summaryrefslogtreecommitdiffstats
path: root/drivers/pci/hotplug/acpi_pcihp.c
blob: 095f29e13734ad8e830e2614a42b7dc6c5d4a2b8 (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
/*
 * Common ACPI functions for hot plug platforms
 *
 * Copyright (C) 2006 Intel Corporation
 *
 * All rights reserved.
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
 * NON INFRINGEMENT.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * Send feedback to <kristen.c.accardi@intel.com>
 *
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/pci.h>
#include <linux/pci_hotplug.h>
#include <linux/acpi.h>
#include <linux/pci-acpi.h>
#include <linux/slab.h>

#define MY_NAME	"acpi_pcihp"

#define dbg(fmt, arg...) do { if (debug_acpi) printk(KERN_DEBUG "%s: %s: " fmt , MY_NAME , __func__ , ## arg); } while (0)
#define err(format, arg...) printk(KERN_ERR "%s: " format , MY_NAME , ## arg)
#define info(format, arg...) printk(KERN_INFO "%s: " format , MY_NAME , ## arg)
#define warn(format, arg...) printk(KERN_WARNING "%s: " format , MY_NAME , ## arg)

#define	METHOD_NAME__SUN	"_SUN"
#define	METHOD_NAME_OSHP	"OSHP"

static int debug_acpi;

static acpi_status
decode_type0_hpx_record(union acpi_object *record, struct hotplug_params *hpx)
{
	int i;
	union acpi_object *fields = record->package.elements;
	u32 revision = fields[1].integer.value;

	switch (revision) {
	case 1:
		if (record->package.count != 6)
			return AE_ERROR;
		for (i = 2; i < 6; i++)
			if (fields[i].type != ACPI_TYPE_INTEGER)
				return AE_ERROR;
		hpx->t0 = &hpx->type0_data;
		hpx->t0->revision        = revision;
		hpx->t0->cache_line_size = fields[2].integer.value;
		hpx->t0->latency_timer   = fields[3].integer.value;
		hpx->t0->enable_serr     = fields[4].integer.value;
		hpx->t0->enable_perr     = fields[5].integer.value;
		break;
	default:
		printk(KERN_WARNING
		       "%s: Type 0 Revision %d record not supported\n",
		       __func__, revision);
		return AE_ERROR;
	}
	return AE_OK;
}

static acpi_status
decode_type1_hpx_record(union acpi_object *record, struct hotplug_params *hpx)
{
	int i;
	union acpi_object *fields = record->package.elements;
	u32 revision = fields[1].integer.value;

	switch (revision) {
	case 1:
		if (record->package.count != 5)
			return AE_ERROR;
		for (i = 2; i < 5; i++)
			if (fields[i].type != ACPI_TYPE_INTEGER)
				return AE_ERROR;
		hpx->t1 = &hpx->type1_data;
		hpx->t1->revision      = revision;
		hpx->t1->max_mem_read  = fields[2].integer.value;
		hpx->t1->avg_max_split = fields[3].integer.value;
		hpx->t1->tot_max_split = fields[4].integer.value;
		break;
	default:
		printk(KERN_WARNING
		       "%s: Type 1 Revision %d record not supported\n",
		       __func__, revision);
		return AE_ERROR;
	}
	return AE_OK;
}

static acpi_status
decode_type2_hpx_record(union acpi_object *record, struct hotplug_params *hpx)
{
	int i;
	union acpi_object *fields = record->package.elements;
	u32 revision = fields[1].integer.value;

	switch (revision) {
	case 1:
		if (record->package.count != 18)
			return AE_ERROR;
		for (i = 2; i < 18; i++)
			if (fields[i].type != ACPI_TYPE_INTEGER)
				return AE_ERROR;
		hpx->t2 = &hpx->type2_data;
		hpx->t2->revision      = revision;
		hpx->t2->unc_err_mask_and      = fields[2].integer.value;
		hpx->t2->unc_err_mask_or       = fields[3].integer.value;
		hpx->t2->unc_err_sever_and     = fields[4].integer.value;
		hpx->t2->unc_err_sever_or      = fields[5].integer.value;
		hpx->t2->cor_err_mask_and      = fields[6].integer.value;
		hpx->t2->cor_err_mask_or       = fields[7].integer.value;
		hpx->t2->adv_err_cap_and       = fields[8].integer.value;
		hpx->t2->adv_err_cap_or        = fields[9].integer.value;
		hpx->t2->pci_exp_devctl_and    = fields[10].integer.value;
		hpx->t2->pci_exp_devctl_or     = fields[11].integer.value;
		hpx->t2->pci_exp_lnkctl_and    = fields[12].integer.value;
		hpx->t2->pci_exp_lnkctl_or     = fields[13].integer.value;
		hpx->t2->sec_unc_err_sever_and = fields[14].integer.value;
		hpx->t2->sec_unc_err_sever_or  = fields[15].integer.value;
		hpx->t2->sec_unc_err_mask_and  = fields[16].integer.value;
		hpx->t2->sec_unc_err_mask_or   = fields[17].integer.value;
		break;
	default:
		printk(KERN_WARNING
		       "%s: Type 2 Revision %d record not supported\n",
		       __func__, revision);
		return AE_ERROR;
	}
	return AE_OK;
}

