xref: /openbmc/linux/arch/arm/kernel/setup.c (revision 8e694cd2)
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/efi.h>
11 #include <linux/export.h>
12 #include <linux/kernel.h>
13 #include <linux/stddef.h>
14 #include <linux/ioport.h>
15 #include <linux/delay.h>
16 #include <linux/utsname.h>
17 #include <linux/initrd.h>
18 #include <linux/console.h>
19 #include <linux/bootmem.h>
20 #include <linux/seq_file.h>
21 #include <linux/screen_info.h>
22 #include <linux/of_iommu.h>
23 #include <linux/of_platform.h>
24 #include <linux/init.h>
25 #include <linux/kexec.h>
26 #include <linux/of_fdt.h>
27 #include <linux/cpu.h>
28 #include <linux/interrupt.h>
29 #include <linux/smp.h>
30 #include <linux/proc_fs.h>
31 #include <linux/memblock.h>
32 #include <linux/bug.h>
33 #include <linux/compiler.h>
34 #include <linux/sort.h>
35 #include <linux/psci.h>
36 
37 #include <asm/unified.h>
38 #include <asm/cp15.h>
39 #include <asm/cpu.h>
40 #include <asm/cputype.h>
41 #include <asm/efi.h>
42 #include <asm/elf.h>
43 #include <asm/early_ioremap.h>
44 #include <asm/fixmap.h>
45 #include <asm/procinfo.h>
46 #include <asm/psci.h>
47 #include <asm/sections.h>
48 #include <asm/setup.h>
49 #include <asm/smp_plat.h>
50 #include <asm/mach-types.h>
51 #include <asm/cacheflush.h>
52 #include <asm/cachetype.h>
53 #include <asm/tlbflush.h>
54 #include <asm/xen/hypervisor.h>
55 
56 #include <asm/prom.h>
57 #include <asm/mach/arch.h>
58 #include <asm/mach/irq.h>
59 #include <asm/mach/time.h>
60 #include <asm/system_info.h>
61 #include <asm/system_misc.h>
62 #include <asm/traps.h>
63 #include <asm/unwind.h>
64 #include <asm/memblock.h>
65 #include <asm/virt.h>
66 
67 #include "atags.h"
68 
69 
70 #if defined(CONFIG_FPE_NWFPE) || defined(CONFIG_FPE_FASTFPE)
71 char fpe_type[8];
72 
73 static int __init fpe_setup(char *line)
74 {
75 	memcpy(fpe_type, line, 8);
76 	return 1;
77 }
78 
79 __setup("fpe=", fpe_setup);
80 #endif
81 
82 extern void init_default_cache_policy(unsigned long);
83 extern void paging_init(const struct machine_desc *desc);
84 extern void early_paging_init(const struct machine_desc *);
85 extern void sanity_check_meminfo(void);
86 extern enum reboot_mode reboot_mode;
87 extern void setup_dma_zone(const struct machine_desc *desc);
88 
89 unsigned int processor_id;
90 EXPORT_SYMBOL(processor_id);
91 unsigned int __machine_arch_type __read_mostly;
92 EXPORT_SYMBOL(__machine_arch_type);
93 unsigned int cacheid __read_mostly;
94 EXPORT_SYMBOL(cacheid);
95 
96 unsigned int __atags_pointer __initdata;
97 
98 unsigned int system_rev;
99 EXPORT_SYMBOL(system_rev);
100 
101 const char *system_serial;
102 EXPORT_SYMBOL(system_serial);
103 
104 unsigned int system_serial_low;
105 EXPORT_SYMBOL(system_serial_low);
106 
107 unsigned int system_serial_high;
108 EXPORT_SYMBOL(system_serial_high);
109 
110 unsigned int elf_hwcap __read_mostly;
111 EXPORT_SYMBOL(elf_hwcap);
112 
113 unsigned int elf_hwcap2 __read_mostly;
114 EXPORT_SYMBOL(elf_hwcap2);
115 
116 
117 #ifdef MULTI_CPU
118 struct processor processor __read_mostly;
119 #endif
120 #ifdef MULTI_TLB
121 struct cpu_tlb_fns cpu_tlb __read_mostly;
122 #endif
123 #ifdef MULTI_USER
124 struct cpu_user_fns cpu_user __read_mostly;
125 #endif
126 #ifdef MULTI_CACHE
127 struct cpu_cache_fns cpu_cache __read_mostly;
128 #endif
129 #ifdef CONFIG_OUTER_CACHE
130 struct outer_cache_fns outer_cache __read_mostly;
131 EXPORT_SYMBOL(outer_cache);
132 #endif
133 
134 /*
135  * Cached cpu_architecture() result for use by assembler code.
136  * C code should use the cpu_architecture() function instead of accessing this
137  * variable directly.
