xref: /linux/arch/arm/kernel/setup.c (revision e0bf6c5ca2d3281f231c5f0c9bf145e9513644de)
1 /*
2  *  linux/arch/arm/kernel/setup.c
3  *
4  *  Copyright (C) 1995-2001 Russell King
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 #include <linux/export.h>
11 #include <linux/kernel.h>
12 #include <linux/stddef.h>
13 #include <linux/ioport.h>
14 #include <linux/delay.h>
15 #include <linux/utsname.h>
16 #include <linux/initrd.h>
17 #include <linux/console.h>
18 #include <linux/bootmem.h>
19 #include <linux/seq_file.h>
20 #include <linux/screen_info.h>
21 #include <linux/of_iommu.h>
22 #include <linux/of_platform.h>
23 #include <linux/init.h>
24 #include <linux/kexec.h>
25 #include <linux/of_fdt.h>
26 #include <linux/cpu.h>
27 #include <linux/interrupt.h>
28 #include <linux/smp.h>
29 #include <linux/proc_fs.h>
30 #include <linux/memblock.h>
31 #include <linux/bug.h>
32 #include <linux/compiler.h>
33 #include <linux/sort.h>
34 
35 #include <asm/unified.h>
36 #include <asm/cp15.h>
37 #include <asm/cpu.h>
38 #include <asm/cputype.h>
39 #include <asm/elf.h>
40 #include <asm/procinfo.h>
41 #include <asm/psci.h>
42 #include <asm/sections.h>
43 #include <asm/setup.h>
44 #include <asm/smp_plat.h>
45 #include <asm/mach-types.h>
46 #include <asm/cacheflush.h>
47 #include <asm/cachetype.h>
48 #include <asm/tlbflush.h>
49 
50 #include <asm/prom.h>
51 #include <asm/mach/arch.h>
52 #include <asm/mach/irq.h>
53 #include <asm/mach/time.h>
54 #include <asm/system_info.h>
55 #include <asm/system_misc.h>
56 #include <asm/traps.h>
57 #include <asm/unwind.h>
58 #include <asm/memblock.h>
59 #include <asm/virt.h>
60 
61 #include "atags.h"
62 
63 
64 #if defined(CONFIG_FPE_NWFPE) || defined(CONFIG_FPE_FASTFPE)
65 char fpe_type[8];
66 
67 static int __init fpe_setup(char *line)
68 {
69 	memcpy(fpe_type, line, 8);
70 	return 1;
71 }
72 
73 __setup("fpe=", fpe_setup);
74 #endif
75 
76 extern void init_default_cache_policy(unsigned long);
77 extern void paging_init(const struct machine_desc *desc);
78 extern void early_paging_init(const struct machine_desc *,
79 			      struct proc_info_list *);
80 extern void sanity_check_meminfo(void);
81 extern enum reboot_mode reboot_mode;
82 extern void setup_dma_zone(const struct machine_desc *desc);
83 
84 unsigned int processor_id;
85 EXPORT_SYMBOL(processor_id);
86 unsigned int __machine_arch_type __read_mostly;
87 EXPORT_SYMBOL(__machine_arch_type);
88 unsigned int cacheid __read_mostly;
89 EXPORT_SYMBOL(cacheid);
90 
91 unsigned int __atags_pointer __initdata;
92 
93 unsigned int system_rev;
94 EXPORT_SYMBOL(system_rev);
95 
96 unsigned int system_serial_low;
97 EXPORT_SYMBOL(system_serial_low);
98 
99 unsigned int system_serial_high;
100 EXPORT_SYMBOL(system_serial_high);
101 
102 unsigned int elf_hwcap __read_mostly;
103 EXPORT_SYMBOL(elf_hwcap);
104 
105 unsigned int elf_hwcap2 __read_mostly;
106 EXPORT_SYMBOL(elf_hwcap2);
107 
108 
109 #ifdef MULTI_CPU
110 struct processor processor __read_mostly;
111 #endif
112 #ifdef MULTI_TLB
113 struct cpu_tlb_fns cpu_tlb __read_mostly;
114 #endif
115 #ifdef MULTI_USER
116 struct cpu_user_fns cpu_user __read_mostly;
117 #endif
118 #ifdef MULTI_CACHE
119 struct cpu_cache_fns cpu_cache __read_mostly;
120 #endif
121 #ifdef CONFIG_OUTER_CACHE
122 struct outer_cache_fns outer_cache __read_mostly;
123 EXPORT_SYMBOL(outer_cache);
124 #endif
125 
126 /*
127  * Cached cpu_architecture() result for use by assembler code.
128  * C code should use the cpu_architecture() function instead of accessing this
129  * variable directly.
