summaryrefslogtreecommitdiffstats
path: root/arch/powerpc/kernel/setup-common.c
blob: 70decd8068ca2a7802ca6c77f9b4ddf24089a801 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
/*
 * Common boot and setup code for both 32-bit and 64-bit.
 * Extracted from arch/powerpc/kernel/setup_64.c.
 *
 * Copyright (C) 2001 PPC64 Team, IBM Corp
 *
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 */

#undef DEBUG

#include <linux/module.h>
#include <linux/string.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/reboot.h>
#include <linux/delay.h>
#include <linux/initrd.h>
#include <linux/platform_device.h>
#include <linux/seq_file.h>
#include <linux/ioport.h>
#include <linux/console.h>
#include <linux/screen_info.h>
#include <linux/root_dev.h>
#include <linux/notifier.h>
#include <linux/cpu.h>
#include <linux/unistd.h>
#include <linux/serial.h>
#include <linux/serial_8250.h>
#include <linux/debugfs.h>
#include <linux/percpu.h>
#include <linux/memblock.h>
#include <linux/of_platform.h>
#include <asm/io.h>
#include <asm/paca.h>
#include <asm/prom.h>
#include <asm/processor.h>
#include <asm/vdso_datapage.h>
#include <asm/pgtable.h>
#include <asm/smp.h>
#include <asm/elf.h>
#include <asm/machdep.h>
#include <asm/time.h>
#include <asm/cputable.h>
#include <asm/sections.h>
#include <asm/firmware.h>
#include <asm/btext.h>
#include <asm/nvram.h>
#include <asm/setup.h>
#include <asm/system.h>
#include <asm/rtas.h>
#include <asm/iommu.h>
#include <asm/serial.h>
#include <asm/cache.h>
#include <asm/page.h>
#include <asm/mmu.h>
#include <asm/xmon.h>
#include <asm/cputhreads.h>
#include <mm/mmu_decl.h>

#include "setup.h"

#ifdef DEBUG
#include <asm/udbg.h>
#define DBG(fmt...) udbg_printf(fmt)
#else
#define DBG(fmt...)
#endif

/* The main machine-dep calls structure
 */
struct machdep_calls ppc_md;
EXPORT_SYMBOL(ppc_md);
struct machdep_calls *machine_id;
EXPORT_SYMBOL(machine_id);

unsigned long klimit = (unsigned long) _end;

char cmd_line[COMMAND_LINE_SIZE];

/*
 * This still seems to be needed... -- paulus
 */ 
struct screen_info screen_info = {
	.orig_x = 0,
	.orig_y = 25,
	.orig_video_cols = 80,
	.orig_video_lines = 25,
	.orig_video_isVGA = 1,
	.orig_video_points = 16
};

/* Variables required to store legacy IO irq routing */
int of_i8042_kbd_irq;
int of_i8042_aux_irq;

#ifdef __DO_IRQ_CANON
/* XXX should go elsewhere eventually */
int ppc_do_canonicalize_irqs;
EXPORT_SYMBOL(ppc_do_canonicalize_irqs);
#endif

/* also used by kexec */
void machine_shutdown(void)
{
	if (ppc_md.machine_shutdown)
		ppc_md.machine_shutdown();
}

void machine_restart(char *cmd)
{
	machine_shutdown();
	if (ppc_md.restart)
		ppc_md.restart(cmd);
#ifdef CONFIG_SMP
	smp_send_stop();
#endif
	printk(KERN_EMERG "System Halted, OK to turn off power\n");
	local_irq_disable();
	while (1) ;
}

void machine_power_off(void)
{
	machine_shutdown();
	if (ppc_md.power_off)
		ppc_md.power_off();
#ifdef CONFIG_SMP
	smp_send_stop();
#endif
	printk(KERN_EMERG "System Halted, OK to turn off power\n");
	local_irq_disable();
	while (1) ;
}
/* Used by the G5 thermal driver */
EXPORT_SYMBOL_GPL(machine_power_off);

void (*pm_power_off)(void) = machine_power_off;
EXPORT_SYMBOL_GPL(pm_power_off);

void machine_halt(void)
{
	machine_shutdown();
	if (ppc_md.halt)
		ppc_md.halt();
#ifdef CONFIG_SMP
	smp_send_stop();
#endif
	printk(KERN_EMERG "System Halted, OK to turn off power\n");
	local_irq_disable();
	while (1) ;
}


#ifdef CONFIG_TAU
extern u32 cpu_temp(unsigned long cpu);
extern u32 cpu_temp_both(unsigned long cpu);
#endif /* CONFIG_TAU */

