1 /*
2  * Common boot and setup code for both 32-bit and 64-bit.
3  * Extracted from arch/powerpc/kernel/setup_64.c.
4  *
5  * Copyright (C) 2001 PPC64 Team, IBM Corp
6  *
7  *      This program is free software; you can redistribute it and/or
8  *      modify it under the terms of the GNU General Public License
9  *      as published by the Free Software Foundation; either version
10  *      2 of the License, or (at your option) any later version.
11  */
12 
13 #undef DEBUG
14 
15 #include <linux/export.h>
16 #include <linux/string.h>
17 #include <linux/sched.h>
18 #include <linux/init.h>
19 #include <linux/kernel.h>
20 #include <linux/reboot.h>
21 #include <linux/delay.h>
22 #include <linux/initrd.h>
23 #include <linux/platform_device.h>
24 #include <linux/seq_file.h>
25 #include <linux/ioport.h>
26 #include <linux/console.h>
27 #include <linux/screen_info.h>
28 #include <linux/root_dev.h>
29 #include <linux/notifier.h>
30 #include <linux/cpu.h>
31 #include <linux/unistd.h>
32 #include <linux/serial.h>
33 #include <linux/serial_8250.h>
34 #include <linux/percpu.h>
35 #include <linux/memblock.h>
36 #include <linux/of_platform.h>
37 #include <linux/hugetlb.h>
38 #include <asm/debugfs.h>
39 #include <asm/io.h>
40 #include <asm/paca.h>
41 #include <asm/prom.h>
42 #include <asm/processor.h>
43 #include <asm/vdso_datapage.h>
44 #include <asm/pgtable.h>
45 #include <asm/smp.h>
46 #include <asm/elf.h>
47 #include <asm/machdep.h>
48 #include <asm/time.h>
49 #include <asm/cputable.h>
50 #include <asm/sections.h>
51 #include <asm/firmware.h>
52 #include <asm/btext.h>
53 #include <asm/nvram.h>
54 #include <asm/setup.h>
55 #include <asm/rtas.h>
56 #include <asm/iommu.h>
57 #include <asm/serial.h>
58 #include <asm/cache.h>
59 #include <asm/page.h>
60 #include <asm/mmu.h>
61 #include <asm/xmon.h>
62 #include <asm/cputhreads.h>
63 #include <mm/mmu_decl.h>
64 #include <asm/fadump.h>
65 #include <asm/udbg.h>
66 #include <asm/hugetlb.h>
67 #include <asm/livepatch.h>
68 #include <asm/mmu_context.h>
69 #include <asm/cpu_has_feature.h>
70 
71 #include "setup.h"
72 
73 #ifdef DEBUG
74 #include <asm/udbg.h>
75 #define DBG(fmt...) udbg_printf(fmt)
76 #else
77 #define DBG(fmt...)
78 #endif
79 
80 /* The main machine-dep calls structure
81  */
82 struct machdep_calls ppc_md;
83 EXPORT_SYMBOL(ppc_md);
84 struct machdep_calls *machine_id;
85 EXPORT_SYMBOL(machine_id);
86 
87 int boot_cpuid = -1;
88 EXPORT_SYMBOL_GPL(boot_cpuid);
89 
90 /*
91  * These are used in binfmt_elf.c to put aux entries on the stack
92  * for each elf executable being started.
93  */
94 int dcache_bsize;
95 int icache_bsize;
96 int ucache_bsize;
97 
98 
99 unsigned long klimit = (unsigned long) _end;
100 
101 /*
102  * This still seems to be needed... -- paulus
103  */
104 struct screen_info screen_info = {
105 	.orig_x = 0,
106 	.orig_y = 25,
107 	.orig_video_cols = 80,
108 	.orig_video_lines = 25,
109 	.orig_video_isVGA = 1,
110 	.orig_video_points = 16
111 };
112 #if defined(CONFIG_FB_VGA16_MODULE)
113 EXPORT_SYMBOL(screen_info);
114 #endif
115 
116 /* Variables required to store legacy IO irq routing */
117 int of_i8042_kbd_irq;
118 EXPORT_SYMBOL_GPL(of_i8042_kbd_irq);
119 int of_i8042_aux_irq;
120 EXPORT_SYMBOL_GPL(of_i8042_aux_irq);
121 
122 #ifdef __DO_IRQ_CANON
123 /* XXX should go elsewhere eventually */
124 int ppc_do_canonicalize_irqs;
125 EXPORT_SYMBOL(ppc_do_canonicalize_irqs);
126 #endif
127 
128 #ifdef CONFIG_CRASH_CORE
129 /* This keeps a track of which one is the crashing cpu. */
130 int crashing_cpu = -1;
131 #endif
132 
133 /* also used by kexec */
134 void machine_shutdown(void)
135 {
136 #ifdef CONFIG_FA_DUMP
137 	/*
138 	 * if fadump is active, cleanup the fadump registration before we
139 	 * shutdown.
