xref: /linux/arch/mips/kernel/setup.c (revision c4c14c3bd177ea769fee938674f73a8ec0cdd47a)
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/dma-coherence.h>
40 #include <asm/sections.h>
41 #include <asm/setup.h>
42 #include <asm/smp-ops.h>
43 #include <asm/prom.h>
44 
45 #ifdef CONFIG_MIPS_ELF_APPENDED_DTB
46 const char __section(.appended_dtb) __appended_dtb[0x100000];
47 #endif /* CONFIG_MIPS_ELF_APPENDED_DTB */
48 
49 struct cpuinfo_mips cpu_data[NR_CPUS] __read_mostly;
50 
51 EXPORT_SYMBOL(cpu_data);
52 
53 #ifdef CONFIG_VT
54 struct screen_info screen_info;
55 #endif
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 struct boot_mem_map boot_mem_map;
67 
68 static char __initdata command_line[COMMAND_LINE_SIZE];
69 char __initdata arcs_cmdline[COMMAND_LINE_SIZE];
70 
71 #ifdef CONFIG_CMDLINE_BOOL
72 static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
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 const 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 static void *detect_magic __initdata = detect_memory_region;
87 
88 #ifdef CONFIG_MIPS_AUTO_PFN_OFFSET
89 unsigned long ARCH_PFN_OFFSET;
90 EXPORT_SYMBOL(ARCH_PFN_OFFSET);
91 #endif
92 
93 void __init add_memory_region(phys_addr_t start, phys_addr_t size, long type)
94 {
95 	int x = boot_mem_map.nr_map;
96 	int i;
97 
98 	/*
99 	 * If the region reaches the top of the physical address space, adjust
100 	 * the size slightly so that (start + size) doesn't overflow
101 	 */
102 	if (start + size - 1 == PHYS_ADDR_MAX)
103 		--size;
104 
105 	/* Sanity check */
106 	if (start + size < start) {
107 		pr_warn("Trying to add an invalid memory region, skipped\n");
108 		return;
109 	}
110 
111 	/*
112 	 * Try to merge with existing entry, if any.
113 	 */
114 	for (i = 0; i < boot_mem_map.nr_map; i++) {
115 		struct boot_mem_map_entry *entry = boot_mem_map.map + i;
116 		unsigned long top;
117 
118 		if (entry->type != type)
119 			continue;
120 
121 		if (start + size < entry->addr)
122 			continue;			/* no overlap */
123 
124 		if (entry->addr + entry->size < start)
125 			continue;			/* no overlap */
126 
127 		top = max(entry->addr + entry->size, start + size);
128 		entry->addr = min(entry->addr, start);
129 		entry->size = top - entry->addr;
130 
131 		return;
132 	}
133 
134 	if (boot_mem_map.nr_map == BOOT_MEM_MAP_MAX) {
135 		pr_err("Ooops! Too many entries in the memory map!\n");
136 		return;
137 	}
138 
139 	boot_mem_map.map[x].addr = start;
140 	boot_mem_map.map[x].size = size;
141 	boot_mem_map.map[x].type = type;
142 	boot_mem_map.nr_map++;
143 }
144 
145 void __init detect_memory_region(phys_addr_t start, phys_addr_t sz_min, phys_addr_t sz_max)
146 {
147 	void *dm = &detect_magic;
148 	phys_addr_t size;
149 
150 	for (size = sz_min; size < sz_max; size <<= 1) {
151 		if (!memcmp(dm, dm + size, sizeof(detect_magic)))
152 			break;
153 	}
154 
155 	pr_debug("Memory: %lluMB of RAM detected at 0x%llx (min: %lluMB, max: %lluMB)\n",
156 		((unsigned long long) size) / SZ_1M,
157 		(unsigned long long) start,
158 		((unsigned long long) sz_min) / SZ_1M,
159 		((unsigned long long) sz_max) / SZ_1M);
160 
161 	add_memory_region(start, size, BOOT_MEM_RAM);
162 }
163 
