xref: /openbmc/linux/arch/mips/kernel/setup.c (revision 82e6fdd6)
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_t)ULLONG_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 bool __init memory_region_available(phys_addr_t start, phys_addr_t size)
159 {
160 	int i;
161 	bool in_ram = false, free = true;
162 
163 	for (i = 0; i < boot_mem_map.nr_map; i++) {
164 		phys_addr_t start_, end_;
165 
166 		start_ = boot_mem_map.map[i].addr;
167 		end_ = boot_mem_map.map[i].addr + boot_mem_map.map[i].size;
168 
169 		switch (boot_mem_map.map[i].type) {
170 		case BOOT_MEM_RAM:
171 			if (start >= start_ && start + size <= end_)
172 				in_ram = true;
173 			break;
174 		case BOOT_MEM_RESERVED:
175 			if ((start >= start_ && start < end_) ||
176 			    (start < start_ && start + size >= start_))
177 				free = false;
178 			break;
179 		default:
180 			continue;
181 		}
182 	}
183 
184 	return in_ram && free;
185 }
186 
187 static void __init print_memory_map(void)
188 {
189 	int i;
190 	const int field = 2 * sizeof(unsigned long);
191 
192 	for (i = 0; i < boot_mem_map.nr_map; i++) {
193 		printk(KERN_INFO " memory: %0*Lx @ %0*Lx ",
194 		       field, (unsigned long long) boot_mem_map.map[i].size,
195 		       field, (unsigned long long) boot_mem_map.map[i].addr);
196 
197 		switch (boot_mem_map.map[i].type) {
198 		case BOOT_MEM_RAM:
199 			printk(KERN_CONT "(usable)\n");
200 			break;
201 		case BOOT_MEM_INIT_RAM:
202 			printk(KERN_CONT "(usable after init)\n");
203 			break;
204 		case BOOT_MEM_ROM_DATA:
205 			printk(KERN_CONT "(ROM data)\n");
206 			break;
207 		case BOOT_MEM_RESERVED:
208 			printk(KERN_CONT "(reserved)\n");
209 			break;
210 		default:
211 			printk(KERN_CONT "type %lu\n", boot_mem_map.map[i].type);
212 			break;
213 		}
214 	}
215 }
216 
217 /*
218  * Manage initrd
219  */
220 #ifdef CONFIG_BLK_DEV_INITRD
221 
222 static int __init rd_start_early(char *p)
223 {
224 	unsigned long start = memparse(p, &p);
225 
226 #ifdef CONFIG_64BIT
227 	/* Guess if the sign extension was forgotten by bootloader */
228 	if (start < XKPHYS)
229 		start = (int)start;
230 #endif
231 	initrd_start = start;
232 	initrd_end += start;
233 	return 0;
234 }
235 early_param("rd_start", rd_start_early);
236 
237 static int __init rd_size_early(char *p)
238 {
239 	initrd_end += memparse(p, &p);
240 	return 0;
241 }
242 early_param("rd_size", rd_size_early);
243 
244 /* it returns the next free pfn after initrd */
245 static unsigned long __init init_initrd(void)
246 {
247 	unsigned long end;
248 
249 	/*
250 	 * Board specific code or command line parser should have
251 	 * already set up initrd_start and initrd_end. In these cases
252 	 * perfom sanity checks and use them if all looks good.
253 	 */
254 	if (!initrd_start || initrd_end <= initrd_start)
255 		goto disable;
256 
257 	if (initrd_start & ~PAGE_MASK) {
258 		pr_err("initrd start must be page aligned\n");
259 		goto disable;
260 	}
261 	if (initrd_start < PAGE_OFFSET) {
262 		pr_err("initrd start < PAGE_OFFSET\n");
263 		goto disable;
264 	}
265 
266 	/*
267 	 * Sanitize initrd addresses. For example firmware
268 	 * can't guess if they need to pass them through
269 	 * 64-bits values if the kernel has been built in pure
270 	 * 32-bit. We need also to switch from KSEG0 to XKPHYS
271 	 * addresses now, so the code can now safely use __pa().
