xref: /linux/arch/mips/kernel/setup.c (revision 23c996fc2bc1978a02c64eddb90b4ab5d309c8df)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 1995 Linus Torvalds
7  * Copyright (C) 1995 Waldorf Electronics
8  * Copyright (C) 1994, 95, 96, 97, 98, 99, 2000, 01, 02, 03  Ralf Baechle
9  * Copyright (C) 1996 Stoned Elipot
10  * Copyright (C) 1999 Silicon Graphics, Inc.
11  * Copyright (C) 2000, 2001, 2002, 2007	 Maciej W. Rozycki
12  */
13 #include <linux/init.h>
14 #include <linux/cpu.h>
15 #include <linux/delay.h>
16 #include <linux/ioport.h>
17 #include <linux/export.h>
18 #include <linux/memblock.h>
19 #include <linux/initrd.h>
20 #include <linux/root_dev.h>
21 #include <linux/highmem.h>
22 #include <linux/console.h>
23 #include <linux/pfn.h>
24 #include <linux/debugfs.h>
25 #include <linux/kexec.h>
26 #include <linux/sizes.h>
27 #include <linux/device.h>
28 #include <linux/dma-map-ops.h>
29 #include <linux/decompress/generic.h>
30 #include <linux/of_fdt.h>
31 #include <linux/dmi.h>
32 #include <linux/crash_dump.h>
33 
34 #include <asm/addrspace.h>
35 #include <asm/bootinfo.h>
36 #include <asm/bugs.h>
37 #include <asm/cache.h>
38 #include <asm/cdmm.h>
39 #include <asm/cpu.h>
40 #include <asm/debug.h>
41 #include <asm/mmzone.h>
42 #include <asm/sections.h>
43 #include <asm/setup.h>
44 #include <asm/smp-ops.h>
45 #include <asm/mips-cps.h>
46 #include <asm/prom.h>
47 #include <asm/fw/fw.h>
48 
49 #ifdef CONFIG_MIPS_ELF_APPENDED_DTB
50 char __section(".appended_dtb") __appended_dtb[0x100000];
51 #endif /* CONFIG_MIPS_ELF_APPENDED_DTB */
52 
53 struct cpuinfo_mips cpu_data[NR_CPUS] __read_mostly;
54 
55 EXPORT_SYMBOL(cpu_data);
56 
57 /*
58  * Setup information
59  *
60  * These are initialized so they are in the .data section
61  */
62 unsigned long mips_machtype __read_mostly = MACH_UNKNOWN;
63 
64 EXPORT_SYMBOL(mips_machtype);
65 
66 static char __initdata command_line[COMMAND_LINE_SIZE];
67 char __initdata arcs_cmdline[COMMAND_LINE_SIZE];
68 
69 #ifdef CONFIG_CMDLINE_BOOL
70 static const char builtin_cmdline[] __initconst = CONFIG_CMDLINE;
71 #else
72 static const char builtin_cmdline[] __initconst = "";
73 #endif
74 
75 /*
76  * mips_io_port_base is the begin of the address space to which x86 style
77  * I/O ports are mapped.
