xref: /linux/arch/powerpc/kernel/setup-common.c (revision 92d9dfda8b547cc292af27e11e11c9eff3bb574f)
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 
196 #ifdef CONFIG_TAU
197 extern u32 cpu_temp(unsigned long cpu);
198 extern u32 cpu_temp_both(unsigned long cpu);
199 #endif /* CONFIG_TAU */
200 
201 #ifdef CONFIG_SMP
202 DEFINE_PER_CPU(unsigned int, cpu_pvr);
203 #endif
204 
205 static void show_cpuinfo_summary(struct seq_file *m)
206 {
207 	struct device_node *root;
208 	const char *model = NULL;
209 #if defined(CONFIG_SMP) && defined(CONFIG_PPC32)
210 	unsigned long bogosum = 0;
211 	int i;
212 	for_each_online_cpu(i)
213 		bogosum += loops_per_jiffy;
214 	seq_printf(m, "total bogomips\t: %lu.%02lu\n",
215 		   bogosum/(500000/HZ), bogosum/(5000/HZ) % 100);
216 #endif /* CONFIG_SMP && CONFIG_PPC32 */
217 	seq_printf(m, "timebase\t: %lu\n", ppc_tb_freq);
218 	if (ppc_md.name)
219 		seq_printf(m, "platform\t: %s\n", ppc_md.name);
220 	root = of_find_node_by_path("/");
221 	if (root)
222 		model = of_get_property(root, "model", NULL);
223 	if (model)
224 		seq_printf(m, "model\t\t: %s\n", model);
225 	of_node_put(root);
226 
227 	if (ppc_md.show_cpuinfo != NULL)
228 		ppc_md.show_cpuinfo(m);
229 
230 #ifdef CONFIG_PPC32
231 	/* Display the amount of memory */
232 	seq_printf(m, "Memory\t\t: %d MB\n",
233 		   (unsigned int)(total_memory / (1024 * 1024)));
234 #endif
235 }
236 
237 static int show_cpuinfo(struct seq_file *m, void *v)
238 {
239 	unsigned long cpu_id = (unsigned long)v - 1;
240 	unsigned int pvr;
241 	unsigned long proc_freq;
242 	unsigned short maj;
243 	unsigned short min;
244 
245 	/* We only show online cpus: disable preempt (overzealous, I
246 	 * knew) to prevent cpu going down. */
247 	preempt_disable();
248 	if (!cpu_online(cpu_id)) {
249 		preempt_enable();
250 		return 0;
251 	}
252 
253 #ifdef CONFIG_SMP
254 	pvr = per_cpu(cpu_pvr, cpu_id);
255 #else
256 	pvr = mfspr(SPRN_PVR);
257 #endif
258 	maj = (pvr >> 8) & 0xFF;
259 	min = pvr & 0xFF;
260 
261 	seq_printf(m, "processor\t: %lu\n", cpu_id);
262 	seq_printf(m, "cpu\t\t: ");
263 
264 	if (cur_cpu_spec->pvr_mask && cur_cpu_spec->cpu_name)
265 		seq_printf(m, "%s", cur_cpu_spec->cpu_name);
266 	else
267 		seq_printf(m, "unknown (%08x)", pvr);
268 
269 #ifdef CONFIG_ALTIVEC
270 	if (cpu_has_feature(CPU_FTR_ALTIVEC))
271 		seq_printf(m, ", altivec supported");
272 #endif /* CONFIG_ALTIVEC */
273 
274 	seq_printf(m, "\n");
275 
276 #ifdef CONFIG_TAU
277 	if (cur_cpu_spec->cpu_features & CPU_FTR_TAU) {
278 #ifdef CONFIG_TAU_AVERAGE
279 		/* more straightforward, but potentially misleading */
280 		seq_printf(m,  "temperature \t: %u C (uncalibrated)\n",
281 			   cpu_temp(cpu_id));
282 #else
283 		/* show the actual temp sensor range */
284 		u32 temp;
285 		temp = cpu_temp_both(cpu_id);
286 		seq_printf(m, "temperature \t: %u-%u C (uncalibrated)\n",
287 			   temp & 0xff, temp >> 16);
288 #endif
289 	}
290 #endif /* CONFIG_TAU */
291 
292 	/*
293 	 * Platforms that have variable clock rates, should implement
294 	 * the method ppc_md.get_proc_freq() that reports the clock
295 	 * rate of a given cpu. The rest can use ppc_proc_freq to
296 	 * report the clock rate that is same across all cpus.
