xref: /openbmc/linux/arch/mips/kernel/setup.c (revision 55eb9a6c)
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/initrd.h>
19 #include <linux/root_dev.h>
20 #include <linux/highmem.h>
21 #include <linux/console.h>
22 #include <linux/pfn.h>
23 #include <linux/debugfs.h>
24 #include <linux/kexec.h>
25 #include <linux/sizes.h>
26 #include <linux/device.h>
27 #include <linux/dma-map-ops.h>
28 #include <linux/decompress/generic.h>
29 #include <linux/of_fdt.h>
30 #include <linux/dmi.h>
31 #include <linux/crash_dump.h>
32 
33 #include <asm/addrspace.h>
34 #include <asm/bootinfo.h>
35 #include <asm/bugs.h>
36 #include <asm/cache.h>
37 #include <asm/cdmm.h>
38 #include <asm/cpu.h>
39 #include <asm/debug.h>
40 #include <asm/mmzone.h>
41 #include <asm/sections.h>
42 #include <asm/setup.h>
43 #include <asm/smp-ops.h>
44 #include <asm/prom.h>
45 
46 #ifdef CONFIG_MIPS_ELF_APPENDED_DTB
47 char __section(".appended_dtb") __appended_dtb[0x100000];
48 #endif /* CONFIG_MIPS_ELF_APPENDED_DTB */
49 
50 struct cpuinfo_mips cpu_data[NR_CPUS] __read_mostly;
51 
52 EXPORT_SYMBOL(cpu_data);
53 
54 #ifdef CONFIG_VT
55 struct screen_info screen_info;
56 #endif
57 
58 /*
59  * Setup information
60  *
61  * These are initialized so they are in the .data section
62  */
63 unsigned long mips_machtype __read_mostly = MACH_UNKNOWN;
64 
65 EXPORT_SYMBOL(mips_machtype);
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 const char builtin_cmdline[] __initconst = CONFIG_CMDLINE;
72 #else
73 static const char builtin_cmdline[] __initconst = "";
74 #endif
75 
76 /*
77  * mips_io_port_base is the begin of the address space to which x86 style
78  * I/O ports are mapped.
79  */
80 unsigned long mips_io_port_base = -1;
81 EXPORT_SYMBOL(mips_io_port_base);
82 
83 static struct resource code_resource = { .name = "Kernel code", };
84 static struct resource data_resource = { .name = "Kernel data", };
85 static struct resource bss_resource = { .name = "Kernel bss", };
86 
87 unsigned long __kaslr_offset __ro_after_init;
88 EXPORT_SYMBOL(__kaslr_offset);
89 
90 static void *detect_magic __initdata = detect_memory_region;
91 
92 #ifdef CONFIG_MIPS_AUTO_PFN_OFFSET
93 unsigned long ARCH_PFN_OFFSET;
94 EXPORT_SYMBOL(ARCH_PFN_OFFSET);
95 #endif
96 
97 void __init detect_memory_region(phys_addr_t start, phys_addr_t sz_min, phys_addr_t sz_max)
98 {
99 	void *dm = &detect_magic;
100 	phys_addr_t size;
101 
102 	for (size = sz_min; size < sz_max; size <<= 1) {
103 		if (!memcmp(dm, dm + size, sizeof(detect_magic)))
104 			break;
105 	}
106 
107 	pr_debug("Memory: %lluMB of RAM detected at 0x%llx (min: %lluMB, max: %lluMB)\n",
108 		((unsigned long long) size) / SZ_1M,
109 		(unsigned long long) start,
110 		((unsigned long long) sz_min) / SZ_1M,
111 		((unsigned long long) sz_max) / SZ_1M);
112 
113 	memblock_add(start, size);
114 }
115 
116 /*
117  * Manage initrd
118  */
119 #ifdef CONFIG_BLK_DEV_INITRD
120 
121 static int __init rd_start_early(char *p)
122 {
123 	unsigned long start = memparse(p, &p);
124 
125 #ifdef CONFIG_64BIT
126 	/* Guess if the sign extension was forgotten by bootloader */
127 	if (start < XKPHYS)
128 		start = (int)start;
129 #endif
130 	initrd_start = start;
131 	initrd_end += start;
132 	return 0;
133 }
134 early_param("rd_start", rd_start_early);
135 
136 static int __init rd_size_early(char *p)
137 {
138 	initrd_end += memparse(p, &p);
139 	return 0;
140 }
141 early_param("rd_size", rd_size_early);
142 
143 /* it returns the next free pfn after initrd */
144 static unsigned long __init init_initrd(void)
145 {
146 	unsigned long end;
147 
148 	/*
149 	 * Board specific code or command line parser should have
150 	 * already set up initrd_start and initrd_end. In these cases
151 	 * perfom sanity checks and use them if all looks good.
