xref: /netbsd-src/sys/arch/evbarm/fdt/fdt_machdep.c (revision d16b7486a53dcb8072b60ec6fcb4373a2d0c27b7)
1 /* $NetBSD: fdt_machdep.c,v 1.106 2023/08/04 09:06:33 mrg Exp $ */
2 
3 /*-
4  * Copyright (c) 2015-2017 Jared McNeill <jmcneill@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 1.106 2023/08/04 09:06:33 mrg Exp $");
31 
32 #include "opt_arm_debug.h"
33 #include "opt_bootconfig.h"
34 #include "opt_cpuoptions.h"
35 #include "opt_ddb.h"
36 #include "opt_efi.h"
37 #include "opt_machdep.h"
38 #include "opt_multiprocessor.h"
39 
40 #include "genfb.h"
41 #include "ukbd.h"
42 #include "wsdisplay.h"
43 
44 #include <sys/param.h>
45 #include <sys/types.h>
46 
47 #include <sys/atomic.h>
48 #include <sys/bootblock.h>
49 #include <sys/bus.h>
50 #include <sys/conf.h>
51 #include <sys/cpu.h>
52 #include <sys/device.h>
53 #include <sys/disk.h>
54 #include <sys/disklabel.h>
55 #include <sys/endian.h>
56 #include <sys/exec.h>
57 #include <sys/fcntl.h>
58 #include <sys/kauth.h>
59 #include <sys/kernel.h>
60 #include <sys/kmem.h>
61 #include <sys/ksyms.h>
62 #include <sys/md5.h>
63 #include <sys/msgbuf.h>
64 #include <sys/proc.h>
65 #include <sys/pserialize.h>
66 #include <sys/reboot.h>
67 #include <sys/systm.h>
68 #include <sys/termios.h>
69 #include <sys/vnode.h>
70 #include <sys/uuid.h>
71 
72 #include <net/if.h>
73 #include <net/if_dl.h>
74 
75 #include <dev/cons.h>
76 #include <uvm/uvm_extern.h>
77 
78 #include <machine/db_machdep.h>
79 #include <ddb/db_sym.h>
80 #include <ddb/db_extern.h>
81 
82 #include <machine/bootconfig.h>
83 #include <arm/armreg.h>
84 
85 #include <arm/cpufunc.h>
86 
87 #include <evbarm/include/autoconf.h>
88 #include <evbarm/fdt/machdep.h>
89 #include <evbarm/fdt/platform.h>
90 
91 #include <arm/fdt/arm_fdtvar.h>
92 
93 #include <dev/fdt/fdtvar.h>
94 #include <dev/fdt/fdt_boot.h>
95 #include <dev/fdt/fdt_private.h>
96 #include <dev/fdt/fdt_memory.h>
97 
98 #ifdef EFI_RUNTIME
99 #include <arm/arm/efi_runtime.h>
100 #endif
101 
102 #if NWSDISPLAY > 0 && NGENFB > 0
103 #include <arm/fdt/arm_simplefb.h>
104 #endif
105 
106 #if NUKBD > 0
107 #include <dev/usb/ukbdvar.h>
108 #endif
109 #if NWSDISPLAY > 0
110 #include <dev/wscons/wsdisplayvar.h>
111 #endif
112 
113 BootConfig bootconfig;
114 char *boot_args = NULL;
115 
116 /* filled in before cleaning bss. keep in .data */
117 u_long uboot_args[4] __attribute__((__section__(".data")));
118 const uint8_t *fdt_addr_r __attribute__((__section__(".data")));
119 
120 #include <libfdt.h>
121 #include <dev/fdt/fdtvar.h>