78  */
79 unsigned long mips_io_port_base = -1;
80 EXPORT_SYMBOL(mips_io_port_base);
81 
82 static struct resource code_resource = { .name = "Kernel code", };
83 static struct resource data_resource = { .name = "Kernel data", };
84 static struct resource bss_resource = { .name = "Kernel bss", };
85 
86 unsigned long __kaslr_offset __ro_after_init;
87 EXPORT_SYMBOL(__kaslr_offset);
88 
89 static void *detect_magic __initdata = detect_memory_region;
90 
91 #ifdef CONFIG_MIPS_AUTO_PFN_OFFSET
92 unsigned long ARCH_PFN_OFFSET;
93 EXPORT_SYMBOL(ARCH_PFN_OFFSET);
94 #endif
95 
96 void __init detect_memory_region(phys_addr_t start, phys_addr_t sz_min, phys_addr_t sz_max)
97 {
98 	void *dm = &detect_magic;
99 	phys_addr_t size;
100 
101 	for (size = sz_min; size < sz_max; size <<= 1) {
102 		if (!memcmp(dm, dm + size, sizeof(detect_magic)))
103 			break;
104 	}
105 
106 	pr_debug("Memory: %lluMB of RAM detected at 0x%llx (min: %lluMB, max: %lluMB)\n",
107 		((unsigned long long) size) / SZ_1M,
108 		(unsigned long long) start,
109 		((unsigned long long) sz_min) / SZ_1M,
110 		((unsigned long long) sz_max) / SZ_1M);
111 
112 	memblock_add(start, size);
113 }
114 
115 /*
116  * Manage initrd
117  */
118 #ifdef CONFIG_BLK_DEV_INITRD
119 
120 static int __init rd_start_early(char *p)
121 {
122 	unsigned long start = memparse(p, &p);
123 
124 #ifdef CONFIG_64BIT
125 	/* Guess if the sign extension was forgotten by bootloader */
126 	if (start < XKPHYS)
127 		start = (int)start;
128 #endif
129 	initrd_start = start;
130 	initrd_end += start;
131 	return 0;
132 }
133 early_param("rd_start", rd_start_early);
134 
135 static int __init rd_size_early(char *p)
136 {
137 	initrd_end += memparse(p, &p);
138 	return 0;
139 }
140 early_param("rd_size", rd_size_early);
141 
142 /* it returns the next free pfn after initrd */
143 static unsigned long __init init_initrd(void)
144 {
145 	unsigned long end;
146 
147 	/*
148 	 * Board specific code or command line parser should have
149 	 * already set up initrd_start and initrd_end. In these cases
150 	 * perform sanity checks and use them if all looks good.
151 	 */
152 	if (!initrd_start || initrd_end <= initrd_start)
153 		goto disable;
154 
155 	if (initrd_start & ~PAGE_MASK) {
156 		pr_err("initrd start must be page aligned\n");
157 		goto disable;
158 	}
159 
160 	/*
161 	 * Sanitize initrd addresses. For example firmware
162 	 * can't guess if they need to pass them through
163 	 * 64-bits values if the kernel has been built in pure
164 	 * 32-bit. We need also to switch from KSEG0 to XKPHYS
165 	 * addresses now, so the code can now safely use __pa().
166 	 */
167 	end = __pa(initrd_end);
168 	initrd_end = (unsigned long)__va(end);
169 	initrd_start = (unsigned long)__va(__pa(initrd_start));
170 
171 	if (initrd_start < PAGE_OFFSET) {
172 		pr_err("initrd start < PAGE_OFFSET\n");
173 		goto disable;
174 	}
175 
176 	ROOT_DEV = Root_RAM0;
177 	return PFN_UP(end);
178 disable:
179 	initrd_start = 0;
180 	initrd_end = 0;
181 	return 0;
182 }
183 
184 /* In some conditions (e.g. big endian bootloader with a little endian
185    kernel), the initrd might appear byte swapped.  Try to detect this and
186    byte swap it if needed.  */
187 static void __init maybe_bswap_initrd(void)
188 {
189 #if defined(CONFIG_CPU_CAVIUM_OCTEON)
190 	u64 buf;
191 
192 	/* Check for CPIO signature */
193 	if (!memcmp((void *)initrd_start, "070701", 6))
194 		return;
195 
196 	/* Check for compressed initrd */
197 	if (decompress_method((unsigned char *)initrd_start, 8, NULL))
198 		return;
199 
200 	/* Try again with a byte swapped header */
201 	buf = swab64p((u64 *)initrd_start);
202 	if (!memcmp(&buf, "070701", 6) ||
203 	    decompress_method((unsigned char *)(&buf), 8, NULL)) {
204 		unsigned long i;
205 
206 		pr_info("Byteswapped initrd detected\n");
207 		for (i = initrd_start; i < ALIGN(initrd_end, 8); i += 8)
208 			swab64s((u64 *)i);
209 	}
210 #endif
211 }
212 
213 static void __init finalize_initrd(void)
214 {
215 	unsigned long size = initrd_end - initrd_start;
216 
217 	if (size == 0) {
218 		printk(KERN_INFO "Initrd not found or empty");
219 		goto disable;
220 	}
221 	if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
222 		printk(KERN_ERR "Initrd extends beyond end of memory");
223 		goto disable;
224 	}
225 
226 	maybe_bswap_initrd();
227 
228 	memblock_reserve(__pa(initrd_start), size);
229 	initrd_below_start_ok = 1;
230 
231 	pr_info("Initial ramdisk at: 0x%lx (%lu bytes)\n",
232 		initrd_start, size);
233 	return;
234 disable:
235 	printk(KERN_CONT " - disabling initrd\n");
236 	initrd_start = 0;
237 	initrd_end = 0;
238 }
239 
240 #else  /* !CONFIG_BLK_DEV_INITRD */
241 
242 static unsigned long __init init_initrd(void)
243 {
244 	return 0;
245 }
246 
247 #define finalize_initrd()	do {} while (0)
248 
249 #endif
250 
251 /*
252  * Initialize the bootmem allocator. It also setup initrd related data
253  * if needed.
