xref: /openbmc/linux/arch/mips/kernel/setup.c (revision b296a6d5)
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/of_reserved_mem.h>
31 #include <linux/dmi.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/dma-coherence.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 const 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 static void *detect_magic __initdata = detect_memory_region;
88 
89 #ifdef CONFIG_MIPS_AUTO_PFN_OFFSET
90 unsigned long ARCH_PFN_OFFSET;
91 EXPORT_SYMBOL(ARCH_PFN_OFFSET);
92 #endif
93 
94 void __init add_memory_region(phys_addr_t start, phys_addr_t size, long type)
95 {
96 	/*
97 	 * Note: This function only exists for historical reason,
98 	 * new code should use memblock_add or memblock_add_node instead.
99 	 */
100 
101 	/*
102 	 * If the region reaches the top of the physical address space, adjust
103 	 * the size slightly so that (start + size) doesn't overflow
104 	 */
105 	if (start + size - 1 == PHYS_ADDR_MAX)
106 		--size;
107 
108 	/* Sanity check */
109 	if (start + size < start) {
110 		pr_warn("Trying to add an invalid memory region, skipped\n");
111 		return;
112 	}
113 
114 	if (start < PHYS_OFFSET)
115 		return;
116 
117 	memblock_add(start, size);
118 	/* Reserve any memory except the ordinary RAM ranges. */
119 	switch (type) {
120 	case BOOT_MEM_RAM:
121 		break;
122 
123 	case BOOT_MEM_NOMAP: /* Discard the range from the system. */
124 		memblock_remove(start, size);
125 		break;
126 
127 	default: /* Reserve the rest of the memory types at boot time */
128 		memblock_reserve(start, size);
129 		break;
130 	}
131 }
132 
133 void __init detect_memory_region(phys_addr_t start, phys_addr_t sz_min, phys_addr_t sz_max)
134 {
135 	void *dm = &detect_magic;
136 	phys_addr_t size;
137 
138 	for (size = sz_min; size < sz_max; size <<= 1) {
139 		if (!memcmp(dm, dm + size, sizeof(detect_magic)))
140 			break;
141 	}
142 
143 	pr_debug("Memory: %lluMB of RAM detected at 0x%llx (min: %lluMB, max: %lluMB)\n",
144 		((unsigned long long) size) / SZ_1M,
145 		(unsigned long long) start,
146 		((unsigned long long) sz_min) / SZ_1M,
147 		((unsigned long long) sz_max) / SZ_1M);
148 
149 	add_memory_region(start, size, BOOT_MEM_RAM);
150 }
151 
152 /*
153  * Manage initrd
154  */
155 #ifdef CONFIG_BLK_DEV_INITRD
156 
157 static int __init rd_start_early(char *p)
158 {
159 	unsigned long start = memparse(p, &p);
160 
161 #ifdef CONFIG_64BIT
162 	/* Guess if the sign extension was forgotten by bootloader */
163 	if (start < XKPHYS)
164 		start = (int)start;
165 #endif
166 	initrd_start = start;
167 	initrd_end += start;
168 	return 0;
169 }
170 early_param("rd_start", rd_start_early);
171 
172 static int __init rd_size_early(char *p)
173 {
174 	initrd_end += memparse(p, &p);
175 	return 0;
176 }
177 early_param("rd_size", rd_size_early);
178 
179 /* it returns the next free pfn after initrd */
180 static unsigned long __init init_initrd(void)
181 {
182 	unsigned long end;
183 
184 	/*
185 	 * Board specific code or command line parser should have
186 	 * already set up initrd_start and initrd_end. In these cases
187 	 * perfom sanity checks and use them if all looks good.