152 	 */
153 	if (!initrd_start || initrd_end <= initrd_start)
154 		goto disable;
155 
156 	if (initrd_start & ~PAGE_MASK) {
157 		pr_err("initrd start must be page aligned\n");
158 		goto disable;
159 	}
160 	if (initrd_start < PAGE_OFFSET) {
161 		pr_err("initrd start < PAGE_OFFSET\n");
162 		goto disable;
163 	}
164 
165 	/*
166 	 * Sanitize initrd addresses. For example firmware
167 	 * can't guess if they need to pass them through
168 	 * 64-bits values if the kernel has been built in pure
169 	 * 32-bit. We need also to switch from KSEG0 to XKPHYS
170 	 * addresses now, so the code can now safely use __pa().
171 	 */
172 	end = __pa(initrd_end);
173 	initrd_end = (unsigned long)__va(end);
174 	initrd_start = (unsigned long)__va(__pa(initrd_start));
175 
176 	ROOT_DEV = Root_RAM0;
177 	return PFN_UP(end);
178 disable:
179 	initrd_start = 0;
180 	initrd_end = 0;
181 	return 0;
182 }
183 
184 /* In some conditions (e.g. big endian bootloader with a little endian
185    kernel), the initrd might appear byte swapped.  Try to detect this and
186    byte swap it if needed.  */
187 static void __init maybe_bswap_initrd(void)
188 {
189 #if defined(CONFIG_CPU_CAVIUM_OCTEON)
190 	u64 buf;
191 
192 	/* Check for CPIO signature */
193 	if (!memcmp((void *)initrd_start, "070701", 6))
194 		return;
195 
196 	/* Check for compressed initrd */
197 	if (decompress_method((unsigned char *)initrd_start, 8, NULL))
198 		return;
199 
200 	/* Try again with a byte swapped header */
201 	buf = swab64p((u64 *)initrd_start);
202 	if (!memcmp(&buf, "070701", 6) ||
203 	    decompress_method((unsigned char *)(&buf), 8, NULL)) {
204 		unsigned long i;
205 
206 		pr_info("Byteswapped initrd detected\n");
207 		for (i = initrd_start; i < ALIGN(initrd_end, 8); i += 8)
208 			swab64s((u64 *)i);
209 	}
210 #endif
211 }
212 
213 static void __init finalize_initrd(void)
214 {
215 	unsigned long size = initrd_end - initrd_start;
216 
217 	if (size == 0) {
218 		printk(KERN_INFO "Initrd not found or empty");
219 		goto disable;
220 	}
221 	if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
222 		printk(KERN_ERR "Initrd extends beyond end of memory");
223 		goto disable;
224 	}
225 
226 	maybe_bswap_initrd();
227 
228 	memblock_reserve(__pa(initrd_start), size);
229 	initrd_below_start_ok = 1;
230 
231 	pr_info("Initial ramdisk at: 0x%lx (%lu bytes)\n",
232 		initrd_start, size);
233 	return;
234 disable:
235 	printk(KERN_CONT " - disabling initrd\n");
236 	initrd_start = 0;
237 	initrd_end = 0;
238 }
239 
240 #else  /* !CONFIG_BLK_DEV_INITRD */
241 
242 static unsigned long __init init_initrd(void)
243 {
244 	return 0;
245 }
246 
247 #define finalize_initrd()	do {} while (0)
248 
249 #endif
250 
251 /*
252  * Initialize the bootmem allocator. It also setup initrd related data
253  * if needed.