130  */
131 int __cpu_architecture __read_mostly = CPU_ARCH_UNKNOWN;
132 
133 struct stack {
134 	u32 irq[3];
135 	u32 abt[3];
136 	u32 und[3];
137 	u32 fiq[3];
138 } ____cacheline_aligned;
139 
140 #ifndef CONFIG_CPU_V7M
141 static struct stack stacks[NR_CPUS];
142 #endif
143 
144 char elf_platform[ELF_PLATFORM_SIZE];
145 EXPORT_SYMBOL(elf_platform);
146 
147 static const char *cpu_name;
148 static const char *machine_name;
149 static char __initdata cmd_line[COMMAND_LINE_SIZE];
150 const struct machine_desc *machine_desc __initdata;
151 
152 static union { char c[4]; unsigned long l; } endian_test __initdata = { { 'l', '?', '?', 'b' } };
153 #define ENDIANNESS ((char)endian_test.l)
154 
155 DEFINE_PER_CPU(struct cpuinfo_arm, cpu_data);
156 
157 /*
158  * Standard memory resources
159  */
160 static struct resource mem_res[] = {
161 	{
162 		.name = "Video RAM",
163 		.start = 0,
164 		.end = 0,
165 		.flags = IORESOURCE_MEM
166 	},
167 	{
168 		.name = "Kernel code",
169 		.start = 0,
170 		.end = 0,
171 		.flags = IORESOURCE_MEM
172 	},
173 	{
174 		.name = "Kernel data",
175 		.start = 0,
176 		.end = 0,
177 		.flags = IORESOURCE_MEM
178 	}
179 };
180 
181 #define video_ram   mem_res[0]
182 #define kernel_code mem_res[1]
183 #define kernel_data mem_res[2]
184 
185 static struct resource io_res[] = {
186 	{
187 		.name = "reserved",
188 		.start = 0x3bc,
189 		.end = 0x3be,
190 		.flags = IORESOURCE_IO | IORESOURCE_BUSY
191 	},
192 	{
193 		.name = "reserved",
194 		.start = 0x378,
195 		.end = 0x37f,
196 		.flags = IORESOURCE_IO | IORESOURCE_BUSY
197 	},
198 	{
199 		.name = "reserved",
200 		.start = 0x278,
201 		.end = 0x27f,
202 		.flags = IORESOURCE_IO | IORESOURCE_BUSY
203 	}
204 };
205 
206 #define lp0 io_res[0]
207 #define lp1 io_res[1]
208 #define lp2 io_res[2]
209 
210 static const char *proc_arch[] = {
211 	"undefined/unknown",
212 	"3",
213 	"4",
214 	"4T",
215 	"5",
216 	"5T",
217 	"5TE",
218 	"5TEJ",
219 	"6TEJ",
220 	"7",
221 	"7M",
222 	"?(12)",
223 	"?(13)",
224 	"?(14)",
225 	"?(15)",
226 	"?(16)",
227 	"?(17)",
228 };
229 
230 #ifdef CONFIG_CPU_V7M
231 static int __get_cpu_architecture(void)
232 {
233 	return CPU_ARCH_ARMv7M;
234 }
235 #else
236 static int __get_cpu_architecture(void)
237 {
238 	int cpu_arch;
239 
240 	if ((read_cpuid_id() & 0x0008f000) == 0) {
241 		cpu_arch = CPU_ARCH_UNKNOWN;
242 	} else if ((read_cpuid_id() & 0x0008f000) == 0x00007000) {
243 		cpu_arch = (read_cpuid_id() & (1 << 23)) ? CPU_ARCH_ARMv4T : CPU_ARCH_ARMv3;
244 	} else if ((read_cpuid_id() & 0x00080000) == 0x00000000) {
245 		cpu_arch = (read_cpuid_id() >> 16) & 7;
246 		if (cpu_arch)
247 			cpu_arch += CPU_ARCH_ARMv3;
248 	} else if ((read_cpuid_id() & 0x000f0000) == 0x000f0000) {
249 		/* Revised CPUID format. Read the Memory Model Feature
250 		 * Register 0 and check for VMSAv7 or PMSAv7 */
251 		unsigned int mmfr0 = read_cpuid_ext(CPUID_EXT_MMFR0);
252 		if ((mmfr0 & 0x0000000f) >= 0x00000003 ||
253 		    (mmfr0 & 0x000000f0) >= 0x00000030)
254 			cpu_arch = CPU_ARCH_ARMv7;
255 		else if ((mmfr0 & 0x0000000f) == 0x00000002 ||
256 			 (mmfr0 & 0x000000f0) == 0x00000020)
257 			cpu_arch = CPU_ARCH_ARMv6;
258 		else
259 			cpu_arch = CPU_ARCH_UNKNOWN;
260 	} else
261 		cpu_arch = CPU_ARCH_UNKNOWN;
262 
263 	return cpu_arch;
264 }
265 #endif
266 
267 int __pure cpu_architecture(void)
268 {
269 	BUG_ON(__cpu_architecture == CPU_ARCH_UNKNOWN);
270 
271 	return __cpu_architecture;
272 }
273 
274 static int cpu_has_aliasing_icache(unsigned int arch)
275 {
276 	int aliasing_icache;
277 	unsigned int id_reg, num_sets, line_size;
278 
279 	/* PIPT caches never alias. */
280 	if (icache_is_pipt())
281 		return 0;
282 
283 	/* arch specifies the register format */
284 	switch (arch) {
285 	case CPU_ARCH_ARMv7:
286 		asm("mcr	p15, 2, %0, c0, c0, 0 @ set CSSELR"
287 		    : /* No output operands */
288 		    : "r" (1));