122 #define FDT_BUF_SIZE	(512*1024)
123 static uint8_t fdt_data[FDT_BUF_SIZE];
124 
125 extern char KERNEL_BASE_phys[];
126 #define KERNEL_BASE_PHYS ((paddr_t)KERNEL_BASE_phys)
127 
128 static void fdt_device_register(device_t, void *);
129 static void fdt_device_register_post_config(device_t, void *);
130 static void fdt_cpu_rootconf(void);
131 static void fdt_reset(void);
132 static void fdt_powerdown(void);
133 
134 #if BYTE_ORDER == BIG_ENDIAN
135 static void fdt_update_fb_format(void);
136 #endif
137 
138 static void
139 earlyconsputc(dev_t dev, int c)
140 {
141 	uartputc(c);
142 }
143 
144 static int
145 earlyconsgetc(dev_t dev)
146 {
147 	return -1;
148 }
149 
150 static struct consdev earlycons = {
151 	.cn_putc = earlyconsputc,
152 	.cn_getc = earlyconsgetc,
153 	.cn_pollc = nullcnpollc,
154 };
155 
156 #ifdef VERBOSE_INIT_ARM
157 #define VPRINTF(...)	printf(__VA_ARGS__)
158 #else
159 #define VPRINTF(...)	__nothing
160 #endif
161 
162 static void
163 fdt_add_dram_blocks(const struct fdt_memory *m, void *arg)
164 {
165 	BootConfig *bc = arg;
166 
167 	VPRINTF("  %" PRIx64 " - %" PRIx64 "\n", m->start, m->end - 1);
168 	bc->dram[bc->dramblocks].address = m->start;
169 	bc->dram[bc->dramblocks].pages =
170 	    (m->end - m->start) / PAGE_SIZE;
171 	bc->dramblocks++;
172 }
173 
174 static int nfdt_physmem = 0;
175 static struct boot_physmem fdt_physmem[FDT_MEMORY_RANGES];
176 
177 static void
178 fdt_add_boot_physmem(const struct fdt_memory *m, void *arg)
179 {
180 	const paddr_t saddr = round_page(m->start);
181 	const paddr_t eaddr = trunc_page(m->end);
182 
183 	VPRINTF("  %" PRIx64 " - %" PRIx64, m->start, m->end - 1);
184 	if (saddr >= eaddr) {
185 		VPRINTF(" skipped\n");
186 		return;
187 	}
188 	VPRINTF("\n");
189 
190 	struct boot_physmem *bp = &fdt_physmem[nfdt_physmem++];
191 
192 	KASSERT(nfdt_physmem <= FDT_MEMORY_RANGES);
193 
194 	bp->bp_start = atop(saddr);
195 	bp->bp_pages = atop(eaddr) - bp->bp_start;
196 	bp->bp_freelist = VM_FREELIST_DEFAULT;
197 
198 #ifdef PMAP_NEED_ALLOC_POOLPAGE
199 	const uint64_t memory_size = *(uint64_t *)arg;
200 	if (atop(memory_size) > bp->bp_pages) {
201 		arm_poolpage_vmfreelist = VM_FREELIST_DIRECTMAP;
202 		bp->bp_freelist = VM_FREELIST_DIRECTMAP;
203 	}
204 #endif
205 }
206 
207 
208 static void
209 fdt_print_memory(const struct fdt_memory *m, void *arg)
210 {
211 
212 	VPRINTF("FDT /memory @ 0x%" PRIx64 " size 0x%" PRIx64 "\n",
213 	    m->start, m->end - m->start);
214 }
215 
216 
217 /*
218  * Define usable memory regions.