254  */
255 #if defined(CONFIG_SGI_IP27) || (defined(CONFIG_CPU_LOONGSON64) && defined(CONFIG_NUMA))
256 
257 static void __init bootmem_init(void)
258 {
259 	init_initrd();
260 	finalize_initrd();
261 }
262 
263 #else  /* !CONFIG_SGI_IP27 */
264 
265 static void __init bootmem_init(void)
266 {
267 	phys_addr_t ramstart, ramend;
268 	unsigned long start, end;
269 	int i;
270 
271 	ramstart = memblock_start_of_DRAM();
272 	ramend = memblock_end_of_DRAM();
273 
274 	/*
275 	 * Sanity check any INITRD first. We don't take it into account
276 	 * for bootmem setup initially, rely on the end-of-kernel-code
277 	 * as our memory range starting point. Once bootmem is inited we
278 	 * will reserve the area used for the initrd.
279 	 */
280 	init_initrd();
281 
282 	/* Reserve memory occupied by kernel. */
283 	memblock_reserve(__pa_symbol(&_text),
284 			__pa_symbol(&_end) - __pa_symbol(&_text));
285 
286 	/* max_low_pfn is not a number of pages but the end pfn of low mem */
287 
288 #ifdef CONFIG_MIPS_AUTO_PFN_OFFSET
289 	ARCH_PFN_OFFSET = PFN_UP(ramstart);
290 #else
291 	/*
292 	 * Reserve any memory between the start of RAM and PHYS_OFFSET
293 	 */
294 	if (ramstart > PHYS_OFFSET)
295 		memblock_reserve(PHYS_OFFSET, ramstart - PHYS_OFFSET);
296 
297 	if (PFN_UP(ramstart) > ARCH_PFN_OFFSET) {
298 		pr_info("Wasting %lu bytes for tracking %lu unused pages\n",
299 			(unsigned long)((PFN_UP(ramstart) - ARCH_PFN_OFFSET) * sizeof(struct page)),
300 			(unsigned long)(PFN_UP(ramstart) - ARCH_PFN_OFFSET));
301 	}
302 #endif
303 
304 	min_low_pfn = ARCH_PFN_OFFSET;
305 	max_pfn = PFN_DOWN(ramend);
306 	for_each_mem_pfn_range(i, MAX_NUMNODES, &start, &end, NULL) {
307 		/*
308 		 * Skip highmem here so we get an accurate max_low_pfn if low
309 		 * memory stops short of high memory.
310 		 * If the region overlaps HIGHMEM_START, end is clipped so
311 		 * max_pfn excludes the highmem portion.
312 		 */
313 		if (start >= PFN_DOWN(HIGHMEM_START))
314 			continue;
315 		if (end > PFN_DOWN(HIGHMEM_START))
316 			end = PFN_DOWN(HIGHMEM_START);
317 		if (end > max_low_pfn)
318 			max_low_pfn = end;
319 	}
320 
321 	if (min_low_pfn >= max_low_pfn)
322 		panic("Incorrect memory mapping !!!");
323 
324 	if (max_pfn > PFN_DOWN(HIGHMEM_START)) {
325 		max_low_pfn = PFN_DOWN(HIGHMEM_START);
326 #ifdef CONFIG_HIGHMEM
327 		highstart_pfn = max_low_pfn;
328 		highend_pfn = max_pfn;
329 #else
330 		max_pfn = max_low_pfn;
331 #endif
332 	}
333 
334 	/*
335 	 * Reserve initrd memory if needed.
336 	 */
337 	finalize_initrd();
338 }
339 
340 #endif	/* CONFIG_SGI_IP27 */
341 
342 static int usermem __initdata;
343 
344 static int __init early_parse_mem(char *p)
345 {
346 	phys_addr_t start, size;
347 
348 	if (!p) {
349 		pr_err("mem parameter is empty, do nothing\n");
350 		return -EINVAL;
351 	}
352 
353 	/*
354 	 * If a user specifies memory size, we
355 	 * blow away any automatically generated
356 	 * size.