#ifdef CONFIG_SMP
DEFINE_PER_CPU(unsigned int, cpu_pvr);
#endif

static void show_cpuinfo_summary(struct seq_file *m)
{
	struct device_node *root;
	const char *model = NULL;
#if defined(CONFIG_SMP) && defined(CONFIG_PPC32)
	unsigned long bogosum = 0;
	int i;
	for_each_online_cpu(i)
		bogosum += loops_per_jiffy;
	seq_printf(m, "total bogomips\t: %lu.%02lu\n",
		   bogosum/(500000/HZ), bogosum/(5000/HZ) % 100);
#endif /* CONFIG_SMP && CONFIG_PPC32 */
	seq_printf(m, "timebase\t: %lu\n", ppc_tb_freq);
	if (ppc_md.name)
		seq_printf(m, "platform\t: %s\n", ppc_md.name);
	root = of_find_node_by_path("/");
	if (root)
		model = of_get_property(root, "model", NULL);
	if (model)
		seq_printf(m, "model\t\t: %s\n", model);
	of_node_put(root);

	if (ppc_md.show_cpuinfo != NULL)
		ppc_md.show_cpuinfo(m);

#ifdef CONFIG_PPC32
	/* Display the amount of memory */
	seq_printf(m, "Memory\t\t: %d MB\n",
		   (unsigned int)(total_memory / (1024 * 1024)));
#endif
}

static int show_cpuinfo(struct seq_file *m, void *v)
{
	unsigned long cpu_id = (unsigned long)v - 1;
	unsigned int pvr;
	unsigned short maj;
	unsigned short min;

	/* We only show online cpus: disable preempt (overzealous, I
	 * knew) to prevent cpu going down. */
	preempt_disable();
	if (!cpu_online(cpu_id)) {
		preempt_enable();
		return 0;
	}

#ifdef CONFIG_SMP
	pvr = per_cpu(cpu_pvr, cpu_id);
#else
	pvr = mfspr(SPRN_PVR);
#endif
	maj = (pvr >> 8) & 0xFF;
	min = pvr & 0xFF;

	seq_printf(m, "processor\t: %lu\n", cpu_id);
	seq_printf(m, "cpu\t\t: ");

	if (cur_cpu_spec->pvr_mask)
		seq_printf(m, "%s", cur_cpu_spec->cpu_name);
	else
		seq_printf(m, "unknown (%08x)", pvr);

#ifdef CONFIG_ALTIVEC
	if (cpu_has_feature(CPU_FTR_ALTIVEC))
		seq_printf(m, ", altivec supported");
#endif /* CONFIG_ALTIVEC */

	seq_printf(m, "\n");

#ifdef CONFIG_TAU
	if (cur_cpu_spec->cpu_features & CPU_FTR_TAU) {
#ifdef CONFIG_TAU_AVERAGE
		/* more straightforward, but potentially misleading */
		seq_printf(m,  "temperature \t: %u C (uncalibrated)\n",
			   cpu_temp(cpu_id));
#else
		/* show the actual temp sensor range */
		u32 temp;
		temp = cpu_temp_both(cpu_id);
		seq_printf(m, "temperature \t: %u-%u C (uncalibrated)\n",
			   temp & 0xff, temp >> 16);
#endif
	}
#endif /* CONFIG_TAU */

	/*
	 * Assume here that all clock rates are the same in a
	 * smp system.  -- Cort
	 */
	if (ppc_proc_freq)
		seq_printf(m, "clock\t\t: %lu.%06luMHz\n",
			   ppc_proc_freq / 1000000, ppc_proc_freq % 1000000);

	if (ppc_md.show_percpuinfo != NULL)
		ppc_md.show_percpuinfo(m, cpu_id);

	/* If we are a Freescale core do a simple check so
	 * we dont have to keep adding cases in the future */
	if (PVR_VER(pvr) & 0x8000) {
		switch (PVR_VER(pvr)) {
		case 0x8000:	/* 7441/7450/7451, Voyager */
		case 0x8001:	/* 7445/7455, Apollo 6 */
		case 0x8002:	/* 7447/7457, Apollo 7 */
		case 0x8003:	/* 7447A, Apollo 7 PM */
		case 0x8004:	/* 7448, Apollo 8 */
		case 0x800c:	/* 7410, Nitro */
			maj = ((pvr >> 8) & 0xF);
			min = PVR_MIN(pvr);
			break;
		default:	/* e500/book-e */
			maj = PVR_MAJ(pvr);
			min = PVR_MIN(pvr);
			break;
		}
	} else {
		switch (PVR_VER(pvr)) {
			case 0x0020:	/* 403 family */
				maj = PVR_MAJ(pvr) + 1;
				min = PVR_MIN(pvr);
				break;
			case 0x1008:	/* 740P/750P ?? */
				maj = ((pvr >> 8) & 0xFF) - 1;
				min = pvr & 0xFF;
				break;
			default:
				maj = (pvr >> 8) & 0xFF;
				min = pvr & 0xFF;
				break;
		}
	}

	seq_printf(m, "revision\t: %hd.%hd (pvr %04x %04x)\n",
		   maj, min, PVR_VER(pvr), PVR_REV(pvr));

