xref: /openbmc/linux/arch/arm/kernel/setup.c (revision 609e478b)
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_platform.h>
22 #include <linux/init.h>
23 #include <linux/kexec.h>
24 #include <linux/of_fdt.h>
25 #include <linux/cpu.h>
26 #include <linux/interrupt.h>
27 #include <linux/smp.h>
28 #include <linux/proc_fs.h>
29 #include <linux/memblock.h>
30 #include <linux/bug.h>
31 #include <linux/compiler.h>
32 #include <linux/sort.h>
33 
34 #include <asm/unified.h>
35 #include <asm/cp15.h>
36 #include <asm/cpu.h>
37 #include <asm/cputype.h>
38 #include <asm/elf.h>
39 #include <asm/procinfo.h>
40 #include <asm/psci.h>
41 #include <asm/sections.h>
42 #include <asm/setup.h>
43 #include <asm/smp_plat.h>
44 #include <asm/mach-types.h>
45 #include <asm/cacheflush.h>
46 #include <asm/cachetype.h>
47 #include <asm/tlbflush.h>
48 
49 #include <asm/prom.h>
50 #include <asm/mach/arch.h>
51 #include <asm/mach/irq.h>
52 #include <asm/mach/time.h>
53 #include <asm/system_info.h>
54 #include <asm/system_misc.h>
55 #include <asm/traps.h>
56 #include <asm/unwind.h>
57 #include <asm/memblock.h>
58 #include <asm/virt.h>
59 
60 #include "atags.h"
61 
62 
63 #if defined(CONFIG_FPE_NWFPE) || defined(CONFIG_FPE_FASTFPE)
64 char fpe_type[8];
65 
66 static int __init fpe_setup(char *line)
67 {
68 	memcpy(fpe_type, line, 8);
69 	return 1;
70 }
71 
72 __setup("fpe=", fpe_setup);
73 #endif
74 
75 extern void init_default_cache_policy(unsigned long);
76 extern void paging_init(const struct machine_desc *desc);
77 extern void early_paging_init(const struct machine_desc *,
78 			      struct proc_info_list *);
79 extern void sanity_check_meminfo(void);
80 extern enum reboot_mode reboot_mode;
81 extern void setup_dma_zone(const struct machine_desc *desc);
82 
83 unsigned int processor_id;
84 EXPORT_SYMBOL(processor_id);
85 unsigned int __machine_arch_type __read_mostly;
86 EXPORT_SYMBOL(__machine_arch_type);
87 unsigned int cacheid __read_mostly;
88 EXPORT_SYMBOL(cacheid);
89 
90 unsigned int __atags_pointer __initdata;
91 
92 unsigned int system_rev;
93 EXPORT_SYMBOL(system_rev);
94 
95 unsigned int system_serial_low;
96 EXPORT_SYMBOL(system_serial_low);
97 
98 unsigned int system_serial_high;
99 EXPORT_SYMBOL(system_serial_high);
100 
101 unsigned int elf_hwcap __read_mostly;
102 EXPORT_SYMBOL(elf_hwcap);
103 
104 unsigned int elf_hwcap2 __read_mostly;
105 EXPORT_SYMBOL(elf_hwcap2);
106 
107 
108 #ifdef MULTI_CPU
109 struct processor processor __read_mostly;
110 #endif
111 #ifdef MULTI_TLB
112 struct cpu_tlb_fns cpu_tlb __read_mostly;
113 #endif
114 #ifdef MULTI_USER
115 struct cpu_user_fns cpu_user __read_mostly;
116 #endif
117 #ifdef MULTI_CACHE
118 struct cpu_cache_fns cpu_cache __read_mostly;
119 #endif
120 #ifdef CONFIG_OUTER_CACHE
121 struct outer_cache_fns outer_cache __read_mostly;
122 EXPORT_SYMBOL(outer_cache);
123 #endif
124 
125 /*
126  * Cached cpu_architecture() result for use by assembler code.
127  * C code should use the cpu_architecture() function instead of accessing this
128  * variable directly.
