xref: /openbmc/linux/arch/arm/kernel/setup.c (revision ff6defa6)
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 		unsigned int mmfr0;
250 
251 		/* Revised CPUID format. Read the Memory Model Feature
252 		 * Register 0 and check for VMSAv7 or PMSAv7 */
253 		asm("mrc	p15, 0, %0, c0, c1, 4"
254 		    : "=r" (mmfr0));
255 		if ((mmfr0 & 0x0000000f) >= 0x00000003 ||
256 		    (mmfr0 & 0x000000f0) >= 0x00000030)
257 			cpu_arch = CPU_ARCH_ARMv7;
258 		else if ((mmfr0 & 0x0000000f) == 0x00000002 ||
259 			 (mmfr0 & 0x000000f0) == 0x00000020)
260 			cpu_arch = CPU_ARCH_ARMv6;
261 		else
262 			cpu_arch = CPU_ARCH_UNKNOWN;
263 	} else
264 		cpu_arch = CPU_ARCH_UNKNOWN;
265 
266 	return cpu_arch;
267 }
268 #endif
269 
270 int __pure cpu_architecture(void)
271 {
272 	BUG_ON(__cpu_architecture == CPU_ARCH_UNKNOWN);
273 
274 	return __cpu_architecture;
275 }
276 
277 static int cpu_has_aliasing_icache(unsigned int arch)
278 {
279 	int aliasing_icache;
280 	unsigned int id_reg, num_sets, line_size;
281 
282 	/* PIPT caches never alias. */
283 	if (icache_is_pipt())
284 		return 0;
285 
286 	/* arch specifies the register format */
287 	switch (arch) {
288 	case CPU_ARCH_ARMv7:
289 		asm("mcr	p15, 2, %0, c0, c0, 0 @ set CSSELR"
290 		    : /* No output operands */
291 		    : "r" (1));
292 		isb();
293 		asm("mrc	p15, 1, %0, c0, c0, 0 @ read CCSIDR"
294 		    : "=r" (id_reg));
295 		line_size = 4 << ((id_reg & 0x7) + 2);
296 		num_sets = ((id_reg >> 13) & 0x7fff) + 1;
297 		aliasing_icache = (line_size * num_sets) > PAGE_SIZE;
298 		break;
299 	case CPU_ARCH_ARMv6:
300 		aliasing_icache = read_cpuid_cachetype() & (1 << 11);
301 		break;
302 	default:
303 		/* I-cache aliases will be handled by D-cache aliasing code */
304 		aliasing_icache = 0;
305 	}
306 
307 	return aliasing_icache;
308 }
309 
310 static void __init cacheid_init(void)
311 {
312 	unsigned int arch = cpu_architecture();
313 
314 	if (arch == CPU_ARCH_ARMv7M) {
315 		cacheid = 0;
316 	} else if (arch >= CPU_ARCH_ARMv6) {
317 		unsigned int cachetype = read_cpuid_cachetype();
318 		if ((cachetype & (7 << 29)) == 4 << 29) {
319 			/* ARMv7 register format */
320 			arch = CPU_ARCH_ARMv7;
321 			cacheid = CACHEID_VIPT_NONALIASING;
322 			switch (cachetype & (3 << 14)) {
323 			case (1 << 14):
324 				cacheid |= CACHEID_ASID_TAGGED;
325 				break;
326 			case (3 << 14):
327 				cacheid |= CACHEID_PIPT;
328 				break;
329 			}
330 		} else {
331 			arch = CPU_ARCH_ARMv6;
332 			if (cachetype & (1 << 23))
333 				cacheid = CACHEID_VIPT_ALIASING;
334 			else
335 				cacheid = CACHEID_VIPT_NONALIASING;
336 		}
337 		if (cpu_has_aliasing_icache(arch))
338 			cacheid |= CACHEID_VIPT_I_ALIASING;
339 	} else {
340 		cacheid = CACHEID_VIVT;
341 	}
342 
343 	pr_info("CPU: %s data cache, %s instruction cache\n",
344 		cache_is_vivt() ? "VIVT" :
345 		cache_is_vipt_aliasing() ? "VIPT aliasing" :
346 		cache_is_vipt_nonaliasing() ? "PIPT / VIPT nonaliasing" : "unknown",
347 		cache_is_vivt() ? "VIVT" :
348 		icache_is_vivt_asid_tagged() ? "VIVT ASID tagged" :
349 		icache_is_vipt_aliasing() ? "VIPT aliasing" :
350 		icache_is_pipt() ? "PIPT" :
351 		cache_is_vipt_nonaliasing() ? "VIPT nonaliasing" : "unknown");
352 }
353 
354 /*
355  * These functions re-use the assembly code in head.S, which
356  * already provide the required functionality.