188 	 */
189 	if (!initrd_start || initrd_end <= initrd_start)
190 		goto disable;
191 
192 	if (initrd_start & ~PAGE_MASK) {
193 		pr_err("initrd start must be page aligned\n");
194 		goto disable;
195 	}
196 	if (initrd_start < PAGE_OFFSET) {
197 		pr_err("initrd start < PAGE_OFFSET\n");
198 		goto disable;
199 	}
200 
201 	/*
202 	 * Sanitize initrd addresses. For example firmware
203 	 * can't guess if they need to pass them through
204 	 * 64-bits values if the kernel has been built in pure
205 	 * 32-bit. We need also to switch from KSEG0 to XKPHYS
206 	 * addresses now, so the code can now safely use __pa().
207 	 */
208 	end = __pa(initrd_end);
209 	initrd_end = (unsigned long)__va(end);
210 	initrd_start = (unsigned long)__va(__pa(initrd_start));
211 
212 	ROOT_DEV = Root_RAM0;
213 	return PFN_UP(end);
214 disable:
215 	initrd_start = 0;
216 	initrd_end = 0;
217 	return 0;
218 }
219 
220 /* In some conditions (e.g. big endian bootloader with a little endian
221    kernel), the initrd might appear byte swapped.  Try to detect this and
222    byte swap it if needed.  */
223 static void __init maybe_bswap_initrd(void)
224 {
225 #if defined(CONFIG_CPU_CAVIUM_OCTEON)
226 	u64 buf;
227 
228 	/* Check for CPIO signature */
229 	if (!memcmp((void *)initrd_start, "070701", 6))
230 		return;
231 
232 	/* Check for compressed initrd */
233 	if (decompress_method((unsigned char *)initrd_start, 8, NULL))
234 		return;
235 
236 	/* Try again with a byte swapped header */
237 	buf = swab64p((u64 *)initrd_start);
238 	if (!memcmp(&buf, "070701", 6) ||
239 	    decompress_method((unsigned char *)(&buf), 8, NULL)) {
240 		unsigned long i;
241 
242 		pr_info("Byteswapped initrd detected\n");
243 		for (i = initrd_start; i < ALIGN(initrd_end, 8); i += 8)
244 			swab64s((u64 *)i);
245 	}
246 #endif
247 }
248 
249 static void __init finalize_initrd(void)
250 {
251 	unsigned long size = initrd_end - initrd_start;
252 
253 	if (size == 0) {
254 		printk(KERN_INFO "Initrd not found or empty");
255 		goto disable;
256 	}
257 	if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
258 		printk(KERN_ERR "Initrd extends beyond end of memory");
259 		goto disable;
260 	}
261 
262 	maybe_bswap_initrd();
263 
264 	memblock_reserve(__pa(initrd_start), size);
265 	initrd_below_start_ok = 1;
266 
267 	pr_info("Initial ramdisk at: 0x%lx (%lu bytes)\n",
268 		initrd_start, size);
269 	return;
270 disable:
271 	printk(KERN_CONT " - disabling initrd\n");
272 	initrd_start = 0;
273 	initrd_end = 0;
274 }
275 
276 #else  /* !CONFIG_BLK_DEV_INITRD */
277 
278 static unsigned long __init init_initrd(void)
279 {
280 	return 0;
281 }
282 
283 #define finalize_initrd()	do {} while (0)
284 
285 #endif
286 
287 /*
288  * Initialize the bootmem allocator. It also setup initrd related data
289  * if needed.
290  */
291 #if defined(CONFIG_SGI_IP27) || (defined(CONFIG_CPU_LOONGSON64) && defined(CONFIG_NUMA))
292 
293 static void __init bootmem_init(void)
294 {
295 	init_initrd();
296 	finalize_initrd();
297 }
298 
299 #else  /* !CONFIG_SGI_IP27 */
300 
301 static void __init bootmem_init(void)
302 {
303 	phys_addr_t ramstart, ramend;
304 	phys_addr_t start, end;
305 	u64 i;
306 
307 	ramstart = memblock_start_of_DRAM();
308 	ramend = memblock_end_of_DRAM();
309 
310 	/*
311 	 * Sanity check any INITRD first. We don't take it into account
312 	 * for bootmem setup initially, rely on the end-of-kernel-code
313 	 * as our memory range starting point. Once bootmem is inited we
314 	 * will reserve the area used for the initrd.
