1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Common boot and setup code for both 32-bit and 64-bit.
4  * Extracted from arch/powerpc/kernel/setup_64.c.
5  *
6  * Copyright (C) 2001 PPC64 Team, IBM Corp
7  */
8 
9 #undef DEBUG
10 
11 #include <linux/export.h>
12 #include <linux/string.h>
13 #include <linux/sched.h>
14 #include <linux/init.h>
15 #include <linux/kernel.h>
16 #include <linux/reboot.h>
17 #include <linux/delay.h>
18 #include <linux/initrd.h>
19 #include <linux/platform_device.h>
20 #include <linux/seq_file.h>
21 #include <linux/ioport.h>
22 #include <linux/console.h>
23 #include <linux/screen_info.h>
24 #include <linux/root_dev.h>
25 #include <linux/notifier.h>
26 #include <linux/cpu.h>
27 #include <linux/unistd.h>
28 #include <linux/serial.h>
29 #include <linux/serial_8250.h>
30 #include <linux/percpu.h>
31 #include <linux/memblock.h>
32 #include <linux/of_platform.h>
33 #include <linux/hugetlb.h>
34 #include <asm/debugfs.h>
35 #include <asm/io.h>
36 #include <asm/paca.h>
37 #include <asm/prom.h>
38 #include <asm/processor.h>
39 #include <asm/vdso_datapage.h>
40 #include <asm/pgtable.h>
41 #include <asm/smp.h>
42 #include <asm/elf.h>
43 #include <asm/machdep.h>
44 #include <asm/time.h>
45 #include <asm/cputable.h>
46 #include <asm/sections.h>
47 #include <asm/firmware.h>
48 #include <asm/btext.h>
49 #include <asm/nvram.h>
50 #include <asm/setup.h>
51 #include <asm/rtas.h>
52 #include <asm/iommu.h>
53 #include <asm/serial.h>
54 #include <asm/cache.h>
55 #include <asm/page.h>
56 #include <asm/mmu.h>
57 #include <asm/xmon.h>
58 #include <asm/cputhreads.h>
59 #include <mm/mmu_decl.h>
60 #include <asm/fadump.h>
61 #include <asm/udbg.h>
62 #include <asm/hugetlb.h>
63 #include <asm/livepatch.h>
64 #include <asm/mmu_context.h>
65 #include <asm/cpu_has_feature.h>
66 #include <asm/kasan.h>
67 
68 #include "setup.h"
69 
70 #ifdef DEBUG
71 #include <asm/udbg.h>
72 #define DBG(fmt...) udbg_printf(fmt)
73 #else
74 #define DBG(fmt...)
75 #endif
76 
77 /* The main machine-dep calls structure
78  */
79 struct machdep_calls ppc_md;
80 EXPORT_SYMBOL(ppc_md);
81 struct machdep_calls *machine_id;
82 EXPORT_SYMBOL(machine_id);
83 
84 int boot_cpuid = -1;
85 EXPORT_SYMBOL_GPL(boot_cpuid);
86 
87 /*
88  * These are used in binfmt_elf.c to put aux entries on the stack
89  * for each elf executable being started.
90  */
91 int dcache_bsize;
92 int icache_bsize;
93 int ucache_bsize;
94 
95 
96 unsigned long klimit = (unsigned long) _end;
97 
98 /*
99  * This still seems to be needed... -- paulus
100  */
101 struct screen_info screen_info = {
102 	.orig_x = 0,
103 	.orig_y = 25,
104 	.orig_video_cols = 80,
105 	.orig_video_lines = 25,
106 	.orig_video_isVGA = 1,
107 	.orig_video_points = 16
108 };
109 #if defined(CONFIG_FB_VGA16_MODULE)
110 EXPORT_SYMBOL(screen_info);
111 #endif
112 
113 /* Variables required to store legacy IO irq routing */
114 int of_i8042_kbd_irq;
115 EXPORT_SYMBOL_GPL(of_i8042_kbd_irq);
116 int of_i8042_aux_irq;
117 EXPORT_SYMBOL_GPL(of_i8042_aux_irq);
118 
119 #ifdef __DO_IRQ_CANON
120 /* XXX should go elsewhere eventually */
121 int ppc_do_canonicalize_irqs;
122 EXPORT_SYMBOL(ppc_do_canonicalize_irqs);
123 #endif
124 
125 #ifdef CONFIG_CRASH_CORE
126 /* This keeps a track of which one is the crashing cpu. */
127 int crashing_cpu = -1;
128 #endif
129 
130 /* also used by kexec */
131 void machine_shutdown(void)
132 {
133 	/*
134 	 * if fadump is active, cleanup the fadump registration before we
135 	 * shutdown.