272 	 */
273 	end = __pa(initrd_end);
274 	initrd_end = (unsigned long)__va(end);
275 	initrd_start = (unsigned long)__va(__pa(initrd_start));
276 
277 	ROOT_DEV = Root_RAM0;
278 	return PFN_UP(end);
279 disable:
280 	initrd_start = 0;
281 	initrd_end = 0;
282 	return 0;
283 }
284 
285 /* In some conditions (e.g. big endian bootloader with a little endian
286    kernel), the initrd might appear byte swapped.  Try to detect this and
287    byte swap it if needed.  */
288 static void __init maybe_bswap_initrd(void)
289 {
290 #if defined(CONFIG_CPU_CAVIUM_OCTEON)
291 	u64 buf;
292 
293 	/* Check for CPIO signature */
294 	if (!memcmp((void *)initrd_start, "070701", 6))
295 		return;
296 
297 	/* Check for compressed initrd */
298 	if (decompress_method((unsigned char *)initrd_start, 8, NULL))
299 		return;
300 
301 	/* Try again with a byte swapped header */
302 	buf = swab64p((u64 *)initrd_start);
303 	if (!memcmp(&buf, "070701", 6) ||
304 	    decompress_method((unsigned char *)(&buf), 8, NULL)) {
305 		unsigned long i;
306 
307 		pr_info("Byteswapped initrd detected\n");
308 		for (i = initrd_start; i < ALIGN(initrd_end, 8); i += 8)
309 			swab64s((u64 *)i);
310 	}
311 #endif
312 }
313 
314 static void __init finalize_initrd(void)
315 {
316 	unsigned long size = initrd_end - initrd_start;
317 
318 	if (size == 0) {
319 		printk(KERN_INFO "Initrd not found or empty");
320 		goto disable;
321 	}
322 	if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
323 		printk(KERN_ERR "Initrd extends beyond end of memory");
324 		goto disable;
325 	}
326 
327 	maybe_bswap_initrd();
328 
329 	reserve_bootmem(__pa(initrd_start), size, BOOTMEM_DEFAULT);
330 	initrd_below_start_ok = 1;
331 
332 	pr_info("Initial ramdisk at: 0x%lx (%lu bytes)\n",
333 		initrd_start, size);
334 	return;
335 disable:
336 	printk(KERN_CONT " - disabling initrd\n");
337 	initrd_start = 0;
338 	initrd_end = 0;
339 }
340 
341 #else  /* !CONFIG_BLK_DEV_INITRD */
342 
343 static unsigned long __init init_initrd(void)
344 {
345 	return 0;
346 }
347 
348 #define finalize_initrd()	do {} while (0)
349 
350 #endif
351 
352 /*
353  * Initialize the bootmem allocator. It also setup initrd related data
354  * if needed.
355  */
356 #if defined(CONFIG_SGI_IP27) || (defined(CONFIG_CPU_LOONGSON3) && defined(CONFIG_NUMA))
357 
358 static void __init bootmem_init(void)
359 {
360 	init_initrd();
361 	finalize_initrd();
362 }
363 
364 #else  /* !CONFIG_SGI_IP27 */
365 
366 static unsigned long __init bootmap_bytes(unsigned long pages)
367 {
368 	unsigned long bytes = DIV_ROUND_UP(pages, 8);
369 
370 	return ALIGN(bytes, sizeof(long));
371 }
372 
373 static void __init bootmem_init(void)
374 {
375 	unsigned long reserved_end;
376 	unsigned long mapstart = ~0UL;
377 	unsigned long bootmap_size;
378 	phys_addr_t ramstart = (phys_addr_t)ULLONG_MAX;
379 	bool bootmap_valid = false;
380 	int i;
381 
382 	/*
383 	 * Sanity check any INITRD first. We don't take it into account
384 	 * for bootmem setup initially, rely on the end-of-kernel-code
385 	 * as our memory range starting point. Once bootmem is inited we
386 	 * will reserve the area used for the initrd.
387 	 */
388 	init_initrd();
389 	reserved_end = (unsigned long) PFN_UP(__pa_symbol(&_end));
390 
391 	/*
392 	 * max_low_pfn is not a number of pages. The number of pages
393 	 * of the system is given by 'max_low_pfn - min_low_pfn'.