138  */
139 int __cpu_architecture __read_mostly = CPU_ARCH_UNKNOWN;
140 
141 struct stack {
142 	u32 irq[3];
143 	u32 abt[3];
144 	u32 und[3];
145 	u32 fiq[3];
146 } ____cacheline_aligned;
147 
148 #ifndef CONFIG_CPU_V7M
149 static struct stack stacks[NR_CPUS];
150 #endif
151 
152 char elf_platform[ELF_PLATFORM_SIZE];
153 EXPORT_SYMBOL(elf_platform);
154 
155 static const char *cpu_name;
156 static const char *machine_name;
157 static char __initdata cmd_line[COMMAND_LINE_SIZE];
158 const struct machine_desc *machine_desc __initdata;
159 
160 static union { char c[4]; unsigned long l; } endian_test __initdata = { { 'l', '?', '?', 'b' } };
161 #define ENDIANNESS ((char)endian_test.l)
162 
163 DEFINE_PER_CPU(struct cpuinfo_arm, cpu_data);
164 
165 /*
166  * Standard memory resources
167  */
168 static struct resource mem_res[] = {
169 	{
170 		.name = "Video RAM",
171 		.start = 0,
172 		.end = 0,
173 		.flags = IORESOURCE_MEM
174 	},
175 	{
176 		.name = "Kernel code",
177 		.start = 0,
178 		.end = 0,
179 		.flags = IORESOURCE_SYSTEM_RAM
180 	},
181 	{
182 		.name = "Kernel data",
183 		.start = 0,
184 		.end = 0,
185 		.flags = IORESOURCE_SYSTEM_RAM
186 	}
187 };
188 
189 #define video_ram   mem_res[0]
190 #define kernel_code mem_res[1]
191 #define kernel_data mem_res[2]
192 
193 static struct resource io_res[] = {
194 	{
195 		.name = "reserved",
196 		.start = 0x3bc,
197 		.end = 0x3be,
198 		.flags = IORESOURCE_IO | IORESOURCE_BUSY
199 	},
200 	{
201 		.name = "reserved",
202 		.start = 0x378,
203 		.end = 0x37f,
204 		.flags = IORESOURCE_IO | IORESOURCE_BUSY
205 	},
206 	{
207 		.name = "reserved",
208 		.start = 0x278,
209 		.end = 0x27f,
210 		.flags = IORESOURCE_IO | IORESOURCE_BUSY
211 	}
212 };
213 
214 #define lp0 io_res[0]
215 #define lp1 io_res[1]
216 #define lp2 io_res[2]
217 
218 static const char *proc_arch[] = {
219 	"undefined/unknown",
220 	"3",
221 	"4",
222 	"4T",
223 	"5",
224 	"5T",
225 	"5TE",
226 	"5TEJ",
227 	"6TEJ",
228 	"7",
229 	"7M",
230 	"?(12)",
231 	"?(13)",
232 	"?(14)",
233 	"?(15)",
234 	"?(16)",
235 	"?(17)",
236 };
237 
238 #ifdef CONFIG_CPU_V7M
239 static int __get_cpu_architecture(void)
240 {
241 	return CPU_ARCH_ARMv7M;
242 }
243 #else
244 static int __get_cpu_architecture(void)
245 {
246 	int cpu_arch;
247 
248 	if ((read_cpuid_id() & 0x0008f000) == 0) {
249 		cpu_arch = CPU_ARCH_UNKNOWN;
250 	} else if ((read_cpuid_id() & 0x0008f000) == 0x00007000) {
251 		cpu_arch = (read_cpuid_id() & (1 << 23)) ? CPU_ARCH_ARMv4T : CPU_ARCH_ARMv3;
252 	} else if ((read_cpuid_id() & 0x00080000) == 0x00000000) {
253 		cpu_arch = (read_cpuid_id() >> 16) & 7;
254 		if (cpu_arch)
255 			cpu_arch += CPU_ARCH_ARMv3;
256 	} else if ((read_cpuid_id() & 0x000f0000) == 0x000f0000) {
257 		/* Revised CPUID format. Read the Memory Model Feature
258 		 * Register 0 and check for VMSAv7 or PMSAv7 */
259 		unsigned int mmfr0 = read_cpuid_ext(CPUID_EXT_MMFR0);
260 		if ((mmfr0 & 0x0000000f) >= 0x00000003 ||
261 		    (mmfr0 & 0x000000f0) >= 0x00000030)
262 			cpu_arch = CPU_ARCH_ARMv7;
263 		else if ((mmfr0 & 0x0000000f) == 0x00000002 ||
264 			 (mmfr0 & 0x000000f0) == 0x00000020)
265 			cpu_arch = CPU_ARCH_ARMv6;
266 		else
267 			cpu_arch = CPU_ARCH_UNKNOWN;
268 	} else
269 		cpu_arch = CPU_ARCH_UNKNOWN;
270 
271 	return cpu_arch;
272 }
273 #endif
274 
275 int __pure cpu_architecture(void)
276 {
277 	BUG_ON(__cpu_architecture == CPU_ARCH_UNKNOWN);
278 
279 	return __cpu_architecture;
280 }
281 
282 static int cpu_has_aliasing_icache(unsigned int arch)
283 {
284 	int aliasing_icache;
285 	unsigned int id_reg, num_sets, line_size;
286 
287 	/* PIPT caches never alias. */
288 	if (icache_is_pipt())
289 		return 0;
290 
291 	/* arch specifies the register format */
292 	switch (arch) {
293 	case CPU_ARCH_ARMv7:
294 		asm("mcr	p15, 2, %0, c0, c0, 0 @ set CSSELR"
295 		    : /* No output operands */
296 		    : "r" (1));
297 		isb();
298 		asm("mrc	p15, 1, %0, c0, c0, 0 @ read CCSIDR"
299 		    : "=r" (id_reg));
300 		line_size = 4 << ((id_reg & 0x7) + 2);
301 		num_sets = ((id_reg >> 13) & 0x7fff) + 1;
302 		aliasing_icache = (line_size * num_sets) > PAGE_SIZE;
303 		break;
304 	case CPU_ARCH_ARMv6:
305 		aliasing_icache = read_cpuid_cachetype() & (1 << 11);
306 		break;
307 	default:
308 		/* I-cache aliases will be handled by D-cache aliasing code */
309 		aliasing_icache = 0;
310 	}
311 
312 	return aliasing_icache;
313 }
314 
315 static void __init cacheid_init(void)
316 {
317 	unsigned int arch = cpu_architecture();
318 
319 	if (arch == CPU_ARCH_ARMv7M) {
320 		cacheid = 0;
321 	} else if (arch >= CPU_ARCH_ARMv6) {
322 		unsigned int cachetype = read_cpuid_cachetype();
323 		if ((cachetype & (7 << 29)) == 4 << 29) {
324 			/* ARMv7 register format */
325 			arch = CPU_ARCH_ARMv7;
326 			cacheid = CACHEID_VIPT_NONALIASING;
327 			switch (cachetype & (3 << 14)) {
328 			case (1 << 14):
329 				cacheid |= CACHEID_ASID_TAGGED;
330 				break;
331 			case (3 << 14):
332 				cacheid |= CACHEID_PIPT;
333 				break;
334 			}
335 		} else {
336 			arch = CPU_ARCH_ARMv6;
337 			if (cachetype & (1 << 23))
338 				cacheid = CACHEID_VIPT_ALIASING;
339 			else
340 				cacheid = CACHEID_VIPT_NONALIASING;
341 		}
342 		if (cpu_has_aliasing_icache(arch))
343 			cacheid |= CACHEID_VIPT_I_ALIASING;
344 	} else {
345 		cacheid = CACHEID_VIVT;
346 	}
347 
348 	pr_info("CPU: %s data cache, %s instruction cache\n",
349 		cache_is_vivt() ? "VIVT" :
350 		cache_is_vipt_aliasing() ? "VIPT aliasing" :
351 		cache_is_vipt_nonaliasing() ? "PIPT / VIPT nonaliasing" : "unknown",
352 		cache_is_vivt() ? "VIVT" :
353 		icache_is_vivt_asid_tagged() ? "VIVT ASID tagged" :
354 		icache_is_vipt_aliasing() ? "VIPT aliasing" :
355 		icache_is_pipt() ? "PIPT" :
356 		cache_is_vipt_nonaliasing() ? "VIPT nonaliasing" : "unknown");
357 }
358 
359 /*
360  * These functions re-use the assembly code in head.S, which
361  * already provide the required functionality.