297 	 */
298 	if (ppc_md.get_proc_freq)
299 		proc_freq = ppc_md.get_proc_freq(cpu_id);
300 	else
301 		proc_freq = ppc_proc_freq;
302 
303 	if (proc_freq)
304 		seq_printf(m, "clock\t\t: %lu.%06luMHz\n",
305 			   proc_freq / 1000000, proc_freq % 1000000);
306 
307 	if (ppc_md.show_percpuinfo != NULL)
308 		ppc_md.show_percpuinfo(m, cpu_id);
309 
310 	/* If we are a Freescale core do a simple check so
311 	 * we dont have to keep adding cases in the future */
312 	if (PVR_VER(pvr) & 0x8000) {
313 		switch (PVR_VER(pvr)) {
314 		case 0x8000:	/* 7441/7450/7451, Voyager */
315 		case 0x8001:	/* 7445/7455, Apollo 6 */
316 		case 0x8002:	/* 7447/7457, Apollo 7 */
317 		case 0x8003:	/* 7447A, Apollo 7 PM */
318 		case 0x8004:	/* 7448, Apollo 8 */
319 		case 0x800c:	/* 7410, Nitro */
320 			maj = ((pvr >> 8) & 0xF);
321 			min = PVR_MIN(pvr);
322 			break;
323 		default:	/* e500/book-e */
324 			maj = PVR_MAJ(pvr);
325 			min = PVR_MIN(pvr);
326 			break;
327 		}
328 	} else {
329 		switch (PVR_VER(pvr)) {
330 			case 0x0020:	/* 403 family */
331 				maj = PVR_MAJ(pvr) + 1;
332 				min = PVR_MIN(pvr);
333 				break;
334 			case 0x1008:	/* 740P/750P ?? */
335 				maj = ((pvr >> 8) & 0xFF) - 1;
336 				min = pvr & 0xFF;
337 				break;
338 			default:
339 				maj = (pvr >> 8) & 0xFF;
340 				min = pvr & 0xFF;
341 				break;
342 		}
343 	}
344 
345 	seq_printf(m, "revision\t: %hd.%hd (pvr %04x %04x)\n",
346 		   maj, min, PVR_VER(pvr), PVR_REV(pvr));
347 
348 #ifdef CONFIG_PPC32
349 	seq_printf(m, "bogomips\t: %lu.%02lu\n",
350 		   loops_per_jiffy / (500000/HZ),
351 		   (loops_per_jiffy / (5000/HZ)) % 100);
352 #endif
353 
354 #ifdef CONFIG_SMP
355 	seq_printf(m, "\n");
356 #endif
357 
358 	preempt_enable();
359 
360 	/* If this is the last cpu, print the summary */
361 	if (cpumask_next(cpu_id, cpu_online_mask) >= nr_cpu_ids)
362 		show_cpuinfo_summary(m);
363 
364 	return 0;
365 }
366 
367 static void *c_start(struct seq_file *m, loff_t *pos)
368 {
369 	if (*pos == 0)	/* just in case, cpu 0 is not the first */
370 		*pos = cpumask_first(cpu_online_mask);
371 	else
372 		*pos = cpumask_next(*pos - 1, cpu_online_mask);
373 	if ((*pos) < nr_cpu_ids)
374 		return (void *)(unsigned long)(*pos + 1);
375 	return NULL;
376 }
377 
378 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
379 {
380 	(*pos)++;
381 	return c_start(m, pos);
382 }
383 
384 static void c_stop(struct seq_file *m, void *v)
385 {
386 }
387 
388 const struct seq_operations cpuinfo_op = {
389 	.start =c_start,
390 	.next =	c_next,
391 	.stop =	c_stop,
392 	.show =	show_cpuinfo,
393 };
394 
395 void __init check_for_initrd(void)
396 {
397 #ifdef CONFIG_BLK_DEV_INITRD
398 	DBG(" -> check_for_initrd()  initrd_start=0x%lx  initrd_end=0x%lx\n",
399 	    initrd_start, initrd_end);
400 
401 	/* If we were passed an initrd, set the ROOT_DEV properly if the values
402 	 * look sensible. If not, clear initrd reference.