136 	 */
137 	fadump_cleanup();
138 
139 	if (ppc_md.machine_shutdown)
140 		ppc_md.machine_shutdown();
141 }
142 
143 static void machine_hang(void)
144 {
145 	pr_emerg("System Halted, OK to turn off power\n");
146 	local_irq_disable();
147 	while (1)
148 		;
149 }
150 
151 void machine_restart(char *cmd)
152 {
153 	machine_shutdown();
154 	if (ppc_md.restart)
155 		ppc_md.restart(cmd);
156 
157 	smp_send_stop();
158 
159 	do_kernel_restart(cmd);
160 	mdelay(1000);
161 
162 	machine_hang();
163 }
164 
165 void machine_power_off(void)
166 {
167 	machine_shutdown();
168 	if (pm_power_off)
169 		pm_power_off();
170 
171 	smp_send_stop();
172 	machine_hang();
173 }
174 /* Used by the G5 thermal driver */
175 EXPORT_SYMBOL_GPL(machine_power_off);
176 
177 void (*pm_power_off)(void);
178 EXPORT_SYMBOL_GPL(pm_power_off);
179 
180 void machine_halt(void)
181 {
182 	machine_shutdown();
183 	if (ppc_md.halt)
184 		ppc_md.halt();
185 
186 	smp_send_stop();
187 	machine_hang();
188 }
189 
190 #ifdef CONFIG_SMP
191 DEFINE_PER_CPU(unsigned int, cpu_pvr);
192 #endif
193 
194 static void show_cpuinfo_summary(struct seq_file *m)
195 {
196 	struct device_node *root;
197 	const char *model = NULL;
198 	unsigned long bogosum = 0;
199 	int i;
200 
201 	if (IS_ENABLED(CONFIG_SMP) && IS_ENABLED(CONFIG_PPC32)) {
202 		for_each_online_cpu(i)
203 			bogosum += loops_per_jiffy;
204 		seq_printf(m, "total bogomips\t: %lu.%02lu\n",
205 			   bogosum / (500000 / HZ), bogosum / (5000 / HZ) % 100);
206 	}
207 	seq_printf(m, "timebase\t: %lu\n", ppc_tb_freq);
208 	if (ppc_md.name)
209 		seq_printf(m, "platform\t: %s\n", ppc_md.name);
210 	root = of_find_node_by_path("/");
211 	if (root)
212 		model = of_get_property(root, "model", NULL);
213 	if (model)
214 		seq_printf(m, "model\t\t: %s\n", model);
215 	of_node_put(root);
216 
217 	if (ppc_md.show_cpuinfo != NULL)
218 		ppc_md.show_cpuinfo(m);
219 
220 	/* Display the amount of memory */
221 	if (IS_ENABLED(CONFIG_PPC32))
222 		seq_printf(m, "Memory\t\t: %d MB\n",
223 			   (unsigned int)(total_memory / (1024 * 1024)));
224 }
225 
226 static int show_cpuinfo(struct seq_file *m, void *v)
227 {
228 	unsigned long cpu_id = (unsigned long)v - 1;
229 	unsigned int pvr;
230 	unsigned long proc_freq;
231 	unsigned short maj;
232 	unsigned short min;
233 
234 #ifdef CONFIG_SMP
235 	pvr = per_cpu(cpu_pvr, cpu_id);
236 #else
237 	pvr = mfspr(SPRN_PVR);
238 #endif
239 	maj = (pvr >> 8) & 0xFF;
240 	min = pvr & 0xFF;
241 
242 	seq_printf(m, "processor\t: %lu\n", cpu_id);
243 	seq_printf(m, "cpu\t\t: ");
244 
245 	if (cur_cpu_spec->pvr_mask && cur_cpu_spec->cpu_name)
246 		seq_printf(m, "%s", cur_cpu_spec->cpu_name);
247 	else
248 		seq_printf(m, "unknown (%08x)", pvr);
249 
250 	if (cpu_has_feature(CPU_FTR_ALTIVEC))
251 		seq_printf(m, ", altivec supported");
252 
253 	seq_printf(m, "\n");
254 
255 #ifdef CONFIG_TAU
256 	if (cpu_has_feature(CPU_FTR_TAU)) {
257 		if (IS_ENABLED(CONFIG_TAU_AVERAGE)) {
258 			/* more straightforward, but potentially misleading */
259 			seq_printf(m,  "temperature \t: %u C (uncalibrated)\n",
260 				   cpu_temp(cpu_id));
261 		} else {
262 			/* show the actual temp sensor range */
263 			u32 temp;
264 			temp = cpu_temp_both(cpu_id);
265 			seq_printf(m, "temperature \t: %u-%u C (uncalibrated)\n",
266 				   temp & 0xff, temp >> 16);
267 		}
268 	}
269 #endif /* CONFIG_TAU */
270 
271 	/*
272 	 * Platforms that have variable clock rates, should implement
273 	 * the method ppc_md.get_proc_freq() that reports the clock
274 	 * rate of a given cpu. The rest can use ppc_proc_freq to
275 	 * report the clock rate that is same across all cpus.
