xref: /openbmc/linux/arch/mips/kernel/setup.c (revision 8dd99871)
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/ioport.h>
15 #include <linux/export.h>
16 #include <linux/screen_info.h>
17 #include <linux/memblock.h>
18 #include <linux/bootmem.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-contiguous.h>
29 #include <linux/decompress/generic.h>
30 #include <linux/of_fdt.h>
31 
32 #include <asm/addrspace.h>
33 #include <asm/bootinfo.h>
34 #include <asm/bugs.h>
35 #include <asm/cache.h>
36 #include <asm/cdmm.h>
37 #include <asm/cpu.h>
38 #include <asm/debug.h>
39 #include <asm/sections.h>
40 #include <asm/setup.h>
41 #include <asm/smp-ops.h>
42 #include <asm/prom.h>
43 
44 #ifdef CONFIG_MIPS_ELF_APPENDED_DTB
45 const char __section(.appended_dtb) __appended_dtb[0x100000];
46 #endif /* CONFIG_MIPS_ELF_APPENDED_DTB */
47 
48 struct cpuinfo_mips cpu_data[NR_CPUS] __read_mostly;
49 
50 EXPORT_SYMBOL(cpu_data);
51 
52 #ifdef CONFIG_VT
53 struct screen_info screen_info;
54 #endif
55 
56 /*
57  * Setup information
58  *
59  * These are initialized so they are in the .data section
60  */
61 unsigned long mips_machtype __read_mostly = MACH_UNKNOWN;
62 
63 EXPORT_SYMBOL(mips_machtype);
64 
65 struct boot_mem_map boot_mem_map;
66 
67 static char __initdata command_line[COMMAND_LINE_SIZE];
68 char __initdata arcs_cmdline[COMMAND_LINE_SIZE];
69 
70 #ifdef CONFIG_CMDLINE_BOOL
71 static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
72 #endif
73 
74 /*
75  * mips_io_port_base is the begin of the address space to which x86 style
76  * I/O ports are mapped.
77  */
78 const unsigned long mips_io_port_base = -1;
79 EXPORT_SYMBOL(mips_io_port_base);
80 
81 static struct resource code_resource = { .name = "Kernel code", };
82 static struct resource data_resource = { .name = "Kernel data", };
83 static struct resource bss_resource = { .name = "Kernel bss", };
84 
85 static void *detect_magic __initdata = detect_memory_region;
86 
87 void __init add_memory_region(phys_addr_t start, phys_addr_t size, long type)
88 {
89 	int x = boot_mem_map.nr_map;
90 	int i;
91 
92 	/*
93 	 * If the region reaches the top of the physical address space, adjust
94 	 * the size slightly so that (start + size) doesn't overflow
95 	 */
96 	if (start + size - 1 == PHYS_ADDR_MAX)
97 		--size;
98 
99 	/* Sanity check */
100 	if (start + size < start) {
101 		pr_warn("Trying to add an invalid memory region, skipped\n");
102 		return;
103 	}
104 
105 	/*
106 	 * Try to merge with existing entry, if any.
107 	 */
108 	for (i = 0; i < boot_mem_map.nr_map; i++) {
109 		struct boot_mem_map_entry *entry = boot_mem_map.map + i;
110 		unsigned long top;
111 
112 		if (entry->type != type)
113 			continue;
114 
115 		if (start + size < entry->addr)
116 			continue;			/* no overlap */
117 
118 		if (entry->addr + entry->size < start)
119 			continue;			/* no overlap */
120 
121 		top = max(entry->addr + entry->size, start + size);
122 		entry->addr = min(entry->addr, start);
123 		entry->size = top - entry->addr;
124 
125 		return;
126 	}
127 
128 	if (boot_mem_map.nr_map == BOOT_MEM_MAP_MAX) {
129 		pr_err("Ooops! Too many entries in the memory map!\n");
130 		return;
131 	}
132 
133 	boot_mem_map.map[x].addr = start;
134 	boot_mem_map.map[x].size = size;
135 	boot_mem_map.map[x].type = type;
136 	boot_mem_map.nr_map++;
137 }
138 
139 void __init detect_memory_region(phys_addr_t start, phys_addr_t sz_min, phys_addr_t sz_max)
140 {
141 	void *dm = &detect_magic;
142 	phys_addr_t size;
143 
144 	for (size = sz_min; size < sz_max; size <<= 1) {
145 		if (!memcmp(dm, dm + size, sizeof(detect_magic)))
146 			break;
147 	}
148 
149 	pr_debug("Memory: %lluMB of RAM detected at 0x%llx (min: %lluMB, max: %lluMB)\n",
150 		((unsigned long long) size) / SZ_1M,
151 		(unsigned long long) start,
152 		((unsigned long long) sz_min) / SZ_1M,
153 		((unsigned long long) sz_max) / SZ_1M);
154 
155 	add_memory_region(start, size, BOOT_MEM_RAM);
156 }
157 
158 static bool __init __maybe_unused memory_region_available(phys_addr_t start,
159 							  phys_addr_t size)
160 {
161 	int i;
162 	bool in_ram = false, free = true;
163 
164 	for (i = 0; i < boot_mem_map.nr_map; i++) {
165 		phys_addr_t start_, end_;
166 
167 		start_ = boot_mem_map.map[i].addr;
168 		end_ = boot_mem_map.map[i].addr + boot_mem_map.map[i].size;
169 
170 		switch (boot_mem_map.map[i].type) {
171 		case BOOT_MEM_RAM:
172 			if (start >= start_ && start + size <= end_)
173 				in_ram = true;
174 			break;
175 		case BOOT_MEM_RESERVED:
176 			if ((start >= start_ && start < end_) ||
177 			    (start < start_ && start + size >= start_))
178 				free = false;
179 			break;
180 		default:
181 			continue;
182 		}
183 	}
184 
185 	return in_ram && free;
186 }
187 
188 static void __init print_memory_map(void)
189 {
190 	int i;
191 	const int field = 2 * sizeof(unsigned long);
192 
193 	for (i = 0; i < boot_mem_map.nr_map; i++) {
194 		printk(KERN_INFO " memory: %0*Lx @ %0*Lx ",
195 		       field, (unsigned long long) boot_mem_map.map[i].size,
196 		       field, (unsigned long long) boot_mem_map.map[i].addr);
197 
198 		switch (boot_mem_map.map[i].type) {
199 		case BOOT_MEM_RAM:
200 			printk(KERN_CONT "(usable)\n");
201 			break;
202 		case BOOT_MEM_INIT_RAM:
203 			printk(KERN_CONT "(usable after init)\n");
204 			break;
205 		case BOOT_MEM_ROM_DATA:
206 			printk(KERN_CONT "(ROM data)\n");
207 			break;
208 		case BOOT_MEM_RESERVED:
209 			printk(KERN_CONT "(reserved)\n");
210 			break;
211 		default:
212 			printk(KERN_CONT "type %lu\n", boot_mem_map.map[i].type);
213 			break;
214 		}
215 	}
216 }
217 
218 /*
219  * Manage initrd
220  */
221 #ifdef CONFIG_BLK_DEV_INITRD
222 
223 static int __init rd_start_early(char *p)
224 {
225 	unsigned long start = memparse(p, &p);
226 
227 #ifdef CONFIG_64BIT
228 	/* Guess if the sign extension was forgotten by bootloader */
229 	if (start < XKPHYS)
230 		start = (int)start;
231 #endif
232 	initrd_start = start;
233 	initrd_end += start;
234 	return 0;
235 }
236 early_param("rd_start", rd_start_early);
237 
238 static int __init rd_size_early(char *p)
239 {
240 	initrd_end += memparse(p, &p);
241 	return 0;
242 }
243 early_param("rd_size", rd_size_early);
244 
245 /* it returns the next free pfn after initrd */
246 static unsigned long __init init_initrd(void)
247 {
248 	unsigned long end;
249 
250 	/*
251 	 * Board specific code or command line parser should have
252 	 * already set up initrd_start and initrd_end. In these cases
253 	 * perfom sanity checks and use them if all looks good.
254 	 */
255 	if (!initrd_start || initrd_end <= initrd_start)
256 		goto disable;
257 
258 	if (initrd_start & ~PAGE_MASK) {
259 		pr_err("initrd start must be page aligned\n");
260 		goto disable;
261 	}
262 	if (initrd_start < PAGE_OFFSET) {
263 		pr_err("initrd start < PAGE_OFFSET\n");
264 		goto disable;
265 	}
266 
267 	/*
268 	 * Sanitize initrd addresses. For example firmware
269 	 * can't guess if they need to pass them through
270 	 * 64-bits values if the kernel has been built in pure
271 	 * 32-bit. We need also to switch from KSEG0 to XKPHYS
272 	 * addresses now, so the code can now safely use __pa().
273 	 */
274 	end = __pa(initrd_end);
275 	initrd_end = (unsigned long)__va(end);
276 	initrd_start = (unsigned long)__va(__pa(initrd_start));
277 
278 	ROOT_DEV = Root_RAM0;
279 	return PFN_UP(end);
280 disable:
281 	initrd_start = 0;
282 	initrd_end = 0;
283 	return 0;
284 }
285 
286 /* In some conditions (e.g. big endian bootloader with a little endian
287    kernel), the initrd might appear byte swapped.  Try to detect this and
288    byte swap it if needed.  */
289 static void __init maybe_bswap_initrd(void)
290 {
291 #if defined(CONFIG_CPU_CAVIUM_OCTEON)
292 	u64 buf;
293 
294 	/* Check for CPIO signature */
295 	if (!memcmp((void *)initrd_start, "070701", 6))
296 		return;
297 
298 	/* Check for compressed initrd */
299 	if (decompress_method((unsigned char *)initrd_start, 8, NULL))
300 		return;
301 
302 	/* Try again with a byte swapped header */
303 	buf = swab64p((u64 *)initrd_start);
304 	if (!memcmp(&buf, "070701", 6) ||
305 	    decompress_method((unsigned char *)(&buf), 8, NULL)) {
306 		unsigned long i;
307 
308 		pr_info("Byteswapped initrd detected\n");
309 		for (i = initrd_start; i < ALIGN(initrd_end, 8); i += 8)
310 			swab64s((u64 *)i);
311 	}
312 #endif
313 }
314 
315 static void __init finalize_initrd(void)
316 {
317 	unsigned long size = initrd_end - initrd_start;
318 
319 	if (size == 0) {
320 		printk(KERN_INFO "Initrd not found or empty");
321 		goto disable;
322 	}
323 	if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
324 		printk(KERN_ERR "Initrd extends beyond end of memory");
325 		goto disable;
326 	}
327 
328 	maybe_bswap_initrd();
329 
330 	reserve_bootmem(__pa(initrd_start), size, BOOTMEM_DEFAULT);
331 	initrd_below_start_ok = 1;
332 
333 	pr_info("Initial ramdisk at: 0x%lx (%lu bytes)\n",
334 		initrd_start, size);
335 	return;
336 disable:
337 	printk(KERN_CONT " - disabling initrd\n");
338 	initrd_start = 0;
339 	initrd_end = 0;
340 }
341 
342 #else  /* !CONFIG_BLK_DEV_INITRD */
343 
344 static unsigned long __init init_initrd(void)
345 {
346 	return 0;
347 }
348 
349 #define finalize_initrd()	do {} while (0)
350 
351 #endif
352 
353 /*
354  * Initialize the bootmem allocator. It also setup initrd related data
355  * if needed.
356  */
357 #if defined(CONFIG_SGI_IP27) || (defined(CONFIG_CPU_LOONGSON3) && defined(CONFIG_NUMA))
358 
359 static void __init bootmem_init(void)
360 {
361 	init_initrd();
362 	finalize_initrd();
363 }
364 
365 #else  /* !CONFIG_SGI_IP27 */
366 
367 static unsigned long __init bootmap_bytes(unsigned long pages)
368 {
369 	unsigned long bytes = DIV_ROUND_UP(pages, 8);
370 
371 	return ALIGN(bytes, sizeof(long));
372 }
373 
374 static void __init bootmem_init(void)
375 {
376 	unsigned long reserved_end;
377 	unsigned long mapstart = ~0UL;
378 	unsigned long bootmap_size;
379 	phys_addr_t ramstart = PHYS_ADDR_MAX;
380 	bool bootmap_valid = false;
381 	int i;
382 
383 	/*
384 	 * Sanity check any INITRD first. We don't take it into account
385 	 * for bootmem setup initially, rely on the end-of-kernel-code
386 	 * as our memory range starting point. Once bootmem is inited we
387 	 * will reserve the area used for the initrd.
388 	 */
389 	init_initrd();
390 	reserved_end = (unsigned long) PFN_UP(__pa_symbol(&_end));
391 
392 	/*
393 	 * max_low_pfn is not a number of pages. The number of pages
394 	 * of the system is given by 'max_low_pfn - min_low_pfn'.
395 	 */
396 	min_low_pfn = ~0UL;
397 	max_low_pfn = 0;
398 
399 	/*
400 	 * Find the highest page frame number we have available
401 	 * and the lowest used RAM address
402 	 */
403 	for (i = 0; i < boot_mem_map.nr_map; i++) {
404 		unsigned long start, end;
405 
406 		if (boot_mem_map.map[i].type != BOOT_MEM_RAM)
407 			continue;
408 
409 		start = PFN_UP(boot_mem_map.map[i].addr);
410 		end = PFN_DOWN(boot_mem_map.map[i].addr
411 				+ boot_mem_map.map[i].size);
412 
413 		ramstart = min(ramstart, boot_mem_map.map[i].addr);
414 
415 #ifndef CONFIG_HIGHMEM
416 		/*
417 		 * Skip highmem here so we get an accurate max_low_pfn if low
418 		 * memory stops short of high memory.
419 		 * If the region overlaps HIGHMEM_START, end is clipped so
420 		 * max_pfn excludes the highmem portion.
421 		 */
422 		if (start >= PFN_DOWN(HIGHMEM_START))
423 			continue;
424 		if (end > PFN_DOWN(HIGHMEM_START))
425 			end = PFN_DOWN(HIGHMEM_START);
426 #endif
427 
428 		if (end > max_low_pfn)
429 			max_low_pfn = end;
430 		if (start < min_low_pfn)
431 			min_low_pfn = start;
432 		if (end <= reserved_end)
433 			continue;
434 #ifdef CONFIG_BLK_DEV_INITRD
435 		/* Skip zones before initrd and initrd itself */
436 		if (initrd_end && end <= (unsigned long)PFN_UP(__pa(initrd_end)))
437 			continue;
438 #endif
439 		if (start >= mapstart)
440 			continue;
441 		mapstart = max(reserved_end, start);
442 	}
443 
444 	/*
445 	 * Reserve any memory between the start of RAM and PHYS_OFFSET
446 	 */
447 	if (ramstart > PHYS_OFFSET)
448 		add_memory_region(PHYS_OFFSET, ramstart - PHYS_OFFSET,
449 				  BOOT_MEM_RESERVED);
450 
451 	if (min_low_pfn >= max_low_pfn)
452 		panic("Incorrect memory mapping !!!");
453 	if (min_low_pfn > ARCH_PFN_OFFSET) {
454 		pr_info("Wasting %lu bytes for tracking %lu unused pages\n",
455 			(min_low_pfn - ARCH_PFN_OFFSET) * sizeof(struct page),
456 			min_low_pfn - ARCH_PFN_OFFSET);
457 	} else if (ARCH_PFN_OFFSET - min_low_pfn > 0UL) {
458 		pr_info("%lu free pages won't be used\n",
459 			ARCH_PFN_OFFSET - min_low_pfn);
460 	}
461 	min_low_pfn = ARCH_PFN_OFFSET;
462 
463 	/*
464 	 * Determine low and high memory ranges
465 	 */
466 	max_pfn = max_low_pfn;
467 	if (max_low_pfn > PFN_DOWN(HIGHMEM_START)) {
468 #ifdef CONFIG_HIGHMEM
469 		highstart_pfn = PFN_DOWN(HIGHMEM_START);
470 		highend_pfn = max_low_pfn;
471 #endif
472 		max_low_pfn = PFN_DOWN(HIGHMEM_START);
473 	}
474 
475 #ifdef CONFIG_BLK_DEV_INITRD
476 	/*
477 	 * mapstart should be after initrd_end
478 	 */
479 	if (initrd_end)
480 		mapstart = max(mapstart, (unsigned long)PFN_UP(__pa(initrd_end)));
481 #endif
482 
483 	/*
484 	 * check that mapstart doesn't overlap with any of
485 	 * memory regions that have been reserved through eg. DTB
486 	 */
487 	bootmap_size = bootmap_bytes(max_low_pfn - min_low_pfn);
488 
489 	bootmap_valid = memory_region_available(PFN_PHYS(mapstart),
490 						bootmap_size);
491 	for (i = 0; i < boot_mem_map.nr_map && !bootmap_valid; i++) {
492 		unsigned long mapstart_addr;
493 
494 		switch (boot_mem_map.map[i].type) {
495 		case BOOT_MEM_RESERVED:
496 			mapstart_addr = PFN_ALIGN(boot_mem_map.map[i].addr +
497 						boot_mem_map.map[i].size);
498 			if (PHYS_PFN(mapstart_addr) < mapstart)
499 				break;
500 
501 			bootmap_valid = memory_region_available(mapstart_addr,
502 								bootmap_size);
503 			if (bootmap_valid)
504 				mapstart = PHYS_PFN(mapstart_addr);
505 			break;
506 		default:
507 			break;
508 		}
509 	}
510 
511 	if (!bootmap_valid)
512 		panic("No memory area to place a bootmap bitmap");
513 
514 	/*
515 	 * Initialize the boot-time allocator with low memory only.
516 	 */
517 	if (bootmap_size != init_bootmem_node(NODE_DATA(0), mapstart,
518 					 min_low_pfn, max_low_pfn))
519 		panic("Unexpected memory size required for bootmap");
520 
521 	for (i = 0; i < boot_mem_map.nr_map; i++) {
522 		unsigned long start, end;
523 
524 		start = PFN_UP(boot_mem_map.map[i].addr);
525 		end = PFN_DOWN(boot_mem_map.map[i].addr
526 				+ boot_mem_map.map[i].size);
527 
528 		if (start <= min_low_pfn)
529 			start = min_low_pfn;
530 		if (start >= end)
531 			continue;
532 
533 #ifndef CONFIG_HIGHMEM
534 		if (end > max_low_pfn)
535 			end = max_low_pfn;
536 
537 		/*
538 		 * ... finally, is the area going away?
539 		 */
540 		if (end <= start)
541 			continue;
542 #endif
543 
544 		memblock_add_node(PFN_PHYS(start), PFN_PHYS(end - start), 0);
545 	}
546 
547 	/*
548 	 * Register fully available low RAM pages with the bootmem allocator.
549 	 */
550 	for (i = 0; i < boot_mem_map.nr_map; i++) {
551 		unsigned long start, end, size;
552 
553 		start = PFN_UP(boot_mem_map.map[i].addr);
554 		end   = PFN_DOWN(boot_mem_map.map[i].addr
555 				    + boot_mem_map.map[i].size);
556 
557 		/*
558 		 * Reserve usable memory.
559 		 */
560 		switch (boot_mem_map.map[i].type) {
561 		case BOOT_MEM_RAM:
562 			break;
563 		case BOOT_MEM_INIT_RAM:
564 			memory_present(0, start, end);
565 			continue;
566 		default:
567 			/* Not usable memory */
568 			if (start > min_low_pfn && end < max_low_pfn)
569 				reserve_bootmem(boot_mem_map.map[i].addr,
570 						boot_mem_map.map[i].size,
571 						BOOTMEM_DEFAULT);
572 			continue;
573 		}
574 
575 		/*
576 		 * We are rounding up the start address of usable memory
577 		 * and at the end of the usable range downwards.
578 		 */
579 		if (start >= max_low_pfn)
580 			continue;
581 		if (start < reserved_end)
582 			start = reserved_end;
583 		if (end > max_low_pfn)
584 			end = max_low_pfn;
585 
586 		/*
587 		 * ... finally, is the area going away?
588 		 */
589 		if (end <= start)
590 			continue;
591 		size = end - start;
592 
593 		/* Register lowmem ranges */
594 		free_bootmem(PFN_PHYS(start), size << PAGE_SHIFT);
595 		memory_present(0, start, end);
596 	}
597 
598 	/*
599 	 * Reserve the bootmap memory.
600 	 */
601 	reserve_bootmem(PFN_PHYS(mapstart), bootmap_size, BOOTMEM_DEFAULT);
602 
603 #ifdef CONFIG_RELOCATABLE
604 	/*
605 	 * The kernel reserves all memory below its _end symbol as bootmem,
606 	 * but the kernel may now be at a much higher address. The memory
607 	 * between the original and new locations may be returned to the system.
608 	 */
609 	if (__pa_symbol(_text) > __pa_symbol(VMLINUX_LOAD_ADDRESS)) {
610 		unsigned long offset;
611 		extern void show_kernel_relocation(const char *level);
612 
613 		offset = __pa_symbol(_text) - __pa_symbol(VMLINUX_LOAD_ADDRESS);
614 		free_bootmem(__pa_symbol(VMLINUX_LOAD_ADDRESS), offset);
615 
616 #if defined(CONFIG_DEBUG_KERNEL) && defined(CONFIG_DEBUG_INFO)
617 		/*
618 		 * This information is necessary when debugging the kernel
619 		 * But is a security vulnerability otherwise!
620 		 */
621 		show_kernel_relocation(KERN_INFO);
622 #endif
623 	}
624 #endif
625 
626 	/*
627 	 * Reserve initrd memory if needed.
628 	 */
629 	finalize_initrd();
630 }
631 
632 #endif	/* CONFIG_SGI_IP27 */
633 
634 /*
635  * arch_mem_init - initialize memory management subsystem
636  *
637  *  o plat_mem_setup() detects the memory configuration and will record detected
638  *    memory areas using add_memory_region.
639  *
640  * At this stage the memory configuration of the system is known to the
641  * kernel but generic memory management system is still entirely uninitialized.
642  *
643  *  o bootmem_init()
644  *  o sparse_init()
645  *  o paging_init()
646  *  o dma_contiguous_reserve()
647  *
648  * At this stage the bootmem allocator is ready to use.
649  *
650  * NOTE: historically plat_mem_setup did the entire platform initialization.
651  *	 This was rather impractical because it meant plat_mem_setup had to
652  * get away without any kind of memory allocator.  To keep old code from
653  * breaking plat_setup was just renamed to plat_mem_setup and a second platform
654  * initialization hook for anything else was introduced.
655  */
656 
657 static int usermem __initdata;
658 
659 static int __init early_parse_mem(char *p)
660 {
661 	phys_addr_t start, size;
662 
663 	/*
664 	 * If a user specifies memory size, we
665 	 * blow away any automatically generated
666 	 * size.
667 	 */
668 	if (usermem == 0) {
669 		boot_mem_map.nr_map = 0;
670 		usermem = 1;
671 	}
672 	start = 0;
673 	size = memparse(p, &p);
674 	if (*p == '@')
675 		start = memparse(p + 1, &p);
676 
677 	add_memory_region(start, size, BOOT_MEM_RAM);
678 
679 	return 0;
680 }
681 early_param("mem", early_parse_mem);
682 
683 static int __init early_parse_memmap(char *p)
684 {
685 	char *oldp;
686 	u64 start_at, mem_size;
687 
688 	if (!p)
689 		return -EINVAL;
690 
691 	if (!strncmp(p, "exactmap", 8)) {
692 		pr_err("\"memmap=exactmap\" invalid on MIPS\n");
693 		return 0;
694 	}
695 
696 	oldp = p;
697 	mem_size = memparse(p, &p);
698 	if (p == oldp)
699 		return -EINVAL;
700 
701 	if (*p == '@') {
702 		start_at = memparse(p+1, &p);
703 		add_memory_region(start_at, mem_size, BOOT_MEM_RAM);
704 	} else if (*p == '#') {
705 		pr_err("\"memmap=nn#ss\" (force ACPI data) invalid on MIPS\n");
706 		return -EINVAL;
707 	} else if (*p == '$') {
708 		start_at = memparse(p+1, &p);
709 		add_memory_region(start_at, mem_size, BOOT_MEM_RESERVED);
710 	} else {
711 		pr_err("\"memmap\" invalid format!\n");
712 		return -EINVAL;
713 	}
714 
715 	if (*p == '\0') {
716 		usermem = 1;
717 		return 0;
718 	} else
719 		return -EINVAL;
720 }
721 early_param("memmap", early_parse_memmap);
722 
723 #ifdef CONFIG_PROC_VMCORE
724 unsigned long setup_elfcorehdr, setup_elfcorehdr_size;
725 static int __init early_parse_elfcorehdr(char *p)
726 {
727 	int i;
728 
729 	setup_elfcorehdr = memparse(p, &p);
730 
731 	for (i = 0; i < boot_mem_map.nr_map; i++) {
732 		unsigned long start = boot_mem_map.map[i].addr;
733 		unsigned long end = (boot_mem_map.map[i].addr +
734 				     boot_mem_map.map[i].size);
735 		if (setup_elfcorehdr >= start && setup_elfcorehdr < end) {
736 			/*
737 			 * Reserve from the elf core header to the end of
738 			 * the memory segment, that should all be kdump
739 			 * reserved memory.
740 			 */
741 			setup_elfcorehdr_size = end - setup_elfcorehdr;
742 			break;
743 		}
744 	}
745 	/*
746 	 * If we don't find it in the memory map, then we shouldn't
747 	 * have to worry about it, as the new kernel won't use it.
748 	 */
749 	return 0;
750 }
751 early_param("elfcorehdr", early_parse_elfcorehdr);
752 #endif
753 
754 static void __init arch_mem_addpart(phys_addr_t mem, phys_addr_t end, int type)
755 {
756 	phys_addr_t size;
757 	int i;
758 
759 	size = end - mem;
760 	if (!size)
761 		return;
762 
763 	/* Make sure it is in the boot_mem_map */
764 	for (i = 0; i < boot_mem_map.nr_map; i++) {
765 		if (mem >= boot_mem_map.map[i].addr &&
766 		    mem < (boot_mem_map.map[i].addr +
767 			   boot_mem_map.map[i].size))
768 			return;
769 	}
770 	add_memory_region(mem, size, type);
771 }
772 
773 #ifdef CONFIG_KEXEC
774 static inline unsigned long long get_total_mem(void)
775 {
776 	unsigned long long total;
777 
778 	total = max_pfn - min_low_pfn;
779 	return total << PAGE_SHIFT;
780 }
781 
782 static void __init mips_parse_crashkernel(void)
783 {
784 	unsigned long long total_mem;
785 	unsigned long long crash_size, crash_base;
786 	int ret;
787 
788 	total_mem = get_total_mem();
789 	ret = parse_crashkernel(boot_command_line, total_mem,
790 				&crash_size, &crash_base);
791 	if (ret != 0 || crash_size <= 0)
792 		return;
793 
794 	if (!memory_region_available(crash_base, crash_size)) {
795 		pr_warn("Invalid memory region reserved for crash kernel\n");
796 		return;
797 	}
798 
799 	crashk_res.start = crash_base;
800 	crashk_res.end	 = crash_base + crash_size - 1;
801 }
802 
803 static void __init request_crashkernel(struct resource *res)
804 {
805 	int ret;
806 
807 	if (crashk_res.start == crashk_res.end)
808 		return;
809 
810 	ret = request_resource(res, &crashk_res);
811 	if (!ret)
812 		pr_info("Reserving %ldMB of memory at %ldMB for crashkernel\n",
813 			(unsigned long)((crashk_res.end -
814 					 crashk_res.start + 1) >> 20),
815 			(unsigned long)(crashk_res.start  >> 20));
816 }
817 #else /* !defined(CONFIG_KEXEC)		*/
818 static void __init mips_parse_crashkernel(void)
819 {
820 }
821 
822 static void __init request_crashkernel(struct resource *res)
823 {
824 }
825 #endif /* !defined(CONFIG_KEXEC)  */
826 
827 #define USE_PROM_CMDLINE	IS_ENABLED(CONFIG_MIPS_CMDLINE_FROM_BOOTLOADER)
828 #define USE_DTB_CMDLINE		IS_ENABLED(CONFIG_MIPS_CMDLINE_FROM_DTB)
829 #define EXTEND_WITH_PROM	IS_ENABLED(CONFIG_MIPS_CMDLINE_DTB_EXTEND)
830 #define BUILTIN_EXTEND_WITH_PROM	\
831 	IS_ENABLED(CONFIG_MIPS_CMDLINE_BUILTIN_EXTEND)
832 
833 static void __init arch_mem_init(char **cmdline_p)
834 {
835 	struct memblock_region *reg;
836 	extern void plat_mem_setup(void);
837 
838 #if defined(CONFIG_CMDLINE_BOOL) && defined(CONFIG_CMDLINE_OVERRIDE)
839 	strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
840 #else
841 	if ((USE_PROM_CMDLINE && arcs_cmdline[0]) ||
842 	    (USE_DTB_CMDLINE && !boot_command_line[0]))
843 		strlcpy(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);
844 
845 	if (EXTEND_WITH_PROM && arcs_cmdline[0]) {
846 		if (boot_command_line[0])
847 			strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
848 		strlcat(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);
849 	}
850 
851 #if defined(CONFIG_CMDLINE_BOOL)
852 	if (builtin_cmdline[0]) {
853 		if (boot_command_line[0])
854 			strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
855 		strlcat(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
856 	}
857 
858 	if (BUILTIN_EXTEND_WITH_PROM && arcs_cmdline[0]) {
859 		if (boot_command_line[0])
860 			strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
861 		strlcat(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);
862 	}
863 #endif
864 #endif
865 
866 	/* call board setup routine */
867 	plat_mem_setup();
868 
869 	/*
870 	 * Make sure all kernel memory is in the maps.  The "UP" and
871 	 * "DOWN" are opposite for initdata since if it crosses over
872 	 * into another memory section you don't want that to be
873 	 * freed when the initdata is freed.
874 	 */
875 	arch_mem_addpart(PFN_DOWN(__pa_symbol(&_text)) << PAGE_SHIFT,
876 			 PFN_UP(__pa_symbol(&_edata)) << PAGE_SHIFT,
877 			 BOOT_MEM_RAM);
878 	arch_mem_addpart(PFN_UP(__pa_symbol(&__init_begin)) << PAGE_SHIFT,
879 			 PFN_DOWN(__pa_symbol(&__init_end)) << PAGE_SHIFT,
880 			 BOOT_MEM_INIT_RAM);
881 
882 	pr_info("Determined physical RAM map:\n");
883 	print_memory_map();
884 
885 	strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
886 
887 	*cmdline_p = command_line;
888 
889 	parse_early_param();
890 
891 	if (usermem) {
892 		pr_info("User-defined physical RAM map:\n");
893 		print_memory_map();
894 	}
895 
896 	early_init_fdt_reserve_self();
897 	early_init_fdt_scan_reserved_mem();
898 
899 	bootmem_init();
900 #ifdef CONFIG_PROC_VMCORE
901 	if (setup_elfcorehdr && setup_elfcorehdr_size) {
902 		printk(KERN_INFO "kdump reserved memory at %lx-%lx\n",
903 		       setup_elfcorehdr, setup_elfcorehdr_size);
904 		reserve_bootmem(setup_elfcorehdr, setup_elfcorehdr_size,
905 				BOOTMEM_DEFAULT);
906 	}
907 #endif
908 
909 	mips_parse_crashkernel();
910 #ifdef CONFIG_KEXEC
911 	if (crashk_res.start != crashk_res.end)
912 		reserve_bootmem(crashk_res.start,
913 				crashk_res.end - crashk_res.start + 1,
914 				BOOTMEM_DEFAULT);
915 #endif
916 	device_tree_init();
917 	sparse_init();
918 	plat_swiotlb_setup();
919 
920 	dma_contiguous_reserve(PFN_PHYS(max_low_pfn));
921 	/* Tell bootmem about cma reserved memblock section */
922 	for_each_memblock(reserved, reg)
923 		if (reg->size != 0)
924 			reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT);
925 
926 	reserve_bootmem_region(__pa_symbol(&__nosave_begin),
927 			__pa_symbol(&__nosave_end)); /* Reserve for hibernation */
928 }
929 
930 static void __init resource_init(void)
931 {
932 	int i;
933 
934 	if (UNCAC_BASE != IO_BASE)
935 		return;
936 
937 	code_resource.start = __pa_symbol(&_text);
938 	code_resource.end = __pa_symbol(&_etext) - 1;
939 	data_resource.start = __pa_symbol(&_etext);
940 	data_resource.end = __pa_symbol(&_edata) - 1;
941 	bss_resource.start = __pa_symbol(&__bss_start);
942 	bss_resource.end = __pa_symbol(&__bss_stop) - 1;
943 
944 	for (i = 0; i < boot_mem_map.nr_map; i++) {
945 		struct resource *res;
946 		unsigned long start, end;
947 
948 		start = boot_mem_map.map[i].addr;
949 		end = boot_mem_map.map[i].addr + boot_mem_map.map[i].size - 1;
950 		if (start >= HIGHMEM_START)
951 			continue;
952 		if (end >= HIGHMEM_START)
953 			end = HIGHMEM_START - 1;
954 
955 		res = alloc_bootmem(sizeof(struct resource));
956 
957 		res->start = start;
958 		res->end = end;
959 		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
960 
961 		switch (boot_mem_map.map[i].type) {
962 		case BOOT_MEM_RAM:
963 		case BOOT_MEM_INIT_RAM:
964 		case BOOT_MEM_ROM_DATA:
965 			res->name = "System RAM";
966 			res->flags |= IORESOURCE_SYSRAM;
967 			break;
968 		case BOOT_MEM_RESERVED:
969 		default:
970 			res->name = "reserved";
971 		}
972 
973 		request_resource(&iomem_resource, res);
974 
975 		/*
976 		 *  We don't know which RAM region contains kernel data,
977 		 *  so we try it repeatedly and let the resource manager
978 		 *  test it.
979 		 */
980 		request_resource(res, &code_resource);
981 		request_resource(res, &data_resource);
982 		request_resource(res, &bss_resource);
983 		request_crashkernel(res);
984 	}
985 }
986 
987 #ifdef CONFIG_SMP
988 static void __init prefill_possible_map(void)
989 {
990 	int i, possible = num_possible_cpus();
991 
992 	if (possible > nr_cpu_ids)
993 		possible = nr_cpu_ids;
994 
995 	for (i = 0; i < possible; i++)
996 		set_cpu_possible(i, true);
997 	for (; i < NR_CPUS; i++)
998 		set_cpu_possible(i, false);
999 
1000 	nr_cpu_ids = possible;
1001 }
1002 #else
1003 static inline void prefill_possible_map(void) {}
1004 #endif
1005 
1006 void __init setup_arch(char **cmdline_p)
1007 {
1008 	cpu_probe();
1009 	mips_cm_probe();
1010 	prom_init();
1011 
1012 	setup_early_fdc_console();
1013 #ifdef CONFIG_EARLY_PRINTK
1014 	setup_early_printk();
1015 #endif
1016 	cpu_report();
1017 	check_bugs_early();
1018 
1019 #if defined(CONFIG_VT)
1020 #if defined(CONFIG_VGA_CONSOLE)
1021 	conswitchp = &vga_con;
1022 #elif defined(CONFIG_DUMMY_CONSOLE)
1023 	conswitchp = &dummy_con;
1024 #endif
1025 #endif
1026 
1027 	arch_mem_init(cmdline_p);
1028 
1029 	resource_init();
1030 	plat_smp_setup();
1031 	prefill_possible_map();
1032 
1033 	cpu_cache_init();
1034 	paging_init();
1035 }
1036 
1037 unsigned long kernelsp[NR_CPUS];
1038 unsigned long fw_arg0, fw_arg1, fw_arg2, fw_arg3;
1039 
1040 #ifdef CONFIG_USE_OF
1041 unsigned long fw_passed_dtb;
1042 #endif
1043 
1044 #ifdef CONFIG_DEBUG_FS
1045 struct dentry *mips_debugfs_dir;
1046 static int __init debugfs_mips(void)
1047 {
1048 	struct dentry *d;
1049 
1050 	d = debugfs_create_dir("mips", NULL);
1051 	if (!d)
1052 		return -ENOMEM;
1053 	mips_debugfs_dir = d;
1054 	return 0;
1055 }
1056 arch_initcall(debugfs_mips);
1057 #endif
1058