xref: /linux/arch/powerpc/kernel/setup-common.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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/debugfs.h>
35 #include <linux/percpu.h>
36 #include <linux/memblock.h>
37 #include <linux/of_platform.h>
38 #include <asm/io.h>
39 #include <asm/paca.h>
40 #include <asm/prom.h>
41 #include <asm/processor.h>
42 #include <asm/vdso_datapage.h>
43 #include <asm/pgtable.h>
44 #include <asm/smp.h>
45 #include <asm/elf.h>
46 #include <asm/machdep.h>
47 #include <asm/time.h>
48 #include <asm/cputable.h>
49 #include <asm/sections.h>
50 #include <asm/firmware.h>
51 #include <asm/btext.h>
52 #include <asm/nvram.h>
53 #include <asm/setup.h>
54 #include <asm/rtas.h>
55 #include <asm/iommu.h>
56 #include <asm/serial.h>
57 #include <asm/cache.h>
58 #include <asm/page.h>
59 #include <asm/mmu.h>
60 #include <asm/xmon.h>
61 #include <asm/cputhreads.h>
62 #include <mm/mmu_decl.h>
63 #include <asm/fadump.h>
64 
65 #ifdef DEBUG
66 #include <asm/udbg.h>
67 #define DBG(fmt...) udbg_printf(fmt)
68 #else
69 #define DBG(fmt...)
70 #endif
71 
72 /* The main machine-dep calls structure
73  */
74 struct machdep_calls ppc_md;
75 EXPORT_SYMBOL(ppc_md);
76 struct machdep_calls *machine_id;
77 EXPORT_SYMBOL(machine_id);
78 
79 int boot_cpuid = -1;
80 EXPORT_SYMBOL_GPL(boot_cpuid);
81 
82 unsigned long klimit = (unsigned long) _end;
83 
84 /*
85  * This still seems to be needed... -- paulus
86  */
87 struct screen_info screen_info = {
88 	.orig_x = 0,
89 	.orig_y = 25,
90 	.orig_video_cols = 80,
91 	.orig_video_lines = 25,
92 	.orig_video_isVGA = 1,
93 	.orig_video_points = 16
94 };
95 #if defined(CONFIG_FB_VGA16_MODULE)
96 EXPORT_SYMBOL(screen_info);
97 #endif
98 
99 /* Variables required to store legacy IO irq routing */
100 int of_i8042_kbd_irq;
101 EXPORT_SYMBOL_GPL(of_i8042_kbd_irq);
102 int of_i8042_aux_irq;
103 EXPORT_SYMBOL_GPL(of_i8042_aux_irq);
104 
105 #ifdef __DO_IRQ_CANON
106 /* XXX should go elsewhere eventually */
107 int ppc_do_canonicalize_irqs;
108 EXPORT_SYMBOL(ppc_do_canonicalize_irqs);
109 #endif
110 
111 /* also used by kexec */
112 void machine_shutdown(void)
113 {
114 #ifdef CONFIG_FA_DUMP
115 	/*
116 	 * if fadump is active, cleanup the fadump registration before we
117 	 * shutdown.
118 	 */
119 	fadump_cleanup();
120 #endif
121 
122 	if (ppc_md.machine_shutdown)
123 		ppc_md.machine_shutdown();
124 }
125 
126 void machine_restart(char *cmd)
127 {
128 	machine_shutdown();
129 	if (ppc_md.restart)
130 		ppc_md.restart(cmd);
131 #ifdef CONFIG_SMP
132 	smp_send_stop();
133 #endif
134 	printk(KERN_EMERG "System Halted, OK to turn off power\n");
135 	local_irq_disable();
136 	while (1) ;
137 }
138 
139 void machine_power_off(void)
140 {
141 	machine_shutdown();
142 	if (pm_power_off)
143 		pm_power_off();
144 #ifdef CONFIG_SMP
145 	smp_send_stop();
146 #endif
147 	printk(KERN_EMERG "System Halted, OK to turn off power\n");
148 	local_irq_disable();
149 	while (1) ;
150 }
151 /* Used by the G5 thermal driver */
152 EXPORT_SYMBOL_GPL(machine_power_off);
153 
154 void (*pm_power_off)(void);
155 EXPORT_SYMBOL_GPL(pm_power_off);
156 
157 void machine_halt(void)
158 {
159 	machine_shutdown();
160 	if (ppc_md.halt)
161 		ppc_md.halt();