362  */
363 extern struct proc_info_list *lookup_processor_type(unsigned int);
364 
365 void __init early_print(const char *str, ...)
366 {
367 	extern void printascii(const char *);
368 	char buf[256];
369 	va_list ap;
370 
371 	va_start(ap, str);
372 	vsnprintf(buf, sizeof(buf), str, ap);
373 	va_end(ap);
374 
375 #ifdef CONFIG_DEBUG_LL
376 	printascii(buf);
377 #endif
378 	printk("%s", buf);
379 }
380 
381 #ifdef CONFIG_ARM_PATCH_IDIV
382 
383 static inline u32 __attribute_const__ sdiv_instruction(void)
384 {
385 	if (IS_ENABLED(CONFIG_THUMB2_KERNEL)) {
386 		/* "sdiv r0, r0, r1" */
387 		u32 insn = __opcode_thumb32_compose(0xfb90, 0xf0f1);
388 		return __opcode_to_mem_thumb32(insn);
389 	}
390 
391 	/* "sdiv r0, r0, r1" */
392 	return __opcode_to_mem_arm(0xe710f110);
393 }
394 
395 static inline u32 __attribute_const__ udiv_instruction(void)
396 {
397 	if (IS_ENABLED(CONFIG_THUMB2_KERNEL)) {
398 		/* "udiv r0, r0, r1" */
399 		u32 insn = __opcode_thumb32_compose(0xfbb0, 0xf0f1);
400 		return __opcode_to_mem_thumb32(insn);
401 	}
402 
403 	/* "udiv r0, r0, r1" */
404 	return __opcode_to_mem_arm(0xe730f110);
405 }
406 
407 static inline u32 __attribute_const__ bx_lr_instruction(void)
408 {
409 	if (IS_ENABLED(CONFIG_THUMB2_KERNEL)) {
410 		/* "bx lr; nop" */
411 		u32 insn = __opcode_thumb32_compose(0x4770, 0x46c0);
412 		return __opcode_to_mem_thumb32(insn);
413 	}
414 
415 	/* "bx lr" */
416 	return __opcode_to_mem_arm(0xe12fff1e);
417 }
418 
419 static void __init patch_aeabi_idiv(void)
420 {
421 	extern void __aeabi_uidiv(void);
422 	extern void __aeabi_idiv(void);
423 	uintptr_t fn_addr;
424 	unsigned int mask;
425 
426 	mask = IS_ENABLED(CONFIG_THUMB2_KERNEL) ? HWCAP_IDIVT : HWCAP_IDIVA;
427 	if (!(elf_hwcap & mask))
428 		return;
429 
430 	pr_info("CPU: div instructions available: patching division code\n");
431 
432 	fn_addr = ((uintptr_t)&__aeabi_uidiv) & ~1;
433 	asm ("" : "+g" (fn_addr));
434 	((u32 *)fn_addr)[0] = udiv_instruction();
435 	((u32 *)fn_addr)[1] = bx_lr_instruction();
436 	flush_icache_range(fn_addr, fn_addr + 8);
437 
438 	fn_addr = ((uintptr_t)&__aeabi_idiv) & ~1;
439 	asm ("" : "+g" (fn_addr));
440 	((u32 *)fn_addr)[0] = sdiv_instruction();
441 	((u32 *)fn_addr)[1] = bx_lr_instruction();
442 	flush_icache_range(fn_addr, fn_addr + 8);
443 }
444 
445 #else
446 static inline void patch_aeabi_idiv(void) { }
447 #endif
448 
449 static void __init cpuid_init_hwcaps(void)
450 {
451 	int block;
452 	u32 isar5;
453 
454 	if (cpu_architecture() < CPU_ARCH_ARMv7)
455 		return;
456 
457 	block = cpuid_feature_extract(CPUID_EXT_ISAR0, 24);
458 	if (block >= 2)
459 		elf_hwcap |= HWCAP_IDIVA;
460 	if (block >= 1)
461 		elf_hwcap |= HWCAP_IDIVT;
462 
463 	/* LPAE implies atomic ldrd/strd instructions */
464 	block = cpuid_feature_extract(CPUID_EXT_MMFR0, 0);
465 	if (block >= 5)
466 		elf_hwcap |= HWCAP_LPAE;
467 
468 	/* check for supported v8 Crypto instructions */
469 	isar5 = read_cpuid_ext(CPUID_EXT_ISAR5);
470 
471 	block = cpuid_feature_extract_field(isar5, 4);
472 	if (block >= 2)
473 		elf_hwcap2 |= HWCAP2_PMULL;
474 	if (block >= 1)
475 		elf_hwcap2 |= HWCAP2_AES;
476 
477 	block = cpuid_feature_extract_field(isar5, 8);
478 	if (block >= 1)
479 		elf_hwcap2 |= HWCAP2_SHA1;
480 
481 	block = cpuid_feature_extract_field(isar5, 12);
482 	if (block >= 1)
483 		elf_hwcap2 |= HWCAP2_SHA2;
484 
485 	block = cpuid_feature_extract_field(isar5, 16);
486 	if (block >= 1)
487 		elf_hwcap2 |= HWCAP2_CRC32;
488 }
489 
490 static void __init elf_hwcap_fixup(void)
491 {
492 	unsigned id = read_cpuid_id();
493 
494 	/*
495 	 * HWCAP_TLS is available only on 1136 r1p0 and later,
496 	 * see also kuser_get_tls_init.