static acpi_status
acpi_run_hpx(acpi_handle handle, struct hotplug_params *hpx)
{
	acpi_status status;
	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
	union acpi_object *package, *record, *fields;
	u32 type;
	int i;

	/* Clear the return buffer with zeros */
	memset(hpx, 0, sizeof(struct hotplug_params));

	status = acpi_evaluate_object(handle, "_HPX", NULL, &buffer);
	if (ACPI_FAILURE(status))
		return status;

	package = (union acpi_object *)buffer.pointer;
	if (package->type != ACPI_TYPE_PACKAGE) {
		status = AE_ERROR;
		goto exit;
	}

	for (i = 0; i < package->package.count; i++) {
		record = &package->package.elements[i];
		if (record->type != ACPI_TYPE_PACKAGE) {
			status = AE_ERROR;
			goto exit;
		}

		fields = record->package.elements;
		if (fields[0].type != ACPI_TYPE_INTEGER ||
		    fields[1].type != ACPI_TYPE_INTEGER) {
			status = AE_ERROR;
			goto exit;
		}

		type = fields[0].integer.value;
		switch (type) {
		case 0:
			status = decode_type0_hpx_record(record, hpx);
			if (ACPI_FAILURE(status))
				goto exit;
			break;
		case 1:
			status = decode_type1_hpx_record(record, hpx);
			if (ACPI_FAILURE(status))
				goto exit;
			break;
		case 2:
			status = decode_type2_hpx_record(record, hpx);
			if (ACPI_FAILURE(status))
				goto exit;
			break;
		default:
			printk(KERN_ERR "%s: Type %d record not supported\n",
			       __func__, type);
			status = AE_ERROR;
			goto exit;
		}
	}
 exit:
	kfree(buffer.pointer);
	return status;
}

static acpi_status
acpi_run_hpp(acpi_handle handle, struct hotplug_params *hpp)
{
	acpi_status status;
	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
	union acpi_object *package, *fields;
	int i;

	memset(hpp, 0, sizeof(struct hotplug_params));

	status = acpi_evaluate_object(handle, "_HPP", NULL, &buffer);
	if (ACPI_FAILURE(status))
		return status;

	package = (union acpi_object *) buffer.pointer;
	if (package->type != ACPI_TYPE_PACKAGE ||
	    package->package.count != 4) {
		status = AE_ERROR;
		goto exit;
	}

	fields = package->package.elements;
	for (i = 0; i < 4; i++) {
		if (fields[i].type != ACPI_TYPE_INTEGER) {
			status = AE_ERROR;
			goto exit;
		}
	}

	hpp->t0 = &hpp->type0_data;
	hpp->t0->revision        = 1;
	hpp->t0->cache_line_size = fields[0].integer.value;
	hpp->t0->latency_timer   = fields[1].integer.value;
	hpp->t0->enable_serr     = fields[2].integer.value;
	hpp->t0->enable_perr     = fields[3].integer.value;

exit:
	kfree(buffer.pointer);
	return status;
}



/* acpi_run_oshp - get control of hotplug from the firmware
 *
 * @handle - the handle of the hotplug controller.
 */
static acpi_status acpi_run_oshp(acpi_handle handle)
{
	acpi_status		status;
	struct acpi_buffer	string = { ACPI_ALLOCATE_BUFFER, NULL };

	acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);

	/* run OSHP */
	status = acpi_evaluate_object(handle, METHOD_NAME_OSHP, NULL, NULL);
	if (ACPI_FAILURE(status))
		if (status != AE_NOT_FOUND)
			printk(KERN_ERR "%s:%s OSHP fails=0x%x\n",
			       __func__, (char *)string.pointer, status);
		else
			dbg("%s:%s OSHP not found\n",
			    __func__, (char *)string.pointer);
	else
		pr_debug("%s:%s OSHP passes\n", __func__,
			(char *)string.pointer);

	kfree(string.pointer);
	return status;
}

/* pci_get_hp_params
 *
 * @dev - the pci_dev for which we want parameters
 * @hpp - allocated by the caller
 */
int pci_get_hp_params(struct pci_dev *dev, struct hotplug_params *hpp)
{
	acpi_status status;
	acpi_handle handle, phandle;
	struct pci_bus *pbus;

	handle = NULL;
	for (pbus = dev->bus; pbus; pbus = pbus->parent) {
		handle = acpi_pci_get_bridge_handle(pbus);
		if (handle)
			break;
	}