403 	 */
404 	if (is_kernel_addr(initrd_start) && is_kernel_addr(initrd_end) &&
405 	    initrd_end > initrd_start)
406 		ROOT_DEV = Root_RAM0;
407 	else
408 		initrd_start = initrd_end = 0;
409 
410 	if (initrd_start)
411 		pr_info("Found initrd at 0x%lx:0x%lx\n", initrd_start, initrd_end);
412 
413 	DBG(" <- check_for_initrd()\n");
414 #endif /* CONFIG_BLK_DEV_INITRD */
415 }
416 
417 #ifdef CONFIG_SMP
418 
419 int threads_per_core, threads_per_subcore, threads_shift;
420 cpumask_t threads_core_mask;
421 EXPORT_SYMBOL_GPL(threads_per_core);
422 EXPORT_SYMBOL_GPL(threads_per_subcore);
423 EXPORT_SYMBOL_GPL(threads_shift);
424 EXPORT_SYMBOL_GPL(threads_core_mask);
425 
426 static void __init cpu_init_thread_core_maps(int tpc)
427 {
428 	int i;
429 
430 	threads_per_core = tpc;
431 	threads_per_subcore = tpc;
432 	cpumask_clear(&threads_core_mask);
433 
434 	/* This implementation only supports power of 2 number of threads
435 	 * for simplicity and performance
436 	 */
437 	threads_shift = ilog2(tpc);
438 	BUG_ON(tpc != (1 << threads_shift));
439 
440 	for (i = 0; i < tpc; i++)
441 		cpumask_set_cpu(i, &threads_core_mask);
442 
443 	printk(KERN_INFO "CPU maps initialized for %d thread%s per core\n",
444 	       tpc, tpc > 1 ? "s" : "");
445 	printk(KERN_DEBUG " (thread shift is %d)\n", threads_shift);
446 }
447 
448 
449 /**
450  * setup_cpu_maps - initialize the following cpu maps:
451  *                  cpu_possible_mask
452  *                  cpu_present_mask
453  *
454  * Having the possible map set up early allows us to restrict allocations
455  * of things like irqstacks to nr_cpu_ids rather than NR_CPUS.
456  *
457  * We do not initialize the online map here; cpus set their own bits in
458  * cpu_online_mask as they come up.
459  *
460  * This function is valid only for Open Firmware systems.  finish_device_tree
461  * must be called before using this.
462  *
463  * While we're here, we may as well set the "physical" cpu ids in the paca.
464  *
465  * NOTE: This must match the parsing done in early_init_dt_scan_cpus.
466  */
467 void __init smp_setup_cpu_maps(void)
468 {
469 	struct device_node *dn = NULL;
470 	int cpu = 0;
471 	int nthreads = 1;
472 
473 	DBG("smp_setup_cpu_maps()\n");
474 
475 	while ((dn = of_find_node_by_type(dn, "cpu")) && cpu < nr_cpu_ids) {
476 		const __be32 *intserv;
477 		__be32 cpu_be;
478 		int j, len;
479 
480 		DBG("  * %s...\n", dn->full_name);
481 
482 		intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s",
483 				&len);
484 		if (intserv) {
485 			DBG("    ibm,ppc-interrupt-server#s -> %d threads\n",
486 			    nthreads);
487 		} else {
488 			DBG("    no ibm,ppc-interrupt-server#s -> 1 thread\n");
489 			intserv = of_get_property(dn, "reg", &len);
490 			if (!intserv) {
491 				cpu_be = cpu_to_be32(cpu);
492 				intserv = &cpu_be;	/* assume logical == phys */
493 				len = 4;
494 			}
495 		}
496 
497 		nthreads = len / sizeof(int);
498 
499 		for (j = 0; j < nthreads && cpu < nr_cpu_ids; j++) {
500 			bool avail;
501 
502 			DBG("    thread %d -> cpu %d (hard id %d)\n",
503 			    j, cpu, be32_to_cpu(intserv[j]));
504 
505 			avail = of_device_is_available(dn);
506 			if (!avail)
507 				avail = !of_property_match_string(dn,
508 						"enable-method", "spin-table");
509 
510 			set_cpu_present(cpu, avail);
511 			set_hard_smp_processor_id(cpu, be32_to_cpu(intserv[j]));
512 			set_cpu_possible(cpu, true);
513 			cpu++;
514 		}
515 	}
516 
517 	/* If no SMT supported, nthreads is forced to 1 */
518 	if (!cpu_has_feature(CPU_FTR_SMT)) {
519 		DBG("  SMT disabled ! nthreads forced to 1\n");
520 		nthreads = 1;
521 	}
522 
523 #ifdef CONFIG_PPC64
524 	/*
525 	 * On pSeries LPAR, we need to know how many cpus
526 	 * could possibly be added to this partition.
