summaryrefslogtreecommitdiff
path: root/arch/powerpc/platforms/powernv/opal.c
blob: f343183add07c189d02b0701e284f72effd614fc (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
/*
 * PowerNV OPAL high level interfaces
 *
 * Copyright 2011 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/types.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
#include <linux/of_platform.h>
#include <linux/interrupt.h>
#include <linux/notifier.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/kobject.h>
#include <linux/delay.h>
#include <linux/memblock.h>
#include <asm/opal.h>
#include <asm/firmware.h>
#include <asm/mce.h>

#include "powernv.h"

/* /sys/firmware/opal */
struct kobject *opal_kobj;

struct opal {
	u64 base;
	u64 entry;
	u64 size;
} opal;

struct mcheck_recoverable_range {
	u64 start_addr;
	u64 end_addr;
	u64 recover_addr;
};

static struct mcheck_recoverable_range *mc_recoverable_range;
static int mc_recoverable_range_len;

struct device_node *opal_node;
static DEFINE_SPINLOCK(opal_write_lock);
extern u64 opal_mc_secondary_handler[];
static unsigned int *opal_irqs;
static unsigned int opal_irq_count;
static ATOMIC_NOTIFIER_HEAD(opal_notifier_head);
static struct atomic_notifier_head opal_msg_notifier_head[OPAL_MSG_TYPE_MAX];
static DEFINE_SPINLOCK(opal_notifier_lock);
static uint64_t last_notified_mask = 0x0ul;
static atomic_t opal_notifier_hold = ATOMIC_INIT(0);

int __init early_init_dt_scan_opal(unsigned long node,
				   const char *uname, int depth, void *data)
{
	const void *basep, *entryp, *sizep;
	int basesz, entrysz, runtimesz;

	if (depth != 1 || strcmp(uname, "ibm,opal") != 0)
		return 0;

	basep  = of_get_flat_dt_prop(node, "opal-base-address", &basesz);
	entryp = of_get_flat_dt_prop(node, "opal-entry-address", &entrysz);
	sizep = of_get_flat_dt_prop(node, "opal-runtime-size", &runtimesz);

	if (!basep || !entryp || !sizep)
		return 1;

	opal.base = of_read_number(basep, basesz/4);
	opal.entry = of_read_number(entryp, entrysz/4);
	opal.size = of_read_number(sizep, runtimesz/4);

	pr_debug("OPAL Base  = 0x%llx (basep=%p basesz=%d)\n",
		 opal.base, basep, basesz);
	pr_debug("OPAL Entry = 0x%llx (entryp=%p basesz=%d)\n",
		 opal.entry, entryp, entrysz);
	pr_debug("OPAL Entry = 0x%llx (sizep=%p runtimesz=%d)\n",
		 opal.size, sizep, runtimesz);

	powerpc_firmware_features |= FW_FEATURE_OPAL;
	if (of_flat_dt_is_compatible(node, "ibm,opal-v3")) {
		powerpc_firmware_features |= FW_FEATURE_OPALv2;
		powerpc_firmware_features |= FW_FEATURE_OPALv3;
		printk("OPAL V3 detected !\n");
	} else if (of_flat_dt_is_compatible(node, "ibm,opal-v2")) {
		powerpc_firmware_features |= FW_FEATURE_OPALv2;
		printk("OPAL V2 detected !\n");
	} else {
		printk("OPAL V1 detected !\n");
	}

	return 1;
}

int __init early_init_dt_scan_recoverable_ranges(unsigned long node,
				   const char *uname, int depth, void *data)
{
	int i, psize, size;
	const __be32 *prop;

	if (depth != 1 || strcmp(uname, "ibm,opal") != 0)
		return 0;

	prop = of_get_flat_dt_prop(node, "mcheck-recoverable-ranges", &psize);

	if (!prop)
		return 1;

	pr_debug("Found machine check recoverable ranges.\n");

	/*
	 * Calculate number of available entries.
	 *
	 * Each recoverable address range entry is (start address, len,
	 * recovery address), 2 cells each for start and recovery address,
	 * 1 cell for len, totalling 5 cells per entry.
	 */
	mc_recoverable_range_len = psize / (sizeof(*prop) * 5);

	/* Sanity check */
	if (!mc_recoverable_range_len)
		return 1;

	/* Size required to hold all the entries. */
	size = mc_recoverable_range_len *
			sizeof(struct mcheck_recoverable_range);

