xref: /linux/arch/mips/kernel/setup.c (revision e2683c8868d03382da7e1ce8453b543a043066d1)
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/cpu.h>
15 #include <linux/delay.h>
16 #include <linux/hex.h>
17 #include <linux/ioport.h>
18 #include <linux/export.h>
19 #include <linux/memblock.h>
20 #include <linux/initrd.h>
21 #include <linux/root_dev.h>
22 #include <linux/highmem.h>
23 #include <linux/console.h>
24 #include <linux/pfn.h>
25 #include <linux/debugfs.h>
26 #include <linux/kexec.h>
27 #include <linux/sizes.h>
28 #include <linux/device.h>
29 #include <linux/dma-map-ops.h>
30 #include <linux/decompress/generic.h>
31 #include <linux/of_fdt.h>
32 #include <linux/dmi.h>
33 #include <linux/crash_dump.h>
34 #include <linux/string.h>
35 
36 #include <asm/addrspace.h>
37 #include <asm/bootinfo.h>
38 #include <asm/bugs.h>
39 #include <asm/cache.h>
40 #include <asm/cdmm.h>
41 #include <asm/cpu.h>
42 #include <asm/debug.h>
43 #include <asm/mmzone.h>
44 #include <asm/sections.h>
45 #include <asm/setup.h>
46 #include <asm/smp-ops.h>
47 #include <asm/mips-cps.h>
48 #include <asm/prom.h>
49 #include <asm/fw/fw.h>
50 
51 #ifdef CONFIG_MIPS_ELF_APPENDED_DTB
52 char __section(".appended_dtb") __appended_dtb[0x100000];
53 #endif /* CONFIG_MIPS_ELF_APPENDED_DTB */
54 
55 struct cpuinfo_mips cpu_data[NR_CPUS] __read_mostly;
56 
57 EXPORT_SYMBOL(cpu_data);
58 
59 /*
60  * Setup information
61  *
62  * These are initialized so they are in the .data section
63  */
64 unsigned long mips_machtype __read_mostly = MACH_UNKNOWN;
65 
66 EXPORT_SYMBOL(mips_machtype);
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 const char builtin_cmdline[] __initconst = CONFIG_CMDLINE;
73 #else
74 static const char builtin_cmdline[] __initconst = "";
75 #endif
76 
77 /*
78  * mips_io_port_base is the begin of the address space to which x86 style
79  * I/O ports are mapped.
80  */
81 unsigned long mips_io_port_base = -1;
82 EXPORT_SYMBOL(mips_io_port_base);
83 
84 static struct resource code_resource = { .name = "Kernel code", };
85 static struct resource data_resource = { .name = "Kernel data", };
86 static struct resource bss_resource = { .name = "Kernel bss", };
87 
88 unsigned long __kaslr_offset __ro_after_init;
89 EXPORT_SYMBOL(__kaslr_offset);
90 
91 static void *detect_magic __initdata = detect_memory_region;
92 
93 #ifdef CONFIG_MIPS_AUTO_PFN_OFFSET
94 unsigned long ARCH_PFN_OFFSET;
95 EXPORT_SYMBOL(ARCH_PFN_OFFSET);
96 #endif
97 
98 void __init detect_memory_region(phys_addr_t start, phys_addr_t sz_min, phys_addr_t sz_max)
99 {
100 	void *dm = &detect_magic;
101 	phys_addr_t size;
102 
103 	for (size = sz_min; size < sz_max; size <<= 1) {
104 		if (!memcmp(dm, dm + size, sizeof(detect_magic)))
105 			break;
106 	}
107 
108 	pr_debug("Memory: %lluMB of RAM detected at 0x%llx (min: %lluMB, max: %lluMB)\n",
109 		((unsigned long long) size) / SZ_1M,
110 		(unsigned long long) start,
111 		((unsigned long long) sz_min) / SZ_1M,
112 		((unsigned long long) sz_max) / SZ_1M);
113 
114 	memblock_add(start, size);
115 }
116 
117 /*
118  * Manage initrd
119  */
120 #ifdef CONFIG_BLK_DEV_INITRD
121 
122 static int __init rd_start_early(char *p)
123 {
124 	unsigned long start = memparse(p, &p);
125 
126 #ifdef CONFIG_64BIT
127 	/* Guess if the sign extension was forgotten by bootloader */
128 	if (start < XKPHYS)
129 		start = (int)start;
130 #endif
131 	initrd_start = start;