527 	 */
528 	if (firmware_has_feature(FW_FEATURE_LPAR) &&
529 	    (dn = of_find_node_by_path("/rtas"))) {
530 		int num_addr_cell, num_size_cell, maxcpus;
531 		const __be32 *ireg;
532 
533 		num_addr_cell = of_n_addr_cells(dn);
534 		num_size_cell = of_n_size_cells(dn);
535 
536 		ireg = of_get_property(dn, "ibm,lrdr-capacity", NULL);
537 
538 		if (!ireg)
539 			goto out;
540 
541 		maxcpus = be32_to_cpup(ireg + num_addr_cell + num_size_cell);
542 
543 		/* Double maxcpus for processors which have SMT capability */
544 		if (cpu_has_feature(CPU_FTR_SMT))
545 			maxcpus *= nthreads;
546 
547 		if (maxcpus > nr_cpu_ids) {
548 			printk(KERN_WARNING
549 			       "Partition configured for %d cpus, "
550 			       "operating system maximum is %d.\n",
551 			       maxcpus, nr_cpu_ids);
552 			maxcpus = nr_cpu_ids;
553 		} else
554 			printk(KERN_INFO "Partition configured for %d cpus.\n",
555 			       maxcpus);
556 
557 		for (cpu = 0; cpu < maxcpus; cpu++)
558 			set_cpu_possible(cpu, true);
559 	out:
560 		of_node_put(dn);
561 	}
562 	vdso_data->processorCount = num_present_cpus();
563 #endif /* CONFIG_PPC64 */
564 
565         /* Initialize CPU <=> thread mapping/
566 	 *
567 	 * WARNING: We assume that the number of threads is the same for
568 	 * every CPU in the system. If that is not the case, then some code
569 	 * here will have to be reworked
570 	 */
571 	cpu_init_thread_core_maps(nthreads);
572 
573 	/* Now that possible cpus are set, set nr_cpu_ids for later use */
574 	setup_nr_cpu_ids();
575 
576 	free_unused_pacas();
577 }
578 #endif /* CONFIG_SMP */
579 
580 #ifdef CONFIG_PCSPKR_PLATFORM
581 static __init int add_pcspkr(void)
582 {
583 	struct device_node *np;
584 	struct platform_device *pd;
585 	int ret;
586 
587 	np = of_find_compatible_node(NULL, NULL, "pnpPNP,100");
588 	of_node_put(np);
589 	if (!np)
590 		return -ENODEV;
591 
592 	pd = platform_device_alloc("pcspkr", -1);
593 	if (!pd)
594 		return -ENOMEM;
595 
596 	ret = platform_device_add(pd);
597 	if (ret)
598 		platform_device_put(pd);
599 
600 	return ret;
601 }
602 device_initcall(add_pcspkr);
603 #endif	/* CONFIG_PCSPKR_PLATFORM */
604 
605 void probe_machine(void)
606 {
607 	extern struct machdep_calls __machine_desc_start;
608 	extern struct machdep_calls __machine_desc_end;
609 	unsigned int i;
610 
611 	/*
612 	 * Iterate all ppc_md structures until we find the proper
613 	 * one for the current machine type
614 	 */
615 	DBG("Probing machine type ...\n");
616 
617 	/*
618 	 * Check ppc_md is empty, if not we have a bug, ie, we setup an
619 	 * entry before probe_machine() which will be overwritten
620 	 */
621 	for (i = 0; i < (sizeof(ppc_md) / sizeof(void *)); i++) {
622 		if (((void **)&ppc_md)[i]) {
623 			printk(KERN_ERR "Entry %d in ppc_md non empty before"
624 			       " machine probe !\n", i);
625 		}
626 	}
627 
628 	for (machine_id = &__machine_desc_start;
629 	     machine_id < &__machine_desc_end;
630 	     machine_id++) {
631 		DBG("  %s ...", machine_id->name);