276 	 */
277 	if (ppc_md.get_proc_freq)
278 		proc_freq = ppc_md.get_proc_freq(cpu_id);
279 	else
280 		proc_freq = ppc_proc_freq;
281 
282 	if (proc_freq)
283 		seq_printf(m, "clock\t\t: %lu.%06luMHz\n",
284 			   proc_freq / 1000000, proc_freq % 1000000);
285 
286 	if (ppc_md.show_percpuinfo != NULL)
287 		ppc_md.show_percpuinfo(m, cpu_id);
288 
289 	/* If we are a Freescale core do a simple check so
290 	 * we dont have to keep adding cases in the future */
291 	if (PVR_VER(pvr) & 0x8000) {
292 		switch (PVR_VER(pvr)) {
293 		case 0x8000:	/* 7441/7450/7451, Voyager */
294 		case 0x8001:	/* 7445/7455, Apollo 6 */
295 		case 0x8002:	/* 7447/7457, Apollo 7 */
296 		case 0x8003:	/* 7447A, Apollo 7 PM */
297 		case 0x8004:	/* 7448, Apollo 8 */
298 		case 0x800c:	/* 7410, Nitro */
299 			maj = ((pvr >> 8) & 0xF);
300 			min = PVR_MIN(pvr);
301 			break;
302 		default:	/* e500/book-e */
303 			maj = PVR_MAJ(pvr);
304 			min = PVR_MIN(pvr);
305 			break;
306 		}
307 	} else {
308 		switch (PVR_VER(pvr)) {
309 			case 0x0020:	/* 403 family */
310 				maj = PVR_MAJ(pvr) + 1;
311 				min = PVR_MIN(pvr);
312 				break;
313 			case 0x1008:	/* 740P/750P ?? */
314 				maj = ((pvr >> 8) & 0xFF) - 1;
315 				min = pvr & 0xFF;
316 				break;
317 			case 0x004e: /* POWER9 bits 12-15 give chip type */
318 				maj = (pvr >> 8) & 0x0F;
319 				min = pvr & 0xFF;
320 				break;
321 			default:
322 				maj = (pvr >> 8) & 0xFF;
323 				min = pvr & 0xFF;
324 				break;
325 		}
326 	}
327 
328 	seq_printf(m, "revision\t: %hd.%hd (pvr %04x %04x)\n",
329 		   maj, min, PVR_VER(pvr), PVR_REV(pvr));
330 
331 	if (IS_ENABLED(CONFIG_PPC32))
332 		seq_printf(m, "bogomips\t: %lu.%02lu\n", loops_per_jiffy / (500000 / HZ),
333 			   (loops_per_jiffy / (5000 / HZ)) % 100);
334 
335 	seq_printf(m, "\n");
336 
337 	/* If this is the last cpu, print the summary */
338 	if (cpumask_next(cpu_id, cpu_online_mask) >= nr_cpu_ids)
339 		show_cpuinfo_summary(m);
340 
341 	return 0;
342 }
343 
344 static void *c_start(struct seq_file *m, loff_t *pos)
345 {
346 	if (*pos == 0)	/* just in case, cpu 0 is not the first */
347 		*pos = cpumask_first(cpu_online_mask);
348 	else
349 		*pos = cpumask_next(*pos - 1, cpu_online_mask);
350 	if ((*pos) < nr_cpu_ids)
351 		return (void *)(unsigned long)(*pos + 1);
352 	return NULL;
353 }
354 
355 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
356 {
357 	(*pos)++;
358 	return c_start(m, pos);
359 }
360 
361 static void c_stop(struct seq_file *m, void *v)
362 {
363 }
364 
365 const struct seq_operations cpuinfo_op = {
366 	.start	= c_start,
367 	.next	= c_next,
368 	.stop	= c_stop,
369 	.show	= show_cpuinfo,
370 };
371 
372 void __init check_for_initrd(void)
373 {
374 #ifdef CONFIG_BLK_DEV_INITRD
375 	DBG(" -> check_for_initrd()  initrd_start=0x%lx  initrd_end=0x%lx\n",
376 	    initrd_start, initrd_end);
377 
378 	/* If we were passed an initrd, set the ROOT_DEV properly if the values
379 	 * look sensible. If not, clear initrd reference.