219  */
220 static void
221 fdt_build_bootconfig(uint64_t mem_start, uint64_t mem_end)
222 {
223 	BootConfig *bc = &bootconfig;
224 
225 	uint64_t addr, size;
226 	int index;
227 
228 	/* Reserve pages for ramdisk, rndseed, and firmware's RNG */
229 	fdt_reserve_initrd();
230 	fdt_reserve_rndseed();
231 	fdt_reserve_efirng();
232 
233 	const int framebuffer = OF_finddevice("/chosen/framebuffer");
234 	if (framebuffer >= 0) {
235 		for (index = 0;
236 		     fdtbus_get_reg64(framebuffer, index, &addr, &size) == 0;
237 		     index++) {
238 			fdt_memory_remove_range(addr, size);
239 		}
240 	}
241 
242 	VPRINTF("Usable memory:\n");
243 	bc->dramblocks = 0;
244 	fdt_memory_foreach(fdt_add_dram_blocks, bc);
245 }
246 
247 
248 vaddr_t
249 initarm(void *arg)
250 {
251 	const struct fdt_platform *plat;
252 	uint64_t memory_start, memory_end;
253 
254 	/* set temporally to work printf()/panic() even before consinit() */
255 	cn_tab = &earlycons;
256 
257 	/* Load FDT */
258 	int error = fdt_check_header(fdt_addr_r);
259 	if (error != 0)
260 		panic("fdt_check_header failed: %s", fdt_strerror(error));
261 
262 	/* If the DTB is too big, try to pack it in place first. */
263 	if (fdt_totalsize(fdt_addr_r) > sizeof(fdt_data))
264 		(void)fdt_pack(__UNCONST(fdt_addr_r));
265 
266 	error = fdt_open_into(fdt_addr_r, fdt_data, sizeof(fdt_data));
267 	if (error != 0)
268 		panic("fdt_move failed: %s", fdt_strerror(error));
269 
270 	fdtbus_init(fdt_data);
271 
272 	/* Lookup platform specific backend */
273 	plat = fdt_platform_find();
274 	if (plat == NULL)
275 		panic("Kernel does not support this device");
276 
277 	/* Early console may be available, announce ourselves. */
278 	VPRINTF("FDT<%p>\n", fdt_addr_r);
279 
280 	boot_args = fdt_get_bootargs();
281 
282 	/* Heads up ... Setup the CPU / MMU / TLB functions. */
283 	VPRINTF("cpufunc\n");
284 	if (set_cpufuncs())
285 		panic("cpu not recognized!");
286 
287 	/*
288 	 * Memory is still identity/flat mapped this point so using ttbr for
289 	 * l1pt VA is fine
290 	 */
291 
292 	VPRINTF("devmap %p\n", plat->fp_devmap());
293 	extern char ARM_BOOTSTRAP_LxPT[];
294 	pmap_devmap_bootstrap((vaddr_t)ARM_BOOTSTRAP_LxPT, plat->fp_devmap());
295 
296 	VPRINTF("bootstrap\n");
297 	plat->fp_bootstrap();
298 
299 	/*
300 	 * If stdout-path is specified on the command line, override the
301 	 * value in /chosen/stdout-path before initializing console.
302 	 */
303 	VPRINTF("stdout\n");
304 	fdt_update_stdout_path(fdt_data, boot_args);
305 
306 #if BYTE_ORDER == BIG_ENDIAN
307 	/*
308 	 * Most boards are configured to little-endian mode initially, and
309 	 * switched to big-endian mode after kernel is loaded. In this case,
310 	 * framebuffer seems byte-swapped to CPU. Override FDT to let
311 	 * drivers know.
312 	 */
313 	VPRINTF("fb_format\n");
314 	fdt_update_fb_format();
315 #endif
316 
317 	/*
318 	 * Done making changes to the FDT.