129  */
130 int __cpu_architecture __read_mostly = CPU_ARCH_UNKNOWN;
131 
132 struct stack {
133 	u32 irq[3];
134 	u32 abt[3];
135 	u32 und[3];
136 	u32 fiq[3];
137 } ____cacheline_aligned;
138 
139 #ifndef CONFIG_CPU_V7M
140 static struct stack stacks[NR_CPUS];
141 #endif
142 
143 char elf_platform[ELF_PLATFORM_SIZE];
144 EXPORT_SYMBOL(elf_platform);
145 
146 static const char *cpu_name;
147 static const char *machine_name;
148 static char __initdata cmd_line[COMMAND_LINE_SIZE];
149 const struct machine_desc *machine_desc __initdata;
150 
151 static union { char c[4]; unsigned long l; } endian_test __initdata = { { 'l', '?', '?', 'b' } };
152 #define ENDIANNESS ((char)endian_test.l)
153 
154 DEFINE_PER_CPU(struct cpuinfo_arm, cpu_data);
155 
156 /*
157  * Standard memory resources
158  */
159 static struct resource mem_res[] = {
160 	{
161 		.name = "Video RAM",
162 		.start = 0,
163 		.end = 0,
164 		.flags = IORESOURCE_MEM
165 	},
166 	{
167 		.name = "Kernel code",
168 		.start = 0,
169 		.end = 0,
170 		.flags = IORESOURCE_MEM
171 	},
172 	{
173 		.name = "Kernel data",
174 		.start = 0,
175 		.end = 0,
176 		.flags = IORESOURCE_MEM
177 	}
178 };
179 
180 #define video_ram   mem_res[0]
181 #define kernel_code mem_res[1]
182 #define kernel_data mem_res[2]
183 
184 static struct resource io_res[] = {
185 	{
186 		.name = "reserved",
187 		.start = 0x3bc,
188 		.end = 0x3be,
189 		.flags = IORESOURCE_IO | IORESOURCE_BUSY
190 	},
191 	{
192 		.name = "reserved",
193 		.start = 0x378,
194 		.end = 0x37f,
195 		.flags = IORESOURCE_IO | IORESOURCE_BUSY
196 	},
197 	{
198 		.name = "reserved",
199 		.start = 0x278,
200 		.end = 0x27f,
201 		.flags = IORESOURCE_IO | IORESOURCE_BUSY
202 	}
203 };
204 
205 #define lp0 io_res[0]
206 #define lp1 io_res[1]
207 #define lp2 io_res[2]
208 
209 static const char *proc_arch[] = {
210 	"undefined/unknown",
211 	"3",
212 	"4",
213 	"4T",
214 	"5",
215 	"5T",
216 	"5TE",
217 	"5TEJ",
218 	"6TEJ",
219 	"7",
220 	"7M",
221 	"?(12)",
222 	"?(13)",
223 	"?(14)",
224 	"?(15)",
225 	"?(16)",
226 	"?(17)",
227 };
228 
229 #ifdef CONFIG_CPU_V7M
230 static int __get_cpu_architecture(void)
231 {
232 	return CPU_ARCH_ARMv7M;
233 }
234 #else
235 static int __get_cpu_architecture(void)
236 {
237 	int cpu_arch;
238 
239 	if ((read_cpuid_id() & 0x0008f000) == 0) {
240 		cpu_arch = CPU_ARCH_UNKNOWN;
241 	} else if ((read_cpuid_id() & 0x0008f000) == 0x00007000) {
242 		cpu_arch = (read_cpuid_id() & (1 << 23)) ? CPU_ARCH_ARMv4T : CPU_ARCH_ARMv3;
243 	} else if ((read_cpuid_id() & 0x00080000) == 0x00000000) {
244 		cpu_arch = (read_cpuid_id() >> 16) & 7;
245 		if (cpu_arch)
246 			cpu_arch += CPU_ARCH_ARMv3;
247 	} else if ((read_cpuid_id() & 0x000f0000) == 0x000f0000) {
248 		unsigned int mmfr0;
249 
250 		/* Revised CPUID format. Read the Memory Model Feature
251 		 * Register 0 and check for VMSAv7 or PMSAv7 */
252 		asm("mrc	p15, 0, %0, c0, c1, 4"
253 		    : "=r" (mmfr0));
254 		if ((mmfr0 & 0x0000000f) >= 0x00000003 ||
255 		    (mmfr0 & 0x000000f0) >= 0x00000030)
256 			cpu_arch = CPU_ARCH_ARMv7;
257 		else if ((mmfr0 & 0x0000000f) == 0x00000002 ||
258 			 (mmfr0 & 0x000000f0) == 0x00000020)
259 			cpu_arch = CPU_ARCH_ARMv6;
260 		else
261 			cpu_arch = CPU_ARCH_UNKNOWN;
262 	} else
263 		cpu_arch = CPU_ARCH_UNKNOWN;
264 
265 	return cpu_arch;
266 }
267 #endif
268 
269 int __pure cpu_architecture(void)
270 {
271 	BUG_ON(__cpu_architecture == CPU_ARCH_UNKNOWN);
272 
273 	return __cpu_architecture;
274 }
275 
276 static int cpu_has_aliasing_icache(unsigned int arch)
277 {
278 	int aliasing_icache;
279 	unsigned int id_reg, num_sets, line_size;
280 
281 	/* PIPT caches never alias. */
282 	if (icache_is_pipt())
283 		return 0;
284 
285 	/* arch specifies the register format */
286 	switch (arch) {
287 	case CPU_ARCH_ARMv7:
288 		asm("mcr	p15, 2, %0, c0, c0, 0 @ set CSSELR"
289 		    : /* No output operands */
290 		    : "r" (1));
291 		isb();
