_t sz = be64toh(map[2]);
407 arm_efirt_md_map_range(va, pa, sz, exec);
408 map += 3;
409 len -= 24;
410 }
411 }
412 #endif
413
414 u_int initarm(void *arg);
415
416 u_int
417 initarm(void *arg)
418 {
419 const struct arm_platform *plat;
420 uint64_t memory_start, memory_end;
421
422 /* set temporally to work printf()/panic() even before consinit() */
423 cn_tab = &earlycons;
424
425 /* Load FDT */
426 int error = fdt_check_header(fdt_addr_r);
427 if (error == 0) {
428 /* If the DTB is too big, try to pack it in place first. */
429 if (fdt_totalsize(fdt_addr_r) > sizeof(fdt_data))
430 (void)fdt_pack(__UNCONST(fdt_addr_r));
431 error = fdt_open_into(fdt_addr_r, fdt_data, sizeof(fdt_data));
432 if (error != 0)
433 panic("fdt_move failed: %s", fdt_strerror(error));
434 fdtbus_set_data(fdt_data);
435 } else {
436 panic("fdt_check_header failed: %s", fdt_strerror(error));
437 }
438
439 /* Lookup platform specific backend */
440 plat = arm_fdt_platform();
441 if (plat == NULL)
442 panic("Kernel does not support this device");
443
444 /* Early console may be available, announce ourselves. */
445 VPRINTF("FDT<%p>\n", fdt_addr_r);
446
447 const int chosen = OF_finddevice("/chosen");
448 if (chosen >= 0)
449 OF_getprop(chosen, "bootargs", bootargs, sizeof(bootargs));
450 boot_args = bootargs;
451
452 /* Heads up ... Setup the CPU / MMU / TLB functions. */
453 VPRINTF("cpufunc\n");
454 if (set_cpufuncs())
455 panic("cpu not recognized!");
456
457 /*
458 * Memory is still identity/flat mapped this point so using ttbr for
459 * l1pt VA is fine
460 */
461
462 VPRINTF("devmap\n");
463 extern char ARM_BOOTSTRAP_LxPT[];
464 pmap_devmap_bootstrap((vaddr_t)ARM_BOOTSTRAP_LxPT, plat->ap_devmap());
465
466 VPRINTF("bootstrap\n");
467 plat->ap_bootstrap();
468
469 /*
470 * If stdout-path is specified on the command line, override the
471 * value in /chosen/stdout-path before initializing console.
472 */
473 VPRINTF("stdout\n");
474 fdt_update_stdout_path();
475
476 /*
477 * Done making changes to the FDT.
478 */
479 fdt_pack(fdt_data);
480
481 VPRINTF("consinit ");
482 consinit();
483 VPRINTF("ok\n");
484
485 VPRINTF("uboot: args %#lx, %#lx, %#lx, %#lx\n",
486 uboot_args[0], uboot_args[1], uboot_args[2], uboot_args[3]);
487
488 cpu_reset_address = fdt_reset;
489 cpu_powerdown_address = fdt_powerdown;
490 evbarm_device_register = fdt_device_register;
491 evbarm_device_register_post_config = fdt_device_register_post_config;
492 evbarm_cpu_rootconf = fdt_cpu_rootconf;
493
494 /* Talk to the user */
495 printf("NetBSD/evbarm (fdt) booting ...\n");
496
497 #ifdef BOOT_ARGS
498 char mi_bootargs[] = BOOT_ARGS;
499 parse_mi_bootargs(mi_bootargs);
500 #endif
501
502 fdt_get_memory(&memory_start, &memory_end);
503
504 #if !defined(_LP64)
505 /* Cannot map memory above 4GB */
506 if (memory_end >= 0x100000000ULL)
507 memory_end = 0x100000000ULL - PAGE_SIZE;
508
509 #endif
510 uint64_t memory_size = memory_end - memory_start;
511
512 VPRINTF("%s: memory start %" PRIx64 " end %" PRIx64 " (len %"
513 PRIx64 ")\n", __func__, memory_start, memory_end, memory_size);
514
515 /* Parse ramdisk info */
516 fdt_probe_initrd(&initrd_start, &initrd_end);
517
518 /*
519 * Populate bootconfig structure for the benefit of
520 * dodumpsys
521 */
522 VPRINTF("%s: fdt_build_bootconfig\n", __func__);
523 fdt_build_bootconfig(memory_start, memory_end);
524
525 #ifdef EFI_RUNTIME
526 fdt_map_efi_runtime("netbsd,uefi-runtime-code", true);
527 fdt_map_efi_runtime("netbsd,uefi-runtime-data", false);
528 #endif
529
530 /* Perform PT build and VM init */
531 cpu_kernel_vm_init(memory_start, memory_size);
532
533 VPRINTF("bootargs: %s\n", bootargs);
534
535 parse_mi_bootargs(boot_args);
536
537 VPRINTF("Memory regions:\n");
538 fdt_memory_foreach(fdt_add_boot_physmem, &memory_size);
539
540 u_int sp = initarm_common(KERNEL_VM_BASE, KERNEL_VM_SIZE, fdt_physmem,
541 nfdt_physmem);
542
543 VPRINTF("mpstart\n");
544 if (plat->ap_mpstart)
545 plat->ap_mpstart();
546
547 /*
548 * Now we have APs started the pages used for stacks and L1PT can
549 * be given to uvm
550 */
551 extern char __start__init_memory[], __stop__init_memory[];
552 if (__start__init_memory != __stop__init_memory) {
553 const paddr_t spa = KERN_VTOPHYS((vaddr_t)__start__init_memory);
554 const paddr_t epa = KERN_VTOPHYS((vaddr_t)__stop__init_memory);
555 const paddr_t spg = atop(spa);