315 	 */
316 	init_initrd();
317 
318 	/* Reserve memory occupied by kernel. */
319 	memblock_reserve(__pa_symbol(&_text),
320 			__pa_symbol(&_end) - __pa_symbol(&_text));
321 
322 	/* max_low_pfn is not a number of pages but the end pfn of low mem */
323 
324 #ifdef CONFIG_MIPS_AUTO_PFN_OFFSET
325 	ARCH_PFN_OFFSET = PFN_UP(ramstart);
326 #else
327 	/*
328 	 * Reserve any memory between the start of RAM and PHYS_OFFSET
329 	 */
330 	if (ramstart > PHYS_OFFSET)
331 		memblock_reserve(PHYS_OFFSET, ramstart - PHYS_OFFSET);
332 
333 	if (PFN_UP(ramstart) > ARCH_PFN_OFFSET) {
334 		pr_info("Wasting %lu bytes for tracking %lu unused pages\n",
335 			(unsigned long)((PFN_UP(ramstart) - ARCH_PFN_OFFSET) * sizeof(struct page)),
336 			(unsigned long)(PFN_UP(ramstart) - ARCH_PFN_OFFSET));
337 	}
338 #endif
339 
340 	min_low_pfn = ARCH_PFN_OFFSET;
341 	max_pfn = PFN_DOWN(ramend);
342 	for_each_mem_range(i, &start, &end) {
343 		/*
344 		 * Skip highmem here so we get an accurate max_low_pfn if low
345 		 * memory stops short of high memory.
346 		 * If the region overlaps HIGHMEM_START, end is clipped so
347 		 * max_pfn excludes the highmem portion.
348 		 */
349 		if (start >= PFN_DOWN(HIGHMEM_START))
350 			continue;
351 		if (end > PFN_DOWN(HIGHMEM_START))
352 			end = PFN_DOWN(HIGHMEM_START);
353 		if (end > max_low_pfn)
354 			max_low_pfn = end;
355 	}
356 
357 	if (min_low_pfn >= max_low_pfn)
358 		panic("Incorrect memory mapping !!!");
359 
360 	if (max_pfn > PFN_DOWN(HIGHMEM_START)) {
361 #ifdef CONFIG_HIGHMEM
362 		highstart_pfn = PFN_DOWN(HIGHMEM_START);
363 		highend_pfn = max_pfn;
364 #else
365 		max_low_pfn = PFN_DOWN(HIGHMEM_START);
366 		max_pfn = max_low_pfn;
367 #endif
368 	}
369 
370 	/*
371 	 * Reserve initrd memory if needed.
372 	 */
373 	finalize_initrd();
374 }
375 
376 #endif	/* CONFIG_SGI_IP27 */
377 
378 static int usermem __initdata;
379 
380 static int __init early_parse_mem(char *p)
381 {
382 	phys_addr_t start, size;
383 
384 	/*
385 	 * If a user specifies memory size, we
386 	 * blow away any automatically generated
387 	 * size.