140 	 */
141 	fadump_cleanup();
142 #endif
143 
144 	if (ppc_md.machine_shutdown)
145 		ppc_md.machine_shutdown();
146 }
147 
148 static void machine_hang(void)
149 {
150 	pr_emerg("System Halted, OK to turn off power\n");
151 	local_irq_disable();
152 	while (1)
153 		;
154 }
155 
156 void machine_restart(char *cmd)
157 {
158 	machine_shutdown();
159 	if (ppc_md.restart)
160 		ppc_md.restart(cmd);
161 
162 	smp_send_stop();
163 
164 	do_kernel_restart(cmd);
165 	mdelay(1000);
166 
167 	machine_hang();
168 }
169 
170 void machine_power_off(void)
171 {
172 	machine_shutdown();
173 	if (pm_power_off)
174 		pm_power_off();
175 
176 	smp_send_stop();
177 	machine_hang();
178 }
179 /* Used by the G5 thermal driver */
180 EXPORT_SYMBOL_GPL(machine_power_off);
181 
182 void (*pm_power_off)(void);
183 EXPORT_SYMBOL_GPL(pm_power_off);
184 
185 void machine_halt(void)
186 {
187 	machine_shutdown();
188 	if (ppc_md.halt)
189 		ppc_md.halt();
190 
191 	smp_send_stop();
192 	machine_hang();
193 }
194 
195 #ifdef CONFIG_SMP
196 DEFINE_PER_CPU(unsigned int, cpu_pvr);
197 #endif
198 
199 static void show_cpuinfo_summary(struct seq_file *m)
200 {
201 	struct device_node *root;
202 	const char *model = NULL;
203 #if defined(CONFIG_SMP) && defined(CONFIG_PPC32)
204 	unsigned long bogosum = 0;
205 	int i;
206 	for_each_online_cpu(i)
207 		bogosum += loops_per_jiffy;
208 	seq_printf(m, "total bogomips\t: %lu.%02lu\n",
209 		   bogosum/(500000/HZ), bogosum/(5000/HZ) % 100);
210 #endif /* CONFIG_SMP && CONFIG_PPC32 */
211 	seq_printf(m, "timebase\t: %lu\n", ppc_tb_freq);
212 	if (ppc_md.name)
213 		seq_printf(m, "platform\t: %s\n", ppc_md.name);
214 	root = of_find_node_by_path("/");
215 	if (root)
216 		model = of_get_property(root, "model", NULL);
217 	if (model)
218 		seq_printf(m, "model\t\t: %s\n", model);
219 	of_node_put(root);
220 
221 	if (ppc_md.show_cpuinfo != NULL)
222 		ppc_md.show_cpuinfo(m);
223 
224 #ifdef CONFIG_PPC32
225 	/* Display the amount of memory */
226 	seq_printf(m, "Memory\t\t: %d MB\n",
227 		   (unsigned int)(total_memory / (1024 * 1024)));
228 #endif
229 }
230 
231 static int show_cpuinfo(struct seq_file *m, void *v)
232 {
233 	unsigned long cpu_id = (unsigned long)v - 1;
234 	unsigned int pvr;
235 	unsigned long proc_freq;
236 	unsigned short maj;
237 	unsigned short min;
238 
239 #ifdef CONFIG_SMP
240 	pvr = per_cpu(cpu_pvr, cpu_id);
241 #else
242 	pvr = mfspr(SPRN_PVR);
243 #endif
244 	maj = (pvr >> 8) & 0xFF;
245 	min = pvr & 0xFF;
246 
247 	seq_printf(m, "processor\t: %lu\n", cpu_id);
248 	seq_printf(m, "cpu\t\t: ");
249 
250 	if (cur_cpu_spec->pvr_mask && cur_cpu_spec->cpu_name)
251 		seq_printf(m, "%s", cur_cpu_spec->cpu_name);
252 	else
253 		seq_printf(m, "unknown (%08x)", pvr);
254 
255 #ifdef CONFIG_ALTIVEC
256 	if (cpu_has_feature(CPU_FTR_ALTIVEC))
257 		seq_printf(m, ", altivec supported");
258 #endif /* CONFIG_ALTIVEC */
259 
260 	seq_printf(m, "\n");
261 
262 #ifdef CONFIG_TAU
263 	if (cur_cpu_spec->cpu_features & CPU_FTR_TAU) {
264 #ifdef CONFIG_TAU_AVERAGE
265 		/* more straightforward, but potentially misleading */
266 		seq_printf(m,  "temperature \t: %u C (uncalibrated)\n",
267 			   cpu_temp(cpu_id));
268 #else
269 		/* show the actual temp sensor range */
270 		u32 temp;
271 		temp = cpu_temp_both(cpu_id);
272 		seq_printf(m, "temperature \t: %u-%u C (uncalibrated)\n",
273 			   temp & 0xff, temp >> 16);
274 #endif
275 	}
276 #endif /* CONFIG_TAU */
277 
278 	/*
279 	 * Platforms that have variable clock rates, should implement
280 	 * the method ppc_md.get_proc_freq() that reports the clock
281 	 * rate of a given cpu. The rest can use ppc_proc_freq to
282 	 * report the clock rate that is same across all cpus.