254  */
255 #if defined(CONFIG_SGI_IP27) || (defined(CONFIG_CPU_LOONGSON64) && defined(CONFIG_NUMA))
256 
257 static void __init bootmem_init(void)
258 {
259 	init_initrd();
260 	finalize_initrd();
261 }
262 
263 #else  /* !CONFIG_SGI_IP27 */
264 
265 static void __init bootmem_init(void)
266 {
267 	phys_addr_t ramstart, ramend;
268 	unsigned long start, end;
269 	int i;
270 
271 	ramstart = memblock_start_of_DRAM();
272 	ramend = memblock_end_of_DRAM();
273 
274 	/*
275 	 * Sanity check any INITRD first. We don't take it into account
276 	 * for bootmem setup initially, rely on the end-of-kernel-code
277 	 * as our memory range starting point. Once bootmem is inited we
278 	 * will reserve the area used for the initrd.
279 	 */
280 	init_initrd();
281 
282 	/* Reserve memory occupied by kernel. */
283 	memblock_reserve(__pa_symbol(&_text),
284 			__pa_symbol(&_end) - __pa_symbol(&_text));
285 
286 	/* max_low_pfn is not a number of pages but the end pfn of low mem */
287 
288 #ifdef CONFIG_MIPS_AUTO_PFN_OFFSET
289 	ARCH_PFN_OFFSET = PFN_UP(ramstart);
290 #else
291 	/*
292 	 * Reserve any memory between the start of RAM and PHYS_OFFSET
293 	 */
294 	if (ramstart > PHYS_OFFSET)
295 		memblock_reserve(PHYS_OFFSET, ramstart - PHYS_OFFSET);
296 
297 	if (PFN_UP(ramstart) > ARCH_PFN_OFFSET) {
298 		pr_info("Wasting %lu bytes for tracking %lu unused pages\n",
299 			(unsigned long)((PFN_UP(ramstart) - ARCH_PFN_OFFSET) * sizeof(struct page)),
300 			(unsigned long)(PFN_UP(ramstart) - ARCH_PFN_OFFSET));
301 	}
302 #endif
303 
304 	min_low_pfn = ARCH_PFN_OFFSET;
305 	max_pfn = PFN_DOWN(ramend);
306 	for_each_mem_pfn_range(i, MAX_NUMNODES, &start, &end, NULL) {
307 		/*
308 		 * Skip highmem here so we get an accurate max_low_pfn if low
309 		 * memory stops short of high memory.
310 		 * If the region overlaps HIGHMEM_START, end is clipped so
311 		 * max_pfn excludes the highmem portion.
312 		 */
313 		if (start >= PFN_DOWN(HIGHMEM_START))
314 			continue;
315 		if (end > PFN_DOWN(HIGHMEM_START))
316 			end = PFN_DOWN(HIGHMEM_START);
317 		if (end > max_low_pfn)
318 			max_low_pfn = end;
319 	}
320 
321 	if (min_low_pfn >= max_low_pfn)
322 		panic("Incorrect memory mapping !!!");
323 
324 	if (max_pfn > PFN_DOWN(HIGHMEM_START)) {
325 #ifdef CONFIG_HIGHMEM
326 		highstart_pfn = PFN_DOWN(HIGHMEM_START);
327 		highend_pfn = max_pfn;
328 #else
329 		max_low_pfn = PFN_DOWN(HIGHMEM_START);
330 		max_pfn = max_low_pfn;
331 #endif
332 	}
333 
334 	/*
335 	 * Reserve initrd memory if needed.
336 	 */
337 	finalize_initrd();
338 }
339 
340 #endif	/* CONFIG_SGI_IP27 */
341 
342 static int usermem __initdata;
343 
344 static int __init early_parse_mem(char *p)
345 {
346 	phys_addr_t start, size;
347 
348 	if (!p) {
349 		pr_err("mem parameter is empty, do nothing\n");
350 		return -EINVAL;
351 	}
352 
353 	/*
354 	 * If a user specifies memory size, we
355 	 * blow away any automatically generated
356 	 * size.
