xref: /linux/arch/mips/kernel/setup.c (revision 14ac09a65e19528ca05df56f8e36a4a8d4949795)
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 
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 static char __initdata command_line[COMMAND_LINE_SIZE];
67 char __initdata arcs_cmdline[COMMAND_LINE_SIZE];
68 
69 #ifdef CONFIG_CMDLINE_BOOL
70 static const char builtin_cmdline[] __initconst = CONFIG_CMDLINE;
71 #else
72 static const char builtin_cmdline[] __initconst = "";
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 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 unsigned long __kaslr_offset __ro_after_init;
87 EXPORT_SYMBOL(__kaslr_offset);
88 
89 static void *detect_magic __initdata = detect_memory_region;
90 
91 #ifdef CONFIG_MIPS_AUTO_PFN_OFFSET
92 unsigned long ARCH_PFN_OFFSET;
93 EXPORT_SYMBOL(ARCH_PFN_OFFSET);
94 #endif
95 
96 void __init detect_memory_region(phys_addr_t start, phys_addr_t sz_min, phys_addr_t sz_max)
97 {
98 	void *dm = &detect_magic;
99 	phys_addr_t size;
100 
101 	for (size = sz_min; size < sz_max; size <<= 1) {
102 		if (!memcmp(dm, dm + size, sizeof(detect_magic)))
103 			break;
104 	}
105 
106 	pr_debug("Memory: %lluMB of RAM detected at 0x%llx (min: %lluMB, max: %lluMB)\n",
107 		((unsigned long long) size) / SZ_1M,
108 		(unsigned long long) start,
109 		((unsigned long long) sz_min) / SZ_1M,
110 		((unsigned long long) sz_max) / SZ_1M);
111 
112 	memblock_add(start, size);
113 }
114 
115 /*
116  * Manage initrd
117  */
118 #ifdef CONFIG_BLK_DEV_INITRD
119 
120 static int __init rd_start_early(char *p)
121 {
122 	unsigned long start = memparse(p, &p);
123 
124 #ifdef CONFIG_64BIT
125 	/* Guess if the sign extension was forgotten by bootloader */
126 	if (start < XKPHYS)
127 		start = (int)start;
128 #endif
129 	initrd_start = start;
130 	initrd_end += start;
131 	return 0;
132 }
133 early_param("rd_start", rd_start_early);
134 
135 static int __init rd_size_early(char *p)
136 {
137 	initrd_end += memparse(p, &p);
138 	return 0;
139 }
140 early_param("rd_size", rd_size_early);
141 
142 /* it returns the next free pfn after initrd */
143 static unsigned long __init init_initrd(void)
144 {
145 	unsigned long end;
146 
147 	/*
148 	 * Board specific code or command line parser should have
149 	 * already set up initrd_start and initrd_end. In these cases
150 	 * perfom sanity checks and use them if all looks good.
151 	 */
152 	if (!initrd_start || initrd_end <= initrd_start)
153 		goto disable;
154 
155 	if (initrd_start & ~PAGE_MASK) {
156 		pr_err("initrd start must be page aligned\n");
157 		goto disable;
158 	}
159 	if (initrd_start < PAGE_OFFSET) {
160 		pr_err("initrd start < PAGE_OFFSET\n");
161 		goto disable;
162 	}
163 
164 	/*
165 	 * Sanitize initrd addresses. For example firmware
166 	 * can't guess if they need to pass them through
167 	 * 64-bits values if the kernel has been built in pure
168 	 * 32-bit. We need also to switch from KSEG0 to XKPHYS
169 	 * addresses now, so the code can now safely use __pa().