632 		memcpy(&ppc_md, machine_id, sizeof(struct machdep_calls));
633 		if (ppc_md.probe()) {
634 			DBG(" match !\n");
635 			break;
636 		}
637 		DBG("\n");
638 	}
639 	/* What can we do if we didn't find ? */
640 	if (machine_id >= &__machine_desc_end) {
641 		DBG("No suitable machine found !\n");
642 		for (;;);
643 	}
644 
645 	printk(KERN_INFO "Using %s machine description\n", ppc_md.name);
646 }
647 
648 /* Match a class of boards, not a specific device configuration. */
649 int check_legacy_ioport(unsigned long base_port)
650 {
651 	struct device_node *parent, *np = NULL;
652 	int ret = -ENODEV;
653 
654 	switch(base_port) {
655 	case I8042_DATA_REG:
656 		if (!(np = of_find_compatible_node(NULL, NULL, "pnpPNP,303")))
657 			np = of_find_compatible_node(NULL, NULL, "pnpPNP,f03");
658 		if (np) {
659 			parent = of_get_parent(np);
660 
661 			of_i8042_kbd_irq = irq_of_parse_and_map(parent, 0);
662 			if (!of_i8042_kbd_irq)
663 				of_i8042_kbd_irq = 1;
664 
665 			of_i8042_aux_irq = irq_of_parse_and_map(parent, 1);
666 			if (!of_i8042_aux_irq)
667 				of_i8042_aux_irq = 12;
668 
669 			of_node_put(np);
670 			np = parent;
671 			break;
672 		}
673 		np = of_find_node_by_type(NULL, "8042");
674 		/* Pegasos has no device_type on its 8042 node, look for the
675 		 * name instead */
676 		if (!np)
677 			np = of_find_node_by_name(NULL, "8042");
678 		if (np) {
679 			of_i8042_kbd_irq = 1;
680 			of_i8042_aux_irq = 12;
681 		}
682 		break;
683 	case FDC_BASE: /* FDC1 */
684 		np = of_find_node_by_type(NULL, "fdc");
685 		break;
686 	default:
687 		/* ipmi is supposed to fail here */
688 		break;
689 	}
690 	if (!np)
691 		return ret;
692 	parent = of_get_parent(np);
693 	if (parent) {
694 		if (strcmp(parent->type, "isa") == 0)
695 			ret = 0;
696 		of_node_put(parent);
697 	}
698 	of_node_put(np);
699 	return ret;
700 }
701 EXPORT_SYMBOL(check_legacy_ioport);
702 
703 static int ppc_panic_event(struct notifier_block *this,
704                              unsigned long event, void *ptr)
705 {
706 	/*
707 	 * If firmware-assisted dump has been registered then trigger
708 	 * firmware-assisted dump and let firmware handle everything else.
709 	 */
710 	crash_fadump(NULL, ptr);
711 	ppc_md.panic(ptr);  /* May not return */
712 	return NOTIFY_DONE;
713 }
714 
715 static struct notifier_block ppc_panic_block = {
716 	.notifier_call = ppc_panic_event,
717 	.priority = INT_MIN /* may not return; must be done last */
718 };
719 
720 void __init setup_panic(void)
721 {
722 	if (!ppc_md.panic)
723 		return;
724 	atomic_notifier_chain_register(&panic_notifier_list, &ppc_panic_block);
725 }
726 
727 #ifdef CONFIG_CHECK_CACHE_COHERENCY
728 /*
729  * For platforms that have configurable cache-coherency.  This function
730  * checks that the cache coherency setting of the kernel matches the setting
731  * left by the firmware, as indicated in the device tree.  Since a mismatch
732  * will eventually result in DMA failures, we print * and error and call
733  * BUG() in that case.