162 #ifdef CONFIG_SMP
163 	smp_send_stop();
164 #endif
165 	printk(KERN_EMERG "System Halted, OK to turn off power\n");
166 	local_irq_disable();
167 	while (1) ;
168 }
169 
170 
171 #ifdef CONFIG_TAU
172 extern u32 cpu_temp(unsigned long cpu);
173 extern u32 cpu_temp_both(unsigned long cpu);
174 #endif /* CONFIG_TAU */
175 
176 #ifdef CONFIG_SMP
177 DEFINE_PER_CPU(unsigned int, cpu_pvr);
178 #endif
179 
180 static void show_cpuinfo_summary(struct seq_file *m)
181 {
182 	struct device_node *root;
183 	const char *model = NULL;
184 #if defined(CONFIG_SMP) && defined(CONFIG_PPC32)
185 	unsigned long bogosum = 0;
186 	int i;
187 	for_each_online_cpu(i)
188 		bogosum += loops_per_jiffy;
189 	seq_printf(m, "total bogomips\t: %lu.%02lu\n",
190 		   bogosum/(500000/HZ), bogosum/(5000/HZ) % 100);
191 #endif /* CONFIG_SMP && CONFIG_PPC32 */
192 	seq_printf(m, "timebase\t: %lu\n", ppc_tb_freq);
193 	if (ppc_md.name)
194 		seq_printf(m, "platform\t: %s\n", ppc_md.name);
195 	root = of_find_node_by_path("/");
196 	if (root)
197 		model = of_get_property(root, "model", NULL);
198 	if (model)
199 		seq_printf(m, "model\t\t: %s\n", model);
200 	of_node_put(root);
201 
202 	if (ppc_md.show_cpuinfo != NULL)
203 		ppc_md.show_cpuinfo(m);
204 
205 #ifdef CONFIG_PPC32
206 	/* Display the amount of memory */
207 	seq_printf(m, "Memory\t\t: %d MB\n",
208 		   (unsigned int)(total_memory / (1024 * 1024)));
209 #endif
210 }
211 
212 static int show_cpuinfo(struct seq_file *m, void *v)
213 {
214 	unsigned long cpu_id = (unsigned long)v - 1;
215 	unsigned int pvr;
216 	unsigned long proc_freq;
217 	unsigned short maj;
218 	unsigned short min;
219 
220 	/* We only show online cpus: disable preempt (overzealous, I
221 	 * knew) to prevent cpu going down. */
222 	preempt_disable();
223 	if (!cpu_online(cpu_id)) {
224 		preempt_enable();
225 		return 0;
226 	}
227 
228 #ifdef CONFIG_SMP
229 	pvr = per_cpu(cpu_pvr, cpu_id);
230 #else
231 	pvr = mfspr(SPRN_PVR);
232 #endif
233 	maj = (pvr >> 8) & 0xFF;
234 	min = pvr & 0xFF;
235 
236 	seq_printf(m, "processor\t: %lu\n", cpu_id);
237 	seq_printf(m, "cpu\t\t: ");
238 
239 	if (cur_cpu_spec->pvr_mask)
240 		seq_printf(m, "%s", cur_cpu_spec->cpu_name);
241 	else
242 		seq_printf(m, "unknown (%08x)", pvr);
243 
244 #ifdef CONFIG_ALTIVEC
245 	if (cpu_has_feature(CPU_FTR_ALTIVEC))
246 		seq_printf(m, ", altivec supported");
247 #endif /* CONFIG_ALTIVEC */
248 
249 	seq_printf(m, "\n");
250 
251 #ifdef CONFIG_TAU
252 	if (cur_cpu_spec->cpu_features & CPU_FTR_TAU) {
253 #ifdef CONFIG_TAU_AVERAGE
254 		/* more straightforward, but potentially misleading */
255 		seq_printf(m,  "temperature \t: %u C (uncalibrated)\n",
256 			   cpu_temp(cpu_id));
257 #else
258 		/* show the actual temp sensor range */
259 		u32 temp;
260 		temp = cpu_temp_both(cpu_id);
261 		seq_printf(m, "temperature \t: %u-%u C (uncalibrated)\n",
262 			   temp & 0xff, temp >> 16);
263 #endif
264 	}
265 #endif /* CONFIG_TAU */
266 
267 	/*
268 	 * Platforms that have variable clock rates, should implement
269 	 * the method ppc_md.get_proc_freq() that reports the clock
270 	 * rate of a given cpu. The rest can use ppc_proc_freq to
271 	 * report the clock rate that is same across all cpus.