394 	 */
395 	min_low_pfn = ~0UL;
396 	max_low_pfn = 0;
397 
398 	/*
399 	 * Find the highest page frame number we have available
400 	 * and the lowest used RAM address
401 	 */
402 	for (i = 0; i < boot_mem_map.nr_map; i++) {
403 		unsigned long start, end;
404 
405 		if (boot_mem_map.map[i].type != BOOT_MEM_RAM)
406 			continue;
407 
408 		start = PFN_UP(boot_mem_map.map[i].addr);
409 		end = PFN_DOWN(boot_mem_map.map[i].addr
410 				+ boot_mem_map.map[i].size);
411 
412 		ramstart = min(ramstart, boot_mem_map.map[i].addr);
413 
414 #ifndef CONFIG_HIGHMEM
415 		/*
416 		 * Skip highmem here so we get an accurate max_low_pfn if low
417 		 * memory stops short of high memory.
418 		 * If the region overlaps HIGHMEM_START, end is clipped so
419 		 * max_pfn excludes the highmem portion.
420 		 */
421 		if (start >= PFN_DOWN(HIGHMEM_START))
422 			continue;
423 		if (end > PFN_DOWN(HIGHMEM_START))
424 			end = PFN_DOWN(HIGHMEM_START);
425 #endif
426 
427 		if (end > max_low_pfn)
428 			max_low_pfn = end;
429 		if (start < min_low_pfn)
430 			min_low_pfn = start;
431 		if (end <= reserved_end)
432 			continue;
433 #ifdef CONFIG_BLK_DEV_INITRD
434 		/* Skip zones before initrd and initrd itself */
435 		if (initrd_end && end <= (unsigned long)PFN_UP(__pa(initrd_end)))
436 			continue;
437 #endif
438 		if (start >= mapstart)
439 			continue;
440 		mapstart = max(reserved_end, start);
441 	}
442 
443 	/*
444 	 * Reserve any memory between the start of RAM and PHYS_OFFSET
445 	 */
446 	if (ramstart > PHYS_OFFSET)
447 		add_memory_region(PHYS_OFFSET, ramstart - PHYS_OFFSET,
448 				  BOOT_MEM_RESERVED);
449 
450 	if (min_low_pfn >= max_low_pfn)
451 		panic("Incorrect memory mapping !!!");
452 	if (min_low_pfn > ARCH_PFN_OFFSET) {
453 		pr_info("Wasting %lu bytes for tracking %lu unused pages\n",
454 			(min_low_pfn - ARCH_PFN_OFFSET) * sizeof(struct page),
455 			min_low_pfn - ARCH_PFN_OFFSET);
456 	} else if (min_low_pfn < ARCH_PFN_OFFSET) {
457 		pr_info("%lu free pages won't be used\n",
458 			ARCH_PFN_OFFSET - min_low_pfn);
459 	}
460 	min_low_pfn = ARCH_PFN_OFFSET;
461 
462 	/*
463 	 * Determine low and high memory ranges
464 	 */
465 	max_pfn = max_low_pfn;
466 	if (max_low_pfn > PFN_DOWN(HIGHMEM_START)) {
467 #ifdef CONFIG_HIGHMEM
468 		highstart_pfn = PFN_DOWN(HIGHMEM_START);
469 		highend_pfn = max_low_pfn;
470 #endif
471 		max_low_pfn = PFN_DOWN(HIGHMEM_START);
472 	}
473 
474 #ifdef CONFIG_BLK_DEV_INITRD
475 	/*
476 	 * mapstart should be after initrd_end
477 	 */
478 	if (initrd_end)
479 		mapstart = max(mapstart, (unsigned long)PFN_UP(__pa(initrd_end)));
480 #endif
481 
482 	/*
483 	 * check that mapstart doesn't overlap with any of
484 	 * memory regions that have been reserved through eg. DTB
485 	 */
486 	bootmap_size = bootmap_bytes(max_low_pfn - min_low_pfn);
487 
488 	bootmap_valid = memory_region_available(PFN_PHYS(mapstart),
489 						bootmap_size);
490 	for (i = 0; i < boot_mem_map.nr_map && !bootmap_valid; i++) {
491 		unsigned long mapstart_addr;
492 
493 		switch (boot_mem_map.map[i].type) {
494 		case BOOT_MEM_RESERVED:
495 			mapstart_addr = PFN_ALIGN(boot_mem_map.map[i].addr +
496 						boot_mem_map.map[i].size);
497 			if (PHYS_PFN(mapstart_addr) < mapstart)
498 				break;
499 
500 			bootmap_valid = memory_region_available(mapstart_addr,
501 								bootmap_size);
502 			if (bootmap_valid)
503 				mapstart = PHYS_PFN(mapstart_addr);
504 			break;
505 		default:
506 			break;
507 		}
508 	}
509 
510 	if (!bootmap_valid)
511 		panic("No memory area to place a bootmap bitmap");
512 
513 	/*
514 	 * Initialize the boot-time allocator with low memory only.