289 		isb();
290 		asm("mrc	p15, 1, %0, c0, c0, 0 @ read CCSIDR"
291 		    : "=r" (id_reg));
292 		line_size = 4 << ((id_reg & 0x7) + 2);
293 		num_sets = ((id_reg >> 13) & 0x7fff) + 1;
294 		aliasing_icache = (line_size * num_sets) > PAGE_SIZE;
295 		break;
296 	case CPU_ARCH_ARMv6:
297 		aliasing_icache = read_cpuid_cachetype() & (1 << 11);
298 		break;
299 	default:
300 		/* I-cache aliases will be handled by D-cache aliasing code */
301 		aliasing_icache = 0;
302 	}
303 
304 	return aliasing_icache;
305 }
306 
307 static void __init cacheid_init(void)
308 {
309 	unsigned int arch = cpu_architecture();
310 
311 	if (arch == CPU_ARCH_ARMv7M) {
312 		cacheid = 0;
313 	} else if (arch >= CPU_ARCH_ARMv6) {
314 		unsigned int cachetype = read_cpuid_cachetype();
315 		if ((cachetype & (7 << 29)) == 4 << 29) {
316 			/* ARMv7 register format */
317 			arch = CPU_ARCH_ARMv7;
318 			cacheid = CACHEID_VIPT_NONALIASING;
319 			switch (cachetype & (3 << 14)) {
320 			case (1 << 14):
321 				cacheid |= CACHEID_ASID_TAGGED;
322 				break;
323 			case (3 << 14):
324 				cacheid |= CACHEID_PIPT;
325 				break;
326 			}
327 		} else {
328 			arch = CPU_ARCH_ARMv6;
329 			if (cachetype & (1 << 23))
330 				cacheid = CACHEID_VIPT_ALIASING;
331 			else
332 				cacheid = CACHEID_VIPT_NONALIASING;
333 		}
334 		if (cpu_has_aliasing_icache(arch))
335 			cacheid |= CACHEID_VIPT_I_ALIASING;
336 	} else {
337 		cacheid = CACHEID_VIVT;
338 	}
339 
340 	pr_info("CPU: %s data cache, %s instruction cache\n",
341 		cache_is_vivt() ? "VIVT" :
342 		cache_is_vipt_aliasing() ? "VIPT aliasing" :
343 		cache_is_vipt_nonaliasing() ? "PIPT / VIPT nonaliasing" : "unknown",
344 		cache_is_vivt() ? "VIVT" :
345 		icache_is_vivt_asid_tagged() ? "VIVT ASID tagged" :
346 		icache_is_vipt_aliasing() ? "VIPT aliasing" :
347 		icache_is_pipt() ? "PIPT" :
348 		cache_is_vipt_nonaliasing() ? "VIPT nonaliasing" : "unknown");
349 }
350 
351 /*
352  * These functions re-use the assembly code in head.S, which
353  * already provide the required functionality.
354  */
355 extern struct proc_info_list *lookup_processor_type(unsigned int);
356 
357 void __init early_print(const char *str, ...)
358 {
359 	extern void printascii(const char *);
360 	char buf[256];
361 	va_list ap;
362 
363 	va_start(ap, str);
364 	vsnprintf(buf, sizeof(buf), str, ap);
365 	va_end(ap);
366 
367 #ifdef CONFIG_DEBUG_LL
368 	printascii(buf);
369 #endif
370 	printk("%s", buf);
371 }
372 
373 static void __init cpuid_init_hwcaps(void)
374 {
375 	unsigned int divide_instrs, vmsa;
376 
377 	if (cpu_architecture() < CPU_ARCH_ARMv7)
378 		return;
379 
380 	divide_instrs = (read_cpuid_ext(CPUID_EXT_ISAR0) & 0x0f000000) >> 24;
381 
382 	switch (divide_instrs) {
383 	case 2:
384 		elf_hwcap |= HWCAP_IDIVA;
385 	case 1:
386 		elf_hwcap |= HWCAP_IDIVT;
387 	}
388 
389 	/* LPAE implies atomic ldrd/strd instructions */
390 	vmsa = (read_cpuid_ext(CPUID_EXT_MMFR0) & 0xf) >> 0;
391 	if (vmsa >= 5)
392 		elf_hwcap |= HWCAP_LPAE;
393 }
394 
395 static void __init elf_hwcap_fixup(void)
396 {
397 	unsigned id = read_cpuid_id();
398 	unsigned sync_prim;
399 
400 	/*
401 	 * HWCAP_TLS is available only on 1136 r1p0 and later,
402 	 * see also kuser_get_tls_init.
403 	 */
404 	if (read_cpuid_part() == ARM_CPU_PART_ARM1136 &&
405 	    ((id >> 20) & 3) == 0) {
406 		elf_hwcap &= ~HWCAP_TLS;
407 		return;
408 	}
409 
410 	/* Verify if CPUID scheme is implemented */
411 	if ((id & 0x000f0000) != 0x000f0000)
412 		return;
413 
414 	/*
415 	 * If the CPU supports LDREX/STREX and LDREXB/STREXB,
416 	 * avoid advertising SWP; it may not be atomic with
417 	 * multiprocessing cores.
418 	 */
419 	sync_prim = ((read_cpuid_ext(CPUID_EXT_ISAR3) >> 8) & 0xf0) |
420 		    ((read_cpuid_ext(CPUID_EXT_ISAR4) >> 20) & 0x0f);
421 	if (sync_prim >= 0x13)
422 		elf_hwcap &= ~HWCAP_SWP;
423 }
424 
425 /*
426  * cpu_init - initialise one CPU.