292 		asm("mrc	p15, 1, %0, c0, c0, 0 @ read CCSIDR"
293 		    : "=r" (id_reg));
294 		line_size = 4 << ((id_reg & 0x7) + 2);
295 		num_sets = ((id_reg >> 13) & 0x7fff) + 1;
296 		aliasing_icache = (line_size * num_sets) > PAGE_SIZE;
297 		break;
298 	case CPU_ARCH_ARMv6:
299 		aliasing_icache = read_cpuid_cachetype() & (1 << 11);
300 		break;
301 	default:
302 		/* I-cache aliases will be handled by D-cache aliasing code */
303 		aliasing_icache = 0;
304 	}
305 
306 	return aliasing_icache;
307 }
308 
309 static void __init cacheid_init(void)
310 {
311 	unsigned int arch = cpu_architecture();
312 
313 	if (arch == CPU_ARCH_ARMv7M) {
314 		cacheid = 0;
315 	} else if (arch >= CPU_ARCH_ARMv6) {
316 		unsigned int cachetype = read_cpuid_cachetype();
317 		if ((cachetype & (7 << 29)) == 4 << 29) {
318 			/* ARMv7 register format */
319 			arch = CPU_ARCH_ARMv7;
320 			cacheid = CACHEID_VIPT_NONALIASING;
321 			switch (cachetype & (3 << 14)) {
322 			case (1 << 14):
323 				cacheid |= CACHEID_ASID_TAGGED;
324 				break;
325 			case (3 << 14):
326 				cacheid |= CACHEID_PIPT;
327 				break;
328 			}
329 		} else {
330 			arch = CPU_ARCH_ARMv6;
331 			if (cachetype & (1 << 23))
332 				cacheid = CACHEID_VIPT_ALIASING;
333 			else
334 				cacheid = CACHEID_VIPT_NONALIASING;
335 		}
336 		if (cpu_has_aliasing_icache(arch))
337 			cacheid |= CACHEID_VIPT_I_ALIASING;
338 	} else {
339 		cacheid = CACHEID_VIVT;
340 	}
341 
342 	pr_info("CPU: %s data cache, %s instruction cache\n",
343 		cache_is_vivt() ? "VIVT" :
344 		cache_is_vipt_aliasing() ? "VIPT aliasing" :
345 		cache_is_vipt_nonaliasing() ? "PIPT / VIPT nonaliasing" : "unknown",
346 		cache_is_vivt() ? "VIVT" :
347 		icache_is_vivt_asid_tagged() ? "VIVT ASID tagged" :
348 		icache_is_vipt_aliasing() ? "VIPT aliasing" :
349 		icache_is_pipt() ? "PIPT" :
350 		cache_is_vipt_nonaliasing() ? "VIPT nonaliasing" : "unknown");
351 }
352 
353 /*
354  * These functions re-use the assembly code in head.S, which
355  * already provide the required functionality.
356  */
357 extern struct proc_info_list *lookup_processor_type(unsigned int);
358 
359 void __init early_print(const char *str, ...)
360 {
361 	extern void printascii(const char *);
362 	char buf[256];
363 	va_list ap;
364 
365 	va_start(ap, str);
366 	vsnprintf(buf, sizeof(buf), str, ap);
367 	va_end(ap);
368 
369 #ifdef CONFIG_DEBUG_LL
370 	printascii(buf);
371 #endif
372 	printk("%s", buf);
373 }
374 
375 static void __init cpuid_init_hwcaps(void)
376 {
377 	unsigned int divide_instrs, vmsa;
378 
379 	if (cpu_architecture() < CPU_ARCH_ARMv7)
380 		return;
381 
382 	divide_instrs = (read_cpuid_ext(CPUID_EXT_ISAR0) & 0x0f000000) >> 24;
383 
384 	switch (divide_instrs) {
385 	case 2:
386 		elf_hwcap |= HWCAP_IDIVA;
387 	case 1:
388 		elf_hwcap |= HWCAP_IDIVT;
389 	}
390 
391 	/* LPAE implies atomic ldrd/strd instructions */
392 	vmsa = (read_cpuid_ext(CPUID_EXT_MMFR0) & 0xf) >> 0;
393 	if (vmsa >= 5)
394 		elf_hwcap |= HWCAP_LPAE;
395 }
396 
397 static void __init elf_hwcap_fixup(void)
398 {
399 	unsigned id = read_cpuid_id();
400 	unsigned sync_prim;
401 
402 	/*
403 	 * HWCAP_TLS is available only on 1136 r1p0 and later,
404 	 * see also kuser_get_tls_init.
405 	 */
406 	if (read_cpuid_part() == ARM_CPU_PART_ARM1136 &&
407 	    ((id >> 20) & 3) == 0) {
408 		elf_hwcap &= ~HWCAP_TLS;
409 		return;
410 	}
411 
412 	/* Verify if CPUID scheme is implemented */
413 	if ((id & 0x000f0000) != 0x000f0000)
414 		return;
415 
416 	/*
417 	 * If the CPU supports LDREX/STREX and LDREXB/STREXB,
418 	 * avoid advertising SWP; it may not be atomic with
419 	 * multiprocessing cores.
420 	 */
421 	sync_prim = ((read_cpuid_ext(CPUID_EXT_ISAR3) >> 8) & 0xf0) |
422 		    ((read_cpuid_ext(CPUID_EXT_ISAR4) >> 20) & 0x0f);
423 	if (sync_prim >= 0x13)
424 		elf_hwcap &= ~HWCAP_SWP;
425 }
426 
427 /*
428  * cpu_init - initialise one CPU.
429  *
430  * cpu_init sets up the per-CPU stacks.