164 static bool __init __maybe_unused memory_region_available(phys_addr_t start,
165 							  phys_addr_t size)
166 {
167 	int i;
168 	bool in_ram = false, free = true;
169 
170 	for (i = 0; i < boot_mem_map.nr_map; i++) {
171 		phys_addr_t start_, end_;
172 
173 		start_ = boot_mem_map.map[i].addr;
174 		end_ = boot_mem_map.map[i].addr + boot_mem_map.map[i].size;
175 
176 		switch (boot_mem_map.map[i].type) {
177 		case BOOT_MEM_RAM:
178 			if (start >= start_ && start + size <= end_)
179 				in_ram = true;
180 			break;
181 		case BOOT_MEM_RESERVED:
182 			if ((start >= start_ && start < end_) ||
183 			    (start < start_ && start + size >= start_))
184 				free = false;
185 			break;
186 		default:
187 			continue;
188 		}
189 	}
190 
191 	return in_ram && free;
192 }
193 
194 static void __init print_memory_map(void)
195 {
196 	int i;
197 	const int field = 2 * sizeof(unsigned long);
198 
199 	for (i = 0; i < boot_mem_map.nr_map; i++) {
200 		printk(KERN_INFO " memory: %0*Lx @ %0*Lx ",
201 		       field, (unsigned long long) boot_mem_map.map[i].size,
202 		       field, (unsigned long long) boot_mem_map.map[i].addr);
203 
204 		switch (boot_mem_map.map[i].type) {
205 		case BOOT_MEM_RAM:
206 			printk(KERN_CONT "(usable)\n");
207 			break;
208 		case BOOT_MEM_INIT_RAM:
209 			printk(KERN_CONT "(usable after init)\n");
210 			break;
211 		case BOOT_MEM_ROM_DATA:
212 			printk(KERN_CONT "(ROM data)\n");
213 			break;
214 		case BOOT_MEM_RESERVED:
215 			printk(KERN_CONT "(reserved)\n");
216 			break;
217 		default:
218 			printk(KERN_CONT "type %lu\n", boot_mem_map.map[i].type);
219 			break;
220 		}
221 	}
222 }
223 
224 /*
225  * Manage initrd
226  */
227 #ifdef CONFIG_BLK_DEV_INITRD
228 
229 static int __init rd_start_early(char *p)
230 {
231 	unsigned long start = memparse(p, &p);
232 
233 #ifdef CONFIG_64BIT
234 	/* Guess if the sign extension was forgotten by bootloader */
235 	if (start < XKPHYS)
236 		start = (int)start;
237 #endif
238 	initrd_start = start;
239 	initrd_end += start;
240 	return 0;
241 }
242 early_param("rd_start", rd_start_early);
243 
244 static int __init rd_size_early(char *p)
245 {
246 	initrd_end += memparse(p, &p);
247 	return 0;
248 }
249 early_param("rd_size", rd_size_early);
250 
251 /* it returns the next free pfn after initrd */
252 static unsigned long __init init_initrd(void)
253 {
254 	unsigned long end;
255 
256 	/*
257 	 * Board specific code or command line parser should have
258 	 * already set up initrd_start and initrd_end. In these cases
259 	 * perfom sanity checks and use them if all looks good.
260 	 */
261 	if (!initrd_start || initrd_end <= initrd_start)
262 		goto disable;
263 
264 	if (initrd_start & ~PAGE_MASK) {
265 		pr_err("initrd start must be page aligned\n");
266 		goto disable;
267 	}
268 	if (initrd_start < PAGE_OFFSET) {
269 		pr_err("initrd start < PAGE_OFFSET\n");
270 		goto disable;
271 	}
272 
273 	/*
274 	 * Sanitize initrd addresses. For example firmware
275 	 * can't guess if they need to pass them through
276 	 * 64-bits values if the kernel has been built in pure
277 	 * 32-bit. We need also to switch from KSEG0 to XKPHYS
278 	 * addresses now, so the code can now safely use __pa().