132 	initrd_end += start;
133 	return 0;
134 }
135 early_param("rd_start", rd_start_early);
136 
137 static int __init rd_size_early(char *p)
138 {
139 	initrd_end += memparse(p, &p);
140 	return 0;
141 }
142 early_param("rd_size", rd_size_early);
143 
144 /* it returns the next free pfn after initrd */
145 static unsigned long __init init_initrd(void)
146 {
147 	unsigned long end;
148 
149 	/*
150 	 * Board specific code or command line parser should have
151 	 * already set up initrd_start and initrd_end. In these cases
152 	 * perform sanity checks and use them if all looks good.
153 	 */
154 	if (!initrd_start || initrd_end <= initrd_start)
155 		goto disable;
156 
157 	if (initrd_start & ~PAGE_MASK) {
158 		pr_err("initrd start must be page aligned\n");
159 		goto disable;
160 	}
161 
162 	/*
163 	 * Sanitize initrd addresses. For example firmware
164 	 * can't guess if they need to pass them through
165 	 * 64-bits values if the kernel has been built in pure
166 	 * 32-bit. We need also to switch from KSEG0 to XKPHYS
167 	 * addresses now, so the code can now safely use __pa().
168 	 */
169 	end = __pa(initrd_end);
170 	initrd_end = (unsigned long)__va(end);
171 	initrd_start = (unsigned long)__va(__pa(initrd_start));
172 
173 	if (initrd_start < PAGE_OFFSET) {
174 		pr_err("initrd start < PAGE_OFFSET\n");
175 		goto disable;
176 	}
177 
178 	ROOT_DEV = Root_RAM0;
179 	return PFN_UP(end);
180 disable:
181 	initrd_start = 0;
182 	initrd_end = 0;
183 	return 0;
184 }
185 
186 /* In some conditions (e.g. big endian bootloader with a little endian
187    kernel), the initrd might appear byte swapped.  Try to detect this and
188    byte swap it if needed.  */
189 static void __init maybe_bswap_initrd(void)
190 {
191 #if defined(CONFIG_CPU_CAVIUM_OCTEON)
192 	u64 buf;
193 
194 	/* Check for CPIO signature */
195 	if (!memcmp((void *)initrd_start, "070701", 6))
196 		return;
197 
198 	/* Check for compressed initrd */
199 	if (decompress_method((unsigned char *)initrd_start, 8, NULL))
200 		return;
201 
202 	/* Try again with a byte swapped header */
203 	buf = swab64p((u64 *)initrd_start);
204 	if (!memcmp(&buf, "070701", 6) ||
205 	    decompress_method((unsigned char *)(&buf), 8, NULL)) {
206 		unsigned long i;
207 
208 		pr_info("Byteswapped initrd detected\n");
209 		for (i = initrd_start; i < ALIGN(initrd_end, 8); i += 8)
210 			swab64s((u64 *)i);
211 	}
212 #endif
213 }
214 
215 static void __init finalize_initrd(void)
216 {
217 	unsigned long size = initrd_end - initrd_start;
218 
219 	if (size == 0) {
220 		printk(KERN_INFO "Initrd not found or empty");
221 		goto disable;
222 	}
223 	if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
224 		printk(KERN_ERR "Initrd extends beyond end of memory");
225 		goto disable;
226 	}
227 
228 	maybe_bswap_initrd();
229 
230 	memblock_reserve(__pa(initrd_start), size);
231 	initrd_below_start_ok = 1;
232 
233 	pr_info("Initial ramdisk at: 0x%lx (%lu bytes)\n",
234 		initrd_start, size);
235 	return;
236 disable:
237 	printk(KERN_CONT " - disabling initrd\n");
238 	initrd_start = 0;
239 	initrd_end = 0;
240 }
241 
242 #else  /* !CONFIG_BLK_DEV_INITRD */
243 
244 static unsigned long __init init_initrd(void)
245 {
246 	return 0;
247 }
248 
249 #define finalize_initrd()	do {} while (0)
250 
251 #endif
252 
253 /*
254  * Initialize the bootmem allocator. It also setup initrd related data
255  * if needed.