319 	 */
320 	fdt_pack(fdt_data);
321 
322 	VPRINTF("consinit ");
323 	consinit();
324 	VPRINTF("ok\n");
325 
326 	VPRINTF("uboot: args %#lx, %#lx, %#lx, %#lx\n",
327 	    uboot_args[0], uboot_args[1], uboot_args[2], uboot_args[3]);
328 
329 	cpu_reset_address = fdt_reset;
330 	cpu_powerdown_address = fdt_powerdown;
331 	evbarm_device_register = fdt_device_register;
332 	evbarm_device_register_post_config = fdt_device_register_post_config;
333 	evbarm_cpu_rootconf = fdt_cpu_rootconf;
334 
335 	/* Talk to the user */
336 	printf("NetBSD/evbarm (fdt) booting ...\n");
337 
338 #ifdef BOOT_ARGS
339 	char mi_bootargs[] = BOOT_ARGS;
340 	parse_mi_bootargs(mi_bootargs);
341 #endif
342 
343 	fdt_memory_get(&memory_start, &memory_end);
344 
345 	fdt_memory_foreach(fdt_print_memory, NULL);
346 
347 #if !defined(_LP64)
348 	/* Cannot map memory above 4GB (remove last page as well) */
349 	const uint64_t memory_limit = 0x100000000ULL - PAGE_SIZE;
350 	if (memory_end > memory_limit) {
351 		fdt_memory_remove_range(memory_limit , memory_end);
352 		memory_end = memory_limit;
353 	}
354 #endif
355 	uint64_t memory_size = memory_end - memory_start;
356 
357 	VPRINTF("%s: memory start %" PRIx64 " end %" PRIx64 " (len %"
358 	    PRIx64 ")\n", __func__, memory_start, memory_end, memory_size);
359 
360 	/* Parse ramdisk info */
361 	fdt_probe_initrd();
362 
363 	/* Parse our on-disk rndseed and the firmware's RNG from EFI */
364 	fdt_probe_rndseed();
365 	fdt_probe_efirng();
366 
367 	fdt_memory_remove_reserved(memory_start, memory_end);
368 
369 	/*
370 	 * Populate bootconfig structure for the benefit of dodumpsys
371 	 */
372 	VPRINTF("%s: fdt_build_bootconfig\n", __func__);
373 	fdt_build_bootconfig(memory_start, memory_end);
374 
375 	/* Perform PT build and VM init */
376 	cpu_kernel_vm_init(memory_start, memory_size);
377 
378 	VPRINTF("bootargs: %s\n", boot_args);
379 
380 	parse_mi_bootargs(boot_args);
381 
382 	VPRINTF("Memory regions:\n");
383 
384 	/* Populate fdt_physmem / nfdt_physmem for initarm_common */
385 	fdt_memory_foreach(fdt_add_boot_physmem, &memory_size);
386 
387 	vaddr_t sp = initarm_common(KERNEL_VM_BASE, KERNEL_VM_SIZE, fdt_physmem,
388 	     nfdt_physmem);
389 
390 	/*
391 	 * initarm_common flushes cache if required before AP start
392 	 */
393 	error = 0;
394 	if ((boothowto & RB_MD1) == 0) {
395 		VPRINTF("mpstart\n");
396 		if (plat->fp_mpstart)
397 			error = plat->fp_mpstart();
398 	}
399 
400 	if (error)
401 		return sp;
402 
403 	/*
404 	 * Now we have APs started the pages used for stacks and L1PT can
405 	 * be given to uvm
406 	 */
407 	extern char const __start__init_memory[];
408 	extern char const __stop__init_memory[] __weak;
409 
410 	if (&__start__init_memory[0] != &__stop__init_memory[0]) {
411 		const paddr_t spa = KERN_VTOPHYS((vaddr_t)__start__init_memory);
412 		const paddr_t epa = KERN_VTOPHYS((vaddr_t)__stop__init_memory);
413 		const paddr_t spg = atop(spa);
414 		const paddr_t epg = atop(epa);
415 
416 		VPRINTF("         start %08lx  end %08lx... "
417 		    "loading in freelist %d\n", spa, epa, VM_FREELIST_DEFAULT);
418 
419 		uvm_page_physload(spg, epg, spg, epg, VM_FREELIST_DEFAULT);
420 	}
421 
422 	return sp;
423 }
424 
425 void
426 consinit(void)
427 {
428 	static bool initialized = false;
429 	const struct fdt_platform *plat = fdt_platform_find();
430 	const struct fdt_console *cons = fdtbus_get_console();
431 	struct fdt_attach_args faa;
432 	u_int uart_freq = 0;
433 
434 	if (initialized || cons == NULL)
435 		return;
436 
437 	plat->fp_init_attach_args(&faa);
438 	faa.faa_phandle = fdtbus_get_stdout_phandle();
439 
440 	if (plat->fp_uart_freq != NULL)
441 		uart_freq = plat->fp_uart_freq();
442 