388 	 */
389 	if (usermem == 0) {
390 		usermem = 1;
391 		memblock_remove(memblock_start_of_DRAM(),
392 			memblock_end_of_DRAM() - memblock_start_of_DRAM());
393 	}
394 	start = 0;
395 	size = memparse(p, &p);
396 	if (*p == '@')
397 		start = memparse(p + 1, &p);
398 
399 	add_memory_region(start, size, BOOT_MEM_RAM);
400 
401 	return 0;
402 }
403 early_param("mem", early_parse_mem);
404 
405 static int __init early_parse_memmap(char *p)
406 {
407 	char *oldp;
408 	u64 start_at, mem_size;
409 
410 	if (!p)
411 		return -EINVAL;
412 
413 	if (!strncmp(p, "exactmap", 8)) {
414 		pr_err("\"memmap=exactmap\" invalid on MIPS\n");
415 		return 0;
416 	}
417 
418 	oldp = p;
419 	mem_size = memparse(p, &p);
420 	if (p == oldp)
421 		return -EINVAL;
422 
423 	if (*p == '@') {
424 		start_at = memparse(p+1, &p);
425 		add_memory_region(start_at, mem_size, BOOT_MEM_RAM);
426 	} else if (*p == '#') {
427 		pr_err("\"memmap=nn#ss\" (force ACPI data) invalid on MIPS\n");
428 		return -EINVAL;
429 	} else if (*p == '$') {
430 		start_at = memparse(p+1, &p);
431 		add_memory_region(start_at, mem_size, BOOT_MEM_RESERVED);
432 	} else {
433 		pr_err("\"memmap\" invalid format!\n");
434 		return -EINVAL;
435 	}
436 
437 	if (*p == '\0') {
438 		usermem = 1;
439 		return 0;
440 	} else
441 		return -EINVAL;
442 }
443 early_param("memmap", early_parse_memmap);
444 
445 #ifdef CONFIG_PROC_VMCORE
446 unsigned long setup_elfcorehdr, setup_elfcorehdr_size;
447 static int __init early_parse_elfcorehdr(char *p)
448 {
449 	phys_addr_t start, end;
450 	u64 i;
451 
452 	setup_elfcorehdr = memparse(p, &p);
453 
454 	for_each_mem_range(i, &start, &end) {
455 		if (setup_elfcorehdr >= start && setup_elfcorehdr < end) {
456 			/*
457 			 * Reserve from the elf core header to the end of
458 			 * the memory segment, that should all be kdump
459 			 * reserved memory.
460 			 */
461 			setup_elfcorehdr_size = end - setup_elfcorehdr;
462 			break;
463 		}
464 	}
465 	/*
466 	 * If we don't find it in the memory map, then we shouldn't
467 	 * have to worry about it, as the new kernel won't use it.
468 	 */
469 	return 0;
470 }
471 early_param("elfcorehdr", early_parse_elfcorehdr);
472 #endif
473 
474 #ifdef CONFIG_KEXEC
475 static void __init mips_parse_crashkernel(void)
476 {
477 	unsigned long long total_mem;
478 	unsigned long long crash_size, crash_base;
479 	int ret;
480 
481 	total_mem = memblock_phys_mem_size();
482 	ret = parse_crashkernel(boot_command_line, total_mem,
483 				&crash_size, &crash_base);
484 	if (ret != 0 || crash_size <= 0)
485 		return;
486 
487 	if (!memblock_find_in_range(crash_base, crash_base + crash_size, crash_size, 1)) {
488 		pr_warn("Invalid memory region reserved for crash kernel\n");
489 		return;
490 	}
491 
492 	crashk_res.start = crash_base;
493 	crashk_res.end	 = crash_base + crash_size - 1;
494 }
495 
496 static void __init request_crashkernel(struct resource *res)
497 {
498 	int ret;
499 
500 	if (crashk_res.start == crashk_res.end)
501 		return;
502 
503 	ret = request_resource(res, &crashk_res);
504 	if (!ret)
505 		pr_info("Reserving %ldMB of memory at %ldMB for crashkernel\n",
506 			(unsigned long)(resource_size(&crashk_res) >> 20),
507 			(unsigned long)(crashk_res.start  >> 20));
508 }
509 #else /* !defined(CONFIG_KEXEC)		*/
510 static void __init mips_parse_crashkernel(void)
511 {
512 }
513 
514 static void __init request_crashkernel(struct resource *res)
515 {
516 }
517 #endif /* !defined(CONFIG_KEXEC)  */
518 
519 static void __init check_kernel_sections_mem(void)
520 {
521 	phys_addr_t start = PFN_PHYS(PFN_DOWN(__pa_symbol(&_text)));