357 	 */
358 	if (usermem == 0) {
359 		usermem = 1;
360 		memblock_remove(memblock_start_of_DRAM(),
361 			memblock_end_of_DRAM() - memblock_start_of_DRAM());
362 	}
363 	start = 0;
364 	size = memparse(p, &p);
365 	if (*p == '@')
366 		start = memparse(p + 1, &p);
367 
368 	if (IS_ENABLED(CONFIG_NUMA))
369 		memblock_add_node(start, size, pa_to_nid(start), MEMBLOCK_NONE);
370 	else
371 		memblock_add(start, size);
372 
373 	return 0;
374 }
375 early_param("mem", early_parse_mem);
376 
377 static int __init early_parse_memmap(char *p)
378 {
379 	char *oldp;
380 	u64 start_at, mem_size;
381 
382 	if (!p)
383 		return -EINVAL;
384 
385 	if (!strncmp(p, "exactmap", 8)) {
386 		pr_err("\"memmap=exactmap\" invalid on MIPS\n");
387 		return 0;
388 	}
389 
390 	oldp = p;
391 	mem_size = memparse(p, &p);
392 	if (p == oldp)
393 		return -EINVAL;
394 
395 	if (*p == '@') {
396 		start_at = memparse(p+1, &p);
397 		memblock_add(start_at, mem_size);
398 	} else if (*p == '#') {
399 		pr_err("\"memmap=nn#ss\" (force ACPI data) invalid on MIPS\n");
400 		return -EINVAL;
401 	} else if (*p == '$') {
402 		start_at = memparse(p+1, &p);
403 		memblock_add(start_at, mem_size);
404 		memblock_reserve(start_at, mem_size);
405 	} else {
406 		pr_err("\"memmap\" invalid format!\n");
407 		return -EINVAL;
408 	}
409 
410 	if (*p == '\0') {
411 		usermem = 1;
412 		return 0;
413 	} else
414 		return -EINVAL;
415 }
416 early_param("memmap", early_parse_memmap);
417 
418 static void __init mips_reserve_vmcore(void)
419 {
420 #ifdef CONFIG_PROC_VMCORE
421 	phys_addr_t start, end;
422 	u64 i;
423 
424 	if (!elfcorehdr_size) {
425 		for_each_mem_range(i, &start, &end) {
426 			if (elfcorehdr_addr >= start && elfcorehdr_addr < end) {
427 				/*
428 				 * Reserve from the elf core header to the end of
429 				 * the memory segment, that should all be kdump
430 				 * reserved memory.
431 				 */
432 				elfcorehdr_size = end - elfcorehdr_addr;
433 				break;
434 			}
435 		}
436 	}
437 
438 	pr_info("Reserving %ldKB of memory at %ldKB for kdump\n",
439 		(unsigned long)elfcorehdr_size >> 10, (unsigned long)elfcorehdr_addr >> 10);
440 
441 	memblock_reserve(elfcorehdr_addr, elfcorehdr_size);
442 #endif
443 }
444 
445 /* 64M alignment for crash kernel regions */
446 #define CRASH_ALIGN	SZ_64M
447 #define CRASH_ADDR_MAX	SZ_512M
448 
449 static void __init mips_parse_crashkernel(void)
450 {
451 	unsigned long long total_mem;
452 	unsigned long long crash_size, crash_base;
453 	int ret;
454 
455 	if (!IS_ENABLED(CONFIG_CRASH_RESERVE))
456 		return;
457 
458 	total_mem = memblock_phys_mem_size();
459 	ret = parse_crashkernel(boot_command_line, total_mem,
460 				&crash_size, &crash_base,
461 				NULL, NULL);
462 	if (ret != 0 || crash_size <= 0)
463 		return;
464 
465 	if (crash_base <= 0) {
466 		crash_base = memblock_phys_alloc_range(crash_size, CRASH_ALIGN,
467 						       CRASH_ALIGN,
468 						       CRASH_ADDR_MAX);
469 		if (!crash_base) {
470 			pr_warn("crashkernel reservation failed - No suitable area found.\n");
471 			return;
472 		}
473 	} else {
474 		unsigned long long start;
475 
476 		start = memblock_phys_alloc_range(crash_size, 1,
477 						  crash_base,
478 						  crash_base + crash_size);
479 		if (start != crash_base) {
480 			pr_warn("Invalid memory region reserved for crash kernel\n");
481 			return;
482 		}
483 	}
484 