170 	 */
171 	end = __pa(initrd_end);
172 	initrd_end = (unsigned long)__va(end);
173 	initrd_start = (unsigned long)__va(__pa(initrd_start));
174 
175 	ROOT_DEV = Root_RAM0;
176 	return PFN_UP(end);
177 disable:
178 	initrd_start = 0;
179 	initrd_end = 0;
180 	return 0;
181 }
182 
183 /* In some conditions (e.g. big endian bootloader with a little endian
184    kernel), the initrd might appear byte swapped.  Try to detect this and
185    byte swap it if needed.  */
186 static void __init maybe_bswap_initrd(void)
187 {
188 #if defined(CONFIG_CPU_CAVIUM_OCTEON)
189 	u64 buf;
190 
191 	/* Check for CPIO signature */
192 	if (!memcmp((void *)initrd_start, "070701", 6))
193 		return;
194 
195 	/* Check for compressed initrd */
196 	if (decompress_method((unsigned char *)initrd_start, 8, NULL))
197 		return;
198 
199 	/* Try again with a byte swapped header */
200 	buf = swab64p((u64 *)initrd_start);
201 	if (!memcmp(&buf, "070701", 6) ||
202 	    decompress_method((unsigned char *)(&buf), 8, NULL)) {
203 		unsigned long i;
204 
205 		pr_info("Byteswapped initrd detected\n");
206 		for (i = initrd_start; i < ALIGN(initrd_end, 8); i += 8)
207 			swab64s((u64 *)i);
208 	}
209 #endif
210 }
211 
212 static void __init finalize_initrd(void)
213 {
214 	unsigned long size = initrd_end - initrd_start;
215 
216 	if (size == 0) {
217 		printk(KERN_INFO "Initrd not found or empty");
218 		goto disable;
219 	}
220 	if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
221 		printk(KERN_ERR "Initrd extends beyond end of memory");
222 		goto disable;
223 	}
224 
225 	maybe_bswap_initrd();
226 
227 	memblock_reserve(__pa(initrd_start), size);
228 	initrd_below_start_ok = 1;
229 
230 	pr_info("Initial ramdisk at: 0x%lx (%lu bytes)\n",
231 		initrd_start, size);
232 	return;
233 disable:
234 	printk(KERN_CONT " - disabling initrd\n");
235 	initrd_start = 0;
236 	initrd_end = 0;
237 }
238 
239 #else  /* !CONFIG_BLK_DEV_INITRD */
240 
241 static unsigned long __init init_initrd(void)
242 {
243 	return 0;
244 }
245 
246 #define finalize_initrd()	do {} while (0)
247 
248 #endif
249 
250 /*
251  * Initialize the bootmem allocator. It also setup initrd related data
252  * if needed.
253  */
254 #if defined(CONFIG_SGI_IP27) || (defined(CONFIG_CPU_LOONGSON64) && defined(CONFIG_NUMA))
255 
256 static void __init bootmem_init(void)
257 {
258 	init_initrd();
259 	finalize_initrd();
260 }
261 
262 #else  /* !CONFIG_SGI_IP27 */
263 
264 static void __init bootmem_init(void)
265 {
266 	phys_addr_t ramstart, ramend;
267 	unsigned long start, end;
268 	int i;
269 
270 	ramstart = memblock_start_of_DRAM();
271 	ramend = memblock_end_of_DRAM();
272 
273 	/*
274 	 * Sanity check any INITRD first. We don't take it into account
275 	 * for bootmem setup initially, rely on the end-of-kernel-code
276 	 * as our memory range starting point. Once bootmem is inited we
277 	 * will reserve the area used for the initrd.