522 	phys_addr_t size = PFN_PHYS(PFN_UP(__pa_symbol(&_end))) - start;
523 
524 	if (!memblock_is_region_memory(start, size)) {
525 		pr_info("Kernel sections are not in the memory maps\n");
526 		memblock_add(start, size);
527 	}
528 }
529 
530 static void __init bootcmdline_append(const char *s, size_t max)
531 {
532 	if (!s[0] || !max)
533 		return;
534 
535 	if (boot_command_line[0])
536 		strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
537 
538 	strlcat(boot_command_line, s, max);
539 }
540 
541 #ifdef CONFIG_OF_EARLY_FLATTREE
542 
543 static int __init bootcmdline_scan_chosen(unsigned long node, const char *uname,
544 					  int depth, void *data)
545 {
546 	bool *dt_bootargs = data;
547 	const char *p;
548 	int l;
549 
550 	if (depth != 1 || !data ||
551 	    (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
552 		return 0;
553 
554 	p = of_get_flat_dt_prop(node, "bootargs", &l);
555 	if (p != NULL && l > 0) {
556 		bootcmdline_append(p, min(l, COMMAND_LINE_SIZE));
557 		*dt_bootargs = true;
558 	}
559 
560 	return 1;
561 }
562 
563 #endif /* CONFIG_OF_EARLY_FLATTREE */
564 
565 static void __init bootcmdline_init(void)
566 {
567 	bool dt_bootargs = false;
568 
569 	/*
570 	 * If CMDLINE_OVERRIDE is enabled then initializing the command line is
571 	 * trivial - we simply use the built-in command line unconditionally &
572 	 * unmodified.
573 	 */
574 	if (IS_ENABLED(CONFIG_CMDLINE_OVERRIDE)) {
575 		strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
576 		return;
577 	}
578 
579 	/*
580 	 * If the user specified a built-in command line &
581 	 * MIPS_CMDLINE_BUILTIN_EXTEND, then the built-in command line is
582 	 * prepended to arguments from the bootloader or DT so we'll copy them
583 	 * to the start of boot_command_line here. Otherwise, empty
584 	 * boot_command_line to undo anything early_init_dt_scan_chosen() did.
585 	 */
586 	if (IS_ENABLED(CONFIG_MIPS_CMDLINE_BUILTIN_EXTEND))
587 		strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
588 	else
589 		boot_command_line[0] = 0;
590 
591 #ifdef CONFIG_OF_EARLY_FLATTREE
592 	/*
593 	 * If we're configured to take boot arguments from DT, look for those
594 	 * now.
595 	 */
596 	if (IS_ENABLED(CONFIG_MIPS_CMDLINE_FROM_DTB) ||
597 	    IS_ENABLED(CONFIG_MIPS_CMDLINE_DTB_EXTEND))
598 		of_scan_flat_dt(bootcmdline_scan_chosen, &dt_bootargs);
599 #endif
600 
601 	/*
602 	 * If we didn't get any arguments from DT (regardless of whether that's
603 	 * because we weren't configured to look for them, or because we looked
604 	 * & found none) then we'll take arguments from the bootloader.
605 	 * plat_mem_setup() should have filled arcs_cmdline with arguments from
606 	 * the bootloader.
607 	 */
608 	if (IS_ENABLED(CONFIG_MIPS_CMDLINE_DTB_EXTEND) || !dt_bootargs)
609 		bootcmdline_append(arcs_cmdline, COMMAND_LINE_SIZE);
610 
611 	/*
612 	 * If the user specified a built-in command line & we didn't already
613 	 * prepend it, we append it to boot_command_line here.
614 	 */
615 	if (IS_ENABLED(CONFIG_CMDLINE_BOOL) &&
616 	    !IS_ENABLED(CONFIG_MIPS_CMDLINE_BUILTIN_EXTEND))
617 		bootcmdline_append(builtin_cmdline, COMMAND_LINE_SIZE);
618 }
619 
620 /*
621  * arch_mem_init - initialize memory management subsystem
622  *
623  *  o plat_mem_setup() detects the memory configuration and will record detected
624  *    memory areas using add_memory_region.
625  *
626  * At this stage the memory configuration of the system is known to the
627  * kernel but generic memory management system is still entirely uninitialized.