485 	crashk_res.start = crash_base;
486 	crashk_res.end	 = crash_base + crash_size - 1;
487 }
488 
489 static void __init request_crashkernel(struct resource *res)
490 {
491 	int ret;
492 
493 	if (!IS_ENABLED(CONFIG_CRASH_RESERVE))
494 		return;
495 
496 	if (crashk_res.start == crashk_res.end)
497 		return;
498 
499 	ret = request_resource(res, &crashk_res);
500 	if (!ret)
501 		pr_info("Reserving %ldMB of memory at %ldMB for crashkernel\n",
502 			(unsigned long)(resource_size(&crashk_res) >> 20),
503 			(unsigned long)(crashk_res.start  >> 20));
504 }
505 
506 static void __init check_kernel_sections_mem(void)
507 {
508 	phys_addr_t start = __pa_symbol(&_text);
509 	phys_addr_t size = __pa_symbol(&_end) - start;
510 
511 	if (!memblock_is_region_memory(start, size)) {
512 		pr_info("Kernel sections are not in the memory maps\n");
513 		memblock_add(start, size);
514 	}
515 }
516 
517 static void __init bootcmdline_append(const char *s, size_t max)
518 {
519 	if (!s[0] || !max)
520 		return;
521 
522 	if (boot_command_line[0])
523 		strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
524 
525 	strlcat(boot_command_line, s, max);
526 }
527 
528 #ifdef CONFIG_OF_EARLY_FLATTREE
529 
530 static int __init bootcmdline_scan_chosen(unsigned long node, const char *uname,
531 					  int depth, void *data)
532 {
533 	bool *dt_bootargs = data;
534 	const char *p;
535 	int l;
536 
537 	if (depth != 1 || !data ||
538 	    (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
539 		return 0;
540 
541 	p = of_get_flat_dt_prop(node, "bootargs", &l);
542 	if (p != NULL && l > 0) {
543 		bootcmdline_append(p, min(l, COMMAND_LINE_SIZE));
544 		*dt_bootargs = true;
545 	}
546 
547 	return 1;
548 }
549 
550 #endif /* CONFIG_OF_EARLY_FLATTREE */
551 
552 static void __init bootcmdline_init(void)
553 {
554 	bool dt_bootargs = false;
555 
556 	/*
557 	 * If CMDLINE_OVERRIDE is enabled then initializing the command line is
558 	 * trivial - we simply use the built-in command line unconditionally &
559 	 * unmodified.
560 	 */
561 	if (IS_ENABLED(CONFIG_CMDLINE_OVERRIDE)) {
562 		strscpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
563 		return;
564 	}
565 
566 	/*
567 	 * If the user specified a built-in command line &
568 	 * MIPS_CMDLINE_BUILTIN_EXTEND, then the built-in command line is
569 	 * prepended to arguments from the bootloader or DT so we'll copy them
570 	 * to the start of boot_command_line here. Otherwise, empty
571 	 * boot_command_line to undo anything early_init_dt_scan_chosen() did.
572 	 */
573 	if (IS_ENABLED(CONFIG_MIPS_CMDLINE_BUILTIN_EXTEND))
574 		strscpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
575 	else
576 		boot_command_line[0] = 0;
577 
578 #ifdef CONFIG_OF_EARLY_FLATTREE
579 	/*
580 	 * If we're configured to take boot arguments from DT, look for those
581 	 * now.
582 	 */
583 	if (IS_ENABLED(CONFIG_MIPS_CMDLINE_FROM_DTB) ||
584 	    IS_ENABLED(CONFIG_MIPS_CMDLINE_DTB_EXTEND))
585 		of_scan_flat_dt(bootcmdline_scan_chosen, &dt_bootargs);
586 #endif
587 
588 	/*
589 	 * If we didn't get any arguments from DT (regardless of whether that's
590 	 * because we weren't configured to look for them, or because we looked
591 	 * & found none) then we'll take arguments from the bootloader.
592 	 * plat_mem_setup() should have filled arcs_cmdline with arguments from
593 	 * the bootloader.