279 	 */
280 	end = __pa(initrd_end);
281 	initrd_end = (unsigned long)__va(end);
282 	initrd_start = (unsigned long)__va(__pa(initrd_start));
283 
284 	ROOT_DEV = Root_RAM0;
285 	return PFN_UP(end);
286 disable:
287 	initrd_start = 0;
288 	initrd_end = 0;
289 	return 0;
290 }
291 
292 /* In some conditions (e.g. big endian bootloader with a little endian
293    kernel), the initrd might appear byte swapped.  Try to detect this and
294    byte swap it if needed.  */
295 static void __init maybe_bswap_initrd(void)
296 {
297 #if defined(CONFIG_CPU_CAVIUM_OCTEON)
298 	u64 buf;
299 
300 	/* Check for CPIO signature */
301 	if (!memcmp((void *)initrd_start, "070701", 6))
302 		return;
303 
304 	/* Check for compressed initrd */
305 	if (decompress_method((unsigned char *)initrd_start, 8, NULL))
306 		return;
307 
308 	/* Try again with a byte swapped header */
309 	buf = swab64p((u64 *)initrd_start);
310 	if (!memcmp(&buf, "070701", 6) ||
311 	    decompress_method((unsigned char *)(&buf), 8, NULL)) {
312 		unsigned long i;
313 
314 		pr_info("Byteswapped initrd detected\n");
315 		for (i = initrd_start; i < ALIGN(initrd_end, 8); i += 8)
316 			swab64s((u64 *)i);
317 	}
318 #endif
319 }
320 
321 static void __init finalize_initrd(void)
322 {
323 	unsigned long size = initrd_end - initrd_start;
324 
325 	if (size == 0) {
326 		printk(KERN_INFO "Initrd not found or empty");
327 		goto disable;
328 	}
329 	if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
330 		printk(KERN_ERR "Initrd extends beyond end of memory");
331 		goto disable;
332 	}
333 
334 	maybe_bswap_initrd();
335 
336 	memblock_reserve(__pa(initrd_start), size);
337 	initrd_below_start_ok = 1;
338 
339 	pr_info("Initial ramdisk at: 0x%lx (%lu bytes)\n",
340 		initrd_start, size);
341 	return;
342 disable:
343 	printk(KERN_CONT " - disabling initrd\n");
344 	initrd_start = 0;
345 	initrd_end = 0;
346 }
347 
348 #else  /* !CONFIG_BLK_DEV_INITRD */
349 
350 static unsigned long __init init_initrd(void)
351 {
352 	return 0;
353 }
354 
355 #define finalize_initrd()	do {} while (0)
356 
357 #endif
358 
359 /*
360  * Initialize the bootmem allocator. It also setup initrd related data
361  * if needed.
362  */
363 #if defined(CONFIG_SGI_IP27) || (defined(CONFIG_CPU_LOONGSON3) && defined(CONFIG_NUMA))
364 
365 static void __init bootmem_init(void)
366 {
367 	init_initrd();
368 	finalize_initrd();
369 }
370 
371 #else  /* !CONFIG_SGI_IP27 */
372 
373 static void __init bootmem_init(void)
374 {
375 	unsigned long reserved_end;
376 	phys_addr_t ramstart = PHYS_ADDR_MAX;
377 	int i;
378 
379 	/*
380 	 * Sanity check any INITRD first. We don't take it into account
381 	 * for bootmem setup initially, rely on the end-of-kernel-code
382 	 * as our memory range starting point. Once bootmem is inited we
383 	 * will reserve the area used for the initrd.
384 	 */
385 	init_initrd();
386 	reserved_end = (unsigned long) PFN_UP(__pa_symbol(&_end));
387 
388 	memblock_reserve(PHYS_OFFSET, reserved_end << PAGE_SHIFT);
389 
390 	/*
391 	 * max_low_pfn is not a number of pages. The number of pages
392 	 * of the system is given by 'max_low_pfn - min_low_pfn'.
393 	 */
394 	min_low_pfn = ~0UL;
395 	max_low_pfn = 0;
396 
397 	/*
398 	 * Find the highest page frame number we have available
399 	 * and the lowest used RAM address
400 	 */
401 	for (i = 0; i < boot_mem_map.nr_map; i++) {
402 		unsigned long start, end;
403 
404 		if (boot_mem_map.map[i].type != BOOT_MEM_RAM)
405 			continue;
406 
407 		start = PFN_UP(boot_mem_map.map[i].addr);
408 		end = PFN_DOWN(boot_mem_map.map[i].addr
409 				+ boot_mem_map.map[i].size);
410 
411 		ramstart = min(ramstart, boot_mem_map.map[i].addr);
412 
413 #ifndef CONFIG_HIGHMEM
414 		/*
415 		 * Skip highmem here so we get an accurate max_low_pfn if low
416 		 * memory stops short of high memory.
417 		 * If the region overlaps HIGHMEM_START, end is clipped so
418 		 * max_pfn excludes the highmem portion.