357  */
358 extern struct proc_info_list *lookup_processor_type(unsigned int);
359 
360 void __init early_print(const char *str, ...)
361 {
362 	extern void printascii(const char *);
363 	char buf[256];
364 	va_list ap;
365 
366 	va_start(ap, str);
367 	vsnprintf(buf, sizeof(buf), str, ap);
368 	va_end(ap);
369 
370 #ifdef CONFIG_DEBUG_LL
371 	printascii(buf);
372 #endif
373 	printk("%s", buf);
374 }
375 
376 static void __init cpuid_init_hwcaps(void)
377 {
378 	unsigned int divide_instrs, vmsa;
379 
380 	if (cpu_architecture() < CPU_ARCH_ARMv7)
381 		return;
382 
383 	divide_instrs = (read_cpuid_ext(CPUID_EXT_ISAR0) & 0x0f000000) >> 24;
384 
385 	switch (divide_instrs) {
386 	case 2:
387 		elf_hwcap |= HWCAP_IDIVA;
388 	case 1:
389 		elf_hwcap |= HWCAP_IDIVT;
390 	}
391 
392 	/* LPAE implies atomic ldrd/strd instructions */
393 	vmsa = (read_cpuid_ext(CPUID_EXT_MMFR0) & 0xf) >> 0;
394 	if (vmsa >= 5)
395 		elf_hwcap |= HWCAP_LPAE;
396 }
397 
398 static void __init elf_hwcap_fixup(void)
399 {
400 	unsigned id = read_cpuid_id();
401 	unsigned sync_prim;
402 
403 	/*
404 	 * HWCAP_TLS is available only on 1136 r1p0 and later,
405 	 * see also kuser_get_tls_init.
406 	 */
407 	if (read_cpuid_part() == ARM_CPU_PART_ARM1136 &&
408 	    ((id >> 20) & 3) == 0) {
409 		elf_hwcap &= ~HWCAP_TLS;
410 		return;
411 	}
412 
413 	/* Verify if CPUID scheme is implemented */
414 	if ((id & 0x000f0000) != 0x000f0000)
415 		return;
416 
417 	/*
418 	 * If the CPU supports LDREX/STREX and LDREXB/STREXB,
419 	 * avoid advertising SWP; it may not be atomic with
420 	 * multiprocessing cores.
421 	 */
422 	sync_prim = ((read_cpuid_ext(CPUID_EXT_ISAR3) >> 8) & 0xf0) |
423 		    ((read_cpuid_ext(CPUID_EXT_ISAR4) >> 20) & 0x0f);
424 	if (sync_prim >= 0x13)
425 		elf_hwcap &= ~HWCAP_SWP;
426 }
427 
428 /*
429  * cpu_init - initialise one CPU.
430  *
431  * cpu_init sets up the per-CPU stacks.
432  */
433 void notrace cpu_init(void)
434 {
435 #ifndef CONFIG_CPU_V7M
436 	unsigned int cpu = smp_processor_id();
437 	struct stack *stk = &stacks[cpu];
438 
439 	if (cpu >= NR_CPUS) {
440 		pr_crit("CPU%u: bad primary CPU number\n", cpu);
441 		BUG();
442 	}
443 
444 	/*
445 	 * This only works on resume and secondary cores. For booting on the
446 	 * boot cpu, smp_prepare_boot_cpu is called after percpu area setup.