278 	 */
279 	init_initrd();
280 
281 	/* Reserve memory occupied by kernel. */
282 	memblock_reserve(__pa_symbol(&_text),
283 			__pa_symbol(&_end) - __pa_symbol(&_text));
284 
285 	/* max_low_pfn is not a number of pages but the end pfn of low mem */
286 
287 #ifdef CONFIG_MIPS_AUTO_PFN_OFFSET
288 	ARCH_PFN_OFFSET = PFN_UP(ramstart);
289 #else
290 	/*
291 	 * Reserve any memory between the start of RAM and PHYS_OFFSET
292 	 */
293 	if (ramstart > PHYS_OFFSET)
294 		memblock_reserve(PHYS_OFFSET, ramstart - PHYS_OFFSET);
295 
296 	if (PFN_UP(ramstart) > ARCH_PFN_OFFSET) {
297 		pr_info("Wasting %lu bytes for tracking %lu unused pages\n",
298 			(unsigned long)((PFN_UP(ramstart) - ARCH_PFN_OFFSET) * sizeof(struct page)),
299 			(unsigned long)(PFN_UP(ramstart) - ARCH_PFN_OFFSET));
300 	}
301 #endif
302 
303 	min_low_pfn = ARCH_PFN_OFFSET;
304 	max_pfn = PFN_DOWN(ramend);
305 	for_each_mem_pfn_range(i, MAX_NUMNODES, &start, &end, NULL) {
306 		/*
307 		 * Skip highmem here so we get an accurate max_low_pfn if low
308 		 * memory stops short of high memory.
309 		 * If the region overlaps HIGHMEM_START, end is clipped so
310 		 * max_pfn excludes the highmem portion.
311 		 */
312 		if (start >= PFN_DOWN(HIGHMEM_START))
313 			continue;
314 		if (end > PFN_DOWN(HIGHMEM_START))
315 			end = PFN_DOWN(HIGHMEM_START);
316 		if (end > max_low_pfn)
317 			max_low_pfn = end;
318 	}
319 
320 	if (min_low_pfn >= max_low_pfn)
321 		panic("Incorrect memory mapping !!!");
322 
323 	if (max_pfn > PFN_DOWN(HIGHMEM_START)) {
324 #ifdef CONFIG_HIGHMEM
325 		highstart_pfn = PFN_DOWN(HIGHMEM_START);
326 		highend_pfn = max_pfn;
327 #else
328 		max_low_pfn = PFN_DOWN(HIGHMEM_START);
329 		max_pfn = max_low_pfn;
330 #endif
331 	}
332 
333 	/*
334 	 * Reserve initrd memory if needed.
335 	 */
336 	finalize_initrd();
337 }
338 
339 #endif	/* CONFIG_SGI_IP27 */
340 
341 static int usermem __initdata;
342 
343 static int __init early_parse_mem(char *p)
344 {
345 	phys_addr_t start, size;
346 
347 	/*
348 	 * If a user specifies memory size, we
349 	 * blow away any automatically generated
350 	 * size.
351 	 */
352 	if (usermem == 0) {
353 		usermem = 1;
354 		memblock_remove(memblock_start_of_DRAM(),
355 			memblock_end_of_DRAM() - memblock_start_of_DRAM());
356 	}
357 	start = 0;
358 	size = memparse(p, &p);
359 	if (*p == '@')
360 		start = memparse(p + 1, &p);
361 
362 	memblock_add(start, size);
363 
364 	return 0;
365 }
366 early_param("mem", early_parse_mem);
367 
368 static int __init early_parse_memmap(char *p)
369 {
370 	char *oldp;
371 	u64 start_at, mem_size;
372 
373 	if (!p)
374 		return -EINVAL;
375 
376 	if (!strncmp(p, "exactmap", 8)) {
377 		pr_err("\"memmap=exactmap\" invalid on MIPS\n");
378 		return 0;
379 	}
380 
381 	oldp = p;
382 	mem_size = memparse(p, &p);
383 	if (p == oldp)
384 		return -EINVAL;
385 
386 	if (*p == '@') {
387 		start_at = memparse(p+1, &p);
388 		memblock_add(start_at, mem_size);
389 	} else if (*p == '#') {
390 		pr_err("\"memmap=nn#ss\" (force ACPI data) invalid on MIPS\n");
391 		return -EINVAL;
392 	} else if (*p == '$') {
393 		start_at = memparse(p+1, &p);
394 		memblock_add(start_at, mem_size);
395 		memblock_reserve(start_at, mem_size);
396 	} else {
397 		pr_err("\"memmap\" invalid format!\n");
398 		return -EINVAL;
399 	}
400 
401 	if (*p == '\0') {
402 		usermem = 1;
403 		return 0;
404 	} else
405 		return -EINVAL;
406 }
407 early_param("memmap", early_parse_memmap);
408 
409 #ifdef CONFIG_PROC_VMCORE
410 static unsigned long setup_elfcorehdr, setup_elfcorehdr_size;
411 static int __init early_parse_elfcorehdr(char *p)
412 {
413 	phys_addr_t start, end;
414 	u64 i;
415 
416 	setup_elfcorehdr = memparse(p, &p);
417 
418 	for_each_mem_range(i, &start, &end) {
419 		if (setup_elfcorehdr >= start && setup_elfcorehdr < end) {
420 			/*
421 			 * Reserve from the elf core header to the end of
422 			 * the memory segment, that should all be kdump
423 			 * reserved memory.