272 	 */
273 	if (ppc_md.get_proc_freq)
274 		proc_freq = ppc_md.get_proc_freq(cpu_id);
275 	else
276 		proc_freq = ppc_proc_freq;
277 
278 	if (proc_freq)
279 		seq_printf(m, "clock\t\t: %lu.%06luMHz\n",
280 			   proc_freq / 1000000, proc_freq % 1000000);
281 
282 	if (ppc_md.show_percpuinfo != NULL)
283 		ppc_md.show_percpuinfo(m, cpu_id);
284 
285 	/* If we are a Freescale core do a simple check so
286 	 * we dont have to keep adding cases in the future */
287 	if (PVR_VER(pvr) & 0x8000) {
288 		switch (PVR_VER(pvr)) {
289 		case 0x8000:	/* 7441/7450/7451, Voyager */
290 		case 0x8001:	/* 7445/7455, Apollo 6 */
291 		case 0x8002:	/* 7447/7457, Apollo 7 */
292 		case 0x8003:	/* 7447A, Apollo 7 PM */
293 		case 0x8004:	/* 7448, Apollo 8 */
294 		case 0x800c:	/* 7410, Nitro */
295 			maj = ((pvr >> 8) & 0xF);
296 			min = PVR_MIN(pvr);
297 			break;
298 		default:	/* e500/book-e */
299 			maj = PVR_MAJ(pvr);
300 			min = PVR_MIN(pvr);
301 			break;
302 		}
303 	} else {
304 		switch (PVR_VER(pvr)) {
305 			case 0x0020:	/* 403 family */
306 				maj = PVR_MAJ(pvr) + 1;
307 				min = PVR_MIN(pvr);
308 				break;
309 			case 0x1008:	/* 740P/750P ?? */
310 				maj = ((pvr >> 8) & 0xFF) - 1;
311 				min = pvr & 0xFF;
312 				break;
313 			default:
314 				maj = (pvr >> 8) & 0xFF;
315 				min = pvr & 0xFF;
316 				break;
317 		}
318 	}
319 
320 	seq_printf(m, "revision\t: %hd.%hd (pvr %04x %04x)\n",
321 		   maj, min, PVR_VER(pvr), PVR_REV(pvr));
322 
323 #ifdef CONFIG_PPC32
324 	seq_printf(m, "bogomips\t: %lu.%02lu\n",
325 		   loops_per_jiffy / (500000/HZ),
326 		   (loops_per_jiffy / (5000/HZ)) % 100);
327 #endif
328 
329 #ifdef CONFIG_SMP
330 	seq_printf(m, "\n");
331 #endif
332 
333 	preempt_enable();
334 
335 	/* If this is the last cpu, print the summary */
336 	if (cpumask_next(cpu_id, cpu_online_mask) >= nr_cpu_ids)
337 		show_cpuinfo_summary(m);
338 
339 	return 0;
340 }
341 
342 static void *c_start(struct seq_file *m, loff_t *pos)
343 {
344 	if (*pos == 0)	/* just in case, cpu 0 is not the first */
345 		*pos = cpumask_first(cpu_online_mask);
346 	else
347 		*pos = cpumask_next(*pos - 1, cpu_online_mask);
348 	if ((*pos) < nr_cpu_ids)
349 		return (void *)(unsigned long)(*pos + 1);
350 	return NULL;
351 }
352 
353 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
354 {
355 	(*pos)++;
356 	return c_start(m, pos);
357 }
358 
359 static void c_stop(struct seq_file *m, void *v)
360 {
361 }
362 
363 const struct seq_operations cpuinfo_op = {
364 	.start =c_start,
365 	.next =	c_next,
366 	.stop =	c_stop,
367 	.show =	show_cpuinfo,
368 };
369 
370 void __init check_for_initrd(void)
371 {
372 #ifdef CONFIG_BLK_DEV_INITRD
373 	DBG(" -> check_for_initrd()  initrd_start=0x%lx  initrd_end=0x%lx\n",
374 	    initrd_start, initrd_end);
375 
376 	/* If we were passed an initrd, set the ROOT_DEV properly if the values
377 	 * look sensible. If not, clear initrd reference.