497 	 */
498 	if (read_cpuid_part() == ARM_CPU_PART_ARM1136 &&
499 	    ((id >> 20) & 3) == 0) {
500 		elf_hwcap &= ~HWCAP_TLS;
501 		return;
502 	}
503 
504 	/* Verify if CPUID scheme is implemented */
505 	if ((id & 0x000f0000) != 0x000f0000)
506 		return;
507 
508 	/*
509 	 * If the CPU supports LDREX/STREX and LDREXB/STREXB,
510 	 * avoid advertising SWP; it may not be atomic with
511 	 * multiprocessing cores.
512 	 */
513 	if (cpuid_feature_extract(CPUID_EXT_ISAR3, 12) > 1 ||
514 	    (cpuid_feature_extract(CPUID_EXT_ISAR3, 12) == 1 &&
515 	     cpuid_feature_extract(CPUID_EXT_ISAR4, 20) >= 3))
516 		elf_hwcap &= ~HWCAP_SWP;
517 }
518 
519 /*
520  * cpu_init - initialise one CPU.
521  *
522  * cpu_init sets up the per-CPU stacks.
523  */
524 void notrace cpu_init(void)
525 {
526 #ifndef CONFIG_CPU_V7M
527 	unsigned int cpu = smp_processor_id();
528 	struct stack *stk = &stacks[cpu];
529 
530 	if (cpu >= NR_CPUS) {
531 		pr_crit("CPU%u: bad primary CPU number\n", cpu);
532 		BUG();
533 	}
534 
535 	/*
536 	 * This only works on resume and secondary cores. For booting on the
537 	 * boot cpu, smp_prepare_boot_cpu is called after percpu area setup.
538 	 */
539 	set_my_cpu_offset(per_cpu_offset(cpu));
540 
541 	cpu_proc_init();
542 
543 	/*
544 	 * Define the placement constraint for the inline asm directive below.
545 	 * In Thumb-2, msr with an immediate value is not allowed.
546 	 */
547 #ifdef CONFIG_THUMB2_KERNEL
548 #define PLC	"r"
549 #else
550 #define PLC	"I"
551 #endif
552 
553 	/*
554 	 * setup stacks for re-entrant exception handlers
555 	 */
556 	__asm__ (
557 	"msr	cpsr_c, %1\n\t"
558 	"add	r14, %0, %2\n\t"
559 	"mov	sp, r14\n\t"
560 	"msr	cpsr_c, %3\n\t"
561 	"add	r14, %0, %4\n\t"
562 	"mov	sp, r14\n\t"
563 	"msr	cpsr_c, %5\n\t"
564 	"add	r14, %0, %6\n\t"
565 	"mov	sp, r14\n\t"
566 	"msr	cpsr_c, %7\n\t"
567 	"add	r14, %0, %8\n\t"
568 	"mov	sp, r14\n\t"
569 	"msr	cpsr_c, %9"
570 	    :
571 	    : "r" (stk),
572 	      PLC (PSR_F_BIT | PSR_I_BIT | IRQ_MODE),
573 	      "I" (offsetof(struct stack, irq[0])),
574 	      PLC (PSR_F_BIT | PSR_I_BIT | ABT_MODE),
575 	      "I" (offsetof(struct stack, abt[0])),
576 	      PLC (PSR_F_BIT | PSR_I_BIT | UND_MODE),
577 	      "I" (offsetof(struct stack, und[0])),
578 	      PLC (PSR_F_BIT | PSR_I_BIT | FIQ_MODE),
579 	      "I" (offsetof(struct stack, fiq[0])),
580 	      PLC (PSR_F_BIT | PSR_I_BIT | SVC_MODE)
581 	    : "r14");
582 #endif
583 }
584 
585 u32 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = MPIDR_INVALID };
586 
587 void __init smp_setup_processor_id(void)
588 {
589 	int i;
590 	u32 mpidr = is_smp() ? read_cpuid_mpidr() & MPIDR_HWID_BITMASK : 0;
591 	u32 cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
592 
593 	cpu_logical_map(0) = cpu;
594 	for (i = 1; i < nr_cpu_ids; ++i)
595 		cpu_logical_map(i) = i == cpu ? 0 : i;
596 
597 	/*
598 	 * clear __my_cpu_offset on boot CPU to avoid hang caused by
599 	 * using percpu variable early, for example, lockdep will
600 	 * access percpu variable inside lock_release
601 	 */
602 	set_my_cpu_offset(0);
603 
604 	pr_info("Booting Linux on physical CPU 0x%x\n", mpidr);
605 }
606 
607 struct mpidr_hash mpidr_hash;
608 #ifdef CONFIG_SMP
609 /**
610  * smp_build_mpidr_hash - Pre-compute shifts required at each affinity
611  *			  level in order to build a linear index from an
612  *			  MPIDR value. Resulting algorithm is a collision
613  *			  free hash carried out through shifting and ORing
614  */
615 static void __init smp_build_mpidr_hash(void)
616 {
617 	u32 i, affinity;
618 	u32 fs[3], bits[3], ls, mask = 0;
619 	/*
620 	 * Pre-scan the list of MPIDRS and filter out bits that do
621 	 * not contribute to affinity levels, ie they never toggle.