256  */
257 #if defined(CONFIG_SGI_IP27) || (defined(CONFIG_CPU_LOONGSON64) && defined(CONFIG_NUMA))
258 
259 static void __init bootmem_init(void)
260 {
261 	init_initrd();
262 	finalize_initrd();
263 }
264 
265 #else  /* !CONFIG_SGI_IP27 */
266 
267 static void __init bootmem_init(void)
268 {
269 	phys_addr_t ramstart, ramend;
270 	unsigned long start, end;
271 	int i;
272 
273 	ramstart = memblock_start_of_DRAM();
274 	ramend = memblock_end_of_DRAM();
275 
276 	/*
277 	 * Sanity check any INITRD first. We don't take it into account
278 	 * for bootmem setup initially, rely on the end-of-kernel-code
279 	 * as our memory range starting point. Once bootmem is inited we
280 	 * will reserve the area used for the initrd.
281 	 */
282 	init_initrd();
283 
284 	/* Reserve memory occupied by kernel. */
285 	memblock_reserve(__pa_symbol(&_text),
286 			__pa_symbol(&_end) - __pa_symbol(&_text));
287 
288 	/* max_low_pfn is not a number of pages but the end pfn of low mem */
289 
290 #ifdef CONFIG_MIPS_AUTO_PFN_OFFSET
291 	ARCH_PFN_OFFSET = PFN_UP(ramstart);
292 #else
293 	/*
294 	 * Reserve any memory between the start of RAM and PHYS_OFFSET
295 	 */
296 	if (ramstart > PHYS_OFFSET)
297 		memblock_reserve(PHYS_OFFSET, ramstart - PHYS_OFFSET);
298 
299 	if (PFN_UP(ramstart) > ARCH_PFN_OFFSET) {
300 		pr_info("Wasting %lu bytes for tracking %lu unused pages\n",
301 			(unsigned long)((PFN_UP(ramstart) - ARCH_PFN_OFFSET) * sizeof(struct page)),
302 			(unsigned long)(PFN_UP(ramstart) - ARCH_PFN_OFFSET));
303 	}
304 #endif
305 
306 	min_low_pfn = ARCH_PFN_OFFSET;
307 	max_pfn = PFN_DOWN(ramend);
308 	for_each_mem_pfn_range(i, MAX_NUMNODES, &start, &end, NULL) {
309 		/*
310 		 * Skip highmem here so we get an accurate max_low_pfn if low
311 		 * memory stops short of high memory.
312 		 * If the region overlaps HIGHMEM_START, end is clipped so
313 		 * max_pfn excludes the highmem portion.
314 		 */
315 		if (start >= PFN_DOWN(HIGHMEM_START))
316 			continue;
317 		if (end > PFN_DOWN(HIGHMEM_START))
318 			end = PFN_DOWN(HIGHMEM_START);
319 		if (end > max_low_pfn)
320 			max_low_pfn = end;
321 	}
322 
323 	if (min_low_pfn >= max_low_pfn)
324 		panic("Incorrect memory mapping !!!");
325 
326 	if (max_pfn > PFN_DOWN(HIGHMEM_START)) {
327 		max_low_pfn = PFN_DOWN(HIGHMEM_START);
328 #ifdef CONFIG_HIGHMEM
329 		highstart_pfn = max_low_pfn;
330 		highend_pfn = max_pfn;
331 #else
332 		max_pfn = max_low_pfn;
333 #endif
334 	}
335 
336 	/*
337 	 * Reserve initrd memory if needed.