628  *
629  *  o bootmem_init()
630  *  o sparse_init()
631  *  o paging_init()
632  *  o dma_contiguous_reserve()
633  *
634  * At this stage the bootmem allocator is ready to use.
635  *
636  * NOTE: historically plat_mem_setup did the entire platform initialization.
637  *	 This was rather impractical because it meant plat_mem_setup had to
638  * get away without any kind of memory allocator.  To keep old code from
639  * breaking plat_setup was just renamed to plat_mem_setup and a second platform
640  * initialization hook for anything else was introduced.
641  */
642 static void __init arch_mem_init(char **cmdline_p)
643 {
644 	/* call board setup routine */
645 	plat_mem_setup();
646 	memblock_set_bottom_up(true);
647 
648 	bootcmdline_init();
649 	strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
650 	*cmdline_p = command_line;
651 
652 	parse_early_param();
653 
654 	if (usermem)
655 		pr_info("User-defined physical RAM map overwrite\n");
656 
657 	check_kernel_sections_mem();
658 
659 	early_init_fdt_reserve_self();
660 	early_init_fdt_scan_reserved_mem();
661 
662 #ifndef CONFIG_NUMA
663 	memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
664 #endif
665 	bootmem_init();
666 
667 	/*
668 	 * Prevent memblock from allocating high memory.
669 	 * This cannot be done before max_low_pfn is detected, so up
670 	 * to this point is possible to only reserve physical memory
671 	 * with memblock_reserve; memblock_alloc* can be used
672 	 * only after this point
673 	 */
674 	memblock_set_current_limit(PFN_PHYS(max_low_pfn));
675 
676 #ifdef CONFIG_PROC_VMCORE
677 	if (setup_elfcorehdr && setup_elfcorehdr_size) {
678 		printk(KERN_INFO "kdump reserved memory at %lx-%lx\n",
679 		       setup_elfcorehdr, setup_elfcorehdr_size);
680 		memblock_reserve(setup_elfcorehdr, setup_elfcorehdr_size);
681 	}
682 #endif
683 
684 	mips_parse_crashkernel();
685 #ifdef CONFIG_KEXEC
686 	if (crashk_res.start != crashk_res.end)
687 		memblock_reserve(crashk_res.start, resource_size(&crashk_res));
688 #endif
689 	device_tree_init();
690 
691 	/*
692 	 * In order to reduce the possibility of kernel panic when failed to
693 	 * get IO TLB memory under CONFIG_SWIOTLB, it is better to allocate
694 	 * low memory as small as possible before plat_swiotlb_setup(), so
695 	 * make sparse_init() using top-down allocation.
696 	 */
697 	memblock_set_bottom_up(false);
698 	sparse_init();
699 	memblock_set_bottom_up(true);
700 
701 	plat_swiotlb_setup();
702 
703 	dma_contiguous_reserve(PFN_PHYS(max_low_pfn));
704 
705 	/* Reserve for hibernation. */
706 	memblock_reserve(__pa_symbol(&__nosave_begin),
707 		__pa_symbol(&__nosave_end) - __pa_symbol(&__nosave_begin));
708 
709 	fdt_init_reserved_mem();
710 
711 	memblock_dump_all();
712 
713 	early_memtest(PFN_PHYS(ARCH_PFN_OFFSET), PFN_PHYS(max_low_pfn));
714 }
715 
716 static void __init resource_init(void)
717 {
718 	phys_addr_t start, end;
719 	u64 i;
720 
721 	if (UNCAC_BASE != IO_BASE)
722 		return;
723 
724 	code_resource.start = __pa_symbol(&_text);
725 	code_resource.end = __pa_symbol(&_etext) - 1;
726 	data_resource.start = __pa_symbol(&_etext);
727 	data_resource.end = __pa_symbol(&_edata) - 1;
728 	bss_resource.start = __pa_symbol(&__bss_start);
729 	bss_resource.end = __pa_symbol(&__bss_stop) - 1;
730 
731 	for_each_mem_range(i, &start, &end) {
732 		struct resource *res;
733 
734 		res = memblock_alloc(sizeof(struct resource), SMP_CACHE_BYTES);
735 		if (!res)
736 			panic("%s: Failed to allocate %zu bytes\n", __func__,
737 			      sizeof(struct resource));
738 
739 		res->start = start;
740 		/*
741 		 * In memblock, end points to the first byte after the
742 		 * range while in resourses, end points to the last byte in
743 		 * the range.