	/*
	 * Allocate a buffer to hold the MC recoverable ranges. We would be
	 * accessing them in real mode, hence it needs to be within
	 * RMO region.
	 */
	mc_recoverable_range =__va(memblock_alloc_base(size, __alignof__(u64),
							ppc64_rma_size));
	memset(mc_recoverable_range, 0, size);

	for (i = 0; i < mc_recoverable_range_len; i++) {
		mc_recoverable_range[i].start_addr =
					of_read_number(prop + (i * 5) + 0, 2);
		mc_recoverable_range[i].end_addr =
					mc_recoverable_range[i].start_addr +
					of_read_number(prop + (i * 5) + 2, 1);
		mc_recoverable_range[i].recover_addr =
					of_read_number(prop + (i * 5) + 3, 2);

		pr_debug("Machine check recoverable range: %llx..%llx: %llx\n",
				mc_recoverable_range[i].start_addr,
				mc_recoverable_range[i].end_addr,
				mc_recoverable_range[i].recover_addr);
	}
	return 1;
}

static int __init opal_register_exception_handlers(void)
{
#ifdef __BIG_ENDIAN__
	u64 glue;

	if (!(powerpc_firmware_features & FW_FEATURE_OPAL))
		return -ENODEV;

	/* Hookup some exception handlers except machine check. We use the
	 * fwnmi area at 0x7000 to provide the glue space to OPAL
	 */
	glue = 0x7000;
	opal_register_exception_handler(OPAL_HYPERVISOR_MAINTENANCE_HANDLER,
					0, glue);
	glue += 128;
	opal_register_exception_handler(OPAL_SOFTPATCH_HANDLER, 0, glue);
#endif

	return 0;
}

early_initcall(opal_register_exception_handlers);

int opal_notifier_register(struct notifier_block *nb)
{
	if (!nb) {
		pr_warning("%s: Invalid argument (%p)\n",
			   __func__, nb);
		return -EINVAL;
	}

	atomic_notifier_chain_register(&opal_notifier_head, nb);
	return 0;
}
EXPORT_SYMBOL_GPL(opal_notifier_register);

int opal_notifier_unregister(struct notifier_block *nb)
{
	if (!nb) {
		pr_warning("%s: Invalid argument (%p)\n",
			   __func__, nb);
		return -EINVAL;
	}

	atomic_notifier_chain_unregister(&opal_notifier_head, nb);
	return 0;
}
EXPORT_SYMBOL_GPL(opal_notifier_unregister);

static void opal_do_notifier(uint64_t events)
{
	unsigned long flags;
	uint64_t changed_mask;

	if (atomic_read(&opal_notifier_hold))
		return;

	spin_lock_irqsave(&opal_notifier_lock, flags);
	changed_mask = last_notified_mask ^ events;
	last_notified_mask = events;
	spin_unlock_irqrestore(&opal_notifier_lock, flags);

	/*
	 * We feed with the event bits and changed bits for
	 * enough information to the callback.
	 */
	atomic_notifier_call_chain(&opal_notifier_head,
				   events, (void *)changed_mask);
}

void opal_notifier_update_evt(uint64_t evt_mask,
			      uint64_t evt_val)
{
	unsigned long flags;

	spin_lock_irqsave(&opal_notifier_lock, flags);
	last_notified_mask &= ~evt_mask;
	last_notified_mask |= evt_val;
	spin_unlock_irqrestore(&opal_notifier_lock, flags);
}

void opal_notifier_enable(void)
{
	int64_t rc;
	__be64 evt = 0;

	atomic_set(&opal_notifier_hold, 0);

	/* Process pending events */
	rc = opal_poll_events(&evt);
	if (rc == OPAL_SUCCESS && evt)
		opal_do_notifier(be64_to_cpu(evt));
}

void opal_notifier_disable(void)
{
	atomic_set(&opal_notifier_hold, 1);
}

/*
 * Opal message notifier based on message type. Allow subscribers to get
 * notified for specific messgae type.
 */
int opal_message_notifier_register(enum OpalMessageType msg_type,
					struct notifier_block *nb)
{
	if (!nb) {
		pr_warning("%s: Invalid argument (%p)\n",
			   __func__, nb);
		return -EINVAL;
	}
	if (msg_type > OPAL_MSG_TYPE_MAX) {
		pr_warning("%s: Invalid message type argument (%d)\n",
			   __func__, msg_type);
		return -EINVAL;
	}
	return atomic_notifier_chain_register(
				&opal_msg_notifier_head[msg_type], nb);
}