338 	 */
339 	finalize_initrd();
340 }
341 
342 #endif	/* CONFIG_SGI_IP27 */
343 
344 static int usermem __initdata;
345 
346 static int __init early_parse_mem(char *p)
347 {
348 	phys_addr_t start, size;
349 
350 	if (!p) {
351 		pr_err("mem parameter is empty, do nothing\n");
352 		return -EINVAL;
353 	}
354 
355 	/*
356 	 * If a user specifies memory size, we
357 	 * blow away any automatically generated
358 	 * size.
359 	 */
360 	if (usermem == 0) {
361 		usermem = 1;
362 		memblock_remove(memblock_start_of_DRAM(),
363 			memblock_end_of_DRAM() - memblock_start_of_DRAM());
364 	}
365 	start = 0;
366 	size = memparse(p, &p);
367 	if (*p == '@')
368 		start = memparse(p + 1, &p);
369 
370 	if (IS_ENABLED(CONFIG_NUMA))
371 		memblock_add_node(start, size, pa_to_nid(start), MEMBLOCK_NONE);
372 	else
373 		memblock_add(start, size);
374 
375 	return 0;
376 }
377 early_param("mem", early_parse_mem);
378 
379 static int __init early_parse_memmap(char *p)
380 {
381 	char *oldp;
382 	u64 start_at, mem_size;
383 
384 	if (!p)
385 		return -EINVAL;
386 
387 	if (!strncmp(p, "exactmap", 8)) {
388 		pr_err("\"memmap=exactmap\" invalid on MIPS\n");
389 		return 0;
390 	}
391 
392 	oldp = p;
393 	mem_size = memparse(p, &p);
394 	if (p == oldp)
395 		return -EINVAL;
396 
397 	if (*p == '@') {
398 		start_at = memparse(p+1, &p);
399 		memblock_add(start_at, mem_size);
400 	} else if (*p == '#') {
401 		pr_err("\"memmap=nn#ss\" (force ACPI data) invalid on MIPS\n");
402 		return -EINVAL;
403 	} else if (*p == '$') {
404 		start_at = memparse(p+1, &p);
405 		memblock_add(start_at, mem_size);
406 		memblock_reserve(start_at, mem_size);
407 	} else {
408 		pr_err("\"memmap\" invalid format!\n");
409 		return -EINVAL;
410 	}
411 
412 	if (*p == '\0') {
413 		usermem = 1;
414 		return 0;
415 	} else
416 		return -EINVAL;
417 }
418 early_param("memmap", early_parse_memmap);
419 
420 static void __init mips_reserve_vmcore(void)
421 {
422 #ifdef CONFIG_PROC_VMCORE
423 	phys_addr_t start, end;
424 	u64 i;
425 
426 	if (!elfcorehdr_size) {
427 		for_each_mem_range(i, &start, &end) {
428 			if (elfcorehdr_addr >= start && elfcorehdr_addr < end) {
429 				/*
430 				 * Reserve from the elf core header to the end of
431 				 * the memory segment, that should all be kdump
432 				 * reserved memory.