734  */
735 
736 #ifdef CONFIG_NOT_COHERENT_CACHE
737 #define KERNEL_COHERENCY	0
738 #else
739 #define KERNEL_COHERENCY	1
740 #endif
741 
742 static int __init check_cache_coherency(void)
743 {
744 	struct device_node *np;
745 	const void *prop;
746 	int devtree_coherency;
747 
748 	np = of_find_node_by_path("/");
749 	prop = of_get_property(np, "coherency-off", NULL);
750 	of_node_put(np);
751 
752 	devtree_coherency = prop ? 0 : 1;
753 
754 	if (devtree_coherency != KERNEL_COHERENCY) {
755 		printk(KERN_ERR
756 			"kernel coherency:%s != device tree_coherency:%s\n",
757 			KERNEL_COHERENCY ? "on" : "off",
758 			devtree_coherency ? "on" : "off");
759 		BUG();
760 	}
761 
762 	return 0;
763 }
764 
765 late_initcall(check_cache_coherency);
766 #endif /* CONFIG_CHECK_CACHE_COHERENCY */
767 
768 #ifdef CONFIG_DEBUG_FS
769 struct dentry *powerpc_debugfs_root;
770 EXPORT_SYMBOL(powerpc_debugfs_root);
771 
772 static int powerpc_debugfs_init(void)
773 {
774 	powerpc_debugfs_root = debugfs_create_dir("powerpc", NULL);
775 
776 	return powerpc_debugfs_root == NULL;
777 }
778 arch_initcall(powerpc_debugfs_init);
779 #endif
780 
781 void ppc_printk_progress(char *s, unsigned short hex)
782 {
783 	pr_info("%s\n", s);
784 }
785 
786 void arch_setup_pdev_archdata(struct platform_device *pdev)
787 {
788 	pdev->archdata.dma_mask = DMA_BIT_MASK(32);
789 	pdev->dev.dma_mask = &pdev->archdata.dma_mask;
790  	set_dma_ops(&pdev->dev, &dma_direct_ops);
791 }
792 
793 static __init void print_system_info(void)
794 {
795 	pr_info("-----------------------------------------------------\n");
796 #ifdef CONFIG_PPC_STD_MMU_64
797 	pr_info("ppc64_pft_size    = 0x%llx\n", ppc64_pft_size);
798 #endif
799 #ifdef CONFIG_PPC_STD_MMU_32
800 	pr_info("Hash_size         = 0x%lx\n", Hash_size);
801 #endif
802 	pr_info("phys_mem_size     = 0x%llx\n",
803 		(unsigned long long)memblock_phys_mem_size());
804 
805 	pr_info("dcache_bsize      = 0x%x\n", dcache_bsize);
806 	pr_info("icache_bsize      = 0x%x\n", icache_bsize);
807 	if (ucache_bsize != 0)
808 		pr_info("ucache_bsize      = 0x%x\n", ucache_bsize);
809 
810 	pr_info("cpu_features      = 0x%016lx\n", cur_cpu_spec->cpu_features);
811 	pr_info("  possible        = 0x%016lx\n",
812 		(unsigned long)CPU_FTRS_POSSIBLE);
813 	pr_info("  always          = 0x%016lx\n",
814 		(unsigned long)CPU_FTRS_ALWAYS);
815 	pr_info("cpu_user_features = 0x%08x 0x%08x\n",
816 		cur_cpu_spec->cpu_user_features,
817 		cur_cpu_spec->cpu_user_features2);
818 	pr_info("mmu_features      = 0x%08x\n", cur_cpu_spec->mmu_features);
819 #ifdef CONFIG_PPC64
820 	pr_info("firmware_features = 0x%016lx\n", powerpc_firmware_features);
821 #endif
822 
823 #ifdef CONFIG_PPC_STD_MMU_64
824 	if (htab_address)
825 		pr_info("htab_address      = 0x%p\n", htab_address);
826 	if (htab_hash_mask)
827 		pr_info("htab_hash_mask    = 0x%lx\n", htab_hash_mask);
828 #endif
829 #ifdef CONFIG_PPC_STD_MMU_32
830 	if (Hash)
831 		pr_info("Hash              = 0x%p\n", Hash);
832 	if (Hash_mask)
833 		pr_info("Hash_mask         = 0x%lx\n", Hash_mask);
834 #endif
835 
836 	if (PHYSICAL_START > 0)
837 		pr_info("physical_start    = 0x%llx\n",
838 		       (unsigned long long)PHYSICAL_START);
839 	pr_info("-----------------------------------------------------\n");
840 }
841 
842 /*
843  * Called into from start_kernel this initializes memblock, which is used
844  * to manage page allocation until mem_init is called.