357 	 */
358 	if (usermem == 0) {
359 		usermem = 1;
360 		memblock_remove(memblock_start_of_DRAM(),
361 			memblock_end_of_DRAM() - memblock_start_of_DRAM());
362 	}
363 	start = 0;
364 	size = memparse(p, &p);
365 	if (*p == '@')
366 		start = memparse(p + 1, &p);
367 
368 	if (IS_ENABLED(CONFIG_NUMA))
369 		memblock_add_node(start, size, pa_to_nid(start), MEMBLOCK_NONE);
370 	else
371 		memblock_add(start, size);
372 
373 	return 0;
374 }
375 early_param("mem", early_parse_mem);
376 
377 static int __init early_parse_memmap(char *p)
378 {
379 	char *oldp;
380 	u64 start_at, mem_size;
381 
382 	if (!p)
383 		return -EINVAL;
384 
385 	if (!strncmp(p, "exactmap", 8)) {
386 		pr_err("\"memmap=exactmap\" invalid on MIPS\n");
387 		return 0;
388 	}
389 
390 	oldp = p;
391 	mem_size = memparse(p, &p);
392 	if (p == oldp)
393 		return -EINVAL;
394 
395 	if (*p == '@') {
396 		start_at = memparse(p+1, &p);
397 		memblock_add(start_at, mem_size);
398 	} else if (*p == '#') {
399 		pr_err("\"memmap=nn#ss\" (force ACPI data) invalid on MIPS\n");
400 		return -EINVAL;
401 	} else if (*p == '$') {
402 		start_at = memparse(p+1, &p);
403 		memblock_add(start_at, mem_size);
404 		memblock_reserve(start_at, mem_size);
405 	} else {
406 		pr_err("\"memmap\" invalid format!\n");
407 		return -EINVAL;
408 	}
409 
410 	if (*p == '\0') {
411 		usermem = 1;
412 		return 0;
413 	} else
414 		return -EINVAL;
415 }
416 early_param("memmap", early_parse_memmap);
417 
418 static void __init mips_reserve_vmcore(void)
419 {
420 #ifdef CONFIG_PROC_VMCORE
421 	phys_addr_t start, end;
422 	u64 i;
423 
424 	if (!elfcorehdr_size) {
425 		for_each_mem_range(i, &start, &end) {
426 			if (elfcorehdr_addr >= start && elfcorehdr_addr < end) {
427 				/*
428 				 * Reserve from the elf core header to the end of
429 				 * the memory segment, that should all be kdump
430 				 * reserved memory.
431 				 */
432 				elfcorehdr_size = end - elfcorehdr_addr;
433 				break;
434 			}
435 		}
436 	}
437 
438 	pr_info("Reserving %ldKB of memory at %ldKB for kdump\n",
439 		(unsigned long)elfcorehdr_size >> 10, (unsigned long)elfcorehdr_addr >> 10);
440 
441 	memblock_reserve(elfcorehdr_addr, elfcorehdr_size);
442 #endif
443 }
444 
445 #ifdef CONFIG_KEXEC
446 
447 /* 64M alignment for crash kernel regions */
448 #define CRASH_ALIGN	SZ_64M
449 #define CRASH_ADDR_MAX	SZ_512M
450 
451 static void __init mips_parse_crashkernel(void)
452 {
453 	unsigned long long total_mem;
454 	unsigned long long crash_size, crash_base;
455 	int ret;
456 
457 	total_mem = memblock_phys_mem_size();
458 	ret = parse_crashkernel(boot_command_line, total_mem,
459 				&crash_size, &crash_base);
460 	if (ret != 0 || crash_size <= 0)
461 		return;
462 
463 	if (crash_base <= 0) {
464 		crash_base = memblock_phys_alloc_range(crash_size, CRASH_ALIGN,
465 						       CRASH_ALIGN,
466 						       CRASH_ADDR_MAX);
467 		if (!crash_base) {
468 			pr_warn("crashkernel reservation failed - No suitable area found.\n");
469 			return;
470 		}
471 	} else {
472 		unsigned long long start;
473 
474 		start = memblock_phys_alloc_range(crash_size, 1,
475 						  crash_base,
476 						  crash_base + crash_size);
477 		if (start != crash_base) {
478 			pr_warn("Invalid memory region reserved for crash kernel\n");
479 			return;
480 		}
481 	}
482 
483 	crashk_res.start = crash_base;