744 		 */
745 		res->end = end - 1;
746 		res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
747 		res->name = "System RAM";
748 
749 		request_resource(&iomem_resource, res);
750 
751 		/*
752 		 *  We don't know which RAM region contains kernel data,
753 		 *  so we try it repeatedly and let the resource manager
754 		 *  test it.
755 		 */
756 		request_resource(res, &code_resource);
757 		request_resource(res, &data_resource);
758 		request_resource(res, &bss_resource);
759 		request_crashkernel(res);
760 	}
761 }
762 
763 #ifdef CONFIG_SMP
764 static void __init prefill_possible_map(void)
765 {
766 	int i, possible = num_possible_cpus();
767 
768 	if (possible > nr_cpu_ids)
769 		possible = nr_cpu_ids;
770 
771 	for (i = 0; i < possible; i++)
772 		set_cpu_possible(i, true);
773 	for (; i < NR_CPUS; i++)
774 		set_cpu_possible(i, false);
775 
776 	nr_cpu_ids = possible;
777 }
778 #else
779 static inline void prefill_possible_map(void) {}
780 #endif
781 
782 void __init setup_arch(char **cmdline_p)
783 {
784 	cpu_probe();
785 	mips_cm_probe();
786 	prom_init();
787 
788 	setup_early_fdc_console();
789 #ifdef CONFIG_EARLY_PRINTK
790 	setup_early_printk();
791 #endif
792 	cpu_report();
793 	check_bugs_early();
794 
795 #if defined(CONFIG_VT)
796 #if defined(CONFIG_VGA_CONSOLE)
797 	conswitchp = &vga_con;
798 #endif
799 #endif
800 
801 	arch_mem_init(cmdline_p);
802 	dmi_setup();
803 
804 	resource_init();
805 	plat_smp_setup();
806 	prefill_possible_map();
807 
808 	cpu_cache_init();
809 	paging_init();
810 }
811 
812 unsigned long kernelsp[NR_CPUS];
813 unsigned long fw_arg0, fw_arg1, fw_arg2, fw_arg3;
814 
815 #ifdef CONFIG_USE_OF
816 unsigned long fw_passed_dtb;
817 #endif
818 
819 #ifdef CONFIG_DEBUG_FS
820 struct dentry *mips_debugfs_dir;
821 static int __init debugfs_mips(void)
822 {
823 	mips_debugfs_dir = debugfs_create_dir("mips", NULL);
824 	return 0;
825 }
826 arch_initcall(debugfs_mips);
827 #endif
828 
829 #ifdef CONFIG_DMA_MAYBE_COHERENT
830 /* User defined DMA coherency from command line. */
831 enum coherent_io_user_state coherentio = IO_COHERENCE_DEFAULT;
832 EXPORT_SYMBOL_GPL(coherentio);
833 int hw_coherentio;	/* Actual hardware supported DMA coherency setting. */
834 
835 static int __init setcoherentio(char *str)
836 {
837 	coherentio = IO_COHERENCE_ENABLED;
838 	pr_info("Hardware DMA cache coherency (command line)\n");
839 	return 0;
840 }
841 early_param("coherentio", setcoherentio);
842 
843 static int __init setnocoherentio(char *str)
844 {
845 	coherentio = IO_COHERENCE_DISABLED;
846 	pr_info("Software DMA cache coherency (command line)\n");
847 	return 0;
848 }
849 early_param("nocoherentio", setnocoherentio);
850 #endif
851