515 	 */
516 	if (bootmap_size != init_bootmem_node(NODE_DATA(0), mapstart,
517 					 min_low_pfn, max_low_pfn))
518 		panic("Unexpected memory size required for bootmap");
519 
520 	for (i = 0; i < boot_mem_map.nr_map; i++) {
521 		unsigned long start, end;
522 
523 		start = PFN_UP(boot_mem_map.map[i].addr);
524 		end = PFN_DOWN(boot_mem_map.map[i].addr
525 				+ boot_mem_map.map[i].size);
526 
527 		if (start <= min_low_pfn)
528 			start = min_low_pfn;
529 		if (start >= end)
530 			continue;
531 
532 #ifndef CONFIG_HIGHMEM
533 		if (end > max_low_pfn)
534 			end = max_low_pfn;
535 
536 		/*
537 		 * ... finally, is the area going away?
538 		 */
539 		if (end <= start)
540 			continue;
541 #endif
542 
543 		memblock_add_node(PFN_PHYS(start), PFN_PHYS(end - start), 0);
544 	}
545 
546 	/*
547 	 * Register fully available low RAM pages with the bootmem allocator.
548 	 */
549 	for (i = 0; i < boot_mem_map.nr_map; i++) {
550 		unsigned long start, end, size;
551 
552 		start = PFN_UP(boot_mem_map.map[i].addr);
553 		end   = PFN_DOWN(boot_mem_map.map[i].addr
554 				    + boot_mem_map.map[i].size);
555 
556 		/*
557 		 * Reserve usable memory.
558 		 */
559 		switch (boot_mem_map.map[i].type) {
560 		case BOOT_MEM_RAM:
561 			break;
562 		case BOOT_MEM_INIT_RAM:
563 			memory_present(0, start, end);
564 			continue;
565 		default:
566 			/* Not usable memory */
567 			if (start > min_low_pfn && end < max_low_pfn)
568 				reserve_bootmem(boot_mem_map.map[i].addr,
569 						boot_mem_map.map[i].size,
570 						BOOTMEM_DEFAULT);
571 			continue;
572 		}
573 
574 		/*
575 		 * We are rounding up the start address of usable memory
576 		 * and at the end of the usable range downwards.
577 		 */
578 		if (start >= max_low_pfn)
579 			continue;
580 		if (start < reserved_end)
581 			start = reserved_end;
582 		if (end > max_low_pfn)
583 			end = max_low_pfn;
584 
585 		/*
586 		 * ... finally, is the area going away?
587 		 */
588 		if (end <= start)
589 			continue;
590 		size = end - start;
591 
592 		/* Register lowmem ranges */
593 		free_bootmem(PFN_PHYS(start), size << PAGE_SHIFT);
594 		memory_present(0, start, end);
595 	}
596 
597 	/*
598 	 * Reserve the bootmap memory.
599 	 */
600 	reserve_bootmem(PFN_PHYS(mapstart), bootmap_size, BOOTMEM_DEFAULT);
601 
602 #ifdef CONFIG_RELOCATABLE
603 	/*
604 	 * The kernel reserves all memory below its _end symbol as bootmem,
605 	 * but the kernel may now be at a much higher address. The memory
606 	 * between the original and new locations may be returned to the system.