380 	 */
381 	if (is_kernel_addr(initrd_start) && is_kernel_addr(initrd_end) &&
382 	    initrd_end > initrd_start)
383 		ROOT_DEV = Root_RAM0;
384 	else
385 		initrd_start = initrd_end = 0;
386 
387 	if (initrd_start)
388 		pr_info("Found initrd at 0x%lx:0x%lx\n", initrd_start, initrd_end);
389 
390 	DBG(" <- check_for_initrd()\n");
391 #endif /* CONFIG_BLK_DEV_INITRD */
392 }
393 
394 #ifdef CONFIG_SMP
395 
396 int threads_per_core, threads_per_subcore, threads_shift __read_mostly;
397 cpumask_t threads_core_mask __read_mostly;
398 EXPORT_SYMBOL_GPL(threads_per_core);
399 EXPORT_SYMBOL_GPL(threads_per_subcore);
400 EXPORT_SYMBOL_GPL(threads_shift);
401 EXPORT_SYMBOL_GPL(threads_core_mask);
402 
403 static void __init cpu_init_thread_core_maps(int tpc)
404 {
405 	int i;
406 
407 	threads_per_core = tpc;
408 	threads_per_subcore = tpc;
409 	cpumask_clear(&threads_core_mask);
410 
411 	/* This implementation only supports power of 2 number of threads
412 	 * for simplicity and performance
413 	 */
414 	threads_shift = ilog2(tpc);
415 	BUG_ON(tpc != (1 << threads_shift));
416 
417 	for (i = 0; i < tpc; i++)
418 		cpumask_set_cpu(i, &threads_core_mask);
419 
420 	printk(KERN_INFO "CPU maps initialized for %d thread%s per core\n",
421 	       tpc, tpc > 1 ? "s" : "");
422 	printk(KERN_DEBUG " (thread shift is %d)\n", threads_shift);
423 }
424 
425 
426 u32 *cpu_to_phys_id = NULL;
427 
428 /**
429  * setup_cpu_maps - initialize the following cpu maps:
430  *                  cpu_possible_mask
431  *                  cpu_present_mask
432  *
433  * Having the possible map set up early allows us to restrict allocations
434  * of things like irqstacks to nr_cpu_ids rather than NR_CPUS.
435  *
436  * We do not initialize the online map here; cpus set their own bits in
437  * cpu_online_mask as they come up.
438  *
439  * This function is valid only for Open Firmware systems.  finish_device_tree
440  * must be called before using this.
441  *
442  * While we're here, we may as well set the "physical" cpu ids in the paca.
443  *
444  * NOTE: This must match the parsing done in early_init_dt_scan_cpus.