#ifdef CONFIG_PPC32
	seq_printf(m, "bogomips\t: %lu.%02lu\n",
		   loops_per_jiffy / (500000/HZ),
		   (loops_per_jiffy / (5000/HZ)) % 100);
#endif

#ifdef CONFIG_SMP
	seq_printf(m, "\n");
#endif

	preempt_enable();

	/* If this is the last cpu, print the summary */
	if (cpumask_next(cpu_id, cpu_online_mask) >= nr_cpu_ids)
		show_cpuinfo_summary(m);

	return 0;
}

static void *c_start(struct seq_file *m, loff_t *pos)
{
	if (*pos == 0)	/* just in case, cpu 0 is not the first */
		*pos = cpumask_first(cpu_online_mask);
	else
		*pos = cpumask_next(*pos - 1, cpu_online_mask);
	if ((*pos) < nr_cpu_ids)
		return (void *)(unsigned long)(*pos + 1);
	return NULL;
}

static void *c_next(struct seq_file *m, void *v, loff_t *pos)
{
	(*pos)++;
	return c_start(m, pos);
}

static void c_stop(struct seq_file *m, void *v)
{
}

const struct seq_operations cpuinfo_op = {
	.start =c_start,
	.next =	c_next,
	.stop =	c_stop,
	.show =	show_cpuinfo,
};

void __init check_for_initrd(void)
{
#ifdef CONFIG_BLK_DEV_INITRD
	DBG(" -> check_for_initrd()  initrd_start=0x%lx  initrd_end=0x%lx\n",
	    initrd_start, initrd_end);

	/* If we were passed an initrd, set the ROOT_DEV properly if the values
	 * look sensible. If not, clear initrd reference.
	 */
	if (is_kernel_addr(initrd_start) && is_kernel_addr(initrd_end) &&
	    initrd_end > initrd_start)
		ROOT_DEV = Root_RAM0;
	else
		initrd_start = initrd_end = 0;

	if (initrd_start)
		printk("Found initrd at 0x%lx:0x%lx\n", initrd_start, initrd_end);

	DBG(" <- check_for_initrd()\n");
#endif /* CONFIG_BLK_DEV_INITRD */
}

#ifdef CONFIG_SMP

int threads_per_core, threads_shift;
cpumask_t threads_core_mask;

static void __init cpu_init_thread_core_maps(int tpc)
{
	int i;

	threads_per_core = tpc;
	threads_core_mask = CPU_MASK_NONE;

	/* This implementation only supports power of 2 number of threads
	 * for simplicity and performance
	 */
	threads_shift = ilog2(tpc);
	BUG_ON(tpc != (1 << threads_shift));

	for (i = 0; i < tpc; i++)
		cpu_set(i, threads_core_mask);

	printk(KERN_INFO "CPU maps initialized for %d thread%s per core\n",
	       tpc, tpc > 1 ? "s" : "");
	printk(KERN_DEBUG " (thread shift is %d)\n", threads_shift);
}


/**
 * setup_cpu_maps - initialize the following cpu maps:
 *                  cpu_possible_mask
 *                  cpu_present_mask
 *
 * Having the possible map set up early allows us to restrict allocations
 * of things like irqstacks to num_possible_cpus() rather than NR_CPUS.
 *
 * We do not initialize the online map here; cpus set their own bits in
 * cpu_online_mask as they come up.
 *
 * This function is valid only for Open Firmware systems.  finish_device_tree
 * must be called before using this.
 *
 * While we're here, we may as well set the "physical" cpu ids in the paca.
 *
 * NOTE: This must match the parsing done in early_init_dt_scan_cpus.
 */
void __init smp_setup_cpu_maps(void)
{
	struct device_node *dn = NULL;
	int cpu = 0;
	int nthreads = 1;

	DBG("smp_setup_cpu_maps()\n");

	while ((dn = of_find_node_by_type(dn, "cpu")) && cpu < NR_CPUS) {
		const int *intserv;
		int j, len;