607 	 */
608 	if (__pa_symbol(_text) > __pa_symbol(VMLINUX_LOAD_ADDRESS)) {
609 		unsigned long offset;
610 		extern void show_kernel_relocation(const char *level);
611 
612 		offset = __pa_symbol(_text) - __pa_symbol(VMLINUX_LOAD_ADDRESS);
613 		free_bootmem(__pa_symbol(VMLINUX_LOAD_ADDRESS), offset);
614 
615 #if defined(CONFIG_DEBUG_KERNEL) && defined(CONFIG_DEBUG_INFO)
616 		/*
617 		 * This information is necessary when debugging the kernel
618 		 * But is a security vulnerability otherwise!
619 		 */
620 		show_kernel_relocation(KERN_INFO);
621 #endif
622 	}
623 #endif
624 
625 	/*
626 	 * Reserve initrd memory if needed.
627 	 */
628 	finalize_initrd();
629 }
630 
631 #endif	/* CONFIG_SGI_IP27 */
632 
633 /*
634  * arch_mem_init - initialize memory management subsystem
635  *
636  *  o plat_mem_setup() detects the memory configuration and will record detected
637  *    memory areas using add_memory_region.
638  *
639  * At this stage the memory configuration of the system is known to the
640  * kernel but generic memory management system is still entirely uninitialized.
641  *
642  *  o bootmem_init()
643  *  o sparse_init()
644  *  o paging_init()
645  *  o dma_contiguous_reserve()
646  *
647  * At this stage the bootmem allocator is ready to use.
648  *
649  * NOTE: historically plat_mem_setup did the entire platform initialization.
650  *	 This was rather impractical because it meant plat_mem_setup had to
651  * get away without any kind of memory allocator.  To keep old code from
652  * breaking plat_setup was just renamed to plat_mem_setup and a second platform
653  * initialization hook for anything else was introduced.
654  */
655 
656 static int usermem __initdata;
657 
658 static int __init early_parse_mem(char *p)
659 {
660 	phys_addr_t start, size;
661 
662 	/*
663 	 * If a user specifies memory size, we
664 	 * blow away any automatically generated
665 	 * size.
666 	 */
667 	if (usermem == 0) {
668 		boot_mem_map.nr_map = 0;
669 		usermem = 1;
670 	}
671 	start = 0;
672 	size = memparse(p, &p);
673 	if (*p == '@')
674 		start = memparse(p + 1, &p);
675 
676 	add_memory_region(start, size, BOOT_MEM_RAM);
677 
678 	return 0;
679 }
680 early_param("mem", early_parse_mem);
681 
682 static int __init early_parse_memmap(char *p)
683 {
684 	char *oldp;
685 	u64 start_at, mem_size;
686 
687 	if (!p)
688 		return -EINVAL;
689 
690 	if (!strncmp(p, "exactmap", 8)) {
691 		pr_err("\"memmap=exactmap\" invalid on MIPS\n");
692 		return 0;
693 	}
694 
695 	oldp = p;
696 	mem_size = memparse(p, &p);
697 	if (p == oldp)
698 		return -EINVAL;
699 
700 	if (*p == '@') {
701 		start_at = memparse(p+1, &p);
702 		add_memory_region(start_at, mem_size, BOOT_MEM_RAM);
703 	} else if (*p == '#') {
704 		pr_err("\"memmap=nn#ss\" (force ACPI data) invalid on MIPS\n");
705 		return -EINVAL;
706 	} else if (*p == '$') {
707 		start_at = memparse(p+1, &p);
708 		add_memory_region(start_at, mem_size, BOOT_MEM_RESERVED);
709 	} else {
710 		pr_err("\"memmap\" invalid format!\n");
711 		return -EINVAL;
712 	}
713 
714 	if (*p == '\0') {
715 		usermem = 1;
716 		return 0;
717 	} else
718 		return -EINVAL;
719 }
720 early_param("memmap", early_parse_memmap);
721 
722 #ifdef CONFIG_PROC_VMCORE
723 unsigned long setup_elfcorehdr, setup_elfcorehdr_size;
724 static int __init early_parse_elfcorehdr(char *p)
725 {
726 	int i;
727 
728 	setup_elfcorehdr = memparse(p, &p);
729 
730 	for (i = 0; i < boot_mem_map.nr_map; i++) {
731 		unsigned long start = boot_mem_map.map[i].addr;
732 		unsigned long end = (boot_mem_map.map[i].addr +
733 				     boot_mem_map.map[i].size);
734 		if (setup_elfcorehdr >= start && setup_elfcorehdr < end) {
735 			/*
736 			 * Reserve from the elf core header to the end of
737 			 * the memory segment, that should all be kdump
738 			 * reserved memory.