	/*
	 * _HPP settings apply to all child buses, until another _HPP is
	 * encountered. If we don't find an _HPP for the input pci dev,
	 * look for it in the parent device scope since that would apply to
	 * this pci dev.
	 */
	while (handle) {
		status = acpi_run_hpx(handle, hpp);
		if (ACPI_SUCCESS(status))
			return 0;
		status = acpi_run_hpp(handle, hpp);
		if (ACPI_SUCCESS(status))
			return 0;
		if (acpi_is_root_bridge(handle))
			break;
		status = acpi_get_parent(handle, &phandle);
		if (ACPI_FAILURE(status))
			break;
		handle = phandle;
	}
	return -ENODEV;
}
EXPORT_SYMBOL_GPL(pci_get_hp_params);

/**
 * acpi_get_hp_hw_control_from_firmware
 * @dev: the pci_dev of the bridge that has a hotplug controller
 * @flags: requested control bits for _OSC
 *
 * Attempt to take hotplug control from firmware.
 */
int acpi_get_hp_hw_control_from_firmware(struct pci_dev *pdev, u32 flags)
{
	acpi_status status;
	acpi_handle chandle, handle;
	struct acpi_buffer string = { ACPI_ALLOCATE_BUFFER, NULL };

	flags &= OSC_SHPC_NATIVE_HP_CONTROL;
	if (!flags) {
		err("Invalid flags %u specified!\n", flags);
		return -EINVAL;
	}

	/*
	 * Per PCI firmware specification, we should run the ACPI _OSC
	 * method to get control of hotplug hardware before using it. If
	 * an _OSC is missing, we look for an OSHP to do the same thing.
	 * To handle different BIOS behavior, we look for _OSC on a root
	 * bridge preferentially (according to PCI fw spec). Later for
	 * OSHP within the scope of the hotplug controller and its parents,
	 * up to the host bridge under which this controller exists.
	 */
	handle = acpi_find_root_bridge_handle(pdev);
	if (handle) {
		acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);
		dbg("Trying to get hotplug control for %s\n",
				(char *)string.pointer);
		status = acpi_pci_osc_control_set(handle, &flags, flags);
		if (ACPI_SUCCESS(status))
			goto got_one;
		if (status == AE_SUPPORT)
			goto no_control;
		kfree(string.pointer);
		string = (struct acpi_buffer){ ACPI_ALLOCATE_BUFFER, NULL };
	}

	handle = DEVICE_ACPI_HANDLE(&pdev->dev);
	if (!handle) {
		/*
		 * This hotplug controller was not listed in the ACPI name
		 * space at all. Try to get acpi handle of parent pci bus.
		 */
		struct pci_bus *pbus;
		for (pbus = pdev->bus; pbus; pbus = pbus->parent) {
			handle = acpi_pci_get_bridge_handle(pbus);
			if (handle)
				break;
		}
	}

	while (handle) {
		acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);
		dbg("Trying to get hotplug control for %s \n",
		    (char *)string.pointer);
		status = acpi_run_oshp(handle);
		if (ACPI_SUCCESS(status))
			goto got_one;
		if (acpi_is_root_bridge(handle))
			break;
		chandle = handle;
		status = acpi_get_parent(chandle, &handle);
		if (ACPI_FAILURE(status))
			break;
	}
no_control:
	dbg("Cannot get control of hotplug hardware for pci %s\n",
	    pci_name(pdev));
	kfree(string.pointer);
	return -ENODEV;
got_one:
	dbg("Gained control for hotplug HW for pci %s (%s)\n",
	    pci_name(pdev), (char *)string.pointer);
	kfree(string.pointer);
	return 0;
}
EXPORT_SYMBOL(acpi_get_hp_hw_control_from_firmware);

static int pcihp_is_ejectable(acpi_handle handle)
{
	acpi_status status;
	acpi_handle tmp;
	unsigned long long removable;
	status = acpi_get_handle(handle, "_ADR", &tmp);
	if (ACPI_FAILURE(status))
		return 0;
	status = acpi_get_handle(handle, "_EJ0", &tmp);
	if (ACPI_SUCCESS(status))
		return 1;
	status = acpi_evaluate_integer(handle, "_RMV", NULL, &removable);
	if (ACPI_SUCCESS(status) && removable)
		return 1;
	return