424 			 */
425 			setup_elfcorehdr_size = end - setup_elfcorehdr;
426 			break;
427 		}
428 	}
429 	/*
430 	 * If we don't find it in the memory map, then we shouldn't
431 	 * have to worry about it, as the new kernel won't use it.
432 	 */
433 	return 0;
434 }
435 early_param("elfcorehdr", early_parse_elfcorehdr);
436 #endif
437 
438 #ifdef CONFIG_KEXEC
439 
440 /* 64M alignment for crash kernel regions */
441 #define CRASH_ALIGN	SZ_64M
442 #define CRASH_ADDR_MAX	SZ_512M
443 
444 static void __init mips_parse_crashkernel(void)
445 {
446 	unsigned long long total_mem;
447 	unsigned long long crash_size, crash_base;
448 	int ret;
449 
450 	total_mem = memblock_phys_mem_size();
451 	ret = parse_crashkernel(boot_command_line, total_mem,
452 				&crash_size, &crash_base);
453 	if (ret != 0 || crash_size <= 0)
454 		return;
455 
456 	if (crash_base <= 0) {
457 		crash_base = memblock_find_in_range(CRASH_ALIGN, CRASH_ADDR_MAX,
458 							crash_size, CRASH_ALIGN);
459 		if (!crash_base) {
460 			pr_warn("crashkernel reservation failed - No suitable area found.\n");
461 			return;
462 		}
463 	} else {
464 		unsigned long long start;
465 
466 		start = memblock_find_in_range(crash_base, crash_base + crash_size,
467 						crash_size, 1);
468 		if (start != crash_base) {
469 			pr_warn("Invalid memory region reserved for crash kernel\n");
470 			return;
471 		}
472 	}
473 
474 	crashk_res.start = crash_base;
475 	crashk_res.end	 = crash_base + crash_size - 1;
476 }
477 
478 static void __init request_crashkernel(struct resource *res)
479 {
480 	int ret;
481 
482 	if (crashk_res.start == crashk_res.end)
483 		return;
484 
485 	ret = request_resource(res, &crashk_res);
486 	if (!ret)
487 		pr_info("Reserving %ldMB of memory at %ldMB for crashkernel\n",
488 			(unsigned long)(resource_size(&crashk_res) >> 20),
489 			(unsigned long)(crashk_res.start  >> 20));
490 }
491 #else /* !defined(CONFIG_KEXEC)		*/
492 static void __init mips_parse_crashkernel(void)
493 {
494 }
495 
496 static void __init request_crashkernel(struct resource *res)
497 {
498 }
499 #endif /* !defined(CONFIG_KEXEC)  */
500 
501 static void __init check_kernel_sections_mem(void)
502 {
503 	phys_addr_t start = __pa_symbol(&_text);
504 	phys_addr_t size = __pa_symbol(&_end) - start;
505 
506 	if (!memblock_is_region_memory(start, size)) {
507 		pr_info("Kernel sections are not in the memory maps\n");
508 		memblock_add(start, size);
509 	}
510 }
511 
512 static void __init bootcmdline_append(const char *s, size_t max)
513 {
514 	if (!s[0] || !max)
515 		return;
516 
517 	if (boot_command_line[0])
518 		strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
519 
520 	strlcat(boot_command_line, s, max);
521 }
522 
523 #ifdef CONFIG_OF_EARLY_FLATTREE
524 