594 	 */
595 	if (IS_ENABLED(CONFIG_MIPS_CMDLINE_DTB_EXTEND) || !dt_bootargs)
596 		bootcmdline_append(arcs_cmdline, COMMAND_LINE_SIZE);
597 
598 	/*
599 	 * If the user specified a built-in command line & we didn't already
600 	 * prepend it, we append it to boot_command_line here.
601 	 */
602 	if (IS_ENABLED(CONFIG_CMDLINE_BOOL) &&
603 	    !IS_ENABLED(CONFIG_MIPS_CMDLINE_BUILTIN_EXTEND))
604 		bootcmdline_append(builtin_cmdline, COMMAND_LINE_SIZE);
605 }
606 
607 /*
608  * arch_mem_init - initialize memory management subsystem
609  *
610  *  o plat_mem_setup() detects the memory configuration and will record detected
611  *    memory areas using memblock_add.
612  *
613  * At this stage the memory configuration of the system is known to the
614  * kernel but generic memory management system is still entirely uninitialized.
615  *
616  *  o bootmem_init()
617  *  o sparse_init()
618  *  o paging_init()
619  *  o dma_contiguous_reserve()
620  *
621  * At this stage the bootmem allocator is ready to use.
622  *
623  * NOTE: historically plat_mem_setup did the entire platform initialization.
624  *	 This was rather impractical because it meant plat_mem_setup had to
625  * get away without any kind of memory allocator.  To keep old code from
626  * breaking plat_setup was just renamed to plat_mem_setup and a second platform
627  * initialization hook for anything else was introduced.
628  */
629 static void __init arch_mem_init(char **cmdline_p)
630 {
631 	/* call board setup routine */
632 	plat_mem_setup();
633 	memblock_set_bottom_up(true);
634 
635 	bootcmdline_init();
636 	strscpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
637 	*cmdline_p = command_line;
638 
639 	parse_early_param();
640 
641 	if (usermem)
642 		pr_info("User-defined physical RAM map overwrite\n");
643 
644 	check_kernel_sections_mem();
645 
646 	early_init_fdt_reserve_self();
647 	early_init_fdt_scan_reserved_mem();
648 
649 #ifndef CONFIG_NUMA
650 	memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
651 #endif
652 	bootmem_init();
653 
654 	/*
655 	 * Prevent memblock from allocating high memory.
656 	 * This cannot be done before max_low_pfn is detected, so up
657 	 * to this point is possible to only reserve physical memory
658 	 * with memblock_reserve; memblock_alloc* can be used
659 	 * only after this point
660 	 */
661 	memblock_set_current_limit(PFN_PHYS(max_low_pfn));
662 
663 	mips_reserve_vmcore();
664 
665 	mips_parse_crashkernel();
666 	device_tree_init();
667 
668 	/*
669 	 * In order to reduce the possibility of kernel panic when failed to
670 	 * get IO TLB memory under CONFIG_SWIOTLB, it is better to allocate
671 	 * low memory as small as possible before plat_swiotlb_setup(), so
672 	 * make sparse_init() using top-down allocation.
673 	 */
674 	memblock_set_bottom_up(false);
675 	sparse_init();
676 	memblock_set_bottom_up(true);
677 
678 	plat_swiotlb_setup();
679 
680 	dma_contiguous_reserve(PFN_PHYS(max_low_pfn));
681 
682 	/* Reserve for hibernation. */
683 	memblock_reserve(__pa_symbol(&__nosave_begin),
684 		__pa_symbol(&__nosave_end) - __pa_symbol(&__nosave_begin));
685 
686 	early_memtest(PFN_PHYS(ARCH_PFN_OFFSET), PFN_PHYS(max_low_pfn));
687 }
688 
689 static void __init resource_init(void)
690 {
691 	phys_addr_t start, end;
692 	u64 i;
693 
694 	if (UNCAC_BASE != IO_BASE)
695 		return;
696 
697 	code_resource.start = __pa_symbol(&_text);
698 	code_resource.end = __pa_symbol(&_etext) - 1;
699 	data_resource.start = __pa_symbol(&_etext);
700 	data_resource.end = __pa_symbol(&_edata) - 1;
701 	bss_resource.start = __pa_symbol(&__bss_start);
702 	bss_resource.end = __pa_symbol(&__bss_stop) - 1;
703 
704 	for_each_mem_range(i, &start, &end) {
705 		struct resource *res;
706 
707 		res = memblock_alloc(sizeof(struct resource), SMP_CACHE_BYTES);
708 		if (!res)
709 			panic("%s: Failed to allocate %zu bytes\n", __func__,
710 			      sizeof(struct resource));
711 
712 		res->start = start;
713 		/*
714 		 * In memblock, end points to the first byte after the
715 		 * range while in resourses, end points to the last byte in
716 		 * the range.