378 	 */
379 	if (is_kernel_addr(initrd_start) && is_kernel_addr(initrd_end) &&
380 	    initrd_end > initrd_start)
381 		ROOT_DEV = Root_RAM0;
382 	else
383 		initrd_start = initrd_end = 0;
384 
385 	if (initrd_start)
386 		pr_info("Found initrd at 0x%lx:0x%lx\n", initrd_start, initrd_end);
387 
388 	DBG(" <- check_for_initrd()\n");
389 #endif /* CONFIG_BLK_DEV_INITRD */
390 }
391 
392 #ifdef CONFIG_SMP
393 
394 int threads_per_core, threads_per_subcore, threads_shift;
395 cpumask_t threads_core_mask;
396 EXPORT_SYMBOL_GPL(threads_per_core);
397 EXPORT_SYMBOL_GPL(threads_per_subcore);
398 EXPORT_SYMBOL_GPL(threads_shift);
399 EXPORT_SYMBOL_GPL(threads_core_mask);
400 
401 static void __init cpu_init_thread_core_maps(int tpc)
402 {
403 	int i;
404 
405 	threads_per_core = tpc;
406 	threads_per_subcore = tpc;
407 	cpumask_clear(&threads_core_mask);
408 
409 	/* This implementation only supports power of 2 number of threads
410 	 * for simplicity and performance
411 	 */
412 	threads_shift = ilog2(tpc);
413 	BUG_ON(tpc != (1 << threads_shift));
414 
415 	for (i = 0; i < tpc; i++)
416 		cpumask_set_cpu(i, &threads_core_mask);
417 
418 	printk(KERN_INFO "CPU maps initialized for %d thread%s per core\n",
419 	       tpc, tpc > 1 ? "s" : "");
420 	printk(KERN_DEBUG " (thread shift is %d)\n", threads_shift);
421 }
422 
423 
424 /**
425  * setup_cpu_maps - initialize the following cpu maps:
426  *                  cpu_possible_mask
427  *                  cpu_present_mask
428  *
429  * Having the possible map set up early allows us to restrict allocations
430  * of things like irqstacks to nr_cpu_ids rather than NR_CPUS.
431  *
432  * We do not initialize the online map here; cpus set their own bits in
433  * cpu_online_mask as they come up.
434  *
435  * This function is valid only for Open Firmware systems.  finish_device_tree
436  * must be called before using this.
437  *
438  * While we're here, we may as well set the "physical" cpu ids in the paca.
439  *
440  * NOTE: This must match the parsing done in early_init_dt_scan_cpus.
441  */
442 void __init smp_setup_cpu_maps(void)
443 {
444 	struct device_node *dn = NULL;
445 	int cpu = 0;
446 	int nthreads = 1;
447 
448 	DBG("smp_setup_cpu_maps()\n");
449 
450 	while ((dn = of_find_node_by_type(dn, "cpu")) && cpu < nr_cpu_ids) {
451 		const __be32 *intserv;
452 		__be32 cpu_be;
453 		int j, len;
454 
455 		DBG("  * %s...\n", dn->full_name);
456 
457 		intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s",
458 				&len);
459 		if (intserv) {
460 			DBG("    ibm,ppc-interrupt-server#s -> %d threads\n",
461 			    nthreads);
462 		} else {
463 			DBG("    no ibm,ppc-interrupt-server#s -> 1 thread\n");
464 			intserv = of_get_property(dn, "reg", &len);
465 			if (!intserv) {
466 				cpu_be = cpu_to_be32(cpu);
467 				intserv = &cpu_be;	/* assume logical == phys */
468 				len = 4;
469 			}
470 		}
471 
472 		nthreads = len / sizeof(int);
473 
474 		for (j = 0; j < nthreads && cpu < nr_cpu_ids; j++) {
475 			bool avail;
476 
477 			DBG("    thread %d -> cpu %d (hard id %d)\n",
478 			    j, cpu, be32_to_cpu(intserv[j]));
479 
480 			avail = of_device_is_available(dn);
481 			if (!avail)
482 				avail = !of_property_match_string(dn,
483 						"enable-method", "spin-table");
484 
485 			set_cpu_present(cpu, avail);
486 			set_hard_smp_processor_id(cpu, be32_to_cpu(intserv[j]));
487 			set_cpu_possible(cpu, true);
488 			cpu++;
489 		}
490 	}
491 
492 	/* If no SMT supported, nthreads is forced to 1 */
493 	if (!cpu_has_feature(CPU_FTR_SMT)) {
494 		DBG("  SMT disabled ! nthreads forced to 1\n");
495 		nthreads = 1;
496 	}
497 
498 #ifdef CONFIG_PPC64
499 	/*
500 	 * On pSeries LPAR, we need to know how many cpus
501 	 * could possibly be added to this partition.