445  */
446 void __init smp_setup_cpu_maps(void)
447 {
448 	struct device_node *dn;
449 	int cpu = 0;
450 	int nthreads = 1;
451 
452 	DBG("smp_setup_cpu_maps()\n");
453 
454 	cpu_to_phys_id = memblock_alloc(nr_cpu_ids * sizeof(u32),
455 					__alignof__(u32));
456 	if (!cpu_to_phys_id)
457 		panic("%s: Failed to allocate %zu bytes align=0x%zx\n",
458 		      __func__, nr_cpu_ids * sizeof(u32), __alignof__(u32));
459 
460 	for_each_node_by_type(dn, "cpu") {
461 		const __be32 *intserv;
462 		__be32 cpu_be;
463 		int j, len;
464 
465 		DBG("  * %pOF...\n", dn);
466 
467 		intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s",
468 				&len);
469 		if (intserv) {
470 			DBG("    ibm,ppc-interrupt-server#s -> %d threads\n",
471 			    nthreads);
472 		} else {
473 			DBG("    no ibm,ppc-interrupt-server#s -> 1 thread\n");
474 			intserv = of_get_property(dn, "reg", &len);
475 			if (!intserv) {
476 				cpu_be = cpu_to_be32(cpu);
477 				/* XXX: what is this? uninitialized?? */
478 				intserv = &cpu_be;	/* assume logical == phys */
479 				len = 4;
480 			}
481 		}
482 
483 		nthreads = len / sizeof(int);
484 
485 		for (j = 0; j < nthreads && cpu < nr_cpu_ids; j++) {
486 			bool avail;
487 
488 			DBG("    thread %d -> cpu %d (hard id %d)\n",
489 			    j, cpu, be32_to_cpu(intserv[j]));
490 
491 			avail = of_device_is_available(dn);
492 			if (!avail)
493 				avail = !of_property_match_string(dn,
494 						"enable-method", "spin-table");
495 
496 			set_cpu_present(cpu, avail);
497 			set_cpu_possible(cpu, true);
498 			cpu_to_phys_id[cpu] = be32_to_cpu(intserv[j]);
499 			cpu++;
500 		}
501 
502 		if (cpu >= nr_cpu_ids) {
503 			of_node_put(dn);
504 			break;
505 		}
506 	}
507 
508 	/* If no SMT supported, nthreads is forced to 1 */
509 	if (!cpu_has_feature(CPU_FTR_SMT)) {
510 		DBG("  SMT disabled ! nthreads forced to 1\n");
511 		nthreads = 1;
512 	}
513 
514 #ifdef CONFIG_PPC64
515 	/*
516 	 * On pSeries LPAR, we need to know how many cpus
517 	 * could possibly be added to this partition.
518 	 */
519 	if (firmware_has_feature(FW_FEATURE_LPAR) &&
520 	    (dn = of_find_node_by_path("/rtas"))) {
521 		int num_addr_cell, num_size_cell, maxcpus;
522 		const __be32 *ireg;
523 
524 		num_addr_cell = of_n_addr_cells(dn);
525 		num_size_cell = of_n_size_cells(dn);
526 
527 		ireg = of_get_property(dn, "ibm,lrdr-capacity", NULL);
528 
529 		if (!ireg)
530 			goto out;
531 
532 		maxcpus = be32_to_cpup(ireg + num_addr_cell + num_size_cell);
533 
534 		/* Double maxcpus for processors which have SMT capability */
535 		if (cpu_has_feature(CPU_FTR_SMT))
536 			maxcpus *= nthreads;
537 
538 		if (maxcpus > nr_cpu_ids) {
539 			printk(KERN_WARNING
540 			       "Partition configured for %d cpus, "
541 			       "operating system maximum is %u.\n",
542 			       maxcpus, nr_cpu_ids);
543 			maxcpus = nr_cpu_ids;
544 		} else
545 			printk(KERN_INFO "Partition configured for %d cpus.\n",
546 			       maxcpus);
547 
548 		for (cpu = 0; cpu < maxcpus; cpu++)
549 			set_cpu_possible(cpu, true);
550 	out:
551 		of_node_put(dn);
552 	}
553 	vdso_data->processorCount = num_present_cpus();
554 #endif /* CONFIG_PPC64 */
555 
556         /* Initialize CPU <=> thread mapping/
557 	 *
558 	 * WARNING: We assume that the number of threads is the same for
559 	 * every CPU in the system. If that is not the case, then some code
560 	 * here will have to be reworked
561 	 */
562 	cpu_init_thread_core_maps(nthreads);
563 
564 	/* Now that possible cpus are set, set nr_cpu_ids for later use */
565 	setup_nr_cpu_ids();
566 
567 	free_unused_pacas();
568 }
569 #endif /* CONFIG_SMP */
570 
571 #ifdef CONFIG_PCSPKR_PLATFORM
572 static __init int add_pcspkr(void)
573 {
574 	struct device_node *np;
575 	struct platform_device *pd;
576 	int ret;
577 
578 	np = of_find_compatible_node(NULL, NULL, "pnpPNP,100");
579 	of_node_put(np);