431  */
432 void notrace cpu_init(void)
433 {
434 #ifndef CONFIG_CPU_V7M
435 	unsigned int cpu = smp_processor_id();
436 	struct stack *stk = &stacks[cpu];
437 
438 	if (cpu >= NR_CPUS) {
439 		pr_crit("CPU%u: bad primary CPU number\n", cpu);
440 		BUG();
441 	}
442 
443 	/*
444 	 * This only works on resume and secondary cores. For booting on the
445 	 * boot cpu, smp_prepare_boot_cpu is called after percpu area setup.
446 	 */
447 	set_my_cpu_offset(per_cpu_offset(cpu));
448 
449 	cpu_proc_init();
450 
451 	/*
452 	 * Define the placement constraint for the inline asm directive below.
453 	 * In Thumb-2, msr with an immediate value is not allowed.
454 	 */
455 #ifdef CONFIG_THUMB2_KERNEL
456 #define PLC	"r"
457 #else
458 #define PLC	"I"
459 #endif
460 
461 	/*
462 	 * setup stacks for re-entrant exception handlers
463 	 */
464 	__asm__ (
465 	"msr	cpsr_c, %1\n\t"
466 	"add	r14, %0, %2\n\t"
467 	"mov	sp, r14\n\t"
468 	"msr	cpsr_c, %3\n\t"
469 	"add	r14, %0, %4\n\t"
470 	"mov	sp, r14\n\t"
471 	"msr	cpsr_c, %5\n\t"
472 	"add	r14, %0, %6\n\t"
473 	"mov	sp, r14\n\t"
474 	"msr	cpsr_c, %7\n\t"
475 	"add	r14, %0, %8\n\t"
476 	"mov	sp, r14\n\t"
477 	"msr	cpsr_c, %9"
478 	    :
479 	    : "r" (stk),
480 	      PLC (PSR_F_BIT | PSR_I_BIT | IRQ_MODE),
481 	      "I" (offsetof(struct stack, irq[0])),
482 	      PLC (PSR_F_BIT | PSR_I_BIT | ABT_MODE),
483 	      "I" (offsetof(struct stack, abt[0])),
484 	      PLC (PSR_F_BIT | PSR_I_BIT | UND_MODE),
485 	      "I" (offsetof(struct stack, und[0])),
486 	      PLC (PSR_F_BIT | PSR_I_BIT | FIQ_MODE),
487 	      "I" (offsetof(struct stack, fiq[0])),
488 	      PLC (PSR_F_BIT | PSR_I_BIT | SVC_MODE)
489 	    : "r14");
490 #endif
491 }
492 
493 u32 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = MPIDR_INVALID };
494 
495 void __init smp_setup_processor_id(void)
496 {
497 	int i;
498 	u32 mpidr = is_smp() ? read_cpuid_mpidr() & MPIDR_HWID_BITMASK : 0;
499 	u32 cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
500 
501 	cpu_logical_map(0) = cpu;
502 	for (i = 1; i < nr_cpu_ids; ++i)
503 		cpu_logical_map(i) = i == cpu ? 0 : i;
504 
505 	/*
506 	 * clear __my_cpu_offset on boot CPU to avoid hang caused by
507 	 * using percpu variable early, for example, lockdep will
508 	 * access percpu variable inside lock_release
509 	 */
510 	set_my_cpu_offset(0);
511 
512 	pr_info("Booting Linux on physical CPU 0x%x\n", mpidr);
513 }
514 
515 struct mpidr_hash mpidr_hash;
516 #ifdef CONFIG_SMP
517 /**
518  * smp_build_mpidr_hash - Pre-compute shifts required at each affinity
519  *			  level in order to build a linear index from an
520  *			  MPIDR value. Resulting algorithm is a collision
521  *			  free hash carried out through shifting and ORing
522  */
523 static void __init smp_build_mpidr_hash(void)
524 {
525 	u32 i, affinity;
526 	u32 fs[3], bits[3], ls, mask = 0;
527 	/*
528 	 * Pre-scan the list of MPIDRS and filter out bits that do
529 	 * not contribute to affinity levels, ie they never toggle.
530 	 */
531 	for_each_possible_cpu(i)
532 		mask |= (cpu_logical_map(i) ^ cpu_logical_map(0));
533 	pr_debug("mask of set bits 0x%x\n", mask);
534 	/*
535 	 * Find and stash the last and first bit set at all affinity levels to
536 	 * check how many bits are required to represent them.
537 	 */
538 	for (i = 0; i < 3; i++) {
539 		affinity = MPIDR_AFFINITY_LEVEL(mask, i);
540 		/*
541 		 * Find the MSB bit and LSB bits position
542 		 * to determine how many bits are required
543 		 * to express the affinity level.
544 		 */
545 		ls = fls(affinity);
546 		fs[i] = affinity ? ffs(affinity) - 1 : 0;
547 		bits[i] = ls - fs[i];
548 	}
549 	/*
550 	 * An index can be created from the MPIDR by isolating the
551 	 * significant bits at each affinity level and by shifting
552 	 * them in order to compress the 24 bits values space to a
553 	 * compressed set of values. This is equivalent to hashing
554 	 * the MPIDR through shifting and ORing. It is a collision free
555 	 * hash though not minimal since some levels might contain a number
556 	 * of CPUs that is not an exact power of 2 and their bit
557 	 * representation might contain holes, eg MPIDR[7:0] = {0x2, 0x80}.