484 	crashk_res.end	 = crash_base + crash_size - 1;
485 }
486 
487 static void __init request_crashkernel(struct resource *res)
488 {
489 	int ret;
490 
491 	if (crashk_res.start == crashk_res.end)
492 		return;
493 
494 	ret = request_resource(res, &crashk_res);
495 	if (!ret)
496 		pr_info("Reserving %ldMB of memory at %ldMB for crashkernel\n",
497 			(unsigned long)(resource_size(&crashk_res) >> 20),
498 			(unsigned long)(crashk_res.start  >> 20));
499 }
500 #else /* !defined(CONFIG_KEXEC)		*/
501 static void __init mips_parse_crashkernel(void)
502 {
503 }
504 
505 static void __init request_crashkernel(struct resource *res)
506 {
507 }
508 #endif /* !defined(CONFIG_KEXEC)  */
509 
510 static void __init check_kernel_sections_mem(void)
511 {
512 	phys_addr_t start = __pa_symbol(&_text);
513 	phys_addr_t size = __pa_symbol(&_end) - start;
514 
515 	if (!memblock_is_region_memory(start, size)) {
516 		pr_info("Kernel sections are not in the memory maps\n");
517 		memblock_add(start, size);
518 	}
519 }
520 
521 static void __init bootcmdline_append(const char *s, size_t max)
522 {
523 	if (!s[0] || !max)
524 		return;
525 
526 	if (boot_command_line[0])
527 		strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
528 
529 	strlcat(boot_command_line, s, max);
530 }
531 
532 #ifdef CONFIG_OF_EARLY_FLATTREE
533 
534 static int __init bootcmdline_scan_chosen(unsigned long node, const char *uname,
535 					  int depth, void *data)
536 {
537 	bool *dt_bootargs = data;
538 	const char *p;
539 	int l;
540 
541 	if (depth != 1 || !data ||
542 	    (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
543 		return 0;
544 
545 	p = of_get_flat_dt_prop(node, "bootargs", &l);
546 	if (p != NULL && l > 0) {
547 		bootcmdline_append(p, min(l, COMMAND_LINE_SIZE));
548 		*dt_bootargs = true;
549 	}
550 
551 	return 1;
552 }
553 
554 #endif /* CONFIG_OF_EARLY_FLATTREE */
555 
556 static void __init bootcmdline_init(void)
557 {
558 	bool dt_bootargs = false;
559 
560 	/*
561 	 * If CMDLINE_OVERRIDE is enabled then initializing the command line is
562 	 * trivial - we simply use the built-in command line unconditionally &
563 	 * unmodified.
564 	 */
565 	if (IS_ENABLED(CONFIG_CMDLINE_OVERRIDE)) {
566 		strscpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
567 		return;
568 	}
569 
570 	/*
571 	 * If the user specified a built-in command line &
572 	 * MIPS_CMDLINE_BUILTIN_EXTEND, then the built-in command line is
573 	 * prepended to arguments from the bootloader or DT so we'll copy them
574 	 * to the start of boot_command_line here. Otherwise, empty
575 	 * boot_command_line to undo anything early_init_dt_scan_chosen() did.
576 	 */
577 	if (IS_ENABLED(CONFIG_MIPS_CMDLINE_BUILTIN_EXTEND))
578 		strscpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
579 	else
580 		boot_command_line[0] = 0;
581 
582 #ifdef CONFIG_OF_EARLY_FLATTREE
583 	/*
584 	 * If we're configured to take boot arguments from DT, look for those
585 	 * now.
586 	 */
587 	if (IS_ENABLED(CONFIG_MIPS_CMDLINE_FROM_DTB) ||
588 	    IS_ENABLED(CONFIG_MIPS_CMDLINE_DTB_EXTEND))
589 		of_scan_flat_dt(bootcmdline_scan_chosen, &dt_bootargs);
590 #endif
591 
592 	/*
593 	 * If we didn't get any arguments from DT (regardless of whether that's
594 	 * because we weren't configured to look for them, or because we looked
595 	 * & found none) then we'll take arguments from the bootloader.