525 static int __init bootcmdline_scan_chosen(unsigned long node, const char *uname,
526 					  int depth, void *data)
527 {
528 	bool *dt_bootargs = data;
529 	const char *p;
530 	int l;
531 
532 	if (depth != 1 || !data ||
533 	    (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
534 		return 0;
535 
536 	p = of_get_flat_dt_prop(node, "bootargs", &l);
537 	if (p != NULL && l > 0) {
538 		bootcmdline_append(p, min(l, COMMAND_LINE_SIZE));
539 		*dt_bootargs = true;
540 	}
541 
542 	return 1;
543 }
544 
545 #endif /* CONFIG_OF_EARLY_FLATTREE */
546 
547 static void __init bootcmdline_init(void)
548 {
549 	bool dt_bootargs = false;
550 
551 	/*
552 	 * If CMDLINE_OVERRIDE is enabled then initializing the command line is
553 	 * trivial - we simply use the built-in command line unconditionally &
554 	 * unmodified.
555 	 */
556 	if (IS_ENABLED(CONFIG_CMDLINE_OVERRIDE)) {
557 		strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
558 		return;
559 	}
560 
561 	/*
562 	 * If the user specified a built-in command line &
563 	 * MIPS_CMDLINE_BUILTIN_EXTEND, then the built-in command line is
564 	 * prepended to arguments from the bootloader or DT so we'll copy them
565 	 * to the start of boot_command_line here. Otherwise, empty
566 	 * boot_command_line to undo anything early_init_dt_scan_chosen() did.
567 	 */
568 	if (IS_ENABLED(CONFIG_MIPS_CMDLINE_BUILTIN_EXTEND))
569 		strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
570 	else
571 		boot_command_line[0] = 0;
572 
573 #ifdef CONFIG_OF_EARLY_FLATTREE
574 	/*
575 	 * If we're configured to take boot arguments from DT, look for those
576 	 * now.
577 	 */
578 	if (IS_ENABLED(CONFIG_MIPS_CMDLINE_FROM_DTB) ||
579 	    IS_ENABLED(CONFIG_MIPS_CMDLINE_DTB_EXTEND))
580 		of_scan_flat_dt(bootcmdline_scan_chosen, &dt_bootargs);
581 #endif
582 
583 	/*
584 	 * If we didn't get any arguments from DT (regardless of whether that's
585 	 * because we weren't configured to look for them, or because we looked
586 	 * & found none) then we'll take arguments from the bootloader.
587 	 * plat_mem_setup() should have filled arcs_cmdline with arguments from
588 	 * the bootloader.
589 	 */
590 	if (IS_ENABLED(CONFIG_MIPS_CMDLINE_DTB_EXTEND) || !dt_bootargs)
591 		bootcmdline_append(arcs_cmdline, COMMAND_LINE_SIZE);
592 
593 	/*
594 	 * If the user specified a built-in command line & we didn't already
595 	 * prepend it, we append it to boot_command_line here.
596 	 */
597 	if (IS_ENABLED(CONFIG_CMDLINE_BOOL) &&
598 	    !IS_ENABLED(CONFIG_MIPS_CMDLINE_BUILTIN_EXTEND))
599 		bootcmdline_append(builtin_cmdline, COMMAND_LINE_SIZE);
600 }
601 
602 /*
603  * arch_mem_init - initialize memory management subsystem
604  *
605  *  o plat_mem_setup() detects the memory configuration and will record detected
606  *    memory areas using memblock_add.