283 	 */
284 	if (ppc_md.get_proc_freq)
285 		proc_freq = ppc_md.get_proc_freq(cpu_id);
286 	else
287 		proc_freq = ppc_proc_freq;
288 
289 	if (proc_freq)
290 		seq_printf(m, "clock\t\t: %lu.%06luMHz\n",
291 			   proc_freq / 1000000, proc_freq % 1000000);
292 
293 	if (ppc_md.show_percpuinfo != NULL)
294 		ppc_md.show_percpuinfo(m, cpu_id);
295 
296 	/* If we are a Freescale core do a simple check so
297 	 * we dont have to keep adding cases in the future */
298 	if (PVR_VER(pvr) & 0x8000) {
299 		switch (PVR_VER(pvr)) {
300 		case 0x8000:	/* 7441/7450/7451, Voyager */
301 		case 0x8001:	/* 7445/7455, Apollo 6 */
302 		case 0x8002:	/* 7447/7457, Apollo 7 */
303 		case 0x8003:	/* 7447A, Apollo 7 PM */
304 		case 0x8004:	/* 7448, Apollo 8 */
305 		case 0x800c:	/* 7410, Nitro */
306 			maj = ((pvr >> 8) & 0xF);
307 			min = PVR_MIN(pvr);
308 			break;
309 		default:	/* e500/book-e */
310 			maj = PVR_MAJ(pvr);
311 			min = PVR_MIN(pvr);
312 			break;
313 		}
314 	} else {
315 		switch (PVR_VER(pvr)) {
316 			case 0x0020:	/* 403 family */
317 				maj = PVR_MAJ(pvr) + 1;
318 				min = PVR_MIN(pvr);
319 				break;
320 			case 0x1008:	/* 740P/750P ?? */
321 				maj = ((pvr >> 8) & 0xFF) - 1;
322 				min = pvr & 0xFF;
323 				break;
324 			case 0x004e: /* POWER9 bits 12-15 give chip type */
325 				maj = (pvr >> 8) & 0x0F;
326 				min = pvr & 0xFF;
327 				break;
328 			default:
329 				maj = (pvr >> 8) & 0xFF;
330 				min = pvr & 0xFF;
331 				break;
332 		}
333 	}
334 
335 	seq_printf(m, "revision\t: %hd.%hd (pvr %04x %04x)\n",
336 		   maj, min, PVR_VER(pvr), PVR_REV(pvr));
337 
338 #ifdef CONFIG_PPC32
339 	seq_printf(m, "bogomips\t: %lu.%02lu\n",
340 		   loops_per_jiffy / (500000/HZ),
341 		   (loops_per_jiffy / (5000/HZ)) % 100);
342 #endif
343 	seq_printf(m, "\n");
344 
345 	/* If this is the last cpu, print the summary */
346 	if (cpumask_next(cpu_id, cpu_online_mask) >= nr_cpu_ids)
347 		show_cpuinfo_summary(m);
348 
349 	return 0;
350 }
351 
352 static void *c_start(struct seq_file *m, loff_t *pos)
353 {
354 	if (*pos == 0)	/* just in case, cpu 0 is not the first */
355 		*pos = cpumask_first(cpu_online_mask);
356 	else
357 		*pos = cpumask_next(*pos - 1, cpu_online_mask);
358 	if ((*pos) < nr_cpu_ids)
359 		return (void *)(unsigned long)(*pos + 1);
360 	return NULL;
361 }
362 
363 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
364 {
365 	(*pos)++;
366 	return c_start(m, pos);
367 }
368 
369 static void c_stop(struct seq_file *m, void *v)
370 {
371 }
372 
373 const struct seq_operations cpuinfo_op = {
374 	.start	= c_start,
375 	.next	= c_next,
376 	.stop	= c_stop,
377 	.show	= show_cpuinfo,
378 };
379 
380 void __init check_for_initrd(void)
381 {
382 #ifdef CONFIG_BLK_DEV_INITRD
383 	DBG(" -> check_for_initrd()  initrd_start=0x%lx  initrd_end=0x%lx\n",
384 	    initrd_start, initrd_end);
385 
386 	/* If we were passed an initrd, set the ROOT_DEV properly if the values
387 	 * look sensible. If not, clear initrd reference.