419 		 */
420 		if (start >= PFN_DOWN(HIGHMEM_START))
421 			continue;
422 		if (end > PFN_DOWN(HIGHMEM_START))
423 			end = PFN_DOWN(HIGHMEM_START);
424 #endif
425 
426 		if (end > max_low_pfn)
427 			max_low_pfn = end;
428 		if (start < min_low_pfn)
429 			min_low_pfn = start;
430 		if (end <= reserved_end)
431 			continue;
432 #ifdef CONFIG_BLK_DEV_INITRD
433 		/* Skip zones before initrd and initrd itself */
434 		if (initrd_end && end <= (unsigned long)PFN_UP(__pa(initrd_end)))
435 			continue;
436 #endif
437 	}
438 
439 	if (min_low_pfn >= max_low_pfn)
440 		panic("Incorrect memory mapping !!!");
441 
442 #ifdef CONFIG_MIPS_AUTO_PFN_OFFSET
443 	ARCH_PFN_OFFSET = PFN_UP(ramstart);
444 #else
445 	/*
446 	 * Reserve any memory between the start of RAM and PHYS_OFFSET
447 	 */
448 	if (ramstart > PHYS_OFFSET) {
449 		add_memory_region(PHYS_OFFSET, ramstart - PHYS_OFFSET,
450 				  BOOT_MEM_RESERVED);
451 		memblock_reserve(PHYS_OFFSET, ramstart - PHYS_OFFSET);
452 	}
453 
454 	if (min_low_pfn > ARCH_PFN_OFFSET) {
455 		pr_info("Wasting %lu bytes for tracking %lu unused pages\n",
456 			(min_low_pfn - ARCH_PFN_OFFSET) * sizeof(struct page),
457 			min_low_pfn - ARCH_PFN_OFFSET);
458 	} else if (ARCH_PFN_OFFSET - min_low_pfn > 0UL) {
459 		pr_info("%lu free pages won't be used\n",
460 			ARCH_PFN_OFFSET - min_low_pfn);
461 	}
462 	min_low_pfn = ARCH_PFN_OFFSET;
463 #endif
464 
465 	/*
466 	 * Determine low and high memory ranges
467 	 */
468 	max_pfn = max_low_pfn;
469 	if (max_low_pfn > PFN_DOWN(HIGHMEM_START)) {
470 #ifdef CONFIG_HIGHMEM
471 		highstart_pfn = PFN_DOWN(HIGHMEM_START);
472 		highend_pfn = max_low_pfn;
473 #endif
474 		max_low_pfn = PFN_DOWN(HIGHMEM_START);
475 	}
476 
477 	for (i = 0; i < boot_mem_map.nr_map; i++) {
478 		unsigned long start, end;
479 
480 		start = PFN_UP(boot_mem_map.map[i].addr);
481 		end = PFN_DOWN(boot_mem_map.map[i].addr
482 				+ boot_mem_map.map[i].size);
483 
484 		if (start <= min_low_pfn)
485 			start = min_low_pfn;
486 		if (start >= end)
487 			continue;
488 
489 #ifndef CONFIG_HIGHMEM
490 		if (end > max_low_pfn)
491 			end = max_low_pfn;
492 
493 		/*
494 		 * ... finally, is the area going away?
495 		 */
496 		if (end <= start)
497 			continue;
498 #endif
499 
500 		memblock_add_node(PFN_PHYS(start), PFN_PHYS(end - start), 0);
501 	}
502 
503 	/*
504 	 * Register fully available low RAM pages with the bootmem allocator.
505 	 */
506 	for (i = 0; i < boot_mem_map.nr_map; i++) {
507 		unsigned long start, end, size;
508 
509 		start = PFN_UP(boot_mem_map.map[i].addr);
510 		end   = PFN_DOWN(boot_mem_map.map[i].addr
511 				    + boot_mem_map.map[i].size);
512 
513 		/*
514 		 * Reserve usable memory.
515 		 */
516 		switch (boot_mem_map.map[i].type) {
517 		case BOOT_MEM_RAM:
518 			break;
519 		case BOOT_MEM_INIT_RAM:
520 			memory_present(0, start, end);
521 			continue;
522 		default:
523 			/* Not usable memory */
524 			if (start > min_low_pfn && end < max_low_pfn)
525 				memblock_reserve(boot_mem_map.map[i].addr,
526 						boot_mem_map.map[i].size);
527 
528 			continue;
529 		}
530 
531 		/*
532 		 * We are rounding up the start address of usable memory
533 		 * and at the end of the usable range downwards.
534 		 */
535 		if (start >= max_low_pfn)
536 			continue;
537 		if (start < reserved_end)
538 			start = reserved_end;
539 		if (end > max_low_pfn)
540 			end = max_low_pfn;
541 
542 		/*
543 		 * ... finally, is the area going away?
544 		 */
545 		if (end <= start)
546 			continue;
547 		size = end - start;
548 
549 		/* Register lowmem ranges */
550 		memory_present(0, start, end);
551 	}
552 
553 #ifdef CONFIG_RELOCATABLE
554 	/*
555 	 * The kernel reserves all memory below its _end symbol as bootmem,
556 	 * but the kernel may now be at a much higher address. The memory
557 	 * between the original and new locations may be returned to the system.