		DBG("  * %s...\n", dn->full_name);

		intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s",
				&len);
		if (intserv) {
			nthreads = len / sizeof(int);
			DBG("    ibm,ppc-interrupt-server#s -> %d threads\n",
			    nthreads);
		} else {
			DBG("    no ibm,ppc-interrupt-server#s -> 1 thread\n");
			intserv = of_get_property(dn, "reg", NULL);
			if (!intserv)
				intserv = &cpu;	/* assume logical == phys */
		}

		for (j = 0; j < nthreads && cpu < NR_CPUS; j++) {
			DBG("    thread %d -> cpu %d (hard id %d)\n",
			    j, cpu, intserv[j]);
			set_cpu_present(cpu, true);
			set_hard_smp_processor_id(cpu, intserv[j]);
			set_cpu_possible(cpu, true);
			cpu++;
		}
	}

	/* If no SMT supported, nthreads is forced to 1 */
	if (!cpu_has_feature(CPU_FTR_SMT)) {
		DBG("  SMT disabled ! nthreads forced to 1\n");
		nthreads = 1;
	}

#ifdef CONFIG_PPC64
	/*
	 * On pSeries LPAR, we need to know how many cpus
	 * could possibly be added to this partition.
	 */
	if (machine_is(pseries) && firmware_has_feature(FW_FEATURE_LPAR) &&
	    (dn = of_find_node_by_path("/rtas"))) {
		int num_addr_cell, num_size_cell, maxcpus;
		const unsigned int *ireg;

		num_addr_cell = of_n_addr_cells(dn);
		num_size_cell = of_n_size_cells(dn);

		ireg = of_get_property(dn, "ibm,lrdr-capacity", NULL);

		if (!ireg)
			goto out;

		maxcpus = ireg[num_addr_cell + num_size_cell];

		/* Double maxcpus for processors which have SMT capability */
		if (cpu_has_feature(CPU_FTR_SMT))
			maxcpus *= nthreads;

		if (maxcpus > NR_CPUS) {
			printk(KERN_WARNING
			       "Partition configured for %d cpus, "
			       "operating system maximum is %d.\n",
			       maxcpus, NR_CPUS);
			maxcpus = NR_CPUS;
		} else
			printk(KERN_INFO "Partition configured for %d cpus.\n",
			       maxcpus);

		for (cpu = 0; cpu < maxcpus; cpu++)
			set_cpu_possible(cpu, true);
	out:
		of_node_put(dn);
	}
	vdso_data->processorCount = num_present_cpus();
#endif /* CONFIG_PPC64 */

        /* Initialize CPU <=> thread mapping/
	 *
	 * WARNING: We assume that the number of threads is the same for
	 * every CPU in the system. If that is not the case, then some code
	 * here will have to be reworked
	 */
	cpu_init_thread_core_maps(nthreads);

	free_unused_pacas();
}
#endif /* CONFIG_SMP */

#ifdef CONFIG_PCSPKR_PLATFORM
static __init int add_pcspkr(void)
{
	struct device_node *np;
	struct platform_device *pd;
	int ret;

	np = of_find_compatible_node(NULL, NULL, "pnpPNP,100");
	of_node_put(np);
	if (!np)
		return -ENODEV;

	pd = platform_device_alloc("pcspkr", -1);
	if (!pd)
		return -ENOMEM;

	ret = platform_device_add(pd);
	if (ret)
		platform_device_put(pd);

	return ret;
}
device_initcall(add_pcspkr);
#endif	/* CONFIG_PCSPKR_PLATFORM */

void probe_machine(void)
{
	extern struct machdep_calls __machine_desc_start;
	extern struct machdep_calls __machine_desc_end;

	/*
	 * Iterate all ppc_md structures until we find the proper
	 * one for the current machine type
	 */
	DBG("Probing machine type ...\n");

	for (machine_id = &__machine_desc_start;
	     machine_id < &__machine_desc_end;
	     machine_id++) {
		DBG("  %s ...", machine_id->name);
		memcpy(&ppc_md, machine_id, sizeof(struct machdep_calls));
		if (ppc_md.probe()) {
			DBG(" match !\n");
			break;
		}
		DBG("\n");
	}
	/* What can we do if we didn't find ? */
	if (machine_id >= &__machine_desc_end) {
		DBG("No suitable machine found !\n");
		for (;;);
	}

	printk(KERN_INFO "Using %s machine description\n", ppc_md.name);
}

/* Match a class of boards, not a specific device configuration. */
int check_legacy_ioport(unsigned long base_port)
{
	struct device_node *parent, *np = NULL;
	int ret = -ENODEV;