427  *
428  * cpu_init sets up the per-CPU stacks.
429  */
430 void notrace cpu_init(void)
431 {
432 #ifndef CONFIG_CPU_V7M
433 	unsigned int cpu = smp_processor_id();
434 	struct stack *stk = &stacks[cpu];
435 
436 	if (cpu >= NR_CPUS) {
437 		pr_crit("CPU%u: bad primary CPU number\n", cpu);
438 		BUG();
439 	}
440 
441 	/*
442 	 * This only works on resume and secondary cores. For booting on the
443 	 * boot cpu, smp_prepare_boot_cpu is called after percpu area setup.
444 	 */
445 	set_my_cpu_offset(per_cpu_offset(cpu));
446 
447 	cpu_proc_init();
448 
449 	/*
450 	 * Define the placement constraint for the inline asm directive below.
451 	 * In Thumb-2, msr with an immediate value is not allowed.
452 	 */
453 #ifdef CONFIG_THUMB2_KERNEL
454 #define PLC	"r"
455 #else
456 #define PLC	"I"
457 #endif
458 
459 	/*
460 	 * setup stacks for re-entrant exception handlers
461 	 */
462 	__asm__ (
463 	"msr	cpsr_c, %1\n\t"
464 	"add	r14, %0, %2\n\t"
465 	"mov	sp, r14\n\t"
466 	"msr	cpsr_c, %3\n\t"
467 	"add	r14, %0, %4\n\t"
468 	"mov	sp, r14\n\t"
469 	"msr	cpsr_c, %5\n\t"
470 	"add	r14, %0, %6\n\t"
471 	"mov	sp, r14\n\t"
472 	"msr	cpsr_c, %7\n\t"
473 	"add	r14, %0, %8\n\t"
474 	"mov	sp, r14\n\t"
475 	"msr	cpsr_c, %9"
476 	    :
477 	    : "r" (stk),
478 	      PLC (PSR_F_BIT | PSR_I_BIT | IRQ_MODE),
479 	      "I" (offsetof(struct stack, irq[0])),
480 	      PLC (PSR_F_BIT | PSR_I_BIT | ABT_MODE),
481 	      "I" (offsetof(struct stack, abt[0])),
482 	      PLC (PSR_F_BIT | PSR_I_BIT | UND_MODE),
483 	      "I" (offsetof(struct stack, und[0])),
484 	      PLC (PSR_F_BIT | PSR_I_BIT | FIQ_MODE),
485 	      "I" (offsetof(struct stack, fiq[0])),
486 	      PLC (PSR_F_BIT | PSR_I_BIT | SVC_MODE)
487 	    : "r14");
488 #endif
489 }
490 
491 u32 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = MPIDR_INVALID };
492 
493 void __init smp_setup_processor_id(void)
494 {
495 	int i;
496 	u32 mpidr = is_smp() ? read_cpuid_mpidr() & MPIDR_HWID_BITMASK : 0;
497 	u32 cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
498 
499 	cpu_logical_map(0) = cpu;
500 	for (i = 1; i < nr_cpu_ids; ++i)
501 		cpu_logical_map(i) = i == cpu ? 0 : i;
502 
503 	/*
504 	 * clear __my_cpu_offset on boot CPU to avoid hang caused by
505 	 * using percpu variable early, for example, lockdep will
506 	 * access percpu variable inside lock_release
507 	 */
508 	set_my_cpu_offset(0);
509 
510 	pr_info("Booting Linux on physical CPU 0x%x\n", mpidr);
511 }
512 
513 struct mpidr_hash mpidr_hash;
514 #ifdef CONFIG_SMP
515 /**
516  * smp_build_mpidr_hash - Pre-compute shifts required at each affinity
517  *			  level in order to build a linear index from an
518  *			  MPIDR value. Resulting algorithm is a collision
519  *			  free hash carried out through shifting and ORing
520  */
521 static void __init smp_build_mpidr_hash(void)
522 {
523 	u32 i, affinity;
524 	u32 fs[3], bits[3], ls, mask = 0;
525 	/*
526 	 * Pre-scan the list of MPIDRS and filter out bits that do
527 	 * not contribute to affinity levels, ie they never toggle.
528 	 */
529 	for_each_possible_cpu(i)
530 		mask |= (cpu_logical_map(i) ^ cpu_logical_map(0));
531 	pr_debug("mask of set bits 0x%x\n", mask);
532 	/*
533 	 * Find and stash the last and first bit set at all affinity levels to
534 	 * check how many bits are required to represent them.
535 	 */
536 	for (i = 0; i < 3; i++) {
537 		affinity = MPIDR_AFFINITY_LEVEL(mask, i);
538 		/*
539 		 * Find the MSB bit and LSB bits position
540 		 * to determine how many bits are required
541 		 * to express the affinity level.
542 		 */
543 		ls = fls(affinity);
544 		fs[i] = affinity ? ffs(affinity) - 1 : 0;
545 		bits[i] = ls - fs[i];
546 	}
547 	/*
548 	 * An index can be created from the MPIDR by isolating the
549 	 * significant bits at each affinity level and by shifting
550 	 * them in order to compress the 24 bits values space to a
551 	 * compressed set of values. This is equivalent to hashing
552 	 * the MPIDR through shifting and ORing. It is a collision free
553 	 * hash though not minimal since some levels might contain a number
554 	 * of CPUs that is not an exact power of 2 and their bit
555 	 * representation might contain holes, eg MPIDR[7:0] = {0x2, 0x80}.