447 	 */
448 	set_my_cpu_offset(per_cpu_offset(cpu));
449 
450 	cpu_proc_init();
451 
452 	/*
453 	 * Define the placement constraint for the inline asm directive below.
454 	 * In Thumb-2, msr with an immediate value is not allowed.
455 	 */
456 #ifdef CONFIG_THUMB2_KERNEL
457 #define PLC	"r"
458 #else
459 #define PLC	"I"
460 #endif
461 
462 	/*
463 	 * setup stacks for re-entrant exception handlers
464 	 */
465 	__asm__ (
466 	"msr	cpsr_c, %1\n\t"
467 	"add	r14, %0, %2\n\t"
468 	"mov	sp, r14\n\t"
469 	"msr	cpsr_c, %3\n\t"
470 	"add	r14, %0, %4\n\t"
471 	"mov	sp, r14\n\t"
472 	"msr	cpsr_c, %5\n\t"
473 	"add	r14, %0, %6\n\t"
474 	"mov	sp, r14\n\t"
475 	"msr	cpsr_c, %7\n\t"
476 	"add	r14, %0, %8\n\t"
477 	"mov	sp, r14\n\t"
478 	"msr	cpsr_c, %9"
479 	    :
480 	    : "r" (stk),
481 	      PLC (PSR_F_BIT | PSR_I_BIT | IRQ_MODE),
482 	      "I" (offsetof(struct stack, irq[0])),
483 	      PLC (PSR_F_BIT | PSR_I_BIT | ABT_MODE),
484 	      "I" (offsetof(struct stack, abt[0])),
485 	      PLC (PSR_F_BIT | PSR_I_BIT | UND_MODE),
486 	      "I" (offsetof(struct stack, und[0])),
487 	      PLC (PSR_F_BIT | PSR_I_BIT | FIQ_MODE),
488 	      "I" (offsetof(struct stack, fiq[0])),
489 	      PLC (PSR_F_BIT | PSR_I_BIT | SVC_MODE)
490 	    : "r14");
491 #endif
492 }
493 
494 u32 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = MPIDR_INVALID };
495 
496 void __init smp_setup_processor_id(void)
497 {
498 	int i;
499 	u32 mpidr = is_smp() ? read_cpuid_mpidr() & MPIDR_HWID_BITMASK : 0;
500 	u32 cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
501 
502 	cpu_logical_map(0) = cpu;
503 	for (i = 1; i < nr_cpu_ids; ++i)
504 		cpu_logical_map(i) = i == cpu ? 0 : i;
505 
506 	/*
507 	 * clear __my_cpu_offset on boot CPU to avoid hang caused by
508 	 * using percpu variable early, for example, lockdep will
509 	 * access percpu variable inside lock_release
510 	 */
511 	set_my_cpu_offset(0);
512 
513 	pr_info("Booting Linux on physical CPU 0x%x\n", mpidr);
514 }
515 
516 struct mpidr_hash mpidr_hash;
517 #ifdef CONFIG_SMP
518 /**
519  * smp_build_mpidr_hash - Pre-compute shifts required at each affinity
520  *			  level in order to build a linear index from an
521  *			  MPIDR value. Resulting algorithm is a collision
522  *			  free hash carried out through shifting and ORing
523  */
524 static void __init smp_build_mpidr_hash(void)
525 {
526 	u32 i, affinity;
527 	u32 fs[3], bits[3], ls, mask = 0;
528 	/*
529 	 * Pre-scan the list of MPIDRS and filter out bits that do
530 	 * not contribute to affinity levels, ie they never toggle.
531 	 */
532 	for_each_possible_cpu(i)
533 		mask |= (cpu_logical_map(i) ^ cpu_logical_map(0));
534 	pr_debug("mask of set bits 0x%x\n", mask);
535 	/*
536 	 * Find and stash the last and first bit set at all affinity levels to
537 	 * check how many bits are required to represent them.