	switch(base_port) {
	case I8042_DATA_REG:
		if (!(np = of_find_compatible_node(NULL, NULL, "pnpPNP,303")))
			np = of_find_compatible_node(NULL, NULL, "pnpPNP,f03");
		if (np) {
			parent = of_get_parent(np);

			of_i8042_kbd_irq = irq_of_parse_and_map(parent, 0);
			if (!of_i8042_kbd_irq)
				of_i8042_kbd_irq = 1;

			of_i8042_aux_irq = irq_of_parse_and_map(parent, 1);
			if (!of_i8042_aux_irq)
				of_i8042_aux_irq = 12;

			of_node_put(np);
			np = parent;
			break;
		}
		np = of_find_node_by_type(NULL, "8042");
		/* Pegasos has no device_type on its 8042 node, look for the
		 * name instead */
		if (!np)
			np = of_find_node_by_name(NULL, "8042");
		break;
	case FDC_BASE: /* FDC1 */
		np = of_find_node_by_type(NULL, "fdc");
		break;
#ifdef CONFIG_PPC_PREP
	case _PIDXR:
	case _PNPWRP:
	case PNPBIOS_BASE:
		/* implement me */
#endif
	default:
		/* ipmi is supposed to fail here */
		break;
	}
	if (!np)
		return ret;
	parent = of_get_parent(np);
	if (parent) {
		if (strcmp(parent->type, "isa") == 0)
			ret = 0;
		of_node_put(parent);
	}
	of_node_put(np);
	return ret;
}
EXPORT_SYMBOL(check_legacy_ioport);

static int ppc_panic_event(struct notifier_block *this,
                             unsigned long event, void *ptr)
{
	ppc_md.panic(ptr);  /* May not return */
	return NOTIFY_DONE;
}

static struct notifier_block ppc_panic_block = {
	.notifier_call = ppc_panic_event,
	.priority = INT_MIN /* may not return; must be done last */
};

void __init setup_panic(void)
{
	atomic_notifier_chain_register(&panic_notifier_list, &ppc_panic_block);
}

#ifdef CONFIG_CHECK_CACHE_COHERENCY
/*
 * For platforms that have configurable cache-coherency.  This function
 * checks that the cache coherency setting of the kernel matches the setting
 * left by the firmware, as indicated in the device tree.  Since a mismatch
 * will eventually result in DMA failures, we print * and error and call
 * BUG() in that case.
 */

#ifdef CONFIG_NOT_COHERENT_CACHE
#define KERNEL_COHERENCY	0
#else
#define KERNEL_COHERENCY	1
#endif

static int __init check_cache_coherency(void)
{
	struct device_node *np;
	const void *prop;
	int devtree_coherency;

	np = of_find_node_by_path("/");
	prop = of_get_property(np, "coherency-off", NULL);
	of_node_put(np);

	devtree_coherency = prop ? 0 : 1;

	if (devtree_coherency != KERNEL_COHERENCY) {
		printk(KERN_ERR
			"kernel coherency:%s != device tree_coherency:%s\n",
			KERNEL_COHERENCY ? "on" : "off",
			devtree_coherency ? "on" : "off");
		BUG();
	}

	return 0;
}

late_initcall(check_cache_coherency);
#endif /* CONFIG_CHECK_CACHE_COHERENCY */

#ifdef CONFIG_DEBUG_FS
struct dentry *powerpc_debugfs_root;
EXPORT_SYMBOL(powerpc_debugfs_root);

static int powerpc_debugfs_init(void)
{
	powerpc_debugfs_root = debugfs_create_dir("powerpc", NULL);

	return powerpc_debugfs_root == NULL;
}
arch_initcall(powerpc_debugfs_init);
#endif

static int ppc_dflt_bus_notify(struct notifier_block *nb,
				unsigned long action, void *data)
{
	struct device *dev = data;

	/* We are only intereted in device addition */
	if (action != BUS_NOTIFY_ADD_DEVICE)
		return 0;

	set_dma_ops(dev, &dma_direct_ops);

	return NOTIFY_DONE;
}

static struct notifier_block ppc_dflt_plat_bus_notifier = {
	.notifier_call = ppc_dflt_bus_notify,
	.priority = INT_MAX,
};

static struct notifier_block ppc_dflt_of_bus_notifier = {
	.notifier_call = ppc_dflt_bus_notify,
	.priority = INT_MAX,
};

static int __init setup_bus_notifier(void)
{
	bus_register_notifier(&platform_bus_type, &ppc_dflt_plat_bus_notifier);
	bus_register_notifier(&of_platform_bus_type, &ppc_dflt_of_bus_notifier);

	return 0;
}

arch_initcall(setup_bus_notifier);
OpenPOWER on IntegriCloud