558 	 */
559 	mpidr_hash.shift_aff[0] = fs[0];
560 	mpidr_hash.shift_aff[1] = MPIDR_LEVEL_BITS + fs[1] - bits[0];
561 	mpidr_hash.shift_aff[2] = 2*MPIDR_LEVEL_BITS + fs[2] -
562 						(bits[1] + bits[0]);
563 	mpidr_hash.mask = mask;
564 	mpidr_hash.bits = bits[2] + bits[1] + bits[0];
565 	pr_debug("MPIDR hash: aff0[%u] aff1[%u] aff2[%u] mask[0x%x] bits[%u]\n",
566 				mpidr_hash.shift_aff[0],
567 				mpidr_hash.shift_aff[1],
568 				mpidr_hash.shift_aff[2],
569 				mpidr_hash.mask,
570 				mpidr_hash.bits);
571 	/*
572 	 * 4x is an arbitrary value used to warn on a hash table much bigger
573 	 * than expected on most systems.
574 	 */
575 	if (mpidr_hash_size() > 4 * num_possible_cpus())
576 		pr_warn("Large number of MPIDR hash buckets detected\n");
577 	sync_cache_w(&mpidr_hash);
578 }
579 #endif
580 
581 static void __init setup_processor(void)
582 {
583 	struct proc_info_list *list;
584 
585 	/*
586 	 * locate processor in the list of supported processor
587 	 * types.  The linker builds this table for us from the
588 	 * entries in arch/arm/mm/proc-*.S
589 	 */
590 	list = lookup_processor_type(read_cpuid_id());
591 	if (!list) {
592 		pr_err("CPU configuration botched (ID %08x), unable to continue.\n",
593 		       read_cpuid_id());
594 		while (1);
595 	}
596 
597 	cpu_name = list->cpu_name;
598 	__cpu_architecture = __get_cpu_architecture();
599 
600 #ifdef MULTI_CPU
601 	processor = *list->proc;
602 #endif
603 #ifdef MULTI_TLB
604 	cpu_tlb = *list->tlb;
605 #endif
606 #ifdef MULTI_USER
607 	cpu_user = *list->user;
608 #endif
609 #ifdef MULTI_CACHE
610 	cpu_cache = *list->cache;
611 #endif
612 
613 	pr_info("CPU: %s [%08x] revision %d (ARMv%s), cr=%08lx\n",
614 		cpu_name, read_cpuid_id(), read_cpuid_id() & 15,
615 		proc_arch[cpu_architecture()], get_cr());
616 
617 	snprintf(init_utsname()->machine, __NEW_UTS_LEN + 1, "%s%c",
618 		 list->arch_name, ENDIANNESS);
619 	snprintf(elf_platform, ELF_PLATFORM_SIZE, "%s%c",
620 		 list->elf_name, ENDIANNESS);
621 	elf_hwcap = list->elf_hwcap;
622 
623 	cpuid_init_hwcaps();
624 
625 #ifndef CONFIG_ARM_THUMB
626 	elf_hwcap &= ~(HWCAP_THUMB | HWCAP_IDIVT);
627 #endif
628 #ifdef CONFIG_MMU
629 	init_default_cache_policy(list->__cpu_mm_mmu_flags);
630 #endif
631 	erratum_a15_798181_init();
632 
633 	elf_hwcap_fixup();
634 
635 	cacheid_init();
636 	cpu_init();
637 }
638 
639 void __init dump_machine_table(void)
640 {
641 	const struct machine_desc *p;
642 
643 	early_print("Available machine support:\n\nID (hex)\tNAME\n");
644 	for_each_machine_desc(p)
645 		early_print("%08x\t%s\n", p->nr, p->name);
646 
647 	early_print("\nPlease check your kernel config and/or bootloader.\n");
648 
649 	while (true)
650 		/* can't use cpu_relax() here as it may require MMU setup */;
651 }
652 
653 int __init arm_add_memory(u64 start, u64 size)
654 {
655 	u64 aligned_start;
656 
657 	/*
658 	 * Ensure that start/size are aligned to a page boundary.
659 	 * Size is appropriately rounded down, start is rounded up.
660 	 */
661 	size -= start & ~PAGE_MASK;
662 	aligned_start = PAGE_ALIGN(start);
663 
664 #ifndef CONFIG_ARCH_PHYS_ADDR_T_64BIT
665 	if (aligned_start > ULONG_MAX) {
666 		pr_crit("Ignoring memory at 0x%08llx outside 32-bit physical address space\n",
667 			(long long)start);
668 		return -EINVAL;
669 	}
670 
671 	if (aligned_start + size > ULONG_MAX) {
672 		pr_crit("Truncating memory at 0x%08llx to fit in 32-bit physical address space\n",
673 			(long long)start);
674 		/*
675 		 * To ensure bank->start + bank->size is representable in
676 		 * 32 bits, we use ULONG_MAX as the upper limit rather than 4GB.