433 				 */
434 				elfcorehdr_size = end - elfcorehdr_addr;
435 				break;
436 			}
437 		}
438 	}
439 
440 	pr_info("Reserving %ldKB of memory at %ldKB for kdump\n",
441 		(unsigned long)elfcorehdr_size >> 10, (unsigned long)elfcorehdr_addr >> 10);
442 
443 	memblock_reserve(elfcorehdr_addr, elfcorehdr_size);
444 #endif
445 }
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 	if (!IS_ENABLED(CONFIG_CRASH_RESERVE))
458 		return;
459 
460 	total_mem = memblock_phys_mem_size();
461 	ret = parse_crashkernel(boot_command_line, total_mem,
462 				&crash_size, &crash_base,
463 				NULL, NULL, NULL);
464 	if (ret != 0 || crash_size <= 0)
465 		return;
466 
467 	if (crash_base <= 0) {
468 		crash_base = memblock_phys_alloc_range(crash_size, CRASH_ALIGN,
469 						       CRASH_ALIGN,
470 						       CRASH_ADDR_MAX);
471 		if (!crash_base) {
472 			pr_warn("crashkernel reservation failed - No suitable area found.\n");
473 			return;
474 		}
475 	} else {
476 		unsigned long long start;
477 
478 		start = memblock_phys_alloc_range(crash_size, 1,
479 						  crash_base,
480 						  crash_base + crash_size);
481 		if (start != crash_base) {
482 			pr_warn("Invalid memory region reserved for crash kernel\n");
483 			return;
484 		}
485 	}
486 
487 	crashk_res.start = crash_base;
488 	crashk_res.end	 = crash_base + crash_size - 1;
489 }
490 
491 static void __init request_crashkernel(struct resource *res)
492 {
493 	int ret;
494 
495 	if (!IS_ENABLED(CONFIG_CRASH_RESERVE))
496 		return;
497 
498 	if (crashk_res.start == crashk_res.end)
499 		return;
500 
501 	ret = request_resource(res, &crashk_res);
502 	if (!ret)
503 		pr_info("Reserving %ldMB of memory at %ldMB for crashkernel\n",
504 			(unsigned long)(resource_size(&crashk_res) >> 20),
505 			(unsigned long)(crashk_res.start  >> 20));
506 }
507 
508 static void __init check_kernel_sections_mem(void)
509 {
510 	phys_addr_t start = __pa_symbol(&_text);
511 	phys_addr_t size = __pa_symbol(&_end) - start;
512 
513 	if (!memblock_is_region_memory(start, size)) {
514 		pr_info("Kernel sections are not in the memory maps\n");
515 		memblock_add(start, size);
516 	}
517 }
518 
519 static void __init bootcmdline_append(const char *s, size_t max)
520 {
521 	if (!s[0] || !max)
522 		return;
523 
524 	if (boot_command_line[0])
525 		strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
526 
527 	strlcat(boot_command_line, s, max);
528 }
529 
530 #ifdef CONFIG_OF_EARLY_FLATTREE
531 
532 static int __init bootcmdline_scan_chosen(unsigned long node, const char *uname,
533 					  int depth, void *data)
534 {
535 	bool *dt_bootargs = data;
536 	const char *p;
537 	int l;
538 
539 	if (depth != 1 || !data ||
540 	    (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
541 		return 0;
542 
543 	p = of_get_flat_dt_prop(node, "bootargs", &l);
544 	if (p != NULL && l > 0) {
545 		if (strnlen(p, l) >= l)
546 			return 1;
547 
548 		bootcmdline_append(p, min(l, COMMAND_LINE_SIZE));
549 		*dt_bootargs = true;
550 	}
551 
552 	return 1;
553 }
554 
555 #endif /* CONFIG_OF_EARLY_FLATTREE */
556 
557 static void __init bootcmdline_init(void)
558 {
559 	bool dt_bootargs = false;
560 
561 	/*
562 	 * If CMDLINE_OVERRIDE is enabled then initializing the command line is
563 	 * trivial - we simply use the built-in command line unconditionally &
564 	 * unmodified.