443 	cons->consinit(&faa, uart_freq);
444 
445 	initialized = true;
446 }
447 
448 void
449 cpu_startup_hook(void)
450 {
451 #ifdef EFI_RUNTIME
452 	fdt_map_efi_runtime("netbsd,uefi-runtime-code", ARM_EFIRT_MEM_CODE);
453 	fdt_map_efi_runtime("netbsd,uefi-runtime-data", ARM_EFIRT_MEM_DATA);
454 	fdt_map_efi_runtime("netbsd,uefi-runtime-mmio", ARM_EFIRT_MEM_MMIO);
455 #endif
456 
457 	fdtbus_intr_init();
458 
459 	fdt_setup_rndseed();
460 	fdt_setup_efirng();
461 }
462 
463 void
464 delay(u_int us)
465 {
466 	const struct fdt_platform *plat = fdt_platform_find();
467 
468 	plat->fp_delay(us);
469 }
470 
471 static void
472 fdt_detect_root_device(device_t dev)
473 {
474 	int error, len;
475 
476 	const int chosen = OF_finddevice("/chosen");
477 	if (chosen < 0)
478 		return;
479 
480 	if (of_hasprop(chosen, "netbsd,mbr") &&
481 	    of_hasprop(chosen, "netbsd,partition")) {
482 		struct mbr_sector mbr;
483 		uint8_t buf[DEV_BSIZE];
484 		uint8_t hash[16];
485 		const uint8_t *rhash;
486 		struct vnode *vp;
487 		MD5_CTX md5ctx;
488 		size_t resid;
489 		u_int part;
490 
491 		/*
492 		 * The bootloader has passed in a partition index and MD5 hash
493 		 * of the MBR sector. Read the MBR of this device, calculate the
494 		 * hash, and compare it with the value passed in.
495 		 */
496 		rhash = fdtbus_get_prop(chosen, "netbsd,mbr", &len);
497 		if (rhash == NULL || len != 16)
498 			return;
499 		of_getprop_uint32(chosen, "netbsd,partition", &part);
500 		if (part >= MAXPARTITIONS)
501 			return;
502 
503 		vp = opendisk(dev);
504 		if (!vp)
505 			return;
506 		error = vn_rdwr(UIO_READ, vp, buf, sizeof(buf), 0, UIO_SYSSPACE,
507 		    IO_NODELOCKED, NOCRED, &resid, NULL);
508 		VOP_CLOSE(vp, FREAD, NOCRED);
509 		vput(vp);
510 
511 		if (error != 0)
512 			return;
513 
514 		memcpy(&mbr, buf, sizeof(mbr));
515 		MD5Init(&md5ctx);
516 		MD5Update(&md5ctx, (void *)&mbr, sizeof(mbr));
517 		MD5Final(hash, &md5ctx);
518 
519 		if (memcmp(rhash, hash, 16) == 0) {
520 			booted_device = dev;
521 			booted_partition = part;
522 		}
523 
524 		return;
525 	}
526 
527 	if (of_hasprop(chosen, "netbsd,gpt-guid")) {
528 		const struct uuid *guid =
529 		    fdtbus_get_prop(chosen, "netbsd,gpt-guid", &len);
530 
531 		if (guid == NULL || len != 16)
532 			return;
533 
534 		char guidstr[UUID_STR_LEN];
535 		uuid_snprintf(guidstr, sizeof(guidstr), guid);
536 
537 		device_t dv = dkwedge_find_by_wname(guidstr);
538 		if (dv != NULL)
539 			booted_device = dv;
540 
541 		return;
542 	}
543 
544 	if (of_hasprop(chosen, "netbsd,gpt-label")) {
545 		const char *label = fdtbus_get_string(chosen, "netbsd,gpt-label");
546 		if (label == NULL || *label == '\0')
547 			return;
548 
549 		device_t dv = dkwedge_find_by_wname(label);
550 		if (dv != NULL)
551 			booted_device = dv;
552 
553 		return;
554 	}
555 
556 	if (of_hasprop(chosen, "netbsd,booted-mac-address")) {
557 		const uint8_t *macaddr =
558 		    fdtbus_get_prop(chosen, "netbsd,booted-mac-address", &len);
559 		struct ifnet *ifp;
560 
561 		if (macaddr == NULL || len != 6)
562 			return;
563 
564 		int s = pserialize_read_enter();
565 		IFNET_READER_FOREACH(ifp) {
566 			if (memcmp(macaddr, CLLADDR(ifp->if_sadl), len) == 0) {
567 				device_t dv = device_find_by_xname(ifp->if_xname);
568 				if (dv != NULL)
569 					booted_device = dv;
570 				break;
571 			}
572 		}
573 		pserialize_read_exit(s);
574 
575 		return;
576 	}
577 }
578 
579 static void
580 fdt_device_register(device_t self, void *aux)
581 {
582 	const struct fdt_platform *plat = fdt_platform_find();
583 
584 	if (device_is_a(self, "armfdt")) {
585 		fdt_setup_initrd();
586 
587 #if NWSDISPLAY > 0 && NGENFB > 0
588 		/*
589 		 * Setup framebuffer console, if present.