677 		 * This means we lose a page after masking.
678 		 */
679 		size = ULONG_MAX - aligned_start;
680 	}
681 #endif
682 
683 	if (aligned_start < PHYS_OFFSET) {
684 		if (aligned_start + size <= PHYS_OFFSET) {
685 			pr_info("Ignoring memory below PHYS_OFFSET: 0x%08llx-0x%08llx\n",
686 				aligned_start, aligned_start + size);
687 			return -EINVAL;
688 		}
689 
690 		pr_info("Ignoring memory below PHYS_OFFSET: 0x%08llx-0x%08llx\n",
691 			aligned_start, (u64)PHYS_OFFSET);
692 
693 		size -= PHYS_OFFSET - aligned_start;
694 		aligned_start = PHYS_OFFSET;
695 	}
696 
697 	start = aligned_start;
698 	size = size & ~(phys_addr_t)(PAGE_SIZE - 1);
699 
700 	/*
701 	 * Check whether this memory region has non-zero size or
702 	 * invalid node number.
703 	 */
704 	if (size == 0)
705 		return -EINVAL;
706 
707 	memblock_add(start, size);
708 	return 0;
709 }
710 
711 /*
712  * Pick out the memory size.  We look for mem=size@start,
713  * where start and size are "size[KkMm]"
714  */
715 
716 static int __init early_mem(char *p)
717 {
718 	static int usermem __initdata = 0;
719 	u64 size;
720 	u64 start;
721 	char *endp;
722 
723 	/*
724 	 * If the user specifies memory size, we
725 	 * blow away any automatically generated
726 	 * size.
727 	 */
728 	if (usermem == 0) {
729 		usermem = 1;
730 		memblock_remove(memblock_start_of_DRAM(),
731 			memblock_end_of_DRAM() - memblock_start_of_DRAM());
732 	}
733 
734 	start = PHYS_OFFSET;
735 	size  = memparse(p, &endp);
736 	if (*endp == '@')
737 		start = memparse(endp + 1, NULL);
738 
739 	arm_add_memory(start, size);
740 
741 	return 0;
742 }
743 early_param("mem", early_mem);
744 
745 static void __init request_standard_resources(const struct machine_desc *mdesc)
746 {
747 	struct memblock_region *region;
748 	struct resource *res;
749 
750 	kernel_code.start   = virt_to_phys(_text);
751 	kernel_code.end     = virt_to_phys(_etext - 1);
752 	kernel_data.start   = virt_to_phys(_sdata);
753 	kernel_data.end     = virt_to_phys(_end - 1);
754 
755 	for_each_memblock(memory, region) {
756 		res = memblock_virt_alloc(sizeof(*res), 0);
757 		res->name  = "System RAM";
758 		res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
759 		res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
760 		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
761 
762 		request_resource(&iomem_resource, res);
763 
764 		if (kernel_code.start >= res->start &&
765 		    kernel_code.end <= res->end)
766 			request_resource(res, &kernel_code);
767 		if (kernel_data.start >= res->start &&
768 		    kernel_data.end <= res->end)
769 			request_resource(res, &kernel_data);
770 	}
771 
772 	if (mdesc->video_start) {
773 		video_ram.start = mdesc->video_start;
774 		video_ram.end   = mdesc->video_end;
775 		request_resource(&iomem_resource, &video_ram);
776 	}
777 
778 	/*
779 	 * Some machines don't have the possibility of ever
780 	 * possessing lp0, lp1 or lp2
781 	 */
782 	if (mdesc->reserve_lp0)
783 		request_resource(&ioport_resource, &lp0);
784 	if (mdesc->reserve_lp1)
785 		request_resource(&ioport_resource, &lp1);
786 	if (mdesc->reserve_lp2)
787 		request_resource(&ioport_resource, &lp2);
788 }
789 
790 #if defined(CONFIG_VGA_CONSOLE) || defined(CONFIG_DUMMY_CONSOLE)
791 struct screen_info screen_info = {
792  .orig_video_lines	= 30,
793  .orig_video_cols	= 80,
794  .orig_video_mode	= 0,
795  .orig_video_ega_bx	= 0,
796  .orig_video_isVGA	= 1,
797  .orig_video_points	= 8
798 };
799 #endif
800 
801 static int __init customize_machine(void)
802 {
803 	/*
804 	 * customizes platform devices, or adds new ones
805 	 * On DT based machines, we fall back to populating the
806 	 * machine from the device tree, if no callback is provided,
807 	 * otherwise we would always need an init_machine callback.