558 	 */
559 	if (__pa_symbol(_text) > __pa_symbol(VMLINUX_LOAD_ADDRESS)) {
560 		unsigned long offset;
561 		extern void show_kernel_relocation(const char *level);
562 
563 		offset = __pa_symbol(_text) - __pa_symbol(VMLINUX_LOAD_ADDRESS);
564 		free_bootmem(__pa_symbol(VMLINUX_LOAD_ADDRESS), offset);
565 
566 #if defined(CONFIG_DEBUG_KERNEL) && defined(CONFIG_DEBUG_INFO)
567 		/*
568 		 * This information is necessary when debugging the kernel
569 		 * But is a security vulnerability otherwise!
570 		 */
571 		show_kernel_relocation(KERN_INFO);
572 #endif
573 	}
574 #endif
575 
576 	/*
577 	 * Reserve initrd memory if needed.
578 	 */
579 	finalize_initrd();
580 }
581 
582 #endif	/* CONFIG_SGI_IP27 */
583 
584 static int usermem __initdata;
585 
586 static int __init early_parse_mem(char *p)
587 {
588 	phys_addr_t start, size;
589 
590 	/*
591 	 * If a user specifies memory size, we
592 	 * blow away any automatically generated
593 	 * size.
594 	 */
595 	if (usermem == 0) {
596 		boot_mem_map.nr_map = 0;
597 		usermem = 1;
598 	}
599 	start = 0;
600 	size = memparse(p, &p);
601 	if (*p == '@')
602 		start = memparse(p + 1, &p);
603 
604 	add_memory_region(start, size, BOOT_MEM_RAM);
605 
606 	return 0;
607 }
608 early_param("mem", early_parse_mem);
609 
610 static int __init early_parse_memmap(char *p)
611 {
612 	char *oldp;
613 	u64 start_at, mem_size;
614 
615 	if (!p)
616 		return -EINVAL;
617 
618 	if (!strncmp(p, "exactmap", 8)) {
619 		pr_err("\"memmap=exactmap\" invalid on MIPS\n");
620 		return 0;
621 	}
622 
623 	oldp = p;
624 	mem_size = memparse(p, &p);
625 	if (p == oldp)
626 		return -EINVAL;
627 
628 	if (*p == '@') {
629 		start_at = memparse(p+1, &p);
630 		add_memory_region(start_at, mem_size, BOOT_MEM_RAM);
631 	} else if (*p == '#') {
632 		pr_err("\"memmap=nn#ss\" (force ACPI data) invalid on MIPS\n");
633 		return -EINVAL;
634 	} else if (*p == '$') {
635 		start_at = memparse(p+1, &p);
636 		add_memory_region(start_at, mem_size, BOOT_MEM_RESERVED);
637 	} else {
638 		pr_err("\"memmap\" invalid format!\n");
639 		return -EINVAL;
640 	}
641 
642 	if (*p == '\0') {
643 		usermem = 1;
644 		return 0;
645 	} else
646 		return -EINVAL;
647 }
648 early_param("memmap", early_parse_memmap);
649 
650 #ifdef CONFIG_PROC_VMCORE
651 unsigned long setup_elfcorehdr, setup_elfcorehdr_size;
652 static int __init early_parse_elfcorehdr(char *p)
653 {
654 	int i;
655 
656 	setup_elfcorehdr = memparse(p, &p);
657 
658 	for (i = 0; i < boot_mem_map.nr_map; i++) {
659 		unsigned long start = boot_mem_map.map[i].addr;
660 		unsigned long end = (boot_mem_map.map[i].addr +
661 				     boot_mem_map.map[i].size);
662 		if (setup_elfcorehdr >= start && setup_elfcorehdr < end) {
663 			/*
664 			 * Reserve from the elf core header to the end of
665 			 * the memory segment, that should all be kdump
666 			 * reserved memory.
667 			 */
668 			setup_elfcorehdr_size = end - setup_elfcorehdr;
669 			break;
670 		}
671 	}
672 	/*
673 	 * If we don't find it in the memory map, then we shouldn't
674 	 * have to worry about it, as the new kernel won't use it.