622 	 */
623 	for_each_possible_cpu(i)
624 		mask |= (cpu_logical_map(i) ^ cpu_logical_map(0));
625 	pr_debug("mask of set bits 0x%x\n", mask);
626 	/*
627 	 * Find and stash the last and first bit set at all affinity levels to
628 	 * check how many bits are required to represent them.
629 	 */
630 	for (i = 0; i < 3; i++) {
631 		affinity = MPIDR_AFFINITY_LEVEL(mask, i);
632 		/*
633 		 * Find the MSB bit and LSB bits position
634 		 * to determine how many bits are required
635 		 * to express the affinity level.
636 		 */
637 		ls = fls(affinity);
638 		fs[i] = affinity ? ffs(affinity) - 1 : 0;
639 		bits[i] = ls - fs[i];
640 	}
641 	/*
642 	 * An index can be created from the MPIDR by isolating the
643 	 * significant bits at each affinity level and by shifting
644 	 * them in order to compress the 24 bits values space to a
645 	 * compressed set of values. This is equivalent to hashing
646 	 * the MPIDR through shifting and ORing. It is a collision free
647 	 * hash though not minimal since some levels might contain a number
648 	 * of CPUs that is not an exact power of 2 and their bit
649 	 * representation might contain holes, eg MPIDR[7:0] = {0x2, 0x80}.
650 	 */
651 	mpidr_hash.shift_aff[0] = fs[0];
652 	mpidr_hash.shift_aff[1] = MPIDR_LEVEL_BITS + fs[1] - bits[0];
653 	mpidr_hash.shift_aff[2] = 2*MPIDR_LEVEL_BITS + fs[2] -
654 						(bits[1] + bits[0]);
655 	mpidr_hash.mask = mask;
656 	mpidr_hash.bits = bits[2] + bits[1] + bits[0];
657 	pr_debug("MPIDR hash: aff0[%u] aff1[%u] aff2[%u] mask[0x%x] bits[%u]\n",
658 				mpidr_hash.shift_aff[0],
659 				mpidr_hash.shift_aff[1],
660 				mpidr_hash.shift_aff[2],
661 				mpidr_hash.mask,
662 				mpidr_hash.bits);
663 	/*
664 	 * 4x is an arbitrary value used to warn on a hash table much bigger
665 	 * than expected on most systems.
666 	 */
667 	if (mpidr_hash_size() > 4 * num_possible_cpus())
668 		pr_warn("Large number of MPIDR hash buckets detected\n");
669 	sync_cache_w(&mpidr_hash);
670 }
671 #endif
672 
673 static void __init setup_processor(void)
674 {
675 	struct proc_info_list *list;
676 
677 	/*
678 	 * locate processor in the list of supported processor
679 	 * types.  The linker builds this table for us from the
680 	 * entries in arch/arm/mm/proc-*.S
681 	 */
682 	list = lookup_processor_type(read_cpuid_id());
683 	if (!list) {
684 		pr_err("CPU configuration botched (ID %08x), unable to continue.\n",
685 		       read_cpuid_id());
686 		while (1);
687 	}
688 
689 	cpu_name = list->cpu_name;
690 	__cpu_architecture = __get_cpu_architecture();
691 
692 #ifdef MULTI_CPU
693 	processor = *list->proc;
694 #endif
695 #ifdef MULTI_TLB
696 	cpu_tlb = *list->tlb;
697 #endif
698 #ifdef MULTI_USER
699 	cpu_user = *list->user;
700 #endif
701 #ifdef MULTI_CACHE
702 	cpu_cache = *list->cache;
703 #endif
704 
705 	pr_info("CPU: %s [%08x] revision %d (ARMv%s), cr=%08lx\n",
706 		cpu_name, read_cpuid_id(), read_cpuid_id() & 15,
707 		proc_arch[cpu_architecture()], get_cr());
708 
709 	snprintf(init_utsname()->machine, __NEW_UTS_LEN + 1, "%s%c",
710 		 list->arch_name, ENDIANNESS);
711 	snprintf(elf_platform, ELF_PLATFORM_SIZE, "%s%c",
712 		 list->elf_name, ENDIANNESS);
713 	elf_hwcap = list->elf_hwcap;
714 
715 	cpuid_init_hwcaps();
716 	patch_aeabi_idiv();
717 
718 #ifndef CONFIG_ARM_THUMB
719 	elf_hwcap &= ~(HWCAP_THUMB | HWCAP_IDIVT);
720 #endif
721 #ifdef CONFIG_MMU
722 	init_default_cache_policy(list->__cpu_mm_mmu_flags);
723 #endif
724 	erratum_a15_798181_init();
725 
726 	elf_hwcap_fixup();
727 
728 	cacheid_init();
729 	cpu_init();
730 }
731 
732 void __init dump_machine_table(void)
733 {
734 	const struct machine_desc *p;
735 
736 	early_print("Available machine support:\n\nID (hex)\tNAME\n");
737 	for_each_machine_desc(p)
738 		early_print("%08x\t%s\n", p->nr, p->name);
739 
740 	early_print("\nPlease check your kernel config and/or bootloader.\n");
741 
742 	while (true)
743 		/* can't use cpu_relax() here as it may require MMU setup */;
744 }
745 
746 int __init arm_add_memory(u64 start, u64 size)
747 {
748 	u64 aligned_start;
749 
750 	/*
751 	 * Ensure that start/size are aligned to a page boundary.
752 	 * Size is rounded down, start is rounded up.
753 	 */
754 	aligned_start = PAGE_ALIGN(start);
755 	if (aligned_start > start + size)
756 		size = 0;
757 	else
758 		size -= aligned_start - start;
759 
760 #ifndef CONFIG_ARCH_PHYS_ADDR_T_64BIT
761 	if (aligned_start > ULONG_MAX) {
762 		pr_crit("Ignoring memory at 0x%08llx outside 32-bit physical address space\n",
763 			(long long)start);
764 		return -EINVAL;
765 	}
766 
767 	if (aligned_start + size > ULONG_MAX) {
768 		pr_crit("Truncating memory at 0x%08llx to fit in 32-bit physical address space\n",
769 			(long long)start);
770 		/*
771 		 * To ensure bank->start + bank->size is representable in
772 		 * 32 bits, we use ULONG_MAX as the upper limit rather than 4GB.