388 	 */
389 	if (is_kernel_addr(initrd_start) && is_kernel_addr(initrd_end) &&
390 	    initrd_end > initrd_start)
391 		ROOT_DEV = Root_RAM0;
392 	else
393 		initrd_start = initrd_end = 0;
394 
395 	if (initrd_start)
396 		pr_info("Found initrd at 0x%lx:0x%lx\n", initrd_start, initrd_end);
397 
398 	DBG(" <- check_for_initrd()\n");
399 #endif /* CONFIG_BLK_DEV_INITRD */
400 }
401 
402 #ifdef CONFIG_SMP
403 
404 int threads_per_core, threads_per_subcore, threads_shift;
405 cpumask_t threads_core_mask;
406 EXPORT_SYMBOL_GPL(threads_per_core);
407 EXPORT_SYMBOL_GPL(threads_per_subcore);
408 EXPORT_SYMBOL_GPL(threads_shift);
409 EXPORT_SYMBOL_GPL(threads_core_mask);
410 
411 static void __init cpu_init_thread_core_maps(int tpc)
412 {
413 	int i;
414 
415 	threads_per_core = tpc;
416 	threads_per_subcore = tpc;
417 	cpumask_clear(&threads_core_mask);
418 
419 	/* This implementation only supports power of 2 number of threads
420 	 * for simplicity and performance
421 	 */
422 	threads_shift = ilog2(tpc);
423 	BUG_ON(tpc != (1 << threads_shift));
424 
425 	for (i = 0; i < tpc; i++)
426 		cpumask_set_cpu(i, &threads_core_mask);
427 
428 	printk(KERN_INFO "CPU maps initialized for %d thread%s per core\n",
429 	       tpc, tpc > 1 ? "s" : "");
430 	printk(KERN_DEBUG " (thread shift is %d)\n", threads_shift);
431 }
432 
433 
434 u32 *cpu_to_phys_id = NULL;
435 
436 /**
437  * setup_cpu_maps - initialize the following cpu maps:
438  *                  cpu_possible_mask
439  *                  cpu_present_mask
440  *
441  * Having the possible map set up early allows us to restrict allocations
442  * of things like irqstacks to nr_cpu_ids rather than NR_CPUS.
443  *
444  * We do not initialize the online map here; cpus set their own bits in
445  * cpu_online_mask as they come up.
446  *
447  * This function is valid only for Open Firmware systems.  finish_device_tree
448  * must be called before using this.
449  *
450  * While we're here, we may as well set the "physical" cpu ids in the paca.
451  *
452  * NOTE: This must match the parsing done in early_init_dt_scan_cpus.
453  */
454 void __init smp_setup_cpu_maps(void)
455 {
456 	struct device_node *dn;
457 	int cpu = 0;
458 	int nthreads = 1;
459 
460 	DBG("smp_setup_cpu_maps()\n");
461 
462 	cpu_to_phys_id = memblock_alloc(nr_cpu_ids * sizeof(u32),
463 					__alignof__(u32));
464 	if (!cpu_to_phys_id)
465 		panic("%s: Failed to allocate %zu bytes align=0x%zx\n",
466 		      __func__, nr_cpu_ids * sizeof(u32), __alignof__(u32));
467 
468 	for_each_node_by_type(dn, "cpu") {
469 		const __be32 *intserv;
470 		__be32 cpu_be;
471 		int j, len;
472 
473 		DBG("  * %pOF...\n", dn);
474 
475 		intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s",
476 				&len);
477 		if (intserv) {
478 			DBG("    ibm,ppc-interrupt-server#s -> %d threads\n",
479 			    nthreads);
480 		} else {
481 			DBG("    no ibm,ppc-interrupt-server#s -> 1 thread\n");
482 			intserv = of_get_property(dn, "reg", &len);
483 			if (!intserv) {
484 				cpu_be = cpu_to_be32(cpu);
485 				/* XXX: what is this? uninitialized?? */
486 				intserv = &cpu_be;	/* assume logical == phys */
487 				len = 4;
488 			}
489 		}
490 
491 		nthreads = len / sizeof(int);
492 
493 		for (j = 0; j < nthreads && cpu < nr_cpu_ids; j++) {
494 			bool avail;
495 
496 			DBG("    thread %d -> cpu %d (hard id %d)\n",
497 			    j, cpu, be32_to_cpu(intserv[j]));
498 
499 			avail = of_device_is_available(dn);
500 			if (!avail)
501 				avail = !of_property_match_string(dn,
502 						"enable-method", "spin-table");
503 
504 			set_cpu_present(cpu, avail);
505 			set_cpu_possible(cpu, true);
506 			cpu_to_phys_id[cpu] = be32_to_cpu(intserv[j]);
507 			cpu++;
508 		}
509 
510 		if (cpu >= nr_cpu_ids) {
511 			of_node_put(dn);
512 			break;
513 		}
514 	}
515 
516 	/* If no SMT supported, nthreads is forced to 1 */
517 	if (!cpu_has_feature(CPU_FTR_SMT)) {
518 		DBG("  SMT disabled ! nthreads forced to 1\n");
519 		nthreads = 1;
520 	}
521 
522 #ifdef CONFIG_PPC64
523 	/*
524 	 * On pSeries LPAR, we need to know how many cpus
525 	 * could possibly be added to this partition.