808 	 */
809 	if (machine_desc->init_machine)
810 		machine_desc->init_machine();
811 #ifdef CONFIG_OF
812 	else
813 		of_platform_populate(NULL, of_default_bus_match_table,
814 					NULL, NULL);
815 #endif
816 	return 0;
817 }
818 arch_initcall(customize_machine);
819 
820 static int __init init_machine_late(void)
821 {
822 	if (machine_desc->init_late)
823 		machine_desc->init_late();
824 	return 0;
825 }
826 late_initcall(init_machine_late);
827 
828 #ifdef CONFIG_KEXEC
829 static inline unsigned long long get_total_mem(void)
830 {
831 	unsigned long total;
832 
833 	total = max_low_pfn - min_low_pfn;
834 	return total << PAGE_SHIFT;
835 }
836 
837 /**
838  * reserve_crashkernel() - reserves memory are for crash kernel
839  *
840  * This function reserves memory area given in "crashkernel=" kernel command
841  * line parameter. The memory reserved is used by a dump capture kernel when
842  * primary kernel is crashing.
843  */
844 static void __init reserve_crashkernel(void)
845 {
846 	unsigned long long crash_size, crash_base;
847 	unsigned long long total_mem;
848 	int ret;
849 
850 	total_mem = get_total_mem();
851 	ret = parse_crashkernel(boot_command_line, total_mem,
852 				&crash_size, &crash_base);
853 	if (ret)
854 		return;
855 
856 	ret = memblock_reserve(crash_base, crash_size);
857 	if (ret < 0) {
858 		pr_warn("crashkernel reservation failed - memory is in use (0x%lx)\n",
859 			(unsigned long)crash_base);
860 		return;
861 	}
862 
863 	pr_info("Reserving %ldMB of memory at %ldMB for crashkernel (System RAM: %ldMB)\n",
864 		(unsigned long)(crash_size >> 20),
865 		(unsigned long)(crash_base >> 20),
866 		(unsigned long)(total_mem >> 20));
867 
868 	crashk_res.start = crash_base;
869 	crashk_res.end = crash_base + crash_size - 1;
870 	insert_resource(&iomem_resource, &crashk_res);
871 }
872 #else
873 static inline void reserve_crashkernel(void) {}
874 #endif /* CONFIG_KEXEC */
875 
876 void __init hyp_mode_check(void)
877 {
878 #ifdef CONFIG_ARM_VIRT_EXT
879 	sync_boot_mode();
880 
881 	if (is_hyp_mode_available()) {
882 		pr_info("CPU: All CPU(s) started in HYP mode.\n");
883 		pr_info("CPU: Virtualization extensions available.\n");
884 	} else if (is_hyp_mode_mismatched()) {
885 		pr_warn("CPU: WARNING: CPU(s) started in wrong/inconsistent modes (primary CPU mode 0x%x)\n",
886 			__boot_cpu_mode & MODE_MASK);
887 		pr_warn("CPU: This may indicate a broken bootloader or firmware.\n");
888 	} else
889 		pr_info("CPU: All CPU(s) started in SVC mode.\n");
890 #endif
891 }
892 
893 void __init setup_arch(char **cmdline_p)
894 {
895 	const struct machine_desc *mdesc;
896 
897 	setup_processor();
898 	mdesc = setup_machine_fdt(__atags_pointer);
899 	if (!mdesc)
900 		mdesc = setup_machine_tags(__atags_pointer, __machine_arch_type);
901 	machine_desc = mdesc;
902 	machine_name = mdesc->name;
903 
904 	if (mdesc->reboot_mode != REBOOT_HARD)
905 		reboot_mode = mdesc->reboot_mode;
906 
907 	init_mm.start_code = (unsigned long) _text;
908 	init_mm.end_code   = (unsigned long) _etext;
909 	init_mm.end_data   = (unsigned long) _edata;
910 	init_mm.brk	   = (unsigned long) _end;
911 
912 	/* populate cmd_line too for later use, preserving boot_command_line */
913 	strlcpy(cmd_line, boot_command_line, COMMAND_LINE_SIZE);
914 	*cmdline_p = cmd_line;
915 
916 	parse_early_param();
917 
918 	early_paging_init(mdesc, lookup_processor_type(read_cpuid_id()));
919 	setup_dma_zone(mdesc);
920 	sanity_check_meminfo();
921 	arm_memblock_init(mdesc);
922 
923 	paging_init(mdesc);
924 	request_standard_resources(mdesc);
925 
926 	if (mdesc->restart)
927 		arm_pm_restart = mdesc->restart;
928 
929 	unflatten_device_tree();
930 
931 	arm_dt_init_cpu_maps();
932 	psci_init();
933 #ifdef CONFIG_SMP
934 	if (is_smp()) {
935 		if (!mdesc->smp_init || !mdesc->smp_init()) {
936 			if (psci_smp_available())
937 				smp_set_ops(&psci_smp_ops);
938 			else if (mdesc->smp)
939 				smp_set_ops(mdesc->smp);