590 		 */
591 		arm_simplefb_preattach();
592 #endif
593 	}
594 
595 #if NWSDISPLAY > 0 && NGENFB > 0
596 	if (device_is_a(self, "genfb")) {
597 		prop_dictionary_t dict = device_properties(self);
598 		prop_dictionary_set_uint64(dict,
599 		    "simplefb-physaddr", arm_simplefb_physaddr());
600 	}
601 #endif
602 
603 	if (plat && plat->fp_device_register)
604 		plat->fp_device_register(self, aux);
605 }
606 
607 static void
608 fdt_device_register_post_config(device_t self, void *aux)
609 {
610 #if NUKBD > 0 && NWSDISPLAY > 0
611 	if (device_is_a(self, "wsdisplay")) {
612 		struct wsdisplay_softc *sc = device_private(self);
613 		if (wsdisplay_isconsole(sc))
614 			ukbd_cnattach();
615 	}
616 #endif
617 }
618 
619 static void
620 fdt_cpu_rootconf(void)
621 {
622 	device_t dev;
623 	deviter_t di;
624 
625 	if (booted_device != NULL)
626 		return;
627 
628 	for (dev = deviter_first(&di, 0); dev; dev = deviter_next(&di)) {
629 		if (device_class(dev) != DV_DISK)
630 			continue;
631 
632 		fdt_detect_root_device(dev);
633 
634 		if (booted_device != NULL)
635 			break;
636 	}
637 	deviter_release(&di);
638 }
639 
640 static void
641 fdt_reset(void)
642 {
643 	const struct fdt_platform *plat = fdt_platform_find();
644 
645 	fdtbus_power_reset();
646 
647 	if (plat && plat->fp_reset)
648 		plat->fp_reset();
649 }
650 
651 static void
652 fdt_powerdown(void)
653 {
654 	fdtbus_power_poweroff();
655 }
656 
657 #if BYTE_ORDER == BIG_ENDIAN
658 static void
659 fdt_update_fb_format(void)
660 {
661 	int off, len;
662 	const char *format, *replace;
663 
664 	off = fdt_path_offset(fdt_data, "/chosen");
665 	if (off < 0)
666 		return;
667 
668 	for (;;) {
669 		off = fdt_node_offset_by_compatible(fdt_data, off,
670 		    "simple-framebuffer");
671 		if (off < 0)
672 			return;
673 
674 		format = fdt_getprop(fdt_data, off, "format", &len);
675 		if (format == NULL)
676 			continue;
677 
678 		replace = NULL;
679 		if (strcmp(format, "a8b8g8r8") == 0)
680 			replace = "r8g8b8a8";
681 		else if (strcmp(format, "x8r8g8b8") == 0)
682 			replace = "b8g8r8x8";
683 		if (replace != NULL)
684 			fdt_setprop(fdt_data, off, "format", replace,
685 			    strlen(replace) + 1);
686 	}
687 }
688 #endif
689