526 	 */
527 	if (firmware_has_feature(FW_FEATURE_LPAR) &&
528 	    (dn = of_find_node_by_path("/rtas"))) {
529 		int num_addr_cell, num_size_cell, maxcpus;
530 		const __be32 *ireg;
531 
532 		num_addr_cell = of_n_addr_cells(dn);
533 		num_size_cell = of_n_size_cells(dn);
534 
535 		ireg = of_get_property(dn, "ibm,lrdr-capacity", NULL);
536 
537 		if (!ireg)
538 			goto out;
539 
540 		maxcpus = be32_to_cpup(ireg + num_addr_cell + num_size_cell);
541 
542 		/* Double maxcpus for processors which have SMT capability */
543 		if (cpu_has_feature(CPU_FTR_SMT))
544 			maxcpus *= nthreads;
545 
546 		if (maxcpus > nr_cpu_ids) {
547 			printk(KERN_WARNING
548 			       "Partition configured for %d cpus, "
549 			       "operating system maximum is %u.\n",
550 			       maxcpus, nr_cpu_ids);
551 			maxcpus = nr_cpu_ids;
552 		} else
553 			printk(KERN_INFO "Partition configured for %d cpus.\n",
554 			       maxcpus);
555 
556 		for (cpu = 0; cpu < maxcpus; cpu++)
557 			set_cpu_possible(cpu, true);
558 	out:
559 		of_node_put(dn);
560 	}
561 	vdso_data->processorCount = num_present_cpus();
562 #endif /* CONFIG_PPC64 */
563 
564         /* Initialize CPU <=> thread mapping/
565 	 *
566 	 * WARNING: We assume that the number of threads is the same for
567 	 * every CPU in the system. If that is not the case, then some code
568 	 * here will have to be reworked
569 	 */
570 	cpu_init_thread_core_maps(nthreads);
571 
572 	/* Now that possible cpus are set, set nr_cpu_ids for later use */
573 	setup_nr_cpu_ids();
574 
575 	free_unused_pacas();
576 }
577 #endif /* CONFIG_SMP */
578 
579 #ifdef CONFIG_PCSPKR_PLATFORM
580 static __init int add_pcspkr(void)
581 {
582 	struct device_node *np;
583 	struct platform_device *pd;
584 	int ret;
585 
586 	np = of_find_compatible_node(NULL, NULL, "pnpPNP,100");
587 	of_node_put(np);
588 	if (!np)
589 		return -ENODEV;
590 
591 	pd = platform_device_alloc("pcspkr", -1);
592 	if (!pd)
593 		return -ENOMEM;
594 
595 	ret = platform_device_add(pd);
596 	if (ret)
597 		platform_device_put(pd);
598 
599 	return ret;
600 }
601 device_initcall(add_pcspkr);
602 #endif	/* CONFIG_PCSPKR_PLATFORM */
603 
604 void probe_machine(void)
605 {
606 	extern struct machdep_calls __machine_desc_start;
607 	extern struct machdep_calls __machine_desc_end;
608 	unsigned int i;
609 
610 	/*
611 	 * Iterate all ppc_md structures until we find the proper
612 	 * one for the current machine type
613 	 */
614 	DBG("Probing machine type ...\n");
615 
616 	/*
617 	 * Check ppc_md is empty, if not we have a bug, ie, we setup an
618 	 * entry before probe_machine() which will be overwritten
619 	 */
620 	for (i = 0; i < (sizeof(ppc_md) / sizeof(void *)); i++) {
621 		if (((void **)&ppc_md)[i]) {
622 			printk(KERN_ERR "Entry %d in ppc_md non empty before"
623 			       " machine probe !\n", i);
624 		}
625 	}
626 
627 	for (machine_id = &__machine_desc_start;
628 	     machine_id < &__machine_desc_end;
629 	     machine_id++) {
630 		DBG("  %s ...", machine_id->name);
631 		memcpy(&ppc_md, machine_id, sizeof(struct machdep_calls));
632 		if (ppc_md.probe()) {
633 			DBG(" match !\n");
634 			break;
635 		}