565 	 */
566 	if (IS_ENABLED(CONFIG_CMDLINE_OVERRIDE)) {
567 		strscpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
568 		return;
569 	}
570 
571 	/*
572 	 * If the user specified a built-in command line &
573 	 * MIPS_CMDLINE_BUILTIN_EXTEND, then the built-in command line is
574 	 * prepended to arguments from the bootloader or DT so we'll copy them
575 	 * to the start of boot_command_line here. Otherwise, empty
576 	 * boot_command_line to undo anything early_init_dt_scan_chosen() did.
577 	 */
578 	if (IS_ENABLED(CONFIG_MIPS_CMDLINE_BUILTIN_EXTEND))
579 		strscpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
580 	else
581 		boot_command_line[0] = 0;
582 
583 #ifdef CONFIG_OF_EARLY_FLATTREE
584 	/*
585 	 * If we're configured to take boot arguments from DT, look for those
586 	 * now.
587 	 */
588 	if (IS_ENABLED(CONFIG_MIPS_CMDLINE_FROM_DTB) ||
589 	    IS_ENABLED(CONFIG_MIPS_CMDLINE_DTB_EXTEND))
590 		of_scan_flat_dt(bootcmdline_scan_chosen, &dt_bootargs);
591 #endif
592 
593 	/*
594 	 * If we didn't get any arguments from DT (regardless of whether that's
595 	 * because we weren't configured to look for them, or because we looked
596 	 * & found none) then we'll take arguments from the bootloader.
597 	 * plat_mem_setup() should have filled arcs_cmdline with arguments from
598 	 * the bootloader.
599 	 */
600 	if (IS_ENABLED(CONFIG_MIPS_CMDLINE_DTB_EXTEND) || !dt_bootargs)
601 		bootcmdline_append(arcs_cmdline, COMMAND_LINE_SIZE);
602 
603 	/*
604 	 * If the user specified a built-in command line & we didn't already
605 	 * prepend it, we append it to boot_command_line here.
606 	 */
607 	if (IS_ENABLED(CONFIG_CMDLINE_BOOL) &&
608 	    !IS_ENABLED(CONFIG_MIPS_CMDLINE_BUILTIN_EXTEND))
609 		bootcmdline_append(builtin_cmdline, COMMAND_LINE_SIZE);
610 }
611 
612 /*
613  * arch_mem_init - initialize memory management subsystem
614  *
615  *  o plat_mem_setup() detects the memory configuration and will record detected
616  *    memory areas using memblock_add.
617  *
618  * At this stage the memory configuration of the system is known to the
619  * kernel but generic memory management system is still entirely uninitialized.
620  *
621  *  o bootmem_init()
622  *  o pagetable_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 	plat_swiotlb_setup();
673 
674 	dma_contiguous_reserve(PFN_PHYS(max_low_pfn));
675 
676 	/* Reserve for hibernation. */
677 	memblock_reserve(__pa_symbol(&__nosave_begin),
678 		__pa_symbol(&__nosave_end) - __pa_symbol(&__nosave_begin));
679 
680 	early_memtest(PFN_PHYS(ARCH_PFN_OFFSET), PFN_PHYS(max_low_pfn));
681 }
682 
683 static void __init resource_init(void)
684 {
685 	phys_addr_t start, end;
686 	u64 i;
687 
688 	if (UNCAC_BASE != IO_BASE)
689 		return;
690 
691 	code_resource.start = __pa_symbol(&_text);
692 	code_resource.end = __pa_symbol(&_etext) - 1;
693 	data_resource.start = __pa_symbol(&_etext);
694 	data_resource.end = __pa_symbol(&_edata) - 1;
695 	bss_resource.start = __pa_symbol(&__bss_start);
696 	bss_resource.end = __pa_symbol(&__bss_stop) - 1;
697 
698 	for_each_mem_range(i, &start, &end) {
699 		struct resource *res;
700 
701 		res = memblock_alloc_or_panic(sizeof(struct resource), SMP_CACHE_BYTES);
702 
703 		res->start = start;
704 		/*
705 		 * In memblock, end points to the first byte after the
706 		 * range while in resourses, end points to the last byte in
707 		 * the range.