596 	 * plat_mem_setup() should have filled arcs_cmdline with arguments from
597 	 * the bootloader.
598 	 */
599 	if (IS_ENABLED(CONFIG_MIPS_CMDLINE_DTB_EXTEND) || !dt_bootargs)
600 		bootcmdline_append(arcs_cmdline, COMMAND_LINE_SIZE);
601 
602 	/*
603 	 * If the user specified a built-in command line & we didn't already
604 	 * prepend it, we append it to boot_command_line here.
605 	 */
606 	if (IS_ENABLED(CONFIG_CMDLINE_BOOL) &&
607 	    !IS_ENABLED(CONFIG_MIPS_CMDLINE_BUILTIN_EXTEND))
608 		bootcmdline_append(builtin_cmdline, COMMAND_LINE_SIZE);
609 }
610 
611 /*
612  * arch_mem_init - initialize memory management subsystem
613  *
614  *  o plat_mem_setup() detects the memory configuration and will record detected
615  *    memory areas using memblock_add.
616  *
617  * At this stage the memory configuration of the system is known to the
618  * kernel but generic memory management system is still entirely uninitialized.
619  *
620  *  o bootmem_init()
621  *  o sparse_init()
622  *  o paging_init()
623  *  o dma_contiguous_reserve()
624  *
625  * At this stage the bootmem allocator is ready to use.
626  *
627  * NOTE: historically plat_mem_setup did the entire platform initialization.
628  *	 This was rather impractical because it meant plat_mem_setup had to
629  * get away without any kind of memory allocator.  To keep old code from
630  * breaking plat_setup was just renamed to plat_mem_setup and a second platform
631  * initialization hook for anything else was introduced.
632  */
633 static void __init arch_mem_init(char **cmdline_p)
634 {
635 	/* call board setup routine */
636 	plat_mem_setup();
637 	memblock_set_bottom_up(true);
638 
639 	bootcmdline_init();
640 	strscpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
641 	*cmdline_p = command_line;
642 
643 	parse_early_param();
644 
645 	if (usermem)
646 		pr_info("User-defined physical RAM map overwrite\n");
647 
648 	check_kernel_sections_mem();
649 
650 	early_init_fdt_reserve_self();
651 	early_init_fdt_scan_reserved_mem();
652 
653 #ifndef CONFIG_NUMA
654 	memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
655 #endif
656 	bootmem_init();
657 
658 	/*
659 	 * Prevent memblock from allocating high memory.
660 	 * This cannot be done before max_low_pfn is detected, so up
661 	 * to this point is possible to only reserve physical memory
662 	 * with memblock_reserve; memblock_alloc* can be used
663 	 * only after this point
664 	 */
665 	memblock_set_current_limit(PFN_PHYS(max_low_pfn));
666 
667 	mips_reserve_vmcore();
668 
669 	mips_parse_crashkernel();
670 	device_tree_init();
671 
672 	/*
673 	 * In order to reduce the possibility of kernel panic when failed to
674 	 * get IO TLB memory under CONFIG_SWIOTLB, it is better to allocate
675 	 * low memory as small as possible before plat_swiotlb_setup(), so
676 	 * make sparse_init() using top-down allocation.