607  *
608  * At this stage the memory configuration of the system is known to the
609  * kernel but generic memory management system is still entirely uninitialized.
610  *
611  *  o bootmem_init()
612  *  o sparse_init()
613  *  o paging_init()
614  *  o dma_contiguous_reserve()
615  *
616  * At this stage the bootmem allocator is ready to use.
617  *
618  * NOTE: historically plat_mem_setup did the entire platform initialization.
619  *	 This was rather impractical because it meant plat_mem_setup had to
620  * get away without any kind of memory allocator.  To keep old code from
621  * breaking plat_setup was just renamed to plat_mem_setup and a second platform
622  * initialization hook for anything else was introduced.
623  */
624 static void __init arch_mem_init(char **cmdline_p)
625 {
626 	/* call board setup routine */
627 	plat_mem_setup();
628 	memblock_set_bottom_up(true);
629 
630 	bootcmdline_init();
631 	strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
632 	*cmdline_p = command_line;
633 
634 	parse_early_param();
635 
636 	if (usermem)
637 		pr_info("User-defined physical RAM map overwrite\n");
638 
639 	check_kernel_sections_mem();
640 
641 	early_init_fdt_reserve_self();
642 	early_init_fdt_scan_reserved_mem();
643 
644 #ifndef CONFIG_NUMA
645 	memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
646 #endif
647 	bootmem_init();
648 
649 	/*
650 	 * Prevent memblock from allocating high memory.
651 	 * This cannot be done before max_low_pfn is detected, so up
652 	 * to this point is possible to only reserve physical memory
653 	 * with memblock_reserve; memblock_alloc* can be used
654 	 * only after this point
655 	 */
656 	memblock_set_current_limit(PFN_PHYS(max_low_pfn));
657 
658 #ifdef CONFIG_PROC_VMCORE
659 	if (setup_elfcorehdr && setup_elfcorehdr_size) {
660 		printk(KERN_INFO "kdump reserved memory at %lx-%lx\n",
661 		       setup_elfcorehdr, setup_elfcorehdr_size);
662 		memblock_reserve(setup_elfcorehdr, setup_elfcorehdr_size);
663 	}
664 #endif
665 
666 	mips_parse_crashkernel();
667 #ifdef CONFIG_KEXEC
668 	if (crashk_res.start != crashk_res.end)
669 		memblock_reserve(crashk_res.start, resource_size(&crashk_res));
670 #endif
671 	device_tree_init();
672 
673 	/*
674 	 * In order to reduce the possibility of kernel panic when failed to
675 	 * get IO TLB memory under CONFIG_SWIOTLB, it is better to allocate
676 	 * low memory as small as possible before plat_swiotlb_setup(), so
677 	 * make sparse_init() using top-down allocation.
678 	 */
679 	memblock_set_bottom_up(false);
680 	sparse_init();
681 	memblock_set_bottom_up(true);
682 
683 	plat_swiotlb_setup();
684 
685 	dma_contiguous_reserve(PFN_PHYS(max_low_pfn));
686 
687 	/* Reserve for hibernation. */
688 	memblock_reserve(__pa_symbol(&__nosave_begin),
689 		__pa_symbol(&__nosave_end) - __pa_symbol(&__nosave_begin));
690 
691 	early_memtest(PFN_PHYS(ARCH_PFN_OFFSET), PFN_PHYS(max_low_pfn));
692 }
693 
694 static void __init resource_init(void)
695 {
696 	phys_addr_t start, end;
697 	u64 i;
698 
699 	if (UNCAC_BASE != IO_BASE)
700 		return;
701 
702 	code_resource.start = __pa_symbol(&_text);
703 	code_resource.end = __pa_symbol(&_etext) - 1;
704 	data_resource.start = __pa_symbol(&_etext);
705 	data_resource.end = __pa_symbol(&_edata) - 1;
706 	bss_resource.start = __pa_symbol(&__bss_start);
707 	bss_resource.end = __pa_symbol(&__bss_stop) - 1;
708 
709 	for_each_mem_range(i, &start, &end) {
710 		struct resource *res;
711 
712 		res = memblock_alloc(sizeof(struct resource), SMP_CACHE_BYTES);
713 		if (!res)
714 			panic("%s: Failed to allocate %zu bytes\n", __func__,
715 			      sizeof(struct resource));
716 
717 		res->start = start;
718 		/*
719 		 * In memblock, end points to the first byte after the
720 		 * range while in resourses, end points to the last byte in
721 		 * the range.