773 		 * This means we lose a page after masking.
774 		 */
775 		size = ULONG_MAX - aligned_start;
776 	}
777 #endif
778 
779 	if (aligned_start < PHYS_OFFSET) {
780 		if (aligned_start + size <= PHYS_OFFSET) {
781 			pr_info("Ignoring memory below PHYS_OFFSET: 0x%08llx-0x%08llx\n",
782 				aligned_start, aligned_start + size);
783 			return -EINVAL;
784 		}
785 
786 		pr_info("Ignoring memory below PHYS_OFFSET: 0x%08llx-0x%08llx\n",
787 			aligned_start, (u64)PHYS_OFFSET);
788 
789 		size -= PHYS_OFFSET - aligned_start;
790 		aligned_start = PHYS_OFFSET;
791 	}
792 
793 	start = aligned_start;
794 	size = size & ~(phys_addr_t)(PAGE_SIZE - 1);
795 
796 	/*
797 	 * Check whether this memory region has non-zero size or
798 	 * invalid node number.
799 	 */
800 	if (size == 0)
801 		return -EINVAL;
802 
803 	memblock_add(start, size);
804 	return 0;
805 }
806 
807 /*
808  * Pick out the memory size.  We look for mem=size@start,
809  * where start and size are "size[KkMm]"
810  */
811 
812 static int __init early_mem(char *p)
813 {
814 	static int usermem __initdata = 0;
815 	u64 size;
816 	u64 start;
817 	char *endp;
818 
819 	/*
820 	 * If the user specifies memory size, we
821 	 * blow away any automatically generated
822 	 * size.
823 	 */
824 	if (usermem == 0) {
825 		usermem = 1;
826 		memblock_remove(memblock_start_of_DRAM(),
827 			memblock_end_of_DRAM() - memblock_start_of_DRAM());
828 	}
829 
830 	start = PHYS_OFFSET;
831 	size  = memparse(p, &endp);
832 	if (*endp == '@')
833 		start = memparse(endp + 1, NULL);
834 
835 	arm_add_memory(start, size);
836 
837 	return 0;
838 }
839 early_param("mem", early_mem);
840 
841 static void __init request_standard_resources(const struct machine_desc *mdesc)
842 {
843 	struct memblock_region *region;
844 	struct resource *res;
845 
846 	kernel_code.start   = virt_to_phys(_text);
847 	kernel_code.end     = virt_to_phys(_etext - 1);
848 	kernel_data.start   = virt_to_phys(_sdata);
849 	kernel_data.end     = virt_to_phys(_end - 1);
850 
851 	for_each_memblock(memory, region) {
852 		res = memblock_virt_alloc(sizeof(*res), 0);
853 		res->name  = "System RAM";
854 		res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
855 		res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
856 		res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
857 
858 		request_resource(&iomem_resource, res);
859 
860 		if (kernel_code.start >= res->start &&
861 		    kernel_code.end <= res->end)
862 			request_resource(res, &kernel_code);
863 		if (kernel_data.start >= res->start &&
864 		    kernel_data.end <= res->end)
865 			request_resource(res, &kernel_data);
866 	}
867 
868 	if (mdesc->video_start) {
869 		video_ram.start = mdesc->video_start;
870 		video_ram.end   = mdesc->video_end;
871 		request_resource(&iomem_resource, &video_ram);
872 	}
873 
874 	/*
875 	 * Some machines don't have the possibility of ever
876 	 * possessing lp0, lp1 or lp2
877 	 */
878 	if (mdesc->reserve_lp0)
879 		request_resource(&ioport_resource, &lp0);
880 	if (mdesc->reserve_lp1)
881 		request_resource(&ioport_resource, &lp1);
882 	if (mdesc->reserve_lp2)
883 		request_resource(&ioport_resource, &lp2);
884 }
885 
886 #if defined(CONFIG_VGA_CONSOLE) || defined(CONFIG_DUMMY_CONSOLE) || \
887     defined(CONFIG_EFI)
888 struct screen_info screen_info = {
889  .orig_video_lines	= 30,
890  .orig_video_cols	= 80,
891  .orig_video_mode	= 0,
892  .orig_video_ega_bx	= 0,
893  .orig_video_isVGA	= 1,
894  .orig_video_points	= 8
895 };
896 #endif
897 
898 static int __init customize_machine(void)
899 {
900 	/*
901 	 * customizes platform devices, or adds new ones
902 	 * On DT based machines, we fall back to populating the
903 	 * machine from the device tree, if no callback is provided,
904 	 * otherwise we would always need an init_machine callback.
905 	 */
906 	of_iommu_init();
907 	if (machine_desc->init_machine)
908 		machine_desc->init_machine();
909 #ifdef CONFIG_OF
910 	else
911 		of_platform_populate(NULL, of_default_bus_match_table,
912 					NULL, NULL);
913 #endif
914 	return 0;
915 }
916 arch_initcall(customize_machine);
917 
918 static int __init init_machine_late(void)
919 {
920 	struct device_node *root;
921 	int ret;
922 
923 	if (machine_desc->init_late)
924 		machine_desc->init_late();
925 
926 	root = of_find_node_by_path("/");
927 	if (root) {
928 		ret = of_property_read_string(root, "serial-number",
929 					      &system_serial);
930 		if (ret)
931 			system_serial = NULL;
932 	}
933 
934 	if (!system_serial)
935 		system_serial = kasprintf(GFP_KERNEL, "%08x%08x",
936 					  system_serial_high,
937 					  system_serial_low);
938 
939 	return 0;
940 }
941 late_initcall(init_machine_late);
942 
943 #ifdef CONFIG_KEXEC
944 /*
945  * The crash region must be aligned to 128MB to avoid
946  * zImage relocating below the reserved region.