677 	 */
678 	memblock_set_bottom_up(false);
679 	sparse_init();
680 	memblock_set_bottom_up(true);
681 
682 	plat_swiotlb_setup();
683 
684 	dma_contiguous_reserve(PFN_PHYS(max_low_pfn));
685 
686 	/* Reserve for hibernation. */
687 	memblock_reserve(__pa_symbol(&__nosave_begin),
688 		__pa_symbol(&__nosave_end) - __pa_symbol(&__nosave_begin));
689 
690 	early_memtest(PFN_PHYS(ARCH_PFN_OFFSET), PFN_PHYS(max_low_pfn));
691 }
692 
693 static void __init resource_init(void)
694 {
695 	phys_addr_t start, end;
696 	u64 i;
697 
698 	if (UNCAC_BASE != IO_BASE)
699 		return;
700 
701 	code_resource.start = __pa_symbol(&_text);
702 	code_resource.end = __pa_symbol(&_etext) - 1;
703 	data_resource.start = __pa_symbol(&_etext);
704 	data_resource.end = __pa_symbol(&_edata) - 1;
705 	bss_resource.start = __pa_symbol(&__bss_start);
706 	bss_resource.end = __pa_symbol(&__bss_stop) - 1;
707 
708 	for_each_mem_range(i, &start, &end) {
709 		struct resource *res;
710 
711 		res = memblock_alloc(sizeof(struct resource), SMP_CACHE_BYTES);
712 		if (!res)
713 			panic("%s: Failed to allocate %zu bytes\n", __func__,
714 			      sizeof(struct resource));
715 
716 		res->start = start;
717 		/*
718 		 * In memblock, end points to the first byte after the
719 		 * range while in resourses, end points to the last byte in
720 		 * the range.
721 		 */
722 		res->end = end - 1;
723 		res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
724 		res->name = "System RAM";
725 
726 		request_resource(&iomem_resource, res);
727 
728 		/*
729 		 *  We don't know which RAM region contains kernel data,
730 		 *  so we try it repeatedly and let the resource manager
731 		 *  test it.
732 		 */
733 		request_resource(res, &code_resource);
734 		request_resource(res, &data_resource);
735 		request_resource(res, &bss_resource);
736 		request_crashkernel(res);
737 	}
738 }
739 
740 #ifdef CONFIG_SMP
741 static void __init prefill_possible_map(void)
742 {
743 	int i, possible = num_possible_cpus();
744 
745 	if (possible > nr_cpu_ids)
746 		possible = nr_cpu_ids;
747 
748 	for (i = 0; i < possible; i++)
749 		set_cpu_possible(i, true);
750 	for (; i < NR_CPUS; i++)
751 		set_cpu_possible(i, false);
752 
753 	nr_cpu_ids = possible;
754 }
755 #else
756 static inline void prefill_possible_map(void) {}
757 #endif
758 
759 void __init setup_arch(char **cmdline_p)
760 {
761 	cpu_probe();
762 	mips_cm_probe();
763 	prom_init();
764 
765 	setup_early_fdc_console();
766 #ifdef CONFIG_EARLY_PRINTK
767 	setup_early_printk();
768 #endif
769 	cpu_report();
770 	check_bugs_early();
771 
772 #if defined(CONFIG_VT)
773 #if defined(CONFIG_VGA_CONSOLE)
774 	conswitchp = &vga_con;
775 #endif
776 #endif
777 
778 	arch_mem_init(cmdline_p);
779 	dmi_setup();
780 
781 	resource_init();
782 	plat_smp_setup();
783 	prefill_possible_map();
784 
785 	cpu_cache_init();
786 	paging_init();
787 
788 	memblock_dump_all();
789 }
790 
791 unsigned long kernelsp[NR_CPUS];
792 unsigned long fw_arg0, fw_arg1, fw_arg2, fw_arg3;
793 
794 #ifdef CONFIG_DEBUG_FS
795 struct dentry *mips_debugfs_dir;
796 static int __init debugfs_mips(void)
797 {
798 	mips_debugfs_dir = debugfs_create_dir("mips", NULL);
799 	return 0;
800 }
801 arch_initcall(debugfs_mips);
802 #endif
803 
804 #ifdef CONFIG_DMA_NONCOHERENT
805 static int __init setcoherentio(char *str)
806 {
807 	dma_default_coherent = true;
808 	pr_info("Hardware DMA cache coherency (command line)\n");
809 	return 0;
810 }
811 early_param("coherentio", setcoherentio);
812 
813 static int __init setnocoherentio(char *str)
814 {
815 	dma_default_coherent = false;
816 	pr_info("Software DMA cache coherency (command line)\n");
817 	return 0;
818 }
819 early_param("nocoherentio", setnocoherentio);
820 #endif
821