556 	 */
557 	mpidr_hash.shift_aff[0] = fs[0];
558 	mpidr_hash.shift_aff[1] = MPIDR_LEVEL_BITS + fs[1] - bits[0];
559 	mpidr_hash.shift_aff[2] = 2*MPIDR_LEVEL_BITS + fs[2] -
560 						(bits[1] + bits[0]);
561 	mpidr_hash.mask = mask;
562 	mpidr_hash.bits = bits[2] + bits[1] + bits[0];
563 	pr_debug("MPIDR hash: aff0[%u] aff1[%u] aff2[%u] mask[0x%x] bits[%u]\n",
564 				mpidr_hash.shift_aff[0],
565 				mpidr_hash.shift_aff[1],
566 				mpidr_hash.shift_aff[2],
567 				mpidr_hash.mask,
568 				mpidr_hash.bits);
569 	/*
570 	 * 4x is an arbitrary value used to warn on a hash table much bigger
571 	 * than expected on most systems.
572 	 */
573 	if (mpidr_hash_size() > 4 * num_possible_cpus())
574 		pr_warn("Large number of MPIDR hash buckets detected\n");
575 	sync_cache_w(&mpidr_hash);
576 }
577 #endif
578 
579 static void __init setup_processor(void)
580 {
581 	struct proc_info_list *list;
582 
583 	/*
584 	 * locate processor in the list of supported processor
585 	 * types.  The linker builds this table for us from the
586 	 * entries in arch/arm/mm/proc-*.S
587 	 */
588 	list = lookup_processor_type(read_cpuid_id());
589 	if (!list) {
590 		pr_err("CPU configuration botched (ID %08x), unable to continue.\n",
591 		       read_cpuid_id());
592 		while (1);
593 	}
594 
595 	cpu_name = list->cpu_name;
596 	__cpu_architecture = __get_cpu_architecture();
597 
598 #ifdef MULTI_CPU
599 	processor = *list->proc;
600 #endif
601 #ifdef MULTI_TLB
602 	cpu_tlb = *list->tlb;
603 #endif
604 #ifdef MULTI_USER
605 	cpu_user = *list->user;
606 #endif
607 #ifdef MULTI_CACHE
608 	cpu_cache = *list->cache;
609 #endif
610 
611 	pr_info("CPU: %s [%08x] revision %d (ARMv%s), cr=%08lx\n",
612 		cpu_name, read_cpuid_id(), read_cpuid_id() & 15,
613 		proc_arch[cpu_architecture()], get_cr());
614 
615 	snprintf(init_utsname()->machine, __NEW_UTS_LEN + 1, "%s%c",
616 		 list->arch_name, ENDIANNESS);
617 	snprintf(elf_platform, ELF_PLATFORM_SIZE, "%s%c",
618 		 list->elf_name, ENDIANNESS);
619 	elf_hwcap = list->elf_hwcap;
620 
621 	cpuid_init_hwcaps();
622 
623 #ifndef CONFIG_ARM_THUMB
624 	elf_hwcap &= ~(HWCAP_THUMB | HWCAP_IDIVT);
625 #endif
626 #ifdef CONFIG_MMU
627 	init_default_cache_policy(list->__cpu_mm_mmu_flags);
628 #endif
629 	erratum_a15_798181_init();
630 
631 	elf_hwcap_fixup();
632 
633 	cacheid_init();
634 	cpu_init();
635 }
636 
637 void __init dump_machine_table(void)
638 {
639 	const struct machine_desc *p;
640 
641 	early_print("Available machine support:\n\nID (hex)\tNAME\n");
642 	for_each_machine_desc(p)
643 		early_print("%08x\t%s\n", p->nr, p->name);
644 
645 	early_print("\nPlease check your kernel config and/or bootloader.\n");
646 
647 	while (true)
648 		/* can't use cpu_relax() here as it may require MMU setup */;
649 }
650 
651 int __init arm_add_memory(u64 start, u64 size)
652 {
653 	u64 aligned_start;
654 
655 	/*
656 	 * Ensure that start/size are aligned to a page boundary.
657 	 * Size is rounded down, start is rounded up.
658 	 */
659 	aligned_start = PAGE_ALIGN(start);
660 	if (aligned_start > start + size)
661 		size = 0;
662 	else
663 		size -= aligned_start - start;
664 
665 #ifndef CONFIG_ARCH_PHYS_ADDR_T_64BIT
666 	if (aligned_start > ULONG_MAX) {
667 		pr_crit("Ignoring memory at 0x%08llx outside 32-bit physical address space\n",
668 			(long long)start);
669 		return -EINVAL;
670 	}
671 
672 	if (aligned_start + size > ULONG_MAX) {
673 		pr_crit("Truncating memory at 0x%08llx to fit in 32-bit physical address space\n",
674 			(long long)start);
675 		/*
676 		 * To ensure bank->start + bank->size is representable in
677 		 * 32 bits, we use ULONG_MAX as the upper limit rather than 4GB.
678 		 * This means we lose a page after masking.