947  */
948 #define CRASH_ALIGN	(128 << 20)
949 
950 static inline unsigned long long get_total_mem(void)
951 {
952 	unsigned long total;
953 
954 	total = max_low_pfn - min_low_pfn;
955 	return total << PAGE_SHIFT;
956 }
957 
958 /**
959  * reserve_crashkernel() - reserves memory are for crash kernel
960  *
961  * This function reserves memory area given in "crashkernel=" kernel command
962  * line parameter. The memory reserved is used by a dump capture kernel when
963  * primary kernel is crashing.
964  */
965 static void __init reserve_crashkernel(void)
966 {
967 	unsigned long long crash_size, crash_base;
968 	unsigned long long total_mem;
969 	int ret;
970 
971 	total_mem = get_total_mem();
972 	ret = parse_crashkernel(boot_command_line, total_mem,
973 				&crash_size, &crash_base);
974 	if (ret)
975 		return;
976 
977 	if (crash_base <= 0) {
978 		unsigned long long crash_max = idmap_to_phys((u32)~0);
979 		crash_base = memblock_find_in_range(CRASH_ALIGN, crash_max,
980 						    crash_size, CRASH_ALIGN);
981 		if (!crash_base) {
982 			pr_err("crashkernel reservation failed - No suitable area found.\n");
983 			return;
984 		}
985 	} else {
986 		unsigned long long start;
987 
988 		start = memblock_find_in_range(crash_base,
989 					       crash_base + crash_size,
990 					       crash_size, SECTION_SIZE);
991 		if (start != crash_base) {
992 			pr_err("crashkernel reservation failed - memory is in use.\n");
993 			return;
994 		}
995 	}
996 
997 	ret = memblock_reserve(crash_base, crash_size);
998 	if (ret < 0) {
999 		pr_warn("crashkernel reservation failed - memory is in use (0x%lx)\n",
1000 			(unsigned long)crash_base);
1001 		return;
1002 	}
1003 
1004 	pr_info("Reserving %ldMB of memory at %ldMB for crashkernel (System RAM: %ldMB)\n",
1005 		(unsigned long)(crash_size >> 20),
1006 		(unsigned long)(crash_base >> 20),
1007 		(unsigned long)(total_mem >> 20));
1008 
1009 	crashk_res.start = crash_base;
1010 	crashk_res.end = crash_base + crash_size - 1;
1011 	insert_resource(&iomem_resource, &crashk_res);
1012 }
1013 #else
1014 static inline void reserve_crashkernel(void) {}
1015 #endif /* CONFIG_KEXEC */
1016 
1017 void __init hyp_mode_check(void)
1018 {
1019 #ifdef CONFIG_ARM_VIRT_EXT
1020 	sync_boot_mode();
1021 
1022 	if (is_hyp_mode_available()) {
1023 		pr_info("CPU: All CPU(s) started in HYP mode.\n");
1024 		pr_info("CPU: Virtualization extensions available.\n");
1025 	} else if (is_hyp_mode_mismatched()) {
1026 		pr_warn("CPU: WARNING: CPU(s) started in wrong/inconsistent modes (primary CPU mode 0x%x)\n",
1027 			__boot_cpu_mode & MODE_MASK);
1028 		pr_warn("CPU: This may indicate a broken bootloader or firmware.\n");
1029 	} else
1030 		pr_info("CPU: All CPU(s) started in SVC mode.\n");
1031 #endif
1032 }
1033 
1034 void __init setup_arch(char **cmdline_p)
1035 {
1036 	const struct machine_desc *mdesc;
1037 
1038 	setup_processor();
1039 	mdesc = setup_machine_fdt(__atags_pointer);
1040 	if (!mdesc)
1041 		mdesc = setup_machine_tags(__atags_pointer, __machine_arch_type);
1042 	machine_desc = mdesc;
1043 	machine_name = mdesc->name;
1044 	dump_stack_set_arch_desc("%s", mdesc->name);
1045 
1046 	if (mdesc->reboot_mode != REBOOT_HARD)
1047 		reboot_mode = mdesc->reboot_mode;
1048 
1049 	init_mm.start_code = (unsigned long) _text;
1050 	init_mm.end_code   = (unsigned long) _etext;
1051 	init_mm.end_data   = (unsigned long) _edata;
1052 	init_mm.brk	   = (unsigned long) _end;
1053 
1054 	/* populate cmd_line too for later use, preserving boot_command_line */
1055 	strlcpy(cmd_line, boot_command_line, COMMAND_LINE_SIZE);
1056 	*cmdline_p = cmd_line;
1057 
1058 	early_fixmap_init();
1059 	early_ioremap_init();
1060 
1061 	parse_early_param();
1062 
1063 #ifdef CONFIG_MMU
1064 	early_paging_init(mdesc);
1065 #endif
1066 	setup_dma_zone(mdesc);
1067 	efi_init();
1068 	sanity_check_meminfo();
1069 	arm_memblock_init(mdesc);
1070 
1071 	early_ioremap_reset();
1072 
1073 	paging_init(mdesc);
1074 	request_standard_resources(mdesc);
1075 
1076 	if (mdesc->restart)
1077 		arm_pm_restart = mdesc->restart;
1078 
1079 	unflatten_device_tree();
1080 
1081 	arm_dt_init_cpu_maps();
1082 	psci_dt_init();
1083 	xen_early_init();
1084 #ifdef CONFIG_SMP
1085 	if (is_smp()) {
1086 		if (!mdesc->smp_init || !mdesc->smp_init()) {
1087 			if (psci_smp_available())
1088 				smp_set_ops(&psci_smp_ops);
1089 			else if (mdesc->smp)