556 const paddr_t epg = atop(epa);
557
558 uvm_page_physload(spg, epg, spg, epg, VM_FREELIST_DEFAULT);
559
560 VPRINTF(" start %08lx end %08lx", ptoa(spa), ptoa(epa));
561 }
562
563 return sp;
564 }
565
566 static void
567 fdt_update_stdout_path(void)
568 {
569 char *stdout_path, *ep;
570 int stdout_path_len;
571 char buf[256];
572
573 const int chosen_off = fdt_path_offset(fdt_data, "/chosen");
574 if (chosen_off == -1)
575 return;
576
577 if (get_bootconf_option(boot_args, "stdout-path",
578 BOOTOPT_TYPE_STRING, &stdout_path) == 0)
579 return;
580
581 ep = strchr(stdout_path, ' ');
582 stdout_path_len = ep ? (ep - stdout_path) : strlen(stdout_path);
583 if (stdout_path_len >= sizeof(buf))
584 return;
585
586 strncpy(buf, stdout_path, stdout_path_len);
587 buf[stdout_path_len] = '\0';
588 fdt_setprop(fdt_data, chosen_off, "stdout-path",
589 buf, stdout_path_len + 1);
590 }
591
592 void
593 consinit(void)
594 {
595 static bool initialized = false;
596 const struct arm_platform *plat = arm_fdt_platform();
597 const struct fdt_console *cons = fdtbus_get_console();
598 struct fdt_attach_args faa;
599 u_int uart_freq = 0;
600
601 if (initialized || cons == NULL)
602 return;
603
604 plat->ap_init_attach_args(&faa);
605 faa.faa_phandle = fdtbus_get_stdout_phandle();
606
607 if (plat->ap_uart_freq != NULL)
608 uart_freq = plat->ap_uart_freq();
609
610 cons->consinit(&faa, uart_freq);
611
612 initialized = true;
613 }
614
615 void
616 delay(u_int us)
617 {
618 const struct arm_platform *plat = arm_fdt_platform();
619
620 plat->ap_delay(us);
621 }
622
623 static void
624 fdt_detect_root_device(device_t dev)
625 {
626 struct mbr_sector mbr;
627 uint8_t buf[DEV_BSIZE];
628 uint8_t hash[16];
629 const uint8_t *rhash;
630 char rootarg[32];
631 struct vnode *vp;
632 MD5_CTX md5ctx;
633 int error, len;
634 size_t resid;
635 u_int part;
636
637 const int chosen = OF_finddevice("/chosen");
638 if (chosen < 0)
639 return;
640
641 if (of_hasprop(chosen, "netbsd,mbr") &&
642 of_hasprop(chosen, "netbsd,partition")) {
643
644 /*
645 * The bootloader has passed in a partition index and MD5 hash
646 * of the MBR sector. Read the MBR of this device, calculate the
647 * hash, and compare it with the value passed in.
648 */
649 rhash = fdtbus_get_prop(chosen, "netbsd,mbr", &len);
650 if (rhash == NULL || len != 16)
651 return;
652 of_getprop_uint32(chosen, "netbsd,partition", &part);
653 if (part >= MAXPARTITIONS)
654 return;
655
656 vp = opendisk(dev);
657 if (!vp)
658 return;
659 error = vn_rdwr(UIO_READ, vp, buf, sizeof(buf), 0, UIO_SYSSPACE,
660 0, NOCRED, &resid, NULL);
661 VOP_CLOSE(vp, FREAD, NOCRED);
662 vput(vp);
663
664 if (error != 0)
665 return;
666
667 memcpy(&mbr, buf, sizeof(mbr));
668 MD5Init(&md5ctx);
669 MD5Update(&md5ctx, (void *)&mbr, sizeof(mbr));
670 MD5Final(hash, &md5ctx);
671
672 if (memcmp(rhash, hash, 16) != 0)
673 return;
674
675 snprintf(rootarg, sizeof(rootarg), " root=%s%c", device_xname(dev), part + 'a');
676 strcat(boot_args, rootarg);
677 }
678 }
679
680 static void
681 fdt_device_register(device_t self, void *aux)
682 {
683 const struct arm_platform *plat = arm_fdt_platform();
684
685 if (device_is_a(self, "armfdt"))
686 fdt_setup_initrd();
687
688 if (plat && plat->ap_device_register)
689 plat->ap_device_register(self, aux);
690 }
691
692 static void
693 fdt_device_register_post_config(device_t self, void *aux)
694 {
695 #if NUKBD > 0 && NWSDISPLAY > 0
696 if (device_is_a(self, "wsdisplay")) {
697 struct wsdisplay_softc *sc = device_private(self);
698 if (wsdisplay_isconsole(sc))
699 ukbd_cnattach();
700 }
701 #endif
702 }
703
704 static void
705 fdt_cpu_rootconf(void)
706 {
707 device_t dev;
708 deviter_t di;
709 char *ptr;
710
711 for (dev = deviter_first(&di, 0); dev; dev = deviter_next(&di)) {
712 if (device_class(dev) != DV_DISK)
713 continue;
714
715 if (get_bootconf_option(boot_args, "root", BOOTOPT_TYPE_STRING, &ptr) != 0)
716 break;
717
718 if (device_is_a(dev, "ld") || device_is_a(dev, "sd") || device_is_a(dev, "wd"))
719 fdt_detect_root_device(dev);
720 }
721 deviter_release(&di);
722 }
723
724 static void
725 fdt_reset(void)
726 {
727 const struct arm_platform *plat = arm_fdt_platform();
728
729 fdtbus_power_reset();
730
731 if (plat && plat->ap_reset)
732 plat->ap_reset();
733 }
734
735 static void
736 fdt_powerdown(void)
737 {
738 fdtbus_power_poweroff();
739 }
740