739 			 */
740 			setup_elfcorehdr_size = end - setup_elfcorehdr;
741 			break;
742 		}
743 	}
744 	/*
745 	 * If we don't find it in the memory map, then we shouldn't
746 	 * have to worry about it, as the new kernel won't use it.
747 	 */
748 	return 0;
749 }
750 early_param("elfcorehdr", early_parse_elfcorehdr);
751 #endif
752 
753 static void __init arch_mem_addpart(phys_addr_t mem, phys_addr_t end, int type)
754 {
755 	phys_addr_t size;
756 	int i;
757 
758 	size = end - mem;
759 	if (!size)
760 		return;
761 
762 	/* Make sure it is in the boot_mem_map */
763 	for (i = 0; i < boot_mem_map.nr_map; i++) {
764 		if (mem >= boot_mem_map.map[i].addr &&
765 		    mem < (boot_mem_map.map[i].addr +
766 			   boot_mem_map.map[i].size))
767 			return;
768 	}
769 	add_memory_region(mem, size, type);
770 }
771 
772 #ifdef CONFIG_KEXEC
773 static inline unsigned long long get_total_mem(void)
774 {
775 	unsigned long long total;
776 
777 	total = max_pfn - min_low_pfn;
778 	return total << PAGE_SHIFT;
779 }
780 
781 static void __init mips_parse_crashkernel(void)
782 {
783 	unsigned long long total_mem;
784 	unsigned long long crash_size, crash_base;
785 	int ret;
786 
787 	total_mem = get_total_mem();
788 	ret = parse_crashkernel(boot_command_line, total_mem,
789 				&crash_size, &crash_base);
790 	if (ret != 0 || crash_size <= 0)
791 		return;
792 
793 	if (!memory_region_available(crash_base, crash_size)) {
794 		pr_warn("Invalid memory region reserved for crash kernel\n");
795 		return;
796 	}
797 
798 	crashk_res.start = crash_base;
799 	crashk_res.end	 = crash_base + crash_size - 1;
800 }
801 
802 static void __init request_crashkernel(struct resource *res)
803 {
804 	int ret;
805 
806 	if (crashk_res.start == crashk_res.end)
807 		return;
808 
809 	ret = request_resource(res, &crashk_res);
810 	if (!ret)
811 		pr_info("Reserving %ldMB of memory at %ldMB for crashkernel\n",
812 			(unsigned long)((crashk_res.end -
813 					 crashk_res.start + 1) >> 20),
814 			(unsigned long)(crashk_res.start  >> 20));
815 }
816 #else /* !defined(CONFIG_KEXEC)		*/
817 static void __init mips_parse_crashkernel(void)
818 {
819 }
820 
821 static void __init request_crashkernel(struct resource *res)
822 {
823 }
824 #endif /* !defined(CONFIG_KEXEC)  */
825 
826 #define USE_PROM_CMDLINE	IS_ENABLED(CONFIG_MIPS_CMDLINE_FROM_BOOTLOADER)
827 #define USE_DTB_CMDLINE		IS_ENABLED(CONFIG_MIPS_CMDLINE_FROM_DTB)
828 #define EXTEND_WITH_PROM	IS_ENABLED(CONFIG_MIPS_CMDLINE_DTB_EXTEND)
829 #define BUILTIN_EXTEND_WITH_PROM	\
830 	IS_ENABLED(CONFIG_MIPS_CMDLINE_BUILTIN_EXTEND)
831 
832 static void __init arch_mem_init(char **cmdline_p)
833 {
834 	struct memblock_region *reg;
835 	extern void plat_mem_setup(void);
836 
837 #if defined(CONFIG_CMDLINE_BOOL) && defined(CONFIG_CMDLINE_OVERRIDE)
838 	strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
839 #else
840 	if ((USE_PROM_CMDLINE && arcs_cmdline[0]) ||
841 	    (USE_DTB_CMDLINE && !boot_command_line[0]))
842 		strlcpy(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);