538 	 */
539 	for (i = 0; i < 3; i++) {
540 		affinity = MPIDR_AFFINITY_LEVEL(mask, i);
541 		/*
542 		 * Find the MSB bit and LSB bits position
543 		 * to determine how many bits are required
544 		 * to express the affinity level.
545 		 */
546 		ls = fls(affinity);
547 		fs[i] = affinity ? ffs(affinity) - 1 : 0;
548 		bits[i] = ls - fs[i];
549 	}
550 	/*
551 	 * An index can be created from the MPIDR by isolating the
552 	 * significant bits at each affinity level and by shifting
553 	 * them in order to compress the 24 bits values space to a
554 	 * compressed set of values. This is equivalent to hashing
555 	 * the MPIDR through shifting and ORing. It is a collision free
556 	 * hash though not minimal since some levels might contain a number
557 	 * of CPUs that is not an exact power of 2 and their bit
558 	 * representation might contain holes, eg MPIDR[7:0] = {0x2, 0x80}.
559 	 */
560 	mpidr_hash.shift_aff[0] = fs[0];
561 	mpidr_hash.shift_aff[1] = MPIDR_LEVEL_BITS + fs[1] - bits[0];
562 	mpidr_hash.shift_aff[2] = 2*MPIDR_LEVEL_BITS + fs[2] -
563 						(bits[1] + bits[0]);
564 	mpidr_hash.mask = mask;
565 	mpidr_hash.bits = bits[2] + bits[1] + bits[0];
566 	pr_debug("MPIDR hash: aff0[%u] aff1[%u] aff2[%u] mask[0x%x] bits[%u]\n",
567 				mpidr_hash.shift_aff[0],
568 				mpidr_hash.shift_aff[1],
569 				mpidr_hash.shift_aff[2],
570 				mpidr_hash.mask,
571 				mpidr_hash.bits);
572 	/*
573 	 * 4x is an arbitrary value used to warn on a hash table much bigger
574 	 * than expected on most systems.
575 	 */
576 	if (mpidr_hash_size() > 4 * num_possible_cpus())
577 		pr_warn("Large number of MPIDR hash buckets detected\n");
578 	sync_cache_w(&mpidr_hash);
579 }
580 #endif
581 
582 static void __init setup_processor(void)
583 {
584 	struct proc_info_list *list;
585 
586 	/*
587 	 * locate processor in the list of supported processor
588 	 * types.  The linker builds this table for us from the
589 	 * entries in arch/arm/mm/proc-*.S
590 	 */
591 	list = lookup_processor_type(read_cpuid_id());
592 	if (!list) {
593 		pr_err("CPU configuration botched (ID %08x), unable to continue.\n",
594 		       read_cpuid_id());
595 		while (1);
596 	}
597 
598 	cpu_name = list->cpu_name;
599 	__cpu_architecture = __get_cpu_architecture();
600 
601 #ifdef MULTI_CPU
602 	processor = *list->proc;
603 #endif
604 #ifdef MULTI_TLB
605 	cpu_tlb = *list->tlb;
606 #endif
607 #ifdef MULTI_USER
608 	cpu_user = *list->user;
609 #endif
610 #ifdef MULTI_CACHE
611 	cpu_cache = *list->cache;
612 #endif
613 
614 	pr_info("CPU: %s [%08x] revision %d (ARMv%s), cr=%08lx\n",
615 		cpu_name, read_cpuid_id(), read_cpuid_id() & 15,
616 		proc_arch[cpu_architecture()], get_cr());
617 
618 	snprintf(init_utsname()->machine, __NEW_UTS_LEN + 1, "%s%c",
619 		 list->arch_name, ENDIANNESS);
620 	snprintf(elf_platform, ELF_PLATFORM_SIZE, "%s%c",
621 		 list->elf_name, ENDIANNESS);