static void opal_message_do_notify(uint32_t msg_type, void *msg)
{
	/* notify subscribers */
	atomic_notifier_call_chain(&opal_msg_notifier_head[msg_type],
					msg_type, msg);
}

static void opal_handle_message(void)
{
	s64 ret;
	/*
	 * TODO: pre-allocate a message buffer depending on opal-msg-size
	 * value in /proc/device-tree.
	 */
	static struct opal_msg msg;
	u32 type;

	ret = opal_get_msg(__pa(&msg), sizeof(msg));
	/* No opal message pending. */
	if (ret == OPAL_RESOURCE)
		return;

	/* check for errors. */
	if (ret) {
		pr_warning("%s: Failed to retrive opal message, err=%lld\n",
				__func__, ret);
		return;
	}

	type = be32_to_cpu(msg.msg_type);

	/* Sanity check */
	if (type > OPAL_MSG_TYPE_MAX) {
		pr_warning("%s: Unknown message type: %u\n", __func__, type);
		return;
	}
	opal_message_do_notify(type, (void *)&msg);
}

static int opal_message_notify(struct notifier_block *nb,
			  unsigned long events, void *change)
{
	if (events & OPAL_EVENT_MSG_PENDING)
		opal_handle_message();
	return 0;
}

static struct notifier_block opal_message_nb = {
	.notifier_call	= opal_message_notify,
	.next		= NULL,
	.priority	= 0,
};

static int __init opal_message_init(void)
{
	int ret, i;

	for (i = 0; i < OPAL_MSG_TYPE_MAX; i++)
		ATOMIC_INIT_NOTIFIER_HEAD(&opal_msg_notifier_head[i]);

	ret = opal_notifier_register(&opal_message_nb);
	if (ret) {
		pr_err("%s: Can't register OPAL event notifier (%d)\n",
		       __func__, ret);
		return ret;
	}
	return 0;
}
early_initcall(opal_message_init);

int opal_get_chars(uint32_t vtermno, char *buf, int count)
{
	s64 rc;
	__be64 evt, len;

	if (!opal.entry)
		return -ENODEV;
	opal_poll_events(&evt);
	if ((be64_to_cpu(evt) & OPAL_EVENT_CONSOLE_INPUT) == 0)
		return 0;
	len = cpu_to_be64(count);
	rc = opal_console_read(vtermno, &len, buf);
	if (rc == OPAL_SUCCESS)
		return be64_to_cpu(len);
	return 0;
}

int opal_put_chars(uint32_t vtermno, const char *data, int total_len)
{
	int written = 0;
	__be64 olen;
	s64 len, rc;
	unsigned long flags;
	__be64 evt;

	if (!opal.entry)
		return -ENODEV;

	/* We want put_chars to be atomic to avoid mangling of hvsi
	 * packets. To do that, we first test for room and return
	 * -EAGAIN if there isn't enough.
	 *
	 * Unfortunately, opal_console_write_buffer_space() doesn't
	 * appear to work on opal v1, so we just assume there is
	 * enough room and be done with it
	 */
	spin_lock_irqsave(&opal_write_lock, flags);
	if (firmware_has_feature(FW_FEATURE_OPALv2)) {
		rc = opal_console_write_buffer_space(vtermno, &olen);
		len = be64_to_cpu(olen);
		if (rc || len < total_len) {
			spin_unlock_irqrestore(&opal_write_lock, flags);
			/* Closed -> drop characters */
			if (rc)
				return total_len;
			opal_poll_events(NULL);
			return -EAGAIN;
		}
	}

	/* We still try to handle partial completions, though they
	 * should no longer happen.
	 */
	rc = OPAL_BUSY;
	while(total_len > 0 && (rc == OPAL_BUSY ||
				rc == OPAL_BUSY_EVENT || rc == OPAL_SUCCESS)) {
		olen = cpu_to_be64(total_len);
		rc = opal_console_write(vtermno, &olen, data);
		len = be64_to_cpu(olen);