843 
844 	if (EXTEND_WITH_PROM && arcs_cmdline[0]) {
845 		if (boot_command_line[0])
846 			strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
847 		strlcat(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);
848 	}
849 
850 #if defined(CONFIG_CMDLINE_BOOL)
851 	if (builtin_cmdline[0]) {
852 		if (boot_command_line[0])
853 			strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
854 		strlcat(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
855 	}
856 
857 	if (BUILTIN_EXTEND_WITH_PROM && arcs_cmdline[0]) {
858 		if (boot_command_line[0])
859 			strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
860 		strlcat(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);
861 	}
862 #endif
863 #endif
864 
865 	/* call board setup routine */
866 	plat_mem_setup();
867 
868 	/*
869 	 * Make sure all kernel memory is in the maps.  The "UP" and
870 	 * "DOWN" are opposite for initdata since if it crosses over
871 	 * into another memory section you don't want that to be
872 	 * freed when the initdata is freed.
873 	 */
874 	arch_mem_addpart(PFN_DOWN(__pa_symbol(&_text)) << PAGE_SHIFT,
875 			 PFN_UP(__pa_symbol(&_edata)) << PAGE_SHIFT,
876 			 BOOT_MEM_RAM);
877 	arch_mem_addpart(PFN_UP(__pa_symbol(&__init_begin)) << PAGE_SHIFT,
878 			 PFN_DOWN(__pa_symbol(&__init_end)) << PAGE_SHIFT,
879 			 BOOT_MEM_INIT_RAM);
880 
881 	pr_info("Determined physical RAM map:\n");
882 	print_memory_map();
883 
884 	strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
885 
886 	*cmdline_p = command_line;
887 
888 	parse_early_param();
889 
890 	if (usermem) {
891 		pr_info("User-defined physical RAM map:\n");
892 		print_memory_map();
893 	}
894 
895 	early_init_fdt_reserve_self();
896 	early_init_fdt_scan_reserved_mem();
897 
898 	bootmem_init();
899 #ifdef CONFIG_PROC_VMCORE
900 	if (setup_elfcorehdr && setup_elfcorehdr_size) {
901 		printk(KERN_INFO "kdump reserved memory at %lx-%lx\n",
902 		       setup_elfcorehdr, setup_elfcorehdr_size);
903 		reserve_bootmem(setup_elfcorehdr, setup_elfcorehdr_size,
904 				BOOTMEM_DEFAULT);
905 	}
906 #endif
907 
908 	mips_parse_crashkernel();
909 #ifdef CONFIG_KEXEC
910 	if (crashk_res.start != crashk_res.end)
911 		reserve_bootmem(crashk_res.start,
912 				crashk_res.end - crashk_res.start + 1,
913 				BOOTMEM_DEFAULT);
914 #endif
915 	device_tree_init();
916 	sparse_init();
917 	plat_swiotlb_setup();
918 
919 	dma_contiguous_reserve(PFN_PHYS(max_low_pfn));
920 	/* Tell bootmem about cma reserved memblock section */
921 	for_each_memblock(reserved, reg)
922 		if (reg->size != 0)
923 			reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT);
924 
925 	reserve_bootmem_region(__pa_symbol(&__nosave_begin),
926 			__pa_symbol(&__nosave_end)); /* Reserve for hibernation */
927 }
928 
929 static void __init resource_init(void)
930 {
931 	int i;
932 
933 	if (UNCAC_BASE != IO_BASE)
934 		return;
935 
936 	code_resource.start = __pa_symbol(&_text);
937 	code_resource.end = __pa_symbol(&_etext) - 1;