580 	if (!np)
581 		return -ENODEV;
582 
583 	pd = platform_device_alloc("pcspkr", -1);
584 	if (!pd)
585 		return -ENOMEM;
586 
587 	ret = platform_device_add(pd);
588 	if (ret)
589 		platform_device_put(pd);
590 
591 	return ret;
592 }
593 device_initcall(add_pcspkr);
594 #endif	/* CONFIG_PCSPKR_PLATFORM */
595 
596 void probe_machine(void)
597 {
598 	extern struct machdep_calls __machine_desc_start;
599 	extern struct machdep_calls __machine_desc_end;
600 	unsigned int i;
601 
602 	/*
603 	 * Iterate all ppc_md structures until we find the proper
604 	 * one for the current machine type
605 	 */
606 	DBG("Probing machine type ...\n");
607 
608 	/*
609 	 * Check ppc_md is empty, if not we have a bug, ie, we setup an
610 	 * entry before probe_machine() which will be overwritten
611 	 */
612 	for (i = 0; i < (sizeof(ppc_md) / sizeof(void *)); i++) {
613 		if (((void **)&ppc_md)[i]) {
614 			printk(KERN_ERR "Entry %d in ppc_md non empty before"
615 			       " machine probe !\n", i);
616 		}
617 	}
618 
619 	for (machine_id = &__machine_desc_start;
620 	     machine_id < &__machine_desc_end;
621 	     machine_id++) {
622 		DBG("  %s ...", machine_id->name);
623 		memcpy(&ppc_md, machine_id, sizeof(struct machdep_calls));
624 		if (ppc_md.probe()) {
625 			DBG(" match !\n");
626 			break;
627 		}
628 		DBG("\n");
629 	}
630 	/* What can we do if we didn't find ? */
631 	if (machine_id >= &__machine_desc_end) {
632 		pr_err("No suitable machine description found !\n");
633 		for (;;);
634 	}
635 
636 	printk(KERN_INFO "Using %s machine description\n", ppc_md.name);
637 }
638 
639 /* Match a class of boards, not a specific device configuration. */
640 int check_legacy_ioport(unsigned long base_port)
641 {
642 	struct device_node *parent, *np = NULL;
643 	int ret = -ENODEV;
644 
645 	switch(base_port) {
646 	case I8042_DATA_REG:
647 		if (!(np = of_find_compatible_node(NULL, NULL, "pnpPNP,303")))
648 			np = of_find_compatible_node(NULL, NULL, "pnpPNP,f03");
649 		if (np) {
650 			parent = of_get_parent(np);
651 
652 			of_i8042_kbd_irq = irq_of_parse_and_map(parent, 0);
653 			if (!of_i8042_kbd_irq)
654 				of_i8042_kbd_irq = 1;
655 
656 			of_i8042_aux_irq = irq_of_parse_and_map(parent, 1);
657 			if (!of_i8042_aux_irq)
658 				of_i8042_aux_irq = 12;
659 
660 			of_node_put(np);
661 			np = parent;
662 			break;
663 		}
664 		np = of_find_node_by_type(NULL, "8042");
665 		/* Pegasos has no device_type on its 8042 node, look for the
666 		 * name instead */
667 		if (!np)
668 			np = of_find_node_by_name(NULL, "8042");
669 		if (np) {
670 			of_i8042_kbd_irq = 1;
671 			of_i8042_aux_irq = 12;
672 		}
673 		break;
674 	case FDC_BASE: /* FDC1 */
675 		np = of_find_node_by_type(NULL, "fdc");
676 		break;
677 	default:
678 		/* ipmi is supposed to fail here */
679 		break;
680 	}
681 	if (!np)
682 		return ret;
683 	parent = of_get_parent(np);
684 	if (parent) {
685 		if (of_node_is_type(parent, "isa"))
686 			ret = 0;
687 		of_node_put(parent);
688 	}
689 	of_node_put(np);
690 	return ret;
691 }
692 EXPORT_SYMBOL(check_legacy_ioport);
693 
694 static int ppc_panic_event(struct notifier_block *this,
695                              unsigned long event, void *ptr)
696 {
697 	/*
698 	 * panic does a local_irq_disable, but we really
699 	 * want interrupts to be hard disabled.
700 	 */
701 	hard_irq_disable();
702 
703 	/*
704 	 * If firmware-assisted dump has been registered then trigger
705 	 * firmware-assisted dump and let firmware handle everything else.
706 	 */
707 	crash_fadump(NULL, ptr);
708 	if (ppc_md.panic)
709 		ppc_md.panic(ptr);  /* May not return */
710 	return NOTIFY_DONE;
711 }
712 
713 static struct notifier_block ppc_panic_block = {
714 	.notifier_call = ppc_panic_event,
715 	.priority = INT_MIN /* may not return; must be done last */
716 };
717 
718 /*
719  * Dump out kernel offset information on panic.