502 	 */
503 	if (machine_is(pseries) && firmware_has_feature(FW_FEATURE_LPAR) &&
504 	    (dn = of_find_node_by_path("/rtas"))) {
505 		int num_addr_cell, num_size_cell, maxcpus;
506 		const __be32 *ireg;
507 
508 		num_addr_cell = of_n_addr_cells(dn);
509 		num_size_cell = of_n_size_cells(dn);
510 
511 		ireg = of_get_property(dn, "ibm,lrdr-capacity", NULL);
512 
513 		if (!ireg)
514 			goto out;
515 
516 		maxcpus = be32_to_cpup(ireg + num_addr_cell + num_size_cell);
517 
518 		/* Double maxcpus for processors which have SMT capability */
519 		if (cpu_has_feature(CPU_FTR_SMT))
520 			maxcpus *= nthreads;
521 
522 		if (maxcpus > nr_cpu_ids) {
523 			printk(KERN_WARNING
524 			       "Partition configured for %d cpus, "
525 			       "operating system maximum is %d.\n",
526 			       maxcpus, nr_cpu_ids);
527 			maxcpus = nr_cpu_ids;
528 		} else
529 			printk(KERN_INFO "Partition configured for %d cpus.\n",
530 			       maxcpus);
531 
532 		for (cpu = 0; cpu < maxcpus; cpu++)
533 			set_cpu_possible(cpu, true);
534 	out:
535 		of_node_put(dn);
536 	}
537 	vdso_data->processorCount = num_present_cpus();
538 #endif /* CONFIG_PPC64 */
539 
540         /* Initialize CPU <=> thread mapping/
541 	 *
542 	 * WARNING: We assume that the number of threads is the same for
543 	 * every CPU in the system. If that is not the case, then some code
544 	 * here will have to be reworked
545 	 */
546 	cpu_init_thread_core_maps(nthreads);
547 
548 	/* Now that possible cpus are set, set nr_cpu_ids for later use */
549 	setup_nr_cpu_ids();
550 
551 	free_unused_pacas();
552 }
553 #endif /* CONFIG_SMP */
554 
555 #ifdef CONFIG_PCSPKR_PLATFORM
556 static __init int add_pcspkr(void)
557 {
558 	struct device_node *np;
559 	struct platform_device *pd;
560 	int ret;
561 
562 	np = of_find_compatible_node(NULL, NULL, "pnpPNP,100");
563 	of_node_put(np);
564 	if (!np)
565 		return -ENODEV;
566 
567 	pd = platform_device_alloc("pcspkr", -1);
568 	if (!pd)
569 		return -ENOMEM;
570 
571 	ret = platform_device_add(pd);
572 	if (ret)
573 		platform_device_put(pd);
574 
575 	return ret;
576 }
577 device_initcall(add_pcspkr);
578 #endif	/* CONFIG_PCSPKR_PLATFORM */
579 
580 void probe_machine(void)
581 {
582 	extern struct machdep_calls __machine_desc_start;
583 	extern struct machdep_calls __machine_desc_end;
584 
585 	/*
586 	 * Iterate all ppc_md structures until we find the proper
587 	 * one for the current machine type
588 	 */
589 	DBG("Probing machine type ...\n");
590 
591 	for (machine_id = &__machine_desc_start;
592 	     machine_id < &__machine_desc_end;
593 	     machine_id++) {
594 		DBG("  %s ...", machine_id->name);
595 		memcpy(&ppc_md, machine_id, sizeof(struct machdep_calls));
596 		if (ppc_md.probe()) {
597 			DBG(" match !\n");
598 			break;
599 		}
600 		DBG("\n");
601 	}
602 	/* What can we do if we didn't find ? */
603 	if (machine_id >= &__machine_desc_end) {
604 		DBG("No suitable machine found !\n");
605 		for (;;);
606 	}
607 
608 	printk(KERN_INFO "Using %s machine description\n", ppc_md.name);
609 }
610 
611 /* Match a class of boards, not a specific device configuration. */
612 int check_legacy_ioport(unsigned long base_port)
613 {
614 	struct device_node *parent, *np = NULL;
615 	int ret = -ENODEV;
616 
617 	switch(base_port) {
618 	case I8042_DATA_REG:
619 		if (!(np = of_find_compatible_node(NULL, NULL, "pnpPNP,303")))
620 			np = of_find_compatible_node(NULL, NULL, "pnpPNP,f03");
621 		if (np) {
622 			parent = of_get_parent(np);
623 
624 			of_i8042_kbd_irq = irq_of_parse_and_map(parent, 0);