1090 				smp_set_ops(mdesc->smp);
1091 		}
1092 		smp_init_cpus();
1093 		smp_build_mpidr_hash();
1094 	}
1095 #endif
1096 
1097 	if (!is_smp())
1098 		hyp_mode_check();
1099 
1100 	reserve_crashkernel();
1101 
1102 #ifdef CONFIG_MULTI_IRQ_HANDLER
1103 	handle_arch_irq = mdesc->handle_irq;
1104 #endif
1105 
1106 #ifdef CONFIG_VT
1107 #if defined(CONFIG_VGA_CONSOLE)
1108 	conswitchp = &vga_con;
1109 #elif defined(CONFIG_DUMMY_CONSOLE)
1110 	conswitchp = &dummy_con;
1111 #endif
1112 #endif
1113 
1114 	if (mdesc->init_early)
1115 		mdesc->init_early();
1116 }
1117 
1118 
1119 static int __init topology_init(void)
1120 {
1121 	int cpu;
1122 
1123 	for_each_possible_cpu(cpu) {
1124 		struct cpuinfo_arm *cpuinfo = &per_cpu(cpu_data, cpu);
1125 		cpuinfo->cpu.hotpluggable = platform_can_hotplug_cpu(cpu);
1126 		register_cpu(&cpuinfo->cpu, cpu);
1127 	}
1128 
1129 	return 0;
1130 }
1131 subsys_initcall(topology_init);
1132 
1133 #ifdef CONFIG_HAVE_PROC_CPU
1134 static int __init proc_cpu_init(void)
1135 {
1136 	struct proc_dir_entry *res;
1137 
1138 	res = proc_mkdir("cpu", NULL);
1139 	if (!res)
1140 		return -ENOMEM;
1141 	return 0;
1142 }
1143 fs_initcall(proc_cpu_init);
1144 #endif
1145 
1146 static const char *hwcap_str[] = {
1147 	"swp",
1148 	"half",
1149 	"thumb",
1150 	"26bit",
1151 	"fastmult",
1152 	"fpa",
1153 	"vfp",
1154 	"edsp",
1155 	"java",
1156 	"iwmmxt",
1157 	"crunch",
1158 	"thumbee",
1159 	"neon",
1160 	"vfpv3",
1161 	"vfpv3d16",
1162 	"tls",
1163 	"vfpv4",
1164 	"idiva",
1165 	"idivt",
1166 	"vfpd32",
1167 	"lpae",
1168 	"evtstrm",
1169 	NULL
1170 };
1171 
1172 static const char *hwcap2_str[] = {
1173 	"aes",
1174 	"pmull",
1175 	"sha1",
1176 	"sha2",
1177 	"crc32",
1178 	NULL
1179 };
1180 
1181 static int c_show(struct seq_file *m, void *v)
1182 {
1183 	int i, j;
1184 	u32 cpuid;
1185 
1186 	for_each_online_cpu(i) {
1187 		/*
1188 		 * glibc reads /proc/cpuinfo to determine the number of
1189 		 * online processors, looking for lines beginning with
1190 		 * "processor".  Give glibc what it expects.
1191 		 */
1192 		seq_printf(m, "processor\t: %d\n", i);
1193 		cpuid = is_smp() ? per_cpu(cpu_data, i).cpuid : read_cpuid_id();
1194 		seq_printf(m, "model name\t: %s rev %d (%s)\n",
1195 			   cpu_name, cpuid & 15, elf_platform);
1196 
1197 #if defined(CONFIG_SMP)
1198 		seq_printf(m, "BogoMIPS\t: %lu.%02lu\n",
1199 			   per_cpu(cpu_data, i).loops_per_jiffy / (500000UL/HZ),
1200 			   (per_cpu(cpu_data, i).loops_per_jiffy / (5000UL/HZ)) % 100);
1201 #else
1202 		seq_printf(m, "BogoMIPS\t: %lu.%02lu\n",
1203 			   loops_per_jiffy / (500000/HZ),
1204 			   (loops_per_jiffy / (5000/HZ)) % 100);
1205 #endif
1206 		/* dump out the processor features */
1207 		seq_puts(m, "Features\t: ");
1208 
1209 		for (j = 0; hwcap_str[j]; j++)
1210 			if (elf_hwcap & (1 << j))
1211 				seq_printf(m, "%s ", hwcap_str[j]);
1212 
1213 		for (j = 0; hwcap2_str[j]; j++)
1214 			if (elf_hwcap2 & (1 << j))
1215 				seq_printf(m, "%s ", hwcap2_str[j]);
1216 
1217 		seq_printf(m, "\nCPU implementer\t: 0x%02x\n", cpuid >> 24);
1218 		seq_printf(m, "CPU architecture: %s\n",
1219 			   proc_arch[cpu_architecture()]);
1220 
1221 		if ((cpuid & 0x0008f000) == 0x00000000) {
1222 			/* pre-ARM7 */
1223 			seq_printf(m, "CPU part\t: %07x\n", cpuid >> 4);
1224 		} else {
1225 			if ((cpuid & 0x0008f000) == 0x00007000) {
1226 				/* ARM7 */
1227 				seq_printf(m, "CPU variant\t: 0x%02x\n",
1228 					   (cpuid >> 16) & 127);
1229 			} else {
1230 				/* post-ARM7 */
1231 				seq_printf(m, "CPU variant\t: 0x%x\n",
1232 					   (cpuid >> 20) & 15);
1233 			}
1234 			seq_printf(m, "CPU part\t: 0x%03x\n",
1235 				   (cpuid >> 4) & 0xfff);
1236 		}
1237 		seq_printf(m, "CPU revision\t: %d\n\n", cpuid & 15);
1238 	}
1239 
1240 	seq_printf(m, "Hardware\t: %s\n", machine_name);
1241 	seq_printf(m, "Revision\t: %04x\n", system_rev);
1242 	seq_printf(m, "Serial\t\t: %s\n", system_serial);
1243 
1244 	return 0;
1245 }
1246 
1247 static void *c_start(struct seq_file *m, loff_t *pos)
1248 {
1249 	return *pos < 1 ? (void *)1 : NULL;
1250 }
1251 
1252 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
1253 {
1254 	++*pos;
1255 	return NULL;
1256 }
1257 
1258 static void c_stop(struct seq_file *m, void *v)
1259 {
1260 }
1261 
1262 const struct seq_operations cpuinfo_op = {
1263 	.start	= c_start,
1264 	.next	= c_next,
1265 	.stop	= c_stop,
1266 	.show	= c_show
1267 };
1268