720  */
721 static int dump_kernel_offset(struct notifier_block *self, unsigned long v,
722 			      void *p)
723 {
724 	pr_emerg("Kernel Offset: 0x%lx from 0x%lx\n",
725 		 kaslr_offset(), KERNELBASE);
726 
727 	return 0;
728 }
729 
730 static struct notifier_block kernel_offset_notifier = {
731 	.notifier_call = dump_kernel_offset
732 };
733 
734 void __init setup_panic(void)
735 {
736 	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && kaslr_offset() > 0)
737 		atomic_notifier_chain_register(&panic_notifier_list,
738 					       &kernel_offset_notifier);
739 
740 	/* PPC64 always does a hard irq disable in its panic handler */
741 	if (!IS_ENABLED(CONFIG_PPC64) && !ppc_md.panic)
742 		return;
743 	atomic_notifier_chain_register(&panic_notifier_list, &ppc_panic_block);
744 }
745 
746 #ifdef CONFIG_CHECK_CACHE_COHERENCY
747 /*
748  * For platforms that have configurable cache-coherency.  This function
749  * checks that the cache coherency setting of the kernel matches the setting
750  * left by the firmware, as indicated in the device tree.  Since a mismatch
751  * will eventually result in DMA failures, we print * and error and call
752  * BUG() in that case.
753  */
754 
755 #define KERNEL_COHERENCY	(!IS_ENABLED(CONFIG_NOT_COHERENT_CACHE))
756 
757 static int __init check_cache_coherency(void)
758 {
759 	struct device_node *np;
760 	const void *prop;
761 	bool devtree_coherency;
762 
763 	np = of_find_node_by_path("/");
764 	prop = of_get_property(np, "coherency-off", NULL);
765 	of_node_put(np);
766 
767 	devtree_coherency = prop ? false : true;
768 
769 	if (devtree_coherency != KERNEL_COHERENCY) {
770 		printk(KERN_ERR
771 			"kernel coherency:%s != device tree_coherency:%s\n",
772 			KERNEL_COHERENCY ? "on" : "off",
773 			devtree_coherency ? "on" : "off");
774 		BUG();
775 	}
776 
777 	return 0;
778 }
779 
780 late_initcall(check_cache_coherency);
781 #endif /* CONFIG_CHECK_CACHE_COHERENCY */
782 
783 #ifdef CONFIG_DEBUG_FS
784 struct dentry *powerpc_debugfs_root;
785 EXPORT_SYMBOL(powerpc_debugfs_root);
786 
787 static int powerpc_debugfs_init(void)
788 {
789 	powerpc_debugfs_root = debugfs_create_dir("powerpc", NULL);
790 	return 0;
791 }
792 arch_initcall(powerpc_debugfs_init);
793 #endif
794 
795 void ppc_printk_progress(char *s, unsigned short hex)
796 {
797 	pr_info("%s\n", s);
798 }
799 
800 static __init void print_system_info(void)
801 {
802 	pr_info("-----------------------------------------------------\n");
803 	pr_info("phys_mem_size     = 0x%llx\n",
804 		(unsigned long long)memblock_phys_mem_size());
805 
806 	pr_info("dcache_bsize      = 0x%x\n", dcache_bsize);
807 	pr_info("icache_bsize      = 0x%x\n", icache_bsize);
808 	if (ucache_bsize != 0)
809 		pr_info("ucache_bsize      = 0x%x\n", ucache_bsize);
810 
811 	pr_info("cpu_features      = 0x%016lx\n", cur_cpu_spec->cpu_features);
812 	pr_info("  possible        = 0x%016lx\n",
813 		(unsigned long)CPU_FTRS_POSSIBLE);
814 	pr_info("  always          = 0x%016lx\n",
815 		(unsigned long)CPU_FTRS_ALWAYS);
816 	pr_info("cpu_user_features = 0x%08x 0x%08x\n",
817 		cur_cpu_spec->cpu_user_features,
818 		cur_cpu_spec->cpu_user_features2);
819 	pr_info("mmu_features      = 0x%08x\n", cur_cpu_spec->mmu_features);
820 #ifdef CONFIG_PPC64
821 	pr_info("firmware_features = 0x%016lx\n", powerpc_firmware_features);
822 #ifdef CONFIG_PPC_BOOK3S
823 	pr_info("vmalloc start     = 0x%lx\n", KERN_VIRT_START);
824 	pr_info("IO start          = 0x%lx\n", KERN_IO_START);
825 	pr_info("vmemmap start     = 0x%lx\n", (unsigned long)vmemmap);
826 #endif
827 #endif
828 
829 	if (!early_radix_enabled())
830 		print_system_hash_info();
831 
832 	if (PHYSICAL_START > 0)
833 		pr_info("physical_start    = 0x%llx\n",
834 		       (unsigned long long)PHYSICAL_START);
835 	pr_info("-----------------------------------------------------\n");
836 }
837 
838 #ifdef CONFIG_SMP
839 static void smp_setup_pacas(void)
840 {
841 	int cpu;
842 
843 	for_each_possible_cpu(cpu) {
844 		if (cpu == smp_processor_id())
845 			continue;
846 		allocate_paca(cpu);
847 		set_hard_smp_processor_id(cpu, cpu_to_phys_id[cpu]);
848 	}
849 
850 	memblock_free(__pa(cpu_to_phys_id), nr_cpu_ids * sizeof(u32));
851 	cpu_to_phys_id = NULL;
852 }
853 #endif
854 
855 /*
856  * Called into from start_kernel this initializes memblock, which is used
857  * to manage page allocation until mem_init is called.