708 		 */
709 		res->end = end - 1;
710 		res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
711 		res->name = "System RAM";
712 
713 		request_resource(&iomem_resource, res);
714 
715 		/*
716 		 *  We don't know which RAM region contains kernel data,
717 		 *  so we try it repeatedly and let the resource manager
718 		 *  test it.
719 		 */
720 		request_resource(res, &code_resource);
721 		request_resource(res, &data_resource);
722 		request_resource(res, &bss_resource);
723 		request_crashkernel(res);
724 	}
725 }
726 
727 #ifdef CONFIG_SMP
728 static void __init prefill_possible_map(void)
729 {
730 	int i, possible = num_possible_cpus();
731 
732 	if (possible > nr_cpu_ids)
733 		possible = nr_cpu_ids;
734 
735 	for (i = 0; i < possible; i++)
736 		set_cpu_possible(i, true);
737 	for (; i < NR_CPUS; i++)
738 		set_cpu_possible(i, false);
739 
740 	set_nr_cpu_ids(possible);
741 }
742 #else
743 static inline void prefill_possible_map(void) {}
744 #endif
745 
746 static void __init setup_rng_seed(void)
747 {
748 	char *rng_seed_hex = fw_getenv("rngseed");
749 	u8 rng_seed[512];
750 	size_t len;
751 
752 	if (!rng_seed_hex)
753 		return;
754 
755 	len = min(sizeof(rng_seed), strlen(rng_seed_hex) / 2);
756 	if (hex2bin(rng_seed, rng_seed_hex, len))
757 		return;
758 
759 	add_bootloader_randomness(rng_seed, len);
760 	memzero_explicit(rng_seed, len);
761 	memzero_explicit(rng_seed_hex, len * 2);
762 }
763 
764 void __init setup_arch(char **cmdline_p)
765 {
766 	cpu_probe();
767 	mips_cm_probe();
768 	prom_init();
769 
770 	setup_early_fdc_console();
771 #ifdef CONFIG_EARLY_PRINTK
772 	setup_early_printk();
773 #endif
774 	cpu_report();
775 	if (IS_ENABLED(CONFIG_CPU_R4X00_BUGS64))
776 		check_bugs64_early();
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 	pagetable_init();
787 
788 	memblock_dump_all();
789 
790 	setup_rng_seed();
791 }
792 
793 unsigned long kernelsp[NR_CPUS];
794 unsigned long fw_arg0, fw_arg1, fw_arg2, fw_arg3;
795 
796 #ifdef CONFIG_DEBUG_FS
797 struct dentry *mips_debugfs_dir;
798 static int __init debugfs_mips(void)
799 {
800 	mips_debugfs_dir = debugfs_create_dir("mips", NULL);
801 	return 0;
802 }
803 arch_initcall(debugfs_mips);
804 #endif
805 
806 #ifdef CONFIG_DMA_NONCOHERENT
807 static int __init setcoherentio(char *str)
808 {
809 	dma_default_coherent = true;
810 	pr_info("Hardware DMA cache coherency (command line)\n");
811 	return 0;
812 }
813 early_param("coherentio", setcoherentio);
814 
815 static int __init setnocoherentio(char *str)
816 {
817 	dma_default_coherent = false;
818 	pr_info("Software DMA cache coherency (command line)\n");
819 	return 0;
820 }
821 early_param("nocoherentio", setnocoherentio);
822 #endif
823 
824 void __init arch_cpu_finalize_init(void)
825 {
826 	unsigned int cpu = smp_processor_id();
827 
828 	cpu_data[cpu].udelay_val = loops_per_jiffy;
829 	check_bugs32();
830 
831 	if (IS_ENABLED(CONFIG_CPU_R4X00_BUGS64))
832 		check_bugs64();
833 }
834