717 		 */
718 		res->end = end - 1;
719 		res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
720 		res->name = "System RAM";
721 
722 		request_resource(&iomem_resource, res);
723 
724 		/*
725 		 *  We don't know which RAM region contains kernel data,
726 		 *  so we try it repeatedly and let the resource manager
727 		 *  test it.
728 		 */
729 		request_resource(res, &code_resource);
730 		request_resource(res, &data_resource);
731 		request_resource(res, &bss_resource);
732 		request_crashkernel(res);
733 	}
734 }
735 
736 #ifdef CONFIG_SMP
737 static void __init prefill_possible_map(void)
738 {
739 	int i, possible = num_possible_cpus();
740 
741 	if (possible > nr_cpu_ids)
742 		possible = nr_cpu_ids;
743 
744 	for (i = 0; i < possible; i++)
745 		set_cpu_possible(i, true);
746 	for (; i < NR_CPUS; i++)
747 		set_cpu_possible(i, false);
748 
749 	set_nr_cpu_ids(possible);
750 }
751 #else
752 static inline void prefill_possible_map(void) {}
753 #endif
754 
755 static void __init setup_rng_seed(void)
756 {
757 	char *rng_seed_hex = fw_getenv("rngseed");
758 	u8 rng_seed[512];
759 	size_t len;
760 
761 	if (!rng_seed_hex)
762 		return;
763 
764 	len = min(sizeof(rng_seed), strlen(rng_seed_hex) / 2);
765 	if (hex2bin(rng_seed, rng_seed_hex, len))
766 		return;
767 
768 	add_bootloader_randomness(rng_seed, len);
769 	memzero_explicit(rng_seed, len);
770 	memzero_explicit(rng_seed_hex, len * 2);
771 }
772 
773 void __init setup_arch(char **cmdline_p)
774 {
775 	cpu_probe();
776 	mips_cm_probe();
777 	prom_init();
778 
779 	setup_early_fdc_console();
780 #ifdef CONFIG_EARLY_PRINTK
781 	setup_early_printk();
782 #endif
783 	cpu_report();
784 	if (IS_ENABLED(CONFIG_CPU_R4X00_BUGS64))
785 		check_bugs64_early();
786 
787 	arch_mem_init(cmdline_p);
788 	dmi_setup();
789 
790 	resource_init();
791 	plat_smp_setup();
792 	prefill_possible_map();
793 
794 	cpu_cache_init();
795 	paging_init();
796 
797 	memblock_dump_all();
798 
799 	setup_rng_seed();
800 }
801 
802 unsigned long kernelsp[NR_CPUS];
803 unsigned long fw_arg0, fw_arg1, fw_arg2, fw_arg3;
804 
805 #ifdef CONFIG_DEBUG_FS
806 struct dentry *mips_debugfs_dir;
807 static int __init debugfs_mips(void)
808 {
809 	mips_debugfs_dir = debugfs_create_dir("mips", NULL);
810 	return 0;
811 }
812 arch_initcall(debugfs_mips);
813 #endif
814 
815 #ifdef CONFIG_DMA_NONCOHERENT
816 static int __init setcoherentio(char *str)
817 {
818 	dma_default_coherent = true;
819 	pr_info("Hardware DMA cache coherency (command line)\n");
820 	return 0;
821 }
822 early_param("coherentio", setcoherentio);
823 
824 static int __init setnocoherentio(char *str)
825 {
826 	dma_default_coherent = false;
827 	pr_info("Software DMA cache coherency (command line)\n");
828 	return 0;
829 }
830 early_param("nocoherentio", setnocoherentio);
831 #endif
832 
833 void __init arch_cpu_finalize_init(void)
834 {
835 	unsigned int cpu = smp_processor_id();
836 
837 	cpu_data[cpu].udelay_val = loops_per_jiffy;
838 	check_bugs32();
839 
840 	if (IS_ENABLED(CONFIG_CPU_R4X00_BUGS64))
841 		check_bugs64();
842 }
843