679 		 */
680 		size = ULONG_MAX - aligned_start;
681 	}
682 #endif
683 
684 	if (aligned_start < PHYS_OFFSET) {
685 		if (aligned_start + size <= PHYS_OFFSET) {
686 			pr_info("Ignoring memory below PHYS_OFFSET: 0x%08llx-0x%08llx\n",
687 				aligned_start, aligned_start + size);
688 			return -EINVAL;
689 		}
690 
691 		pr_info("Ignoring memory below PHYS_OFFSET: 0x%08llx-0x%08llx\n",
692 			aligned_start, (u64)PHYS_OFFSET);
693 
694 		size -= PHYS_OFFSET - aligned_start;
695 		aligned_start = PHYS_OFFSET;
696 	}
697 
698 	start = aligned_start;
699 	size = size & ~(phys_addr_t)(PAGE_SIZE - 1);
700 
701 	/*
702 	 * Check whether this memory region has non-zero size or
703 	 * invalid node number.
704 	 */
705 	if (size == 0)
706 		return -EINVAL;
707 
708 	memblock_add(start, size);
709 	return 0;
710 }
711 
712 /*
713  * Pick out the memory size.  We look for mem=size@start,
714  * where start and size are "size[KkMm]"
715  */
716 
717 static int __init early_mem(char *p)
718 {
719 	static int usermem __initdata = 0;
720 	u64 size;
721 	u64 start;
722 	char *endp;
723 
724 	/*
725 	 * If the user specifies memory size, we
726 	 * blow away any automatically generated
727 	 * size.
728 	 */
729 	if (usermem == 0) {
730 		usermem = 1;
731 		memblock_remove(memblock_start_of_DRAM(),
732 			memblock_end_of_DRAM() - memblock_start_of_DRAM());
733 	}
734 
735 	start = PHYS_OFFSET;
736 	size  = memparse(p, &endp);
737 	if (*endp == '@')
738 		start = memparse(endp + 1, NULL);
739 
740 	arm_add_memory(start, size);
741 
742 	return 0;
743 }
744 early_param("mem", early_mem);
745 
746 static void __init request_standard_resources(const struct machine_desc *mdesc)
747 {
748 	struct memblock_region *region;
749 	struct resource *res;
750 
751 	kernel_code.start   = virt_to_phys(_text);
752 	kernel_code.end     = virt_to_phys(_etext - 1);
753 	kernel_data.start   = virt_to_phys(_sdata);
754 	kernel_data.end     = virt_to_phys(_end - 1);
755 
756 	for_each_memblock(memory, region) {
757 		res = memblock_virt_alloc(sizeof(*res), 0);
758 		res->name  = "System RAM";
759 		res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
760 		res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
761 		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
762 
763 		request_resource(&iomem_resource, res);
764 
765 		if (kernel_code.start >= res->start &&
766 		    kernel_code.end <= res->end)
767 			request_resource(res, &kernel_code);
768 		if (kernel_data.start >= res->start &&
769 		    kernel_data.end <= res->end)
770 			request_resource(res, &kernel_data);
771 	}
772 
773 	if (mdesc->video_start) {
774 		video_ram.start = mdesc->video_start;
775 		video_ram.end   = mdesc->video_end;
776 		request_resource(&iomem_resource, &video_ram);
777 	}
778 
779 	/*
780 	 * Some machines don't have the possibility of ever
781 	 * possessing lp0, lp1 or lp2
782 	 */
783 	if (mdesc->reserve_lp0)
784 		request_resource(&ioport_resource, &lp0);
785 	if (mdesc->reserve_lp1)
786 		request_resource(&ioport_resource, &lp1);
787 	if (mdesc->reserve_lp2)
788 		request_resource(&ioport_resource, &lp2);
789 }
790 
791 #if defined(CONFIG_VGA_CONSOLE) || defined(CONFIG_DUMMY_CONSOLE)
792 struct screen_info screen_info = {
793  .orig_video_lines	= 30,
794  .orig_video_cols	= 80,
795  .orig_video_mode	= 0,
796  .orig_video_ega_bx	= 0,
797  .orig_video_isVGA	= 1,
798  .orig_video_points	= 8
799 };
800 #endif
801 
802 static int __init customize_machine(void)
803 {
804 	/*
805 	 * customizes platform devices, or adds new ones
806 	 * On DT based machines, we fall back to populating the
807 	 * machine from the device tree, if no callback is provided,
808 	 * otherwise we would always need an init_machine callback.
809 	 */
810 	of_iommu_init();
811 	if (machine_desc->init_machine)
812 		machine_desc->init_machine();
813 #ifdef CONFIG_OF
814 	else
815 		of_platform_populate(NULL, of_default_bus_match_table,
816 					NULL, NULL);
817 #endif
818 	return 0;
819 }
820 arch_initcall(customize_machine);
821 
822 static int __init init_machine_late(void)
823 {
824 	if (machine_desc->init_late)
825 		machine_desc->init_late();
826 	return 0;
827 }
828 late_initcall(init_machine_late);
829 
830 #ifdef CONFIG_KEXEC
831 static inline unsigned long long get_total_mem(void)
832 {
833 	unsigned long total;
834 
835 	total = max_low_pfn - min_low_pfn;
836 	return total << PAGE_SHIFT;
837 }
838 
839 /**
840  * reserve_crashkernel() - reserves memory are for crash kernel
841  *
842  * This function reserves memory area given in "crashkernel=" kernel command
843  * line parameter. The memory reserved is used by a dump capture kernel when
844  * primary kernel is crashing.