675 	 */
676 	return 0;
677 }
678 early_param("elfcorehdr", early_parse_elfcorehdr);
679 #endif
680 
681 static void __init arch_mem_addpart(phys_addr_t mem, phys_addr_t end, int type)
682 {
683 	phys_addr_t size;
684 	int i;
685 
686 	size = end - mem;
687 	if (!size)
688 		return;
689 
690 	/* Make sure it is in the boot_mem_map */
691 	for (i = 0; i < boot_mem_map.nr_map; i++) {
692 		if (mem >= boot_mem_map.map[i].addr &&
693 		    mem < (boot_mem_map.map[i].addr +
694 			   boot_mem_map.map[i].size))
695 			return;
696 	}
697 	add_memory_region(mem, size, type);
698 }
699 
700 #ifdef CONFIG_KEXEC
701 static inline unsigned long long get_total_mem(void)
702 {
703 	unsigned long long total;
704 
705 	total = max_pfn - min_low_pfn;
706 	return total << PAGE_SHIFT;
707 }
708 
709 static void __init mips_parse_crashkernel(void)
710 {
711 	unsigned long long total_mem;
712 	unsigned long long crash_size, crash_base;
713 	int ret;
714 
715 	total_mem = get_total_mem();
716 	ret = parse_crashkernel(boot_command_line, total_mem,
717 				&crash_size, &crash_base);
718 	if (ret != 0 || crash_size <= 0)
719 		return;
720 
721 	if (!memory_region_available(crash_base, crash_size)) {
722 		pr_warn("Invalid memory region reserved for crash kernel\n");
723 		return;
724 	}
725 
726 	crashk_res.start = crash_base;
727 	crashk_res.end	 = crash_base + crash_size - 1;
728 }
729 
730 static void __init request_crashkernel(struct resource *res)
731 {
732 	int ret;
733 
734 	if (crashk_res.start == crashk_res.end)
735 		return;
736 
737 	ret = request_resource(res, &crashk_res);
738 	if (!ret)
739 		pr_info("Reserving %ldMB of memory at %ldMB for crashkernel\n",
740 			(unsigned long)((crashk_res.end -
741 					 crashk_res.start + 1) >> 20),
742 			(unsigned long)(crashk_res.start  >> 20));
743 }
744 #else /* !defined(CONFIG_KEXEC)		*/
745 static void __init mips_parse_crashkernel(void)
746 {
747 }
748 
749 static void __init request_crashkernel(struct resource *res)
750 {
751 }
752 #endif /* !defined(CONFIG_KEXEC)  */
753 
754 #define USE_PROM_CMDLINE	IS_ENABLED(CONFIG_MIPS_CMDLINE_FROM_BOOTLOADER)
755 #define USE_DTB_CMDLINE		IS_ENABLED(CONFIG_MIPS_CMDLINE_FROM_DTB)
756 #define EXTEND_WITH_PROM	IS_ENABLED(CONFIG_MIPS_CMDLINE_DTB_EXTEND)
757 #define BUILTIN_EXTEND_WITH_PROM	\
758 	IS_ENABLED(CONFIG_MIPS_CMDLINE_BUILTIN_EXTEND)
759 
760 /*
761  * arch_mem_init - initialize memory management subsystem
762  *
763  *  o plat_mem_setup() detects the memory configuration and will record detected
764  *    memory areas using add_memory_region.
765  *
766  * At this stage the memory configuration of the system is known to the
767  * kernel but generic memory management system is still entirely uninitialized.
768  *
769  *  o bootmem_init()
770  *  o sparse_init()
771  *  o paging_init()
772  *  o dma_contiguous_reserve()
773  *
774  * At this stage the bootmem allocator is ready to use.
775  *
776  * NOTE: historically plat_mem_setup did the entire platform initialization.
777  *	 This was rather impractical because it meant plat_mem_setup had to
778  * get away without any kind of memory allocator.  To keep old code from
779  * breaking plat_setup was just renamed to plat_mem_setup and a second platform
780  * initialization hook for anything else was introduced.
781  */
782 static void __init arch_mem_init(char **cmdline_p)
783 {
784 	struct memblock_region *reg;
785 	extern void plat_mem_setup(void);
786 
787 	/*
788 	 * Initialize boot_command_line to an innocuous but non-empty string in
789 	 * order to prevent early_init_dt_scan_chosen() from copying
790 	 * CONFIG_CMDLINE into it without our knowledge. We handle
791 	 * CONFIG_CMDLINE ourselves below & don't want to duplicate its
792 	 * content because repeating arguments can be problematic.
793 	 */
794 	strlcpy(boot_command_line, " ", COMMAND_LINE_SIZE);
795 
796 	/* call board setup routine */
797 	plat_mem_setup();
798 
799 	/*
800 	 * Make sure all kernel memory is in the maps.  The "UP" and
801 	 * "DOWN" are opposite for initdata since if it crosses over
802 	 * into another memory section you don't want that to be
803 	 * freed when the initdata is freed.