636 		DBG("\n");
637 	}
638 	/* What can we do if we didn't find ? */
639 	if (machine_id >= &__machine_desc_end) {
640 		pr_err("No suitable machine description found !\n");
641 		for (;;);
642 	}
643 
644 	printk(KERN_INFO "Using %s machine description\n", ppc_md.name);
645 }
646 
647 /* Match a class of boards, not a specific device configuration. */
648 int check_legacy_ioport(unsigned long base_port)
649 {
650 	struct device_node *parent, *np = NULL;
651 	int ret = -ENODEV;
652 
653 	switch(base_port) {
654 	case I8042_DATA_REG:
655 		if (!(np = of_find_compatible_node(NULL, NULL, "pnpPNP,303")))
656 			np = of_find_compatible_node(NULL, NULL, "pnpPNP,f03");
657 		if (np) {
658 			parent = of_get_parent(np);
659 
660 			of_i8042_kbd_irq = irq_of_parse_and_map(parent, 0);
661 			if (!of_i8042_kbd_irq)
662 				of_i8042_kbd_irq = 1;
663 
664 			of_i8042_aux_irq = irq_of_parse_and_map(parent, 1);
665 			if (!of_i8042_aux_irq)
666 				of_i8042_aux_irq = 12;
667 
668 			of_node_put(np);
669 			np = parent;
670 			break;
671 		}
672 		np = of_find_node_by_type(NULL, "8042");
673 		/* Pegasos has no device_type on its 8042 node, look for the
674 		 * name instead */
675 		if (!np)
676 			np = of_find_node_by_name(NULL, "8042");
677 		if (np) {
678 			of_i8042_kbd_irq = 1;
679 			of_i8042_aux_irq = 12;
680 		}
681 		break;
682 	case FDC_BASE: /* FDC1 */
683 		np = of_find_node_by_type(NULL, "fdc");
684 		break;
685 	default:
686 		/* ipmi is supposed to fail here */
687 		break;
688 	}
689 	if (!np)
690 		return ret;
691 	parent = of_get_parent(np);
692 	if (parent) {
693 		if (of_node_is_type(parent, "isa"))
694 			ret = 0;
695 		of_node_put(parent);
696 	}
697 	of_node_put(np);
698 	return ret;
699 }
700 EXPORT_SYMBOL(check_legacy_ioport);
701 
702 static int ppc_panic_event(struct notifier_block *this,
703                              unsigned long event, void *ptr)
704 {
705 	/*
706 	 * panic does a local_irq_disable, but we really
707 	 * want interrupts to be hard disabled.
708 	 */
709 	hard_irq_disable();
710 
711 	/*
712 	 * If firmware-assisted dump has been registered then trigger
713 	 * firmware-assisted dump and let firmware handle everything else.
714 	 */
715 	crash_fadump(NULL, ptr);
716 	if (ppc_md.panic)
717 		ppc_md.panic(ptr);  /* May not return */
718 	return NOTIFY_DONE;
719 }
720 
721 static struct notifier_block ppc_panic_block = {
722 	.notifier_call = ppc_panic_event,
723 	.priority = INT_MIN /* may not return; must be done last */
724 };
725 
726 void __init setup_panic(void)
727 {
728 	/* PPC64 always does a hard irq disable in its panic handler */
729 	if (!IS_ENABLED(CONFIG_PPC64) && !ppc_md.panic)
730 		return;
731 	atomic_notifier_chain_register(&panic_notifier_list, &ppc_panic_block);
732 }
733 
734 #ifdef CONFIG_CHECK_CACHE_COHERENCY
735 /*
736  * For platforms that have configurable cache-coherency.  This function
737  * checks that the cache coherency setting of the kernel matches the setting
738  * left by the firmware, as indicated in the device tree.  Since a mismatch
739  * will eventually result in DMA failures, we print * and error and call
740  * BUG() in that case.