940 		}
941 		smp_init_cpus();
942 		smp_build_mpidr_hash();
943 	}
944 #endif
945 
946 	if (!is_smp())
947 		hyp_mode_check();
948 
949 	reserve_crashkernel();
950 
951 #ifdef CONFIG_MULTI_IRQ_HANDLER
952 	handle_arch_irq = mdesc->handle_irq;
953 #endif
954 
955 #ifdef CONFIG_VT
956 #if defined(CONFIG_VGA_CONSOLE)
957 	conswitchp = &vga_con;
958 #elif defined(CONFIG_DUMMY_CONSOLE)
959 	conswitchp = &dummy_con;
960 #endif
961 #endif
962 
963 	if (mdesc->init_early)
964 		mdesc->init_early();
965 }
966 
967 
968 static int __init topology_init(void)
969 {
970 	int cpu;
971 
972 	for_each_possible_cpu(cpu) {
973 		struct cpuinfo_arm *cpuinfo = &per_cpu(cpu_data, cpu);
974 		cpuinfo->cpu.hotpluggable = 1;
975 		register_cpu(&cpuinfo->cpu, cpu);
976 	}
977 
978 	return 0;
979 }
980 subsys_initcall(topology_init);
981 
982 #ifdef CONFIG_HAVE_PROC_CPU
983 static int __init proc_cpu_init(void)
984 {
985 	struct proc_dir_entry *res;
986 
987 	res = proc_mkdir("cpu", NULL);
988 	if (!res)
989 		return -ENOMEM;
990 	return 0;
991 }
992 fs_initcall(proc_cpu_init);
993 #endif
994 
995 static const char *hwcap_str[] = {
996 	"swp",
997 	"half",
998 	"thumb",
999 	"26bit",
1000 	"fastmult",
1001 	"fpa",
1002 	"vfp",
1003 	"edsp",
1004 	"java",
1005 	"iwmmxt",
1006 	"crunch",
1007 	"thumbee",
1008 	"neon",
1009 	"vfpv3",
1010 	"vfpv3d16",
1011 	"tls",
1012 	"vfpv4",
1013 	"idiva",
1014 	"idivt",
1015 	"vfpd32",
1016 	"lpae",
1017 	"evtstrm",
1018 	NULL
1019 };
1020 
1021 static const char *hwcap2_str[] = {
1022 	"aes",
1023 	"pmull",
1024 	"sha1",
1025 	"sha2",
1026 	"crc32",
1027 	NULL
1028 };
1029 
1030 static int c_show(struct seq_file *m, void *v)
1031 {
1032 	int i, j;
1033 	u32 cpuid;
1034 
1035 	for_each_online_cpu(i) {
1036 		/*
1037 		 * glibc reads /proc/cpuinfo to determine the number of
1038 		 * online processors, looking for lines beginning with
1039 		 * "processor".  Give glibc what it expects.
1040 		 */
1041 		seq_printf(m, "processor\t: %d\n", i);
1042 		cpuid = is_smp() ? per_cpu(cpu_data, i).cpuid : read_cpuid_id();
1043 		seq_printf(m, "model name\t: %s rev %d (%s)\n",
1044 			   cpu_name, cpuid & 15, elf_platform);
1045 
1046 		/* dump out the processor features */
1047 		seq_puts(m, "Features\t: ");
1048 
1049 		for (j = 0; hwcap_str[j]; j++)
1050 			if (elf_hwcap & (1 << j))
1051 				seq_printf(m, "%s ", hwcap_str[j]);
1052 
1053 		for (j = 0; hwcap2_str[j]; j++)
1054 			if (elf_hwcap2 & (1 << j))
1055 				seq_printf(m, "%s ", hwcap2_str[j]);
1056 
1057 		seq_printf(m, "\nCPU implementer\t: 0x%02x\n", cpuid >> 24);
1058 		seq_printf(m, "CPU architecture: %s\n",
1059 			   proc_arch[cpu_architecture()]);
1060 
1061 		if ((cpuid & 0x0008f000) == 0x00000000) {
1062 			/* pre-ARM7 */
1063 			seq_printf(m, "CPU part\t: %07x\n", cpuid >> 4);
1064 		} else {
1065 			if ((cpuid & 0x0008f000) == 0x00007000) {
1066 				/* ARM7 */
1067 				seq_printf(m, "CPU variant\t: 0x%02x\n",
1068 					   (cpuid >> 16) & 127);
1069 			} else {
1070 				/* post-ARM7 */
1071 				seq_printf(m, "CPU variant\t: 0x%x\n",
1072 					   (cpuid >> 20) & 15);
1073 			}
1074 			seq_printf(m, "CPU part\t: 0x%03x\n",
1075 				   (cpuid >> 4) & 0xfff);
1076 		}
1077 		seq_printf(m, "CPU revision\t: %d\n\n", cpuid & 15);
1078 	}
1079 
1080 	seq_printf(m, "Hardware\t: %s\n", machine_name);
1081 	seq_printf(m, "Revision\t: %04x\n", system_rev);
1082 	seq_printf(m, "Serial\t\t: %08x%08x\n",
1083 		   system_serial_high, system_serial_low);
1084 
1085 	return 0;
1086 }
1087 
1088 static void *c_start(struct seq_file *m, loff_t *pos)
1089 {
1090 	return *pos < 1 ? (void *)1 : NULL;
1091 }
1092 
1093 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
1094 {
1095 	++*pos;
1096 	return NULL;
1097 }
1098 
1099 static void c_stop(struct seq_file *m, void *v)
1100 {
1101 }
1102 
1103 const struct seq_operations cpuinfo_op = {
1104 	.start	= c_start,
1105 	.next	= c_next,
1106 	.stop	= c_stop,
1107 	.show	= c_show
1108 };
1109