622 	elf_hwcap = list->elf_hwcap;
623 
624 	cpuid_init_hwcaps();
625 
626 #ifndef CONFIG_ARM_THUMB
627 	elf_hwcap &= ~(HWCAP_THUMB | HWCAP_IDIVT);
628 #endif
629 #ifdef CONFIG_MMU
630 	init_default_cache_policy(list->__cpu_mm_mmu_flags);
631 #endif
632 	erratum_a15_798181_init();
633 
634 	elf_hwcap_fixup();
635 
636 	cacheid_init();
637 	cpu_init();
638 }
639 
640 void __init dump_machine_table(void)
641 {
642 	const struct machine_desc *p;
643 
644 	early_print("Available machine support:\n\nID (hex)\tNAME\n");
645 	for_each_machine_desc(p)
646 		early_print("%08x\t%s\n", p->nr, p->name);
647 
648 	early_print("\nPlease check your kernel config and/or bootloader.\n");
649 
650 	while (true)
651 		/* can't use cpu_relax() here as it may require MMU setup */;
652 }
653 
654 int __init arm_add_memory(u64 start, u64 size)
655 {
656 	u64 aligned_start;
657 
658 	/*
659 	 * Ensure that start/size are aligned to a page boundary.
660 	 * Size is appropriately rounded down, start is rounded up.
661 	 */
662 	size -= start & ~PAGE_MASK;
663 	aligned_start = PAGE_ALIGN(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 		/* dump out the processor features */
1050 		seq_puts(m, "Features\t: ");
1051 
1052 		for (j = 0; hwcap_str[j]; j++)
1053 			if (elf_hwcap & (1 << j))
1054 				seq_printf(m, "%s ", hwcap_str[j]);
1055 
1056 		for (j = 0; hwcap2_str[j]; j++)
1057 			if (elf_hwcap2 & (1 << j))
1058 				seq_printf(m, "%s ", hwcap2_str[j]);
1059 
1060 		seq_printf(m, "\nCPU implementer\t: 0x%02x\n", cpuid >> 24);
1061 		seq_printf(m, "CPU architecture: %s\n",
1062 			   proc_arch[cpu_architecture()]);
1063 
1064 		if ((cpuid & 0x0008f000) == 0x00000000) {
1065 			/* pre-ARM7 */
1066 			seq_printf(m, "CPU part\t: %07x\n", cpuid >> 4);
1067 		} else {
1068 			if ((cpuid & 0x0008f000) == 0x00007000) {
1069 				/* ARM7 */
1070 				seq_printf(m, "CPU variant\t: 0x%02x\n",
1071 					   (cpuid >> 16) & 127);
1072 			} else {
1073 				/* post-ARM7 */
1074 				seq_printf(m, "CPU variant\t: 0x%x\n",
1075 					   (cpuid >> 20) & 15);
1076 			}
1077 			seq_printf(m, "CPU part\t: 0x%03x\n",
1078 				   (cpuid >> 4) & 0xfff);
1079 		}
1080 		seq_printf(m, "CPU revision\t: %d\n\n", cpuid & 15);
1081 	}
1082 
1083 	seq_printf(m, "Hardware\t: %s\n", machine_name);
1084 	seq_printf(m, "Revision\t: %04x\n", system_rev);
1085 	seq_printf(m, "Serial\t\t: %08x%08x\n",
1086 		   system_serial_high, system_serial_low);
1087 
1088 	return 0;
1089 }
1090 
1091 static void *c_start(struct seq_file *m, loff_t *pos)
1092 {
1093 	return *pos < 1 ? (void *)1 : NULL;
1094 }
1095 
1096 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
1097 {
1098 	++*pos;
1099 	return NULL;
1100 }
1101 
1102 static void c_stop(struct seq_file *m, void *v)
1103 {
1104 }
1105 
1106 const struct seq_operations cpuinfo_op = {
1107 	.start	= c_start,
1108 	.next	= c_next,
1109 	.stop	= c_stop,
1110 	.show	= c_show
1111 };
1112