804 	 */
805 	arch_mem_addpart(PFN_DOWN(__pa_symbol(&_text)) << PAGE_SHIFT,
806 			 PFN_UP(__pa_symbol(&_edata)) << PAGE_SHIFT,
807 			 BOOT_MEM_RAM);
808 	arch_mem_addpart(PFN_UP(__pa_symbol(&__init_begin)) << PAGE_SHIFT,
809 			 PFN_DOWN(__pa_symbol(&__init_end)) << PAGE_SHIFT,
810 			 BOOT_MEM_INIT_RAM);
811 
812 	pr_info("Determined physical RAM map:\n");
813 	print_memory_map();
814 
815 #if defined(CONFIG_CMDLINE_BOOL) && defined(CONFIG_CMDLINE_OVERRIDE)
816 	strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
817 #else
818 	if ((USE_PROM_CMDLINE && arcs_cmdline[0]) ||
819 	    (USE_DTB_CMDLINE && !boot_command_line[0]))
820 		strlcpy(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);
821 
822 	if (EXTEND_WITH_PROM && arcs_cmdline[0]) {
823 		if (boot_command_line[0])
824 			strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
825 		strlcat(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);
826 	}
827 
828 #if defined(CONFIG_CMDLINE_BOOL)
829 	if (builtin_cmdline[0]) {
830 		if (boot_command_line[0])
831 			strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
832 		strlcat(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
833 	}
834 
835 	if (BUILTIN_EXTEND_WITH_PROM && arcs_cmdline[0]) {
836 		if (boot_command_line[0])
837 			strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
838 		strlcat(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);
839 	}
840 #endif
841 #endif
842 	strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
843 
844 	*cmdline_p = command_line;
845 
846 	parse_early_param();
847 
848 	if (usermem) {
849 		pr_info("User-defined physical RAM map:\n");
850 		print_memory_map();
851 	}
852 
853 	early_init_fdt_reserve_self();
854 	early_init_fdt_scan_reserved_mem();
855 
856 	bootmem_init();
857 
858 	/*
859 	 * Prevent memblock from allocating high memory.
860 	 * This cannot be done before max_low_pfn is detected, so up
861 	 * to this point is possible to only reserve physical memory
862 	 * with memblock_reserve; memblock_virt_alloc* can be used
863 	 * only after this point
864 	 */
865 	memblock_set_current_limit(PFN_PHYS(max_low_pfn));
866 
867 #ifdef CONFIG_PROC_VMCORE
868 	if (setup_elfcorehdr && setup_elfcorehdr_size) {
869 		printk(KERN_INFO "kdump reserved memory at %lx-%lx\n",
870 		       setup_elfcorehdr, setup_elfcorehdr_size);
871 		memblock_reserve(setup_elfcorehdr, setup_elfcorehdr_size);
872 	}
873 #endif
874 
875 	mips_parse_crashkernel();
876 #ifdef CONFIG_KEXEC
877 	if (crashk_res.start != crashk_res.end)
878 		memblock_reserve(crashk_res.start,
879 				 crashk_res.end - crashk_res.start + 1);
880 #endif
881 	device_tree_init();
882 	sparse_init();
883 	plat_swiotlb_setup();
884 
885 	dma_contiguous_reserve(PFN_PHYS(max_low_pfn));
886 	/* Tell bootmem about cma reserved memblock section */
887 	for_each_memblock(reserved, reg)
888 		if (reg->size != 0)
889 			memblock_reserve(reg->base, reg->size);
890 
891 	reserve_bootmem_region(__pa_symbol(&__nosave_begin),
892 			__pa_symbol(&__nosave_end)); /* Reserve for hibernation */
893 }
894 
895 static void __init resource_init(void)
896 {
897 	int i;
898 
899 	if (UNCAC_BASE != IO_BASE)
900 		return;
901 
902 	code_resource.start = __pa_symbol(&_text);
903 	code_resource.end = __pa_symbol(&_etext) - 1;
904 	data_resource.start = __pa_symbol(&_etext);
905 	data_resource.end = __pa_symbol(&_edata) - 1;
906 	bss_resource.start = __pa_symbol(&__bss_start);
907 	bss_resource.end = __pa_symbol(&__bss_stop) - 1;
908 
909 	for (i = 0; i < boot_mem_map.nr_map; i++) {
910 		struct resource *res;
911 		unsigned long start, end;
912 
913 		start = boot_mem_map.map[i].addr;
914 		end = boot_mem_map.map[i].addr + boot_mem_map.map[i].size - 1;
915 		if (start >= HIGHMEM_START)
916 			continue;
917 		if (end >= HIGHMEM_START)
918 			end = HIGHMEM_START - 1;
919 
920 		res = alloc_bootmem(sizeof(struct resource));
921 
922 		res->start = start;
923 		res->end = end;
924 		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
925 
926 		switch (boot_mem_map.map[i].type) {
927 		case BOOT_MEM_RAM:
928 		case BOOT_MEM_INIT_RAM:
929 		case BOOT_MEM_ROM_DATA:
930 			res->name = "System RAM";
931 			res->flags |= IORESOURCE_SYSRAM;
932 			break;
933 		case BOOT_MEM_RESERVED:
934 		default:
935 			res->name = "reserved";
936 		}
937 
938 		request_resource(&iomem_resource, res);
939 
940 		/*
941 		 *  We don't know which RAM region contains kernel data,
942 		 *  so we try it repeatedly and let the resource manager
943 		 *  test it.