858  */
859 void __init setup_arch(char **cmdline_p)
860 {
861 	kasan_init();
862 
863 	*cmdline_p = boot_command_line;
864 
865 	/* Set a half-reasonable default so udelay does something sensible */
866 	loops_per_jiffy = 500000000 / HZ;
867 
868 	/* Unflatten the device-tree passed by prom_init or kexec */
869 	unflatten_device_tree();
870 
871 	/*
872 	 * Initialize cache line/block info from device-tree (on ppc64) or
873 	 * just cputable (on ppc32).
874 	 */
875 	initialize_cache_info();
876 
877 	/* Initialize RTAS if available. */
878 	rtas_initialize();
879 
880 	/* Check if we have an initrd provided via the device-tree. */
881 	check_for_initrd();
882 
883 	/* Probe the machine type, establish ppc_md. */
884 	probe_machine();
885 
886 	/* Setup panic notifier if requested by the platform. */
887 	setup_panic();
888 
889 	/*
890 	 * Configure ppc_md.power_save (ppc32 only, 64-bit machines do
891 	 * it from their respective probe() function.
892 	 */
893 	setup_power_save();
894 
895 	/* Discover standard serial ports. */
896 	find_legacy_serial_ports();
897 
898 	/* Register early console with the printk subsystem. */
899 	register_early_udbg_console();
900 
901 	/* Setup the various CPU maps based on the device-tree. */
902 	smp_setup_cpu_maps();
903 
904 	/* Initialize xmon. */
905 	xmon_setup();
906 
907 	/* Check the SMT related command line arguments (ppc64). */
908 	check_smt_enabled();
909 
910 	/* Parse memory topology */
911 	mem_topology_setup();
912 
913 	/*
914 	 * Release secondary cpus out of their spinloops at 0x60 now that
915 	 * we can map physical -> logical CPU ids.
916 	 *
917 	 * Freescale Book3e parts spin in a loop provided by firmware,
918 	 * so smp_release_cpus() does nothing for them.
919 	 */
920 #ifdef CONFIG_SMP
921 	smp_setup_pacas();
922 
923 	/* On BookE, setup per-core TLB data structures. */
924 	setup_tlb_core_data();
925 
926 	smp_release_cpus();
927 #endif
928 
929 	/* Print various info about the machine that has been gathered so far. */
930 	print_system_info();
931 
932 	/* Reserve large chunks of memory for use by CMA for KVM. */
933 	kvm_cma_reserve();
934 
935 	klp_init_thread_info(&init_task);
936 
937 	init_mm.start_code = (unsigned long)_stext;
938 	init_mm.end_code = (unsigned long) _etext;
939 	init_mm.end_data = (unsigned long) _edata;
940 	init_mm.brk = klimit;
941 
942 	mm_iommu_init(&init_mm);
943 	irqstack_early_init();
944 	exc_lvl_early_init();
945 	emergency_stack_init();
946 
947 	initmem_init();
948 
949 	early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT);
950 
951 	if (ppc_md.setup_arch)
952 		ppc_md.setup_arch();
953 
954 	setup_barrier_nospec();
955 	setup_spectre_v2();
956 
957 	paging_init();
958 
959 	/* Initialize the MMU context management stuff. */
960 	mmu_context_init();
961 
962 	/* Interrupt code needs to be 64K-aligned. */
963 	if (IS_ENABLED(CONFIG_PPC64) && (unsigned long)_stext & 0xffff)
964 		panic("Kernelbase not 64K-aligned (0x%lx)!\n",
965 		      (unsigned long)_stext);
966 }
967