938 	data_resource.start = __pa_symbol(&_etext);
939 	data_resource.end = __pa_symbol(&_edata) - 1;
940 	bss_resource.start = __pa_symbol(&__bss_start);
941 	bss_resource.end = __pa_symbol(&__bss_stop) - 1;
942 
943 	for (i = 0; i < boot_mem_map.nr_map; i++) {
944 		struct resource *res;
945 		unsigned long start, end;
946 
947 		start = boot_mem_map.map[i].addr;
948 		end = boot_mem_map.map[i].addr + boot_mem_map.map[i].size - 1;
949 		if (start >= HIGHMEM_START)
950 			continue;
951 		if (end >= HIGHMEM_START)
952 			end = HIGHMEM_START - 1;
953 
954 		res = alloc_bootmem(sizeof(struct resource));
955 
956 		res->start = start;
957 		res->end = end;
958 		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
959 
960 		switch (boot_mem_map.map[i].type) {
961 		case BOOT_MEM_RAM:
962 		case BOOT_MEM_INIT_RAM:
963 		case BOOT_MEM_ROM_DATA:
964 			res->name = "System RAM";
965 			res->flags |= IORESOURCE_SYSRAM;
966 			break;
967 		case BOOT_MEM_RESERVED:
968 		default:
969 			res->name = "reserved";
970 		}
971 
972 		request_resource(&iomem_resource, res);
973 
974 		/*
975 		 *  We don't know which RAM region contains kernel data,
976 		 *  so we try it repeatedly and let the resource manager
977 		 *  test it.
978 		 */
979 		request_resource(res, &code_resource);
980 		request_resource(res, &data_resource);
981 		request_resource(res, &bss_resource);
982 		request_crashkernel(res);
983 	}
984 }
985 
986 #ifdef CONFIG_SMP
987 static void __init prefill_possible_map(void)
988 {
989 	int i, possible = num_possible_cpus();
990 
991 	if (possible > nr_cpu_ids)
992 		possible = nr_cpu_ids;
993 
994 	for (i = 0; i < possible; i++)
995 		set_cpu_possible(i, true);
996 	for (; i < NR_CPUS; i++)
997 		set_cpu_possible(i, false);
998 
999 	nr_cpu_ids = possible;
1000 }
1001 #else
1002 static inline void prefill_possible_map(void) {}
1003 #endif
1004 
1005 void __init setup_arch(char **cmdline_p)
1006 {
1007 	cpu_probe();
1008 	mips_cm_probe();
1009 	prom_init();
1010 
1011 	setup_early_fdc_console();
1012 #ifdef CONFIG_EARLY_PRINTK
1013 	setup_early_printk();
1014 #endif
1015 	cpu_report();
1016 	check_bugs_early();
1017 
1018 #if defined(CONFIG_VT)
1019 #if defined(CONFIG_VGA_CONSOLE)
1020 	conswitchp = &vga_con;
1021 #elif defined(CONFIG_DUMMY_CONSOLE)
1022 	conswitchp = &dummy_con;
1023 #endif
1024 #endif
1025 
1026 	arch_mem_init(cmdline_p);
1027 
1028 	resource_init();
1029 	plat_smp_setup();
1030 	prefill_possible_map();
1031 
1032 	cpu_cache_init();
1033 	paging_init();
1034 }
1035 
1036 unsigned long kernelsp[NR_CPUS];
1037 unsigned long fw_arg0, fw_arg1, fw_arg2, fw_arg3;
1038 
1039 #ifdef CONFIG_USE_OF
1040 unsigned long fw_passed_dtb;
1041 #endif
1042 
1043 #ifdef CONFIG_DEBUG_FS
1044 struct dentry *mips_debugfs_dir;
1045 static int __init debugfs_mips(void)
1046 {
1047 	struct dentry *d;
1048 
1049 	d = debugfs_create_dir("mips", NULL);
1050 	if (!d)
1051 		return -ENOMEM;
1052 	mips_debugfs_dir = d;
1053 	return 0;
1054 }
1055 arch_initcall(debugfs_mips);
1056 #endif
1057