944 		 */
945 		request_resource(res, &code_resource);
946 		request_resource(res, &data_resource);
947 		request_resource(res, &bss_resource);
948 		request_crashkernel(res);
949 	}
950 }
951 
952 #ifdef CONFIG_SMP
953 static void __init prefill_possible_map(void)
954 {
955 	int i, possible = num_possible_cpus();
956 
957 	if (possible > nr_cpu_ids)
958 		possible = nr_cpu_ids;
959 
960 	for (i = 0; i < possible; i++)
961 		set_cpu_possible(i, true);
962 	for (; i < NR_CPUS; i++)
963 		set_cpu_possible(i, false);
964 
965 	nr_cpu_ids = possible;
966 }
967 #else
968 static inline void prefill_possible_map(void) {}
969 #endif
970 
971 void __init setup_arch(char **cmdline_p)
972 {
973 	cpu_probe();
974 	mips_cm_probe();
975 	prom_init();
976 
977 	setup_early_fdc_console();
978 #ifdef CONFIG_EARLY_PRINTK
979 	setup_early_printk();
980 #endif
981 	cpu_report();
982 	check_bugs_early();
983 
984 #if defined(CONFIG_VT)
985 #if defined(CONFIG_VGA_CONSOLE)
986 	conswitchp = &vga_con;
987 #elif defined(CONFIG_DUMMY_CONSOLE)
988 	conswitchp = &dummy_con;
989 #endif
990 #endif
991 
992 	arch_mem_init(cmdline_p);
993 
994 	resource_init();
995 	plat_smp_setup();
996 	prefill_possible_map();
997 
998 	cpu_cache_init();
999 	paging_init();
1000 }
1001 
1002 unsigned long kernelsp[NR_CPUS];
1003 unsigned long fw_arg0, fw_arg1, fw_arg2, fw_arg3;
1004 
1005 #ifdef CONFIG_USE_OF
1006 unsigned long fw_passed_dtb;
1007 #endif
1008 
1009 #ifdef CONFIG_DEBUG_FS
1010 struct dentry *mips_debugfs_dir;
1011 static int __init debugfs_mips(void)
1012 {
1013 	struct dentry *d;
1014 
1015 	d = debugfs_create_dir("mips", NULL);
1016 	if (!d)
1017 		return -ENOMEM;
1018 	mips_debugfs_dir = d;
1019 	return 0;
1020 }
1021 arch_initcall(debugfs_mips);
1022 #endif
1023 
1024 #ifdef CONFIG_DMA_MAYBE_COHERENT
1025 /* User defined DMA coherency from command line. */
1026 enum coherent_io_user_state coherentio = IO_COHERENCE_DEFAULT;
1027 EXPORT_SYMBOL_GPL(coherentio);
1028 int hw_coherentio = 0;	/* Actual hardware supported DMA coherency setting. */
1029 
1030 static int __init setcoherentio(char *str)
1031 {
1032 	coherentio = IO_COHERENCE_ENABLED;
1033 	pr_info("Hardware DMA cache coherency (command line)\n");
1034 	return 0;
1035 }
1036 early_param("coherentio", setcoherentio);
1037 
1038 static int __init setnocoherentio(char *str)
1039 {
1040 	coherentio = IO_COHERENCE_DISABLED;
1041 	pr_info("Software DMA cache coherency (command line)\n");
1042 	return 0;
1043 }
1044 early_param("nocoherentio", setnocoherentio);
1045 #endif
1046