741  */
742 
743 #ifdef CONFIG_NOT_COHERENT_CACHE
744 #define KERNEL_COHERENCY	0
745 #else
746 #define KERNEL_COHERENCY	1
747 #endif
748 
749 static int __init check_cache_coherency(void)
750 {
751 	struct device_node *np;
752 	const void *prop;
753 	int devtree_coherency;
754 
755 	np = of_find_node_by_path("/");
756 	prop = of_get_property(np, "coherency-off", NULL);
757 	of_node_put(np);
758 
759 	devtree_coherency = prop ? 0 : 1;
760 
761 	if (devtree_coherency != KERNEL_COHERENCY) {
762 		printk(KERN_ERR
763 			"kernel coherency:%s != device tree_coherency:%s\n",
764 			KERNEL_COHERENCY ? "on" : "off",
765 			devtree_coherency ? "on" : "off");
766 		BUG();
767 	}
768 
769 	return 0;
770 }
771 
772 late_initcall(check_cache_coherency);
773 #endif /* CONFIG_CHECK_CACHE_COHERENCY */
774 
775 #ifdef CONFIG_DEBUG_FS
776 struct dentry *powerpc_debugfs_root;
777 EXPORT_SYMBOL(powerpc_debugfs_root);
778 
779 static int powerpc_debugfs_init(void)
780 {
781 	powerpc_debugfs_root = debugfs_create_dir("powerpc", NULL);
782 
783 	return powerpc_debugfs_root == NULL;
784 }
785 arch_initcall(powerpc_debugfs_init);
786 #endif
787 
788 void ppc_printk_progress(char *s, unsigned short hex)
789 {
790 	pr_info("%s\n", s);
791 }
792 
793 void arch_setup_pdev_archdata(struct platform_device *pdev)
794 {
795 	pdev->archdata.dma_mask = DMA_BIT_MASK(32);
796 	pdev->dev.dma_mask = &pdev->archdata.dma_mask;
797 }
798 
799 static __init void print_system_info(void)
800 {
801 	pr_info("-----------------------------------------------------\n");
802 #ifdef CONFIG_PPC_BOOK3S_64
803 	pr_info("ppc64_pft_size    = 0x%llx\n", ppc64_pft_size);
804 #endif
805 #ifdef CONFIG_PPC_BOOK3S_32
806 	pr_info("Hash_size         = 0x%lx\n", Hash_size);
807 #endif
808 	pr_info("phys_mem_size     = 0x%llx\n",
809 		(unsigned long long)memblock_phys_mem_size());
810 
811 	pr_info("dcache_bsize      = 0x%x\n", dcache_bsize);
812 	pr_info("icache_bsize      = 0x%x\n", icache_bsize);
813 	if (ucache_bsize != 0)
814 		pr_info("ucache_bsize      = 0x%x\n", ucache_bsize);
815 
816 	pr_info("cpu_features      = 0x%016lx\n", cur_cpu_spec->cpu_features);
817 	pr_info("  possible        = 0x%016lx\n",
818 		(unsigned long)CPU_FTRS_POSSIBLE);
819 	pr_info("  always          = 0x%016lx\n",
820 		(unsigned long)CPU_FTRS_ALWAYS);
821 	pr_info("cpu_user_features = 0x%08x 0x%08x\n",
822 		cur_cpu_spec->cpu_user_features,
823 		cur_cpu_spec->cpu_user_features2);
824 	pr_info("mmu_features      = 0x%08x\n", cur_cpu_spec->mmu_features);
825 #ifdef CONFIG_PPC64
826 	pr_info("firmware_features = 0x%016lx\n", powerpc_firmware_features);
827 #endif
828 
829 #ifdef CONFIG_PPC_BOOK3S_64
830 	if (htab_address)
831 		pr_info("htab_address      = 0x%p\n", htab_address);
832 	if (htab_hash_mask)
833 		pr_info("htab_hash_mask    = 0x%lx\n", htab_hash_mask);
834 #endif
835 #ifdef CONFIG_PPC_BOOK3S_32
836 	if (Hash)
837 		pr_info("Hash              = 0x%p\n", Hash);
838 	if (Hash_mask)
839 		pr_info("Hash_mask         = 0x%lx\n", Hash_mask);
840 #endif
841 
842 	if (PHYSICAL_START > 0)
843 		pr_info("physical_start    = 0x%llx\n",
844 		       (unsigned long long)PHYSICAL_START);
845 	pr_info("-----------------------------------------------------\n");
846 }
847 
848 #ifdef CONFIG_SMP
849 static void smp_setup_pacas(void)
850 {
851 	int cpu;
852 
853 	for_each_possible_cpu(cpu) {
854 		if (cpu == smp_processor_id())
855 			continue;
856 		allocate_paca(cpu);
857 		set_hard_smp_processor_id(cpu, cpu_to_phys_id[cpu]);
858 	}
859 
860 	memblock_free(__pa(cpu_to_phys_id), nr_cpu_ids * sizeof(u32));
861 	cpu_to_phys_id = NULL;
862 }
863 #endif
864 
865 /*
866  * Called into from start_kernel this initializes memblock, which is used
867  * to manage page allocation until mem_init is called.