845  */
846 static void __init reserve_crashkernel(void)
847 {
848 	unsigned long long crash_size, crash_base;
849 	unsigned long long total_mem;
850 	int ret;
851 
852 	total_mem = get_total_mem();
853 	ret = parse_crashkernel(boot_command_line, total_mem,
854 				&crash_size, &crash_base);
855 	if (ret)
856 		return;
857 
858 	ret = memblock_reserve(crash_base, crash_size);
859 	if (ret < 0) {
860 		pr_warn("crashkernel reservation failed - memory is in use (0x%lx)\n",
861 			(unsigned long)crash_base);
862 		return;
863 	}
864 
865 	pr_info("Reserving %ldMB of memory at %ldMB for crashkernel (System RAM: %ldMB)\n",
866 		(unsigned long)(crash_size >> 20),
867 		(unsigned long)(crash_base >> 20),
868 		(unsigned long)(total_mem >> 20));
869 
870 	crashk_res.start = crash_base;
871 	crashk_res.end = crash_base + crash_size - 1;
872 	insert_resource(&iomem_resource, &crashk_res);
873 }
874 #else
875 static inline void reserve_crashkernel(void) {}
876 #endif /* CONFIG_KEXEC */
877 
878 void __init hyp_mode_check(void)
879 {
880 #ifdef CONFIG_ARM_VIRT_EXT
881 	sync_boot_mode();
882 
883 	if (is_hyp_mode_available()) {
884 		pr_info("CPU: All CPU(s) started in HYP mode.\n");
885 		pr_info("CPU: Virtualization extensions available.\n");
886 	} else if (is_hyp_mode_mismatched()) {
887 		pr_warn("CPU: WARNING: CPU(s) started in wrong/inconsistent modes (primary CPU mode 0x%x)\n",
888 			__boot_cpu_mode & MODE_MASK);
889 		pr_warn("CPU: This may indicate a broken bootloader or firmware.\n");
890 	} else
891 		pr_info("CPU: All CPU(s) started in SVC mode.\n");
892 #endif
893 }
894 
895 void __init setup_arch(char **cmdline_p)
896 {
897 	const struct machine_desc *mdesc;
898 
899 	setup_processor();
900 	mdesc = setup_machine_fdt(__atags_pointer);
901 	if (!mdesc)
902 		mdesc = setup_machine_tags(__atags_pointer, __machine_arch_type);
903 	machine_desc = mdesc;
904 	machine_name = mdesc->name;
905 	dump_stack_set_arch_desc("%s", mdesc->name);
906 
907 	if (mdesc->reboot_mode != REBOOT_HARD)
908 		reboot_mode = mdesc->reboot_mode;
909 
910 	init_mm.start_code = (unsigned long) _text;
911 	init_mm.end_code   = (unsigned long) _etext;
912 	init_mm.end_data   = (unsigned long) _edata;
913 	init_mm.brk	   = (unsigned long) _end;
914 
915 	/* populate cmd_line too for later use, preserving boot_command_line */
916 	strlcpy(cmd_line, boot_command_line, COMMAND_LINE_SIZE);
917 	*cmdline_p = cmd_line;
918 
919 	parse_early_param();
920 
921 	early_paging_init(mdesc, lookup_processor_type(read_cpuid_id()));
922 	setup_dma_zone(mdesc);
923 	sanity_check_meminfo();
924 	arm_memblock_init(mdesc);
925 
926 	paging_init(mdesc);
927 	request_standard_resources(mdesc);
928 
929 	if (mdesc->restart)
930 		arm_pm_restart = mdesc->restart;
931 
932 	unflatten_device_tree();
933 
934 	arm_dt_init_cpu_maps();
935 	psci_init();
936 #ifdef CONFIG_SMP
937 	if (is_smp()) {
938 		if (!mdesc->smp_init || !mdesc->smp_init()) {
939 			if (psci_smp_available())
940 				smp_set_ops(&psci_smp_ops);
941 			else if (mdesc->smp)
942 				smp_set_ops(mdesc->smp);
943 		}
944 		smp_init_cpus();
945 		smp_build_mpidr_hash();
946 	}
947 #endif
948 
949 	if (!is_smp())
950 		hyp_mode_check();
951 
952 	reserve_crashkernel();
953 
954 #ifdef CONFIG_MULTI_IRQ_HANDLER
955 	handle_arch_irq = mdesc->handle_irq;
956 #endif
957 
958 #ifdef CONFIG_VT
959 #if defined(CONFIG_VGA_CONSOLE)
960 	conswitchp = &vga_con;
961 #elif defined(CONFIG_DUMMY_CONSOLE)
962 	conswitchp = &dummy_con;
963 #endif
964 #endif
965 
966 	if (mdesc->init_early)
967 		mdesc->init_early();
968 }
969 
970 
971 static int __init topology_init(void)
972 {
973 	int cpu;
974 
975 	for_each_possible_cpu(cpu) {