625 			if (!of_i8042_kbd_irq)
626 				of_i8042_kbd_irq = 1;
627 
628 			of_i8042_aux_irq = irq_of_parse_and_map(parent, 1);
629 			if (!of_i8042_aux_irq)
630 				of_i8042_aux_irq = 12;
631 
632 			of_node_put(np);
633 			np = parent;
634 			break;
635 		}
636 		np = of_find_node_by_type(NULL, "8042");
637 		/* Pegasos has no device_type on its 8042 node, look for the
638 		 * name instead */
639 		if (!np)
640 			np = of_find_node_by_name(NULL, "8042");
641 		if (np) {
642 			of_i8042_kbd_irq = 1;
643 			of_i8042_aux_irq = 12;
644 		}
645 		break;
646 	case FDC_BASE: /* FDC1 */
647 		np = of_find_node_by_type(NULL, "fdc");
648 		break;
649 	default:
650 		/* ipmi is supposed to fail here */
651 		break;
652 	}
653 	if (!np)
654 		return ret;
655 	parent = of_get_parent(np);
656 	if (parent) {
657 		if (strcmp(parent->type, "isa") == 0)
658 			ret = 0;
659 		of_node_put(parent);
660 	}
661 	of_node_put(np);
662 	return ret;
663 }
664 EXPORT_SYMBOL(check_legacy_ioport);
665 
666 static int ppc_panic_event(struct notifier_block *this,
667                              unsigned long event, void *ptr)
668 {
669 	/*
670 	 * If firmware-assisted dump has been registered then trigger
671 	 * firmware-assisted dump and let firmware handle everything else.
672 	 */
673 	crash_fadump(NULL, ptr);
674 	ppc_md.panic(ptr);  /* May not return */
675 	return NOTIFY_DONE;
676 }
677 
678 static struct notifier_block ppc_panic_block = {
679 	.notifier_call = ppc_panic_event,
680 	.priority = INT_MIN /* may not return; must be done last */
681 };
682 
683 void __init setup_panic(void)
684 {
685 	atomic_notifier_chain_register(&panic_notifier_list, &ppc_panic_block);
686 }
687 
688 #ifdef CONFIG_CHECK_CACHE_COHERENCY
689 /*
690  * For platforms that have configurable cache-coherency.  This function
691  * checks that the cache coherency setting of the kernel matches the setting
692  * left by the firmware, as indicated in the device tree.  Since a mismatch
693  * will eventually result in DMA failures, we print * and error and call
694  * BUG() in that case.
695  */
696 
697 #ifdef CONFIG_NOT_COHERENT_CACHE
698 #define KERNEL_COHERENCY	0
699 #else
700 #define KERNEL_COHERENCY	1
701 #endif
702 
703 static int __init check_cache_coherency(void)
704 {
705 	struct device_node *np;
706 	const void *prop;
707 	int devtree_coherency;
708 
709 	np = of_find_node_by_path("/");
710 	prop = of_get_property(np, "coherency-off", NULL);
711 	of_node_put(np);
712 
713 	devtree_coherency = prop ? 0 : 1;
714 
715 	if (devtree_coherency != KERNEL_COHERENCY) {
716 		printk(KERN_ERR
717 			"kernel coherency:%s != device tree_coherency:%s\n",
718 			KERNEL_COHERENCY ? "on" : "off",
719 			devtree_coherency ? "on" : "off");
720 		BUG();
721 	}
722 
723 	return 0;
724 }
725 
726 late_initcall(check_cache_coherency);
727 #endif /* CONFIG_CHECK_CACHE_COHERENCY */
728 
729 #ifdef CONFIG_DEBUG_FS
730 struct dentry *powerpc_debugfs_root;
731 EXPORT_SYMBOL(powerpc_debugfs_root);
732 
733 static int powerpc_debugfs_init(void)
734 {
735 	powerpc_debugfs_root = debugfs_create_dir("powerpc", NULL);
736 
737 	return powerpc_debugfs_root == NULL;
738 }
739 arch_initcall(powerpc_debugfs_init);
740 #endif
741 
742 void ppc_printk_progress(char *s, unsigned short hex)
743 {
744 	pr_info("%s\n", s);
745 }
746 
747 void arch_setup_pdev_archdata(struct platform_device *pdev)
748 {
749 	pdev->archdata.dma_mask = DMA_BIT_MASK(32);
750 	pdev->dev.dma_mask = &pdev->archdata.dma_mask;
751  	set_dma_ops(&pdev->dev, &dma_direct_ops);
752 }
753