868  */
869 void __init setup_arch(char **cmdline_p)
870 {
871 	*cmdline_p = boot_command_line;
872 
873 	/* Set a half-reasonable default so udelay does something sensible */
874 	loops_per_jiffy = 500000000 / HZ;
875 
876 	/* Unflatten the device-tree passed by prom_init or kexec */
877 	unflatten_device_tree();
878 
879 	/*
880 	 * Initialize cache line/block info from device-tree (on ppc64) or
881 	 * just cputable (on ppc32).
882 	 */
883 	initialize_cache_info();
884 
885 	/* Initialize RTAS if available. */
886 	rtas_initialize();
887 
888 	/* Check if we have an initrd provided via the device-tree. */
889 	check_for_initrd();
890 
891 	/* Probe the machine type, establish ppc_md. */
892 	probe_machine();
893 
894 	/* Setup panic notifier if requested by the platform. */
895 	setup_panic();
896 
897 	/*
898 	 * Configure ppc_md.power_save (ppc32 only, 64-bit machines do
899 	 * it from their respective probe() function.
900 	 */
901 	setup_power_save();
902 
903 	/* Discover standard serial ports. */
904 	find_legacy_serial_ports();
905 
906 	/* Register early console with the printk subsystem. */
907 	register_early_udbg_console();
908 
909 	/* Setup the various CPU maps based on the device-tree. */
910 	smp_setup_cpu_maps();
911 
912 	/* Initialize xmon. */
913 	xmon_setup();
914 
915 	/* Check the SMT related command line arguments (ppc64). */
916 	check_smt_enabled();
917 
918 	/* Parse memory topology */
919 	mem_topology_setup();
920 
921 	/*
922 	 * Release secondary cpus out of their spinloops at 0x60 now that
923 	 * we can map physical -> logical CPU ids.
924 	 *
925 	 * Freescale Book3e parts spin in a loop provided by firmware,
926 	 * so smp_release_cpus() does nothing for them.
927 	 */
928 #ifdef CONFIG_SMP
929 	smp_setup_pacas();
930 
931 	/* On BookE, setup per-core TLB data structures. */
932 	setup_tlb_core_data();
933 
934 	smp_release_cpus();
935 #endif
936 
937 	/* Print various info about the machine that has been gathered so far. */
938 	print_system_info();
939 
940 	/* Reserve large chunks of memory for use by CMA for KVM. */
941 	kvm_cma_reserve();
942 
943 	klp_init_thread_info(&init_task);
944 
945 	init_mm.start_code = (unsigned long)_stext;
946 	init_mm.end_code = (unsigned long) _etext;
947 	init_mm.end_data = (unsigned long) _edata;
948 	init_mm.brk = klimit;
949 
950 #ifdef CONFIG_PPC_MM_SLICES
951 #ifdef CONFIG_PPC64
952 	if (!radix_enabled())
953 		init_mm.context.slb_addr_limit = DEFAULT_MAP_WINDOW_USER64;
954 #elif defined(CONFIG_PPC_8xx)
955 	init_mm.context.slb_addr_limit = DEFAULT_MAP_WINDOW;
956 #else
957 #error	"context.addr_limit not initialized."
958 #endif
959 #endif
960 
961 #ifdef CONFIG_SPAPR_TCE_IOMMU
962 	mm_iommu_init(&init_mm);
963 #endif
964 	irqstack_early_init();
965 	exc_lvl_early_init();
966 	emergency_stack_init();
967 
968 	initmem_init();
969 
970 	early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT);
971 
972 #ifdef CONFIG_DUMMY_CONSOLE
973 	conswitchp = &dummy_con;
974 #endif
975 	if (ppc_md.setup_arch)
976 		ppc_md.setup_arch();
977 
978 	setup_barrier_nospec();
979 	setup_spectre_v2();
980 
981 	paging_init();
982 
983 	/* Initialize the MMU context management stuff. */
984 	mmu_context_init();
985 
986 #ifdef CONFIG_PPC64
987 	/* Interrupt code needs to be 64K-aligned. */
988 	if ((unsigned long)_stext & 0xffff)
989 		panic("Kernelbase not 64K-aligned (0x%lx)!\n",
990 		      (unsigned long)_stext);
991 #endif
992 }
993