845  */
846 void __init setup_arch(char **cmdline_p)
847 {
848 	*cmdline_p = boot_command_line;
849 
850 	/* Set a half-reasonable default so udelay does something sensible */
851 	loops_per_jiffy = 500000000 / HZ;
852 
853 	/* Unflatten the device-tree passed by prom_init or kexec */
854 	unflatten_device_tree();
855 
856 	/*
857 	 * Initialize cache line/block info from device-tree (on ppc64) or
858 	 * just cputable (on ppc32).
859 	 */
860 	initialize_cache_info();
861 
862 	/* Initialize RTAS if available. */
863 	rtas_initialize();
864 
865 	/* Check if we have an initrd provided via the device-tree. */
866 	check_for_initrd();
867 
868 	/* Probe the machine type, establish ppc_md. */
869 	probe_machine();
870 
871 	/* Setup panic notifier if requested by the platform. */
872 	setup_panic();
873 
874 	/*
875 	 * Configure ppc_md.power_save (ppc32 only, 64-bit machines do
876 	 * it from their respective probe() function.
877 	 */
878 	setup_power_save();
879 
880 	/* Discover standard serial ports. */
881 	find_legacy_serial_ports();
882 
883 	/* Register early console with the printk subsystem. */
884 	register_early_udbg_console();
885 
886 	/* Setup the various CPU maps based on the device-tree. */
887 	smp_setup_cpu_maps();
888 
889 	/* Initialize xmon. */
890 	xmon_setup();
891 
892 	/* Check the SMT related command line arguments (ppc64). */
893 	check_smt_enabled();
894 
895 	/* On BookE, setup per-core TLB data structures. */
896 	setup_tlb_core_data();
897 
898 	/*
899 	 * Release secondary cpus out of their spinloops at 0x60 now that
900 	 * we can map physical -> logical CPU ids.
901 	 *
902 	 * Freescale Book3e parts spin in a loop provided by firmware,
903 	 * so smp_release_cpus() does nothing for them.
904 	 */
905 #ifdef CONFIG_SMP
906 	smp_release_cpus();
907 #endif
908 
909 	/* Print various info about the machine that has been gathered so far. */
910 	print_system_info();
911 
912 	/* Reserve large chunks of memory for use by CMA for KVM. */
913 	kvm_cma_reserve();
914 
915 	/*
916 	 * Reserve any gigantic pages requested on the command line.
917 	 * memblock needs to have been initialized by the time this is
918 	 * called since this will reserve memory.
919 	 */
920 	reserve_hugetlb_gpages();
921 
922 	klp_init_thread_info(&init_thread_info);
923 
924 	init_mm.start_code = (unsigned long)_stext;
925 	init_mm.end_code = (unsigned long) _etext;
926 	init_mm.end_data = (unsigned long) _edata;
927 	init_mm.brk = klimit;
928 
929 #ifdef CONFIG_PPC_MM_SLICES
930 #ifdef CONFIG_PPC64
931 	init_mm.context.addr_limit = DEFAULT_MAP_WINDOW_USER64;
932 #else
933 #error	"context.addr_limit not initialized."
934 #endif
935 #endif
936 
937 #ifdef CONFIG_PPC_64K_PAGES
938 	init_mm.context.pte_frag = NULL;
939 #endif
940 #ifdef CONFIG_SPAPR_TCE_IOMMU
941 	mm_iommu_init(&init_mm);
942 #endif
943 	irqstack_early_init();
944 	exc_lvl_early_init();
945 	emergency_stack_init();
946 
947 	initmem_init();
948 
949 #ifdef CONFIG_DUMMY_CONSOLE
950 	conswitchp = &dummy_con;
951 #endif
952 	if (ppc_md.setup_arch)
953 		ppc_md.setup_arch();
954 
955 	paging_init();
956 
957 	/* Initialize the MMU context management stuff. */
958 	mmu_context_init();
959 
960 #ifdef CONFIG_PPC64
961 	/* Interrupt code needs to be 64K-aligned. */
962 	if ((unsigned long)_stext & 0xffff)
963 		panic("Kernelbase not 64K-aligned (0x%lx)!\n",
964 		      (unsigned long)_stext);
965 #endif
966 }
967