722 		 */
723 		res->end = end - 1;
724 		res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
725 		res->name = "System RAM";
726 
727 		request_resource(&iomem_resource, res);
728 
729 		/*
730 		 *  We don't know which RAM region contains kernel data,
731 		 *  so we try it repeatedly and let the resource manager
732 		 *  test it.
733 		 */
734 		request_resource(res, &code_resource);
735 		request_resource(res, &data_resource);
736 		request_resource(res, &bss_resource);
737 		request_crashkernel(res);
738 	}
739 }
740 
741 #ifdef CONFIG_SMP
742 static void __init prefill_possible_map(void)
743 {
744 	int i, possible = num_possible_cpus();
745 
746 	if (possible > nr_cpu_ids)
747 		possible = nr_cpu_ids;
748 
749 	for (i = 0; i < possible; i++)
750 		set_cpu_possible(i, true);
751 	for (; i < NR_CPUS; i++)
752 		set_cpu_possible(i, false);
753 
754 	nr_cpu_ids = possible;
755 }
756 #else
757 static inline void prefill_possible_map(void) {}
758 #endif
759 
760 void __init setup_arch(char **cmdline_p)
761 {
762 	cpu_probe();
763 	mips_cm_probe();
764 	prom_init();
765 
766 	setup_early_fdc_console();
767 #ifdef CONFIG_EARLY_PRINTK
768 	setup_early_printk();
769 #endif
770 	cpu_report();
771 	check_bugs_early();
772 
773 #if defined(CONFIG_VT)
774 #if defined(CONFIG_VGA_CONSOLE)
775 	conswitchp = &vga_con;
776 #endif
777 #endif
778 
779 	arch_mem_init(cmdline_p);
780 	dmi_setup();
781 
782 	resource_init();
783 	plat_smp_setup();
784 	prefill_possible_map();
785 
786 	cpu_cache_init();
787 	paging_init();
788 
789 	memblock_dump_all();
790 }
791 
792 unsigned long kernelsp[NR_CPUS];
793 unsigned long fw_arg0, fw_arg1, fw_arg2, fw_arg3;
794 
795 #ifdef CONFIG_DEBUG_FS
796 struct dentry *mips_debugfs_dir;
797 static int __init debugfs_mips(void)
798 {
799 	mips_debugfs_dir = debugfs_create_dir("mips", NULL);
800 	return 0;
801 }
802 arch_initcall(debugfs_mips);
803 #endif
804 
805 #ifdef CONFIG_DMA_MAYBE_COHERENT
806 bool dma_default_coherent;
807 EXPORT_SYMBOL_GPL(dma_default_coherent);
808 
809 static int __init setcoherentio(char *str)
810 {
811 	dma_default_coherent = true;
812 	pr_info("Hardware DMA cache coherency (command line)\n");
813 	return 0;
814 }
815 early_param("coherentio", setcoherentio);
816 
817 static int __init setnocoherentio(char *str)
818 {
819 	dma_default_coherent = true;
820 	pr_info("Software DMA cache coherency (command line)\n");
821 	return 0;
822 }
823 early_param("nocoherentio", setnocoherentio);
824 #endif
825