		/* Closed or other error drop */
		if (rc != OPAL_SUCCESS && rc != OPAL_BUSY &&
		    rc != OPAL_BUSY_EVENT) {
			written = total_len;
			break;
		}
		if (rc == OPAL_SUCCESS) {
			total_len -= len;
			data += len;
			written += len;
		}
		/* This is a bit nasty but we need that for the console to
		 * flush when there aren't any interrupts. We will clean
		 * things a bit later to limit that to synchronous path
		 * such as the kernel console and xmon/udbg
		 */
		do
			opal_poll_events(&evt);
		while(rc == OPAL_SUCCESS &&
			(be64_to_cpu(evt) & OPAL_EVENT_CONSOLE_OUTPUT));
	}
	spin_unlock_irqrestore(&opal_write_lock, flags);
	return written;
}

static int opal_recover_mce(struct pt_regs *regs,
					struct machine_check_event *evt)
{
	int recovered = 0;
	uint64_t ea = get_mce_fault_addr(evt);

	if (!(regs->msr & MSR_RI)) {
		/* If MSR_RI isn't set, we cannot recover */
		recovered = 0;
	} else if (evt->disposition == MCE_DISPOSITION_RECOVERED) {
		/* Platform corrected itself */
		recovered = 1;
	} else if (ea && !is_kernel_addr(ea)) {
		/*
		 * Faulting address is not in kernel text. We should be fine.
		 * We need to find which process uses this address.
		 * For now, kill the task if we have received exception when
		 * in userspace.
		 *
		 * TODO: Queue up this address for hwpoisioning later.
		 */
		if (user_mode(regs) && !is_global_init(current)) {
			_exception(SIGBUS, regs, BUS_MCEERR_AR, regs->nip);
			recovered = 1;
		} else
			recovered = 0;
	} else if (user_mode(regs) && !is_global_init(current) &&
		evt->severity == MCE_SEV_ERROR_SYNC) {
		/*
		 * If we have received a synchronous error when in userspace
		 * kill the task.
		 */
		_exception(SIGBUS, regs, BUS_MCEERR_AR, regs->nip);
		recovered = 1;
	}
	return recovered;
}

int opal_machine_check(struct pt_regs *regs)
{
	struct machine_check_event evt;

	if (!get_mce_event(&evt, MCE_EVENT_RELEASE))
		return 0;

	/* Print things out */
	if (evt.version != MCE_V1) {
		pr_err("Machine Check Exception, Unknown event version %d !\n",
		       evt.version);
		return 0;
	}
	machine_check_print_event_info(&evt);

	if (opal_recover_mce(regs, &evt))
		return 1;
	return 0;
}

static uint64_t find_recovery_address(uint64_t nip)
{
	int i;

	for (i = 0; i < mc_recoverable_range_len; i++)
		if ((nip >= mc_recoverable_range[i].start_addr) &&
		    (nip < mc_recoverable_range[i].end_addr))
		    return mc_recoverable_range[i].recover_addr;
	return 0;
}

bool opal_mce_check_early_recovery(struct pt_regs *regs)
{
	uint64_t recover_addr = 0;

	if (!opal.base || !opal.size)
		goto out;

	if ((regs->nip >= opal.base) &&
			(regs->nip <= (opal.base + opal.size)))
		recover_addr = find_recovery_address(regs->nip);

	/*
	 * Setup regs->nip to rfi into fixup address.
	 */
	if (recover_addr)
		regs->nip = recover_addr;

out:
	return !!recover_addr;
}

static irqreturn_t opal_interrupt(int irq, void *data)
{
	__be64 events;

	opal_handle_interrupt(virq_to_hw(irq), &events);

	opal_do_notifier(be64_to_cpu(events));

	return IRQ_HANDLED;
}

static int opal_sysfs_init(void)
{
	opal_kobj = kobject_create_and_add("opal", firmware_kobj);
	if (!opal_kobj) {
		pr_warn("kobject_create_and_add opal failed\n");
		return -ENOMEM;
	}

	return 0;
}

static int __init opal_init(void)
{
	struct device_node *np, *consoles;
	const __be32 *irqs;
	int rc, i, irqlen;

	opal_node = of_find_node_by_path("/ibm,opal");
	if (!opal_node) {
		pr_warn("opal: Node not found\n");
		return -ENODEV;
	}

	/* Register OPAL consoles if any ports */
	if (firmware_has_feature(FW_FEATURE_OPALv2))
		consoles = of_find_node_by_path("/ibm,opal/consoles");
	else
		consoles = of_node_get(opal_node);
	if (consoles) {
		for_each_child_of_node(consoles, np) {
			if (strcmp(np->name, "serial"))
				continue;
			of_platform_device_create(np, NULL, NULL);
		}
		of_node_put(consoles);
	}

	/* Find all OPAL interrupts and request them */
	irqs = of_get_property(opal_node, "opal-interrupts", &irqlen);
	pr_debug("opal: Found %d interrupts reserved for OPAL\n",
		 irqs ? (irqlen / 4) : 0);
	opal_irq_count = irqlen / 4;
	opal_irqs = kzalloc(opal_irq_count * sizeof(unsigned int), GFP_KERNEL);
	for (i = 0; irqs && i < (irqlen / 4); i++, irqs++) {
		unsigned int hwirq = be32_to_cpup(irqs);
		unsigned int irq = irq_create_mapping(NULL, hwirq);
		if (irq == NO_IRQ) {
			pr_warning("opal: Failed to map irq 0x%x\n", hwirq);
			continue;
		}
		rc = request_irq(irq, opal_interrupt, 0, "opal", NULL);
		if (rc)
			pr_warning("opal: Error %d requesting irq %d"
				   " (0x%x)\n", rc, irq, hwirq);
		opal_irqs[i] = irq;
	}

	/* Create "opal" kobject under /sys/firmware */
	rc = opal_sysfs_init();
	if (rc == 0) {
		/* Setup error log interface */
		rc = opal_elog_init();
		/* Setup code update interface */
		opal_flash_init();
		/* Setup platform dump extract interface */
		opal_platform_dump_init();
		/* Setup system parameters interface */
		opal_sys_param_init();
		/* Setup message log interface. */
		opal_msglog_init();
	}

	return 0;
}
subsys_initcall(opal_init);

void opal_shutdown(void)
{
	unsigned int i;
	long rc = OPAL_BUSY;

	/* First free interrupts, which will also mask them */
	for (i = 0; i < opal_irq_count; i++) {
		if (opal_irqs[i])
			free_irq(opal_irqs[i], NULL);
		opal_irqs[i] = 0;
	}

	/*
	 * Then sync with OPAL which ensure anything that can
	 * potentially write to our memory has completed such
	 * as an ongoing dump retrieval
	 */
	while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
		rc = opal_sync_host_reboot();
		if (rc == OPAL_BUSY)
			opal_poll_events(NULL);
		else
			mdelay(10);
	}
}

/* Export this so that test modules can use it */
EXPORT_SYMBOL_GPL(opal_invalid_call);

/* Convert a region of vmalloc memory to an opal sg list */
struct opal_sg_list *opal_vmalloc_to_sg_list(void *vmalloc_addr,
					     unsigned long vmalloc_size)
{
	struct opal_sg_list *sg, *first = NULL;
	unsigned long i = 0;

	sg = kzalloc(PAGE_SIZE, GFP_KERNEL);
	if (!sg)
		goto nomem;

	first = sg;

	while (vmalloc_size > 0) {
		uint64_t data = vmalloc_to_pfn(vmalloc_addr) << PAGE_SHIFT;
		uint64_t length = min(vmalloc_size, PAGE_SIZE);

		sg->entry[i].data = cpu_to_be64(data);
		sg->entry[i].length = cpu_to_be64(length);
		i++;

		if (i >= SG_ENTRIES_PER_NODE) {
			struct opal_sg_list *next;

			next = kzalloc(PAGE_SIZE, GFP_KERNEL);
			if (!next)
				goto nomem;

			sg->length = cpu_to_be64(
					i * sizeof(struct opal_sg_entry) + 16);
			i = 0;
			sg->next = cpu_to_be64(__pa(next));
			sg = next;
		}

		vmalloc_addr += length;
		vmalloc_size -= length;
	}

	sg->length = cpu_to_be64(i * sizeof(struct opal_sg_entry) + 16);

	return first;

nomem:
	pr_err("%s : Failed to allocate memory\n", __func__);
	opal_free_sg_list(first);
	return NULL;
}

void opal_free_sg_list(struct opal_sg_list *sg)
{
	while (sg) {
		uint64_t next = be64_to_cpu(sg->next);

		kfree(sg);

		if (next)
			sg = __va(next);
		else
			sg = NULL;
	}
}