976 		struct cpuinfo_arm *cpuinfo = &per_cpu(cpu_data, cpu);
977 		cpuinfo->cpu.hotpluggable = 1;
978 		register_cpu(&cpuinfo->cpu, cpu);
979 	}
980 
981 	return 0;
982 }
983 subsys_initcall(topology_init);
984 
985 #ifdef CONFIG_HAVE_PROC_CPU
986 static int __init proc_cpu_init(void)
987 {
988 	struct proc_dir_entry *res;
989 
990 	res = proc_mkdir("cpu", NULL);
991 	if (!res)
992 		return -ENOMEM;
993 	return 0;
994 }
995 fs_initcall(proc_cpu_init);
996 #endif
997 
998 static const char *hwcap_str[] = {
999 	"swp",
1000 	"half",
1001 	"thumb",
1002 	"26bit",
1003 	"fastmult",
1004 	"fpa",
1005 	"vfp",
1006 	"edsp",
1007 	"java",
1008 	"iwmmxt",
1009 	"crunch",
1010 	"thumbee",
1011 	"neon",
1012 	"vfpv3",
1013 	"vfpv3d16",
1014 	"tls",
1015 	"vfpv4",
1016 	"idiva",
1017 	"idivt",
1018 	"vfpd32",
1019 	"lpae",
1020 	"evtstrm",
1021 	NULL
1022 };
1023 
1024 static const char *hwcap2_str[] = {
1025 	"aes",
1026 	"pmull",
1027 	"sha1",
1028 	"sha2",
1029 	"crc32",
1030 	NULL
1031 };
1032 
1033 static int c_show(struct seq_file *m, void *v)
1034 {
1035 	int i, j;
1036 	u32 cpuid;
1037 
1038 	for_each_online_cpu(i) {
1039 		/*
1040 		 * glibc reads /proc/cpuinfo to determine the number of
1041 		 * online processors, looking for lines beginning with
1042 		 * "processor".  Give glibc what it expects.
1043 		 */
1044 		seq_printf(m, "processor\t: %d\n", i);
1045 		cpuid = is_smp() ? per_cpu(cpu_data, i).cpuid : read_cpuid_id();
1046 		seq_printf(m, "model name\t: %s rev %d (%s)\n",
1047 			   cpu_name, cpuid & 15, elf_platform);
1048 
1049 #if defined(CONFIG_SMP)
1050 		seq_printf(m, "BogoMIPS\t: %lu.%02lu\n",
1051 			   per_cpu(cpu_data, i).loops_per_jiffy / (500000UL/HZ),
1052 			   (per_cpu(cpu_data, i).loops_per_jiffy / (5000UL/HZ)) % 100);
1053 #else
1054 		seq_printf(m, "BogoMIPS\t: %lu.%02lu\n",
1055 			   loops_per_jiffy / (500000/HZ),
1056 			   (loops_per_jiffy / (5000/HZ)) % 100);
1057 #endif
1058 		/* dump out the processor features */
1059 		seq_puts(m, "Features\t: ");
1060 
1061 		for (j = 0; hwcap_str[j]; j++)
1062 			if (elf_hwcap & (1 << j))
1063 				seq_printf(m, "%s ", hwcap_str[j]);
1064 
1065 		for (j = 0; hwcap2_str[j]; j++)
1066 			if (elf_hwcap2 & (1 << j))
1067 				seq_printf(m, "%s ", hwcap2_str[j]);
1068 
1069 		seq_printf(m, "\nCPU implementer\t: 0x%02x\n", cpuid >> 24);
1070 		seq_printf(m, "CPU architecture: %s\n",
1071 			   proc_arch[cpu_architecture()]);
1072 
1073 		if ((cpuid & 0x0008f000) == 0x00000000) {
1074 			/* pre-ARM7 */
1075 			seq_printf(m, "CPU part\t: %07x\n", cpuid >> 4);
1076 		} else {
1077 			if ((cpuid & 0x0008f000) == 0x00007000) {
1078 				/* ARM7 */
1079 				seq_printf(m, "CPU variant\t: 0x%02x\n",
1080 					   (cpuid >> 16) & 127);
1081 			} else {
1082 				/* post-ARM7 */
1083 				seq_printf(m, "CPU variant\t: 0x%x\n",
1084 					   (cpuid >> 20) & 15);
1085 			}
1086 			seq_printf(m, "CPU part\t: 0x%03x\n",
1087 				   (cpuid >> 4) & 0xfff);
1088 		}
1089 		seq_printf(m, "CPU revision\t: %d\n\n", cpuid & 15);
1090 	}
1091 
1092 	seq_printf(m, "Hardware\t: %s\n", machine_name);
1093 	seq_printf(m, "Revision\t: %04x\n", system_rev);
1094 	seq_printf(m, "Serial\t\t: %08x%08x\n",
1095 		   system_serial_high, system_serial_low);
1096 
1097 	return 0;
1098 }
1099 
1100 static void *c_start(struct seq_file *m, loff_t *pos)
1101 {
1102 	return *pos < 1 ? (void *)1 : NULL;
1103 }
1104 
1105 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
1106 {
1107 	++*pos;
1108 	return NULL;
1109 }
1110 
1111 static void c_stop(struct seq_file *m, void *v)
1112 {
1113 }
1114 
1115 const struct seq_operations cpuinfo_op = {
1116 	.start	= c_start,
1117 	.next	= c_next,
1118 	.stop	= c_stop,
1119 	.show	= c_show
1120 };
1121