xref: /openbmc/linux/arch/mips/kernel/setup.c (revision 5a244f48)
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 
84 static void *detect_magic __initdata = detect_memory_region;
85 
86 void __init add_memory_region(phys_addr_t start, phys_addr_t size, long type)
87 {
88 	int x = boot_mem_map.nr_map;
89 	int i;
90 
91 	/*
92 	 * If the region reaches the top of the physical address space, adjust
93 	 * the size slightly so that (start + size) doesn't overflow
94 	 */
95 	if (start + size - 1 == (phys_addr_t)ULLONG_MAX)
96 		--size;
97 
98 	/* Sanity check */
99 	if (start + size < start) {
100 		pr_warn("Trying to add an invalid memory region, skipped\n");
101 		return;
102 	}
103 
104 	/*
105 	 * Try to merge with existing entry, if any.
106 	 */
107 	for (i = 0; i < boot_mem_map.nr_map; i++) {
108 		struct boot_mem_map_entry *entry = boot_mem_map.map + i;
109 		unsigned long top;
110 
111 		if (entry->type != type)
112 			continue;
113 
114 		if (start + size < entry->addr)
115 			continue;			/* no overlap */
116 
117 		if (entry->addr + entry->size < start)
118 			continue;			/* no overlap */
119 
120 		top = max(entry->addr + entry->size, start + size);
121 		entry->addr = min(entry->addr, start);
122 		entry->size = top - entry->addr;
123 
124 		return;
125 	}
126 
127 	if (boot_mem_map.nr_map == BOOT_MEM_MAP_MAX) {
128 		pr_err("Ooops! Too many entries in the memory map!\n");
129 		return;
130 	}
131 
132 	boot_mem_map.map[x].addr = start;
133 	boot_mem_map.map[x].size = size;
134 	boot_mem_map.map[x].type = type;
135 	boot_mem_map.nr_map++;
136 }
137 
138 void __init detect_memory_region(phys_addr_t start, phys_addr_t sz_min, phys_addr_t sz_max)
139 {
140 	void *dm = &detect_magic;
141 	phys_addr_t size;
142 
143 	for (size = sz_min; size < sz_max; size <<= 1) {
144 		if (!memcmp(dm, dm + size, sizeof(detect_magic)))
145 			break;
146 	}
147 
148 	pr_debug("Memory: %lluMB of RAM detected at 0x%llx (min: %lluMB, max: %lluMB)\n",
149 		((unsigned long long) size) / SZ_1M,
150 		(unsigned long long) start,
151 		((unsigned long long) sz_min) / SZ_1M,
152 		((unsigned long long) sz_max) / SZ_1M);
153 
154 	add_memory_region(start, size, BOOT_MEM_RAM);
155 }
156 
157 bool __init memory_region_available(phys_addr_t start, phys_addr_t size)
158 {
159 	int i;
160 	bool in_ram = false, free = true;
161 
162 	for (i = 0; i < boot_mem_map.nr_map; i++) {
163 		phys_addr_t start_, end_;
164 
165 		start_ = boot_mem_map.map[i].addr;
166 		end_ = boot_mem_map.map[i].addr + boot_mem_map.map[i].size;
167 
168 		switch (boot_mem_map.map[i].type) {
169 		case BOOT_MEM_RAM:
170 			if (start >= start_ && start + size <= end_)
171 				in_ram = true;
172 			break;
173 		case BOOT_MEM_RESERVED:
174 			if ((start >= start_ && start < end_) ||
175 			    (start < start_ && start + size >= start_))
176 				free = false;
177 			break;
178 		default:
179 			continue;
180 		}
181 	}
182 
183 	return in_ram && free;
184 }
185 
186 static void __init print_memory_map(void)
187 {
188 	int i;
189 	const int field = 2 * sizeof(unsigned long);
190 
191 	for (i = 0; i < boot_mem_map.nr_map; i++) {
192 		printk(KERN_INFO " memory: %0*Lx @ %0*Lx ",
193 		       field, (unsigned long long) boot_mem_map.map[i].size,
194 		       field, (unsigned long long) boot_mem_map.map[i].addr);
195 
196 		switch (boot_mem_map.map[i].type) {
197 		case BOOT_MEM_RAM:
198 			printk(KERN_CONT "(usable)\n");
199 			break;
200 		case BOOT_MEM_INIT_RAM:
201 			printk(KERN_CONT "(usable after init)\n");
202 			break;
203 		case BOOT_MEM_ROM_DATA:
204 			printk(KERN_CONT "(ROM data)\n");
205 			break;
206 		case BOOT_MEM_RESERVED:
207 			printk(KERN_CONT "(reserved)\n");
208 			break;
209 		default:
210 			printk(KERN_CONT "type %lu\n", boot_mem_map.map[i].type);
211 			break;
212 		}
213 	}
214 }
215 
216 /*
217  * Manage initrd
218  */
219 #ifdef CONFIG_BLK_DEV_INITRD
220 
221 static int __init rd_start_early(char *p)
222 {
223 	unsigned long start = memparse(p, &p);
224 
225 #ifdef CONFIG_64BIT
226 	/* Guess if the sign extension was forgotten by bootloader */
227 	if (start < XKPHYS)
228 		start = (int)start;
229 #endif
230 	initrd_start = start;
231 	initrd_end += start;
232 	return 0;
233 }
234 early_param("rd_start", rd_start_early);
235 
236 static int __init rd_size_early(char *p)
237 {
238 	initrd_end += memparse(p, &p);
239 	return 0;
240 }
241 early_param("rd_size", rd_size_early);
242 
243 /* it returns the next free pfn after initrd */
244 static unsigned long __init init_initrd(void)
245 {
246 	unsigned long end;
247 
248 	/*
249 	 * Board specific code or command line parser should have
250 	 * already set up initrd_start and initrd_end. In these cases
251 	 * perfom sanity checks and use them if all looks good.
252 	 */
253 	if (!initrd_start || initrd_end <= initrd_start)
254 		goto disable;
255 
256 	if (initrd_start & ~PAGE_MASK) {
257 		pr_err("initrd start must be page aligned\n");
258 		goto disable;
259 	}
260 	if (initrd_start < PAGE_OFFSET) {
261 		pr_err("initrd start < PAGE_OFFSET\n");
262 		goto disable;
263 	}
264 
265 	/*
266 	 * Sanitize initrd addresses. For example firmware
267 	 * can't guess if they need to pass them through
268 	 * 64-bits values if the kernel has been built in pure
269 	 * 32-bit. We need also to switch from KSEG0 to XKPHYS
270 	 * addresses now, so the code can now safely use __pa().
271 	 */
272 	end = __pa(initrd_end);
273 	initrd_end = (unsigned long)__va(end);
274 	initrd_start = (unsigned long)__va(__pa(initrd_start));
275 
276 	ROOT_DEV = Root_RAM0;
277 	return PFN_UP(end);
278 disable:
279 	initrd_start = 0;
280 	initrd_end = 0;
281 	return 0;
282 }
283 
284 /* In some conditions (e.g. big endian bootloader with a little endian
285    kernel), the initrd might appear byte swapped.  Try to detect this and
286    byte swap it if needed.  */
287 static void __init maybe_bswap_initrd(void)
288 {
289 #if defined(CONFIG_CPU_CAVIUM_OCTEON)
290 	u64 buf;
291 
292 	/* Check for CPIO signature */
293 	if (!memcmp((void *)initrd_start, "070701", 6))
294 		return;
295 
296 	/* Check for compressed initrd */
297 	if (decompress_method((unsigned char *)initrd_start, 8, NULL))
298 		return;
299 
300 	/* Try again with a byte swapped header */
301 	buf = swab64p((u64 *)initrd_start);
302 	if (!memcmp(&buf, "070701", 6) ||
303 	    decompress_method((unsigned char *)(&buf), 8, NULL)) {
304 		unsigned long i;
305 
306 		pr_info("Byteswapped initrd detected\n");
307 		for (i = initrd_start; i < ALIGN(initrd_end, 8); i += 8)
308 			swab64s((u64 *)i);
309 	}
310 #endif
311 }
312 
313 static void __init finalize_initrd(void)
314 {
315 	unsigned long size = initrd_end - initrd_start;
316 
317 	if (size == 0) {
318 		printk(KERN_INFO "Initrd not found or empty");
319 		goto disable;
320 	}
321 	if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
322 		printk(KERN_ERR "Initrd extends beyond end of memory");
323 		goto disable;
324 	}
325 
326 	maybe_bswap_initrd();
327 
328 	reserve_bootmem(__pa(initrd_start), size, BOOTMEM_DEFAULT);
329 	initrd_below_start_ok = 1;
330 
331 	pr_info("Initial ramdisk at: 0x%lx (%lu bytes)\n",
332 		initrd_start, size);
333 	return;
334 disable:
335 	printk(KERN_CONT " - disabling initrd\n");
336 	initrd_start = 0;
337 	initrd_end = 0;
338 }
339 
340 #else  /* !CONFIG_BLK_DEV_INITRD */
341 
342 static unsigned long __init init_initrd(void)
343 {
344 	return 0;
345 }
346 
347 #define finalize_initrd()	do {} while (0)
348 
349 #endif
350 
351 /*
352  * Initialize the bootmem allocator. It also setup initrd related data
353  * if needed.
354  */
355 #if defined(CONFIG_SGI_IP27) || (defined(CONFIG_CPU_LOONGSON3) && defined(CONFIG_NUMA))
356 
357 static void __init bootmem_init(void)
358 {
359 	init_initrd();
360 	finalize_initrd();
361 }
362 
363 #else  /* !CONFIG_SGI_IP27 */
364 
365 static unsigned long __init bootmap_bytes(unsigned long pages)
366 {
367 	unsigned long bytes = DIV_ROUND_UP(pages, 8);
368 
369 	return ALIGN(bytes, sizeof(long));
370 }
371 
372 static void __init bootmem_init(void)
373 {
374 	unsigned long reserved_end;
375 	unsigned long mapstart = ~0UL;
376 	unsigned long bootmap_size;
377 	bool bootmap_valid = false;
378 	int i;
379 
380 	/*
381 	 * Sanity check any INITRD first. We don't take it into account
382 	 * for bootmem setup initially, rely on the end-of-kernel-code
383 	 * as our memory range starting point. Once bootmem is inited we
384 	 * will reserve the area used for the initrd.
385 	 */
386 	init_initrd();
387 	reserved_end = (unsigned long) PFN_UP(__pa_symbol(&_end));
388 
389 	/*
390 	 * max_low_pfn is not a number of pages. The number of pages
391 	 * of the system is given by 'max_low_pfn - min_low_pfn'.
392 	 */
393 	min_low_pfn = ~0UL;
394 	max_low_pfn = 0;
395 
396 	/*
397 	 * Find the highest page frame number we have available.
398 	 */
399 	for (i = 0; i < boot_mem_map.nr_map; i++) {
400 		unsigned long start, end;
401 
402 		if (boot_mem_map.map[i].type != BOOT_MEM_RAM)
403 			continue;
404 
405 		start = PFN_UP(boot_mem_map.map[i].addr);
406 		end = PFN_DOWN(boot_mem_map.map[i].addr
407 				+ boot_mem_map.map[i].size);
408 
409 #ifndef CONFIG_HIGHMEM
410 		/*
411 		 * Skip highmem here so we get an accurate max_low_pfn if low
412 		 * memory stops short of high memory.
413 		 * If the region overlaps HIGHMEM_START, end is clipped so
414 		 * max_pfn excludes the highmem portion.
415 		 */
416 		if (start >= PFN_DOWN(HIGHMEM_START))
417 			continue;
418 		if (end > PFN_DOWN(HIGHMEM_START))
419 			end = PFN_DOWN(HIGHMEM_START);
420 #endif
421 
422 		if (end > max_low_pfn)
423 			max_low_pfn = end;
424 		if (start < min_low_pfn)
425 			min_low_pfn = start;
426 		if (end <= reserved_end)
427 			continue;
428 #ifdef CONFIG_BLK_DEV_INITRD
429 		/* Skip zones before initrd and initrd itself */
430 		if (initrd_end && end <= (unsigned long)PFN_UP(__pa(initrd_end)))
431 			continue;
432 #endif
433 		if (start >= mapstart)
434 			continue;
435 		mapstart = max(reserved_end, start);
436 	}
437 
438 	if (min_low_pfn >= max_low_pfn)
439 		panic("Incorrect memory mapping !!!");
440 	if (min_low_pfn > ARCH_PFN_OFFSET) {
441 		pr_info("Wasting %lu bytes for tracking %lu unused pages\n",
442 			(min_low_pfn - ARCH_PFN_OFFSET) * sizeof(struct page),
443 			min_low_pfn - ARCH_PFN_OFFSET);
444 	} else if (min_low_pfn < ARCH_PFN_OFFSET) {
445 		pr_info("%lu free pages won't be used\n",
446 			ARCH_PFN_OFFSET - min_low_pfn);
447 	}
448 	min_low_pfn = ARCH_PFN_OFFSET;
449 
450 	/*
451 	 * Determine low and high memory ranges
452 	 */
453 	max_pfn = max_low_pfn;
454 	if (max_low_pfn > PFN_DOWN(HIGHMEM_START)) {
455 #ifdef CONFIG_HIGHMEM
456 		highstart_pfn = PFN_DOWN(HIGHMEM_START);
457 		highend_pfn = max_low_pfn;
458 #endif
459 		max_low_pfn = PFN_DOWN(HIGHMEM_START);
460 	}
461 
462 #ifdef CONFIG_BLK_DEV_INITRD
463 	/*
464 	 * mapstart should be after initrd_end
465 	 */
466 	if (initrd_end)
467 		mapstart = max(mapstart, (unsigned long)PFN_UP(__pa(initrd_end)));
468 #endif
469 
470 	/*
471 	 * check that mapstart doesn't overlap with any of
472 	 * memory regions that have been reserved through eg. DTB
473 	 */
474 	bootmap_size = bootmap_bytes(max_low_pfn - min_low_pfn);
475 
476 	bootmap_valid = memory_region_available(PFN_PHYS(mapstart),
477 						bootmap_size);
478 	for (i = 0; i < boot_mem_map.nr_map && !bootmap_valid; i++) {
479 		unsigned long mapstart_addr;
480 
481 		switch (boot_mem_map.map[i].type) {
482 		case BOOT_MEM_RESERVED:
483 			mapstart_addr = PFN_ALIGN(boot_mem_map.map[i].addr +
484 						boot_mem_map.map[i].size);
485 			if (PHYS_PFN(mapstart_addr) < mapstart)
486 				break;
487 
488 			bootmap_valid = memory_region_available(mapstart_addr,
489 								bootmap_size);
490 			if (bootmap_valid)
491 				mapstart = PHYS_PFN(mapstart_addr);
492 			break;
493 		default:
494 			break;
495 		}
496 	}
497 
498 	if (!bootmap_valid)
499 		panic("No memory area to place a bootmap bitmap");
500 
501 	/*
502 	 * Initialize the boot-time allocator with low memory only.
503 	 */
504 	if (bootmap_size != init_bootmem_node(NODE_DATA(0), mapstart,
505 					 min_low_pfn, max_low_pfn))
506 		panic("Unexpected memory size required for bootmap");
507 
508 	for (i = 0; i < boot_mem_map.nr_map; i++) {
509 		unsigned long start, end;
510 
511 		start = PFN_UP(boot_mem_map.map[i].addr);
512 		end = PFN_DOWN(boot_mem_map.map[i].addr
513 				+ boot_mem_map.map[i].size);
514 
515 		if (start <= min_low_pfn)
516 			start = min_low_pfn;
517 		if (start >= end)
518 			continue;
519 
520 #ifndef CONFIG_HIGHMEM
521 		if (end > max_low_pfn)
522 			end = max_low_pfn;
523 
524 		/*
525 		 * ... finally, is the area going away?
526 		 */
527 		if (end <= start)
528 			continue;
529 #endif
530 
531 		memblock_add_node(PFN_PHYS(start), PFN_PHYS(end - start), 0);
532 	}
533 
534 	/*
535 	 * Register fully available low RAM pages with the bootmem allocator.
536 	 */
537 	for (i = 0; i < boot_mem_map.nr_map; i++) {
538 		unsigned long start, end, size;
539 
540 		start = PFN_UP(boot_mem_map.map[i].addr);
541 		end   = PFN_DOWN(boot_mem_map.map[i].addr
542 				    + boot_mem_map.map[i].size);
543 
544 		/*
545 		 * Reserve usable memory.
546 		 */
547 		switch (boot_mem_map.map[i].type) {
548 		case BOOT_MEM_RAM:
549 			break;
550 		case BOOT_MEM_INIT_RAM:
551 			memory_present(0, start, end);
552 			continue;
553 		default:
554 			/* Not usable memory */
555 			if (start > min_low_pfn && end < max_low_pfn)
556 				reserve_bootmem(boot_mem_map.map[i].addr,
557 						boot_mem_map.map[i].size,
558 						BOOTMEM_DEFAULT);
559 			continue;
560 		}
561 
562 		/*
563 		 * We are rounding up the start address of usable memory
564 		 * and at the end of the usable range downwards.
565 		 */
566 		if (start >= max_low_pfn)
567 			continue;
568 		if (start < reserved_end)
569 			start = reserved_end;
570 		if (end > max_low_pfn)
571 			end = max_low_pfn;
572 
573 		/*
574 		 * ... finally, is the area going away?
575 		 */
576 		if (end <= start)
577 			continue;
578 		size = end - start;
579 
580 		/* Register lowmem ranges */
581 		free_bootmem(PFN_PHYS(start), size << PAGE_SHIFT);
582 		memory_present(0, start, end);
583 	}
584 
585 	/*
586 	 * Reserve the bootmap memory.
587 	 */
588 	reserve_bootmem(PFN_PHYS(mapstart), bootmap_size, BOOTMEM_DEFAULT);
589 
590 #ifdef CONFIG_RELOCATABLE
591 	/*
592 	 * The kernel reserves all memory below its _end symbol as bootmem,
593 	 * but the kernel may now be at a much higher address. The memory
594 	 * between the original and new locations may be returned to the system.
595 	 */
596 	if (__pa_symbol(_text) > __pa_symbol(VMLINUX_LOAD_ADDRESS)) {
597 		unsigned long offset;
598 		extern void show_kernel_relocation(const char *level);
599 
600 		offset = __pa_symbol(_text) - __pa_symbol(VMLINUX_LOAD_ADDRESS);
601 		free_bootmem(__pa_symbol(VMLINUX_LOAD_ADDRESS), offset);
602 
603 #if defined(CONFIG_DEBUG_KERNEL) && defined(CONFIG_DEBUG_INFO)
604 		/*
605 		 * This information is necessary when debugging the kernel
606 		 * But is a security vulnerability otherwise!
607 		 */
608 		show_kernel_relocation(KERN_INFO);
609 #endif
610 	}
611 #endif
612 
613 	/*
614 	 * Reserve initrd memory if needed.
615 	 */
616 	finalize_initrd();
617 }
618 
619 #endif	/* CONFIG_SGI_IP27 */
620 
621 /*
622  * arch_mem_init - initialize memory management subsystem
623  *
624  *  o plat_mem_setup() detects the memory configuration and will record detected
625  *    memory areas using add_memory_region.
626  *
627  * At this stage the memory configuration of the system is known to the
628  * kernel but generic memory management system is still entirely uninitialized.
629  *
630  *  o bootmem_init()
631  *  o sparse_init()
632  *  o paging_init()
633  *  o dma_contiguous_reserve()
634  *
635  * At this stage the bootmem allocator is ready to use.
636  *
637  * NOTE: historically plat_mem_setup did the entire platform initialization.
638  *	 This was rather impractical because it meant plat_mem_setup had to
639  * get away without any kind of memory allocator.  To keep old code from
640  * breaking plat_setup was just renamed to plat_mem_setup and a second platform
641  * initialization hook for anything else was introduced.
642  */
643 
644 static int usermem __initdata;
645 
646 static int __init early_parse_mem(char *p)
647 {
648 	phys_addr_t start, size;
649 
650 	/*
651 	 * If a user specifies memory size, we
652 	 * blow away any automatically generated
653 	 * size.
654 	 */
655 	if (usermem == 0) {
656 		boot_mem_map.nr_map = 0;
657 		usermem = 1;
658 	}
659 	start = 0;
660 	size = memparse(p, &p);
661 	if (*p == '@')
662 		start = memparse(p + 1, &p);
663 
664 	add_memory_region(start, size, BOOT_MEM_RAM);
665 
666 	if (start && start > PHYS_OFFSET)
667 		add_memory_region(PHYS_OFFSET, start - PHYS_OFFSET,
668 				BOOT_MEM_RESERVED);
669 	return 0;
670 }
671 early_param("mem", early_parse_mem);
672 
673 static int __init early_parse_memmap(char *p)
674 {
675 	char *oldp;
676 	u64 start_at, mem_size;
677 
678 	if (!p)
679 		return -EINVAL;
680 
681 	if (!strncmp(p, "exactmap", 8)) {
682 		pr_err("\"memmap=exactmap\" invalid on MIPS\n");
683 		return 0;
684 	}
685 
686 	oldp = p;
687 	mem_size = memparse(p, &p);
688 	if (p == oldp)
689 		return -EINVAL;
690 
691 	if (*p == '@') {
692 		start_at = memparse(p+1, &p);
693 		add_memory_region(start_at, mem_size, BOOT_MEM_RAM);
694 	} else if (*p == '#') {
695 		pr_err("\"memmap=nn#ss\" (force ACPI data) invalid on MIPS\n");
696 		return -EINVAL;
697 	} else if (*p == '$') {
698 		start_at = memparse(p+1, &p);
699 		add_memory_region(start_at, mem_size, BOOT_MEM_RESERVED);
700 	} else {
701 		pr_err("\"memmap\" invalid format!\n");
702 		return -EINVAL;
703 	}
704 
705 	if (*p == '\0') {
706 		usermem = 1;
707 		return 0;
708 	} else
709 		return -EINVAL;
710 }
711 early_param("memmap", early_parse_memmap);
712 
713 #ifdef CONFIG_PROC_VMCORE
714 unsigned long setup_elfcorehdr, setup_elfcorehdr_size;
715 static int __init early_parse_elfcorehdr(char *p)
716 {
717 	int i;
718 
719 	setup_elfcorehdr = memparse(p, &p);
720 
721 	for (i = 0; i < boot_mem_map.nr_map; i++) {
722 		unsigned long start = boot_mem_map.map[i].addr;
723 		unsigned long end = (boot_mem_map.map[i].addr +
724 				     boot_mem_map.map[i].size);
725 		if (setup_elfcorehdr >= start && setup_elfcorehdr < end) {
726 			/*
727 			 * Reserve from the elf core header to the end of
728 			 * the memory segment, that should all be kdump
729 			 * reserved memory.
730 			 */
731 			setup_elfcorehdr_size = end - setup_elfcorehdr;
732 			break;
733 		}
734 	}
735 	/*
736 	 * If we don't find it in the memory map, then we shouldn't
737 	 * have to worry about it, as the new kernel won't use it.
738 	 */
739 	return 0;
740 }
741 early_param("elfcorehdr", early_parse_elfcorehdr);
742 #endif
743 
744 static void __init arch_mem_addpart(phys_addr_t mem, phys_addr_t end, int type)
745 {
746 	phys_addr_t size;
747 	int i;
748 
749 	size = end - mem;
750 	if (!size)
751 		return;
752 
753 	/* Make sure it is in the boot_mem_map */
754 	for (i = 0; i < boot_mem_map.nr_map; i++) {
755 		if (mem >= boot_mem_map.map[i].addr &&
756 		    mem < (boot_mem_map.map[i].addr +
757 			   boot_mem_map.map[i].size))
758 			return;
759 	}
760 	add_memory_region(mem, size, type);
761 }
762 
763 #ifdef CONFIG_KEXEC
764 static inline unsigned long long get_total_mem(void)
765 {
766 	unsigned long long total;
767 
768 	total = max_pfn - min_low_pfn;
769 	return total << PAGE_SHIFT;
770 }
771 
772 static void __init mips_parse_crashkernel(void)
773 {
774 	unsigned long long total_mem;
775 	unsigned long long crash_size, crash_base;
776 	int ret;
777 
778 	total_mem = get_total_mem();
779 	ret = parse_crashkernel(boot_command_line, total_mem,
780 				&crash_size, &crash_base);
781 	if (ret != 0 || crash_size <= 0)
782 		return;
783 
784 	if (!memory_region_available(crash_base, crash_size)) {
785 		pr_warn("Invalid memory region reserved for crash kernel\n");
786 		return;
787 	}
788 
789 	crashk_res.start = crash_base;
790 	crashk_res.end	 = crash_base + crash_size - 1;
791 }
792 
793 static void __init request_crashkernel(struct resource *res)
794 {
795 	int ret;
796 
797 	if (crashk_res.start == crashk_res.end)
798 		return;
799 
800 	ret = request_resource(res, &crashk_res);
801 	if (!ret)
802 		pr_info("Reserving %ldMB of memory at %ldMB for crashkernel\n",
803 			(unsigned long)((crashk_res.end -
804 					 crashk_res.start + 1) >> 20),
805 			(unsigned long)(crashk_res.start  >> 20));
806 }
807 #else /* !defined(CONFIG_KEXEC)		*/
808 static void __init mips_parse_crashkernel(void)
809 {
810 }
811 
812 static void __init request_crashkernel(struct resource *res)
813 {
814 }
815 #endif /* !defined(CONFIG_KEXEC)  */
816 
817 #define USE_PROM_CMDLINE	IS_ENABLED(CONFIG_MIPS_CMDLINE_FROM_BOOTLOADER)
818 #define USE_DTB_CMDLINE		IS_ENABLED(CONFIG_MIPS_CMDLINE_FROM_DTB)
819 #define EXTEND_WITH_PROM	IS_ENABLED(CONFIG_MIPS_CMDLINE_DTB_EXTEND)
820 #define BUILTIN_EXTEND_WITH_PROM	\
821 	IS_ENABLED(CONFIG_MIPS_CMDLINE_BUILTIN_EXTEND)
822 
823 static void __init arch_mem_init(char **cmdline_p)
824 {
825 	struct memblock_region *reg;
826 	extern void plat_mem_setup(void);
827 
828 	/* call board setup routine */
829 	plat_mem_setup();
830 
831 	/*
832 	 * Make sure all kernel memory is in the maps.  The "UP" and
833 	 * "DOWN" are opposite for initdata since if it crosses over
834 	 * into another memory section you don't want that to be
835 	 * freed when the initdata is freed.
836 	 */
837 	arch_mem_addpart(PFN_DOWN(__pa_symbol(&_text)) << PAGE_SHIFT,
838 			 PFN_UP(__pa_symbol(&_edata)) << PAGE_SHIFT,
839 			 BOOT_MEM_RAM);
840 	arch_mem_addpart(PFN_UP(__pa_symbol(&__init_begin)) << PAGE_SHIFT,
841 			 PFN_DOWN(__pa_symbol(&__init_end)) << PAGE_SHIFT,
842 			 BOOT_MEM_INIT_RAM);
843 
844 	pr_info("Determined physical RAM map:\n");
845 	print_memory_map();
846 
847 #if defined(CONFIG_CMDLINE_BOOL) && defined(CONFIG_CMDLINE_OVERRIDE)
848 	strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
849 #else
850 	if ((USE_PROM_CMDLINE && arcs_cmdline[0]) ||
851 	    (USE_DTB_CMDLINE && !boot_command_line[0]))
852 		strlcpy(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);
853 
854 	if (EXTEND_WITH_PROM && arcs_cmdline[0]) {
855 		if (boot_command_line[0])
856 			strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
857 		strlcat(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);
858 	}
859 
860 #if defined(CONFIG_CMDLINE_BOOL)
861 	if (builtin_cmdline[0]) {
862 		if (boot_command_line[0])
863 			strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
864 		strlcat(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
865 	}
866 
867 	if (BUILTIN_EXTEND_WITH_PROM && arcs_cmdline[0]) {
868 		if (boot_command_line[0])
869 			strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
870 		strlcat(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);
871 	}
872 #endif
873 #endif
874 	strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
875 
876 	*cmdline_p = command_line;
877 
878 	parse_early_param();
879 
880 	if (usermem) {
881 		pr_info("User-defined physical RAM map:\n");
882 		print_memory_map();
883 	}
884 
885 	early_init_fdt_reserve_self();
886 	early_init_fdt_scan_reserved_mem();
887 
888 	bootmem_init();
889 #ifdef CONFIG_PROC_VMCORE
890 	if (setup_elfcorehdr && setup_elfcorehdr_size) {
891 		printk(KERN_INFO "kdump reserved memory at %lx-%lx\n",
892 		       setup_elfcorehdr, setup_elfcorehdr_size);
893 		reserve_bootmem(setup_elfcorehdr, setup_elfcorehdr_size,
894 				BOOTMEM_DEFAULT);
895 	}
896 #endif
897 
898 	mips_parse_crashkernel();
899 #ifdef CONFIG_KEXEC
900 	if (crashk_res.start != crashk_res.end)
901 		reserve_bootmem(crashk_res.start,
902 				crashk_res.end - crashk_res.start + 1,
903 				BOOTMEM_DEFAULT);
904 #endif
905 	device_tree_init();
906 	sparse_init();
907 	plat_swiotlb_setup();
908 
909 	dma_contiguous_reserve(PFN_PHYS(max_low_pfn));
910 	/* Tell bootmem about cma reserved memblock section */
911 	for_each_memblock(reserved, reg)
912 		if (reg->size != 0)
913 			reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT);
914 
915 	reserve_bootmem_region(__pa_symbol(&__nosave_begin),
916 			__pa_symbol(&__nosave_end)); /* Reserve for hibernation */
917 }
918 
919 static void __init resource_init(void)
920 {
921 	int i;
922 
923 	if (UNCAC_BASE != IO_BASE)
924 		return;
925 
926 	code_resource.start = __pa_symbol(&_text);
927 	code_resource.end = __pa_symbol(&_etext) - 1;
928 	data_resource.start = __pa_symbol(&_etext);
929 	data_resource.end = __pa_symbol(&_edata) - 1;
930 
931 	for (i = 0; i < boot_mem_map.nr_map; i++) {
932 		struct resource *res;
933 		unsigned long start, end;
934 
935 		start = boot_mem_map.map[i].addr;
936 		end = boot_mem_map.map[i].addr + boot_mem_map.map[i].size - 1;
937 		if (start >= HIGHMEM_START)
938 			continue;
939 		if (end >= HIGHMEM_START)
940 			end = HIGHMEM_START - 1;
941 
942 		res = alloc_bootmem(sizeof(struct resource));
943 
944 		res->start = start;
945 		res->end = end;
946 		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
947 
948 		switch (boot_mem_map.map[i].type) {
949 		case BOOT_MEM_RAM:
950 		case BOOT_MEM_INIT_RAM:
951 		case BOOT_MEM_ROM_DATA:
952 			res->name = "System RAM";
953 			res->flags |= IORESOURCE_SYSRAM;
954 			break;
955 		case BOOT_MEM_RESERVED:
956 		default:
957 			res->name = "reserved";
958 		}
959 
960 		request_resource(&iomem_resource, res);
961 
962 		/*
963 		 *  We don't know which RAM region contains kernel data,
964 		 *  so we try it repeatedly and let the resource manager
965 		 *  test it.
966 		 */
967 		request_resource(res, &code_resource);
968 		request_resource(res, &data_resource);
969 		request_crashkernel(res);
970 	}
971 }
972 
973 #ifdef CONFIG_SMP
974 static void __init prefill_possible_map(void)
975 {
976 	int i, possible = num_possible_cpus();
977 
978 	if (possible > nr_cpu_ids)
979 		possible = nr_cpu_ids;
980 
981 	for (i = 0; i < possible; i++)
982 		set_cpu_possible(i, true);
983 	for (; i < NR_CPUS; i++)
984 		set_cpu_possible(i, false);
985 
986 	nr_cpu_ids = possible;
987 }
988 #else
989 static inline void prefill_possible_map(void) {}
990 #endif
991 
992 void __init setup_arch(char **cmdline_p)
993 {
994 	cpu_probe();
995 	mips_cm_probe();
996 	prom_init();
997 
998 	setup_early_fdc_console();
999 #ifdef CONFIG_EARLY_PRINTK
1000 	setup_early_printk();
1001 #endif
1002 	cpu_report();
1003 	check_bugs_early();
1004 
1005 #if defined(CONFIG_VT)
1006 #if defined(CONFIG_VGA_CONSOLE)
1007 	conswitchp = &vga_con;
1008 #elif defined(CONFIG_DUMMY_CONSOLE)
1009 	conswitchp = &dummy_con;
1010 #endif
1011 #endif
1012 
1013 	arch_mem_init(cmdline_p);
1014 
1015 	resource_init();
1016 	plat_smp_setup();
1017 	prefill_possible_map();
1018 
1019 	cpu_cache_init();
1020 	paging_init();
1021 }
1022 
1023 unsigned long kernelsp[NR_CPUS];
1024 unsigned long fw_arg0, fw_arg1, fw_arg2, fw_arg3;
1025 
1026 #ifdef CONFIG_USE_OF
1027 unsigned long fw_passed_dtb;
1028 #endif
1029 
1030 #ifdef CONFIG_DEBUG_FS
1031 struct dentry *mips_debugfs_dir;
1032 static int __init debugfs_mips(void)
1033 {
1034 	struct dentry *d;
1035 
1036 	d = debugfs_create_dir("mips", NULL);
1037 	if (!d)
1038 		return -ENOMEM;
1039 	mips_debugfs_dir = d;
1040 	return 0;
1041 }
1042 arch_initcall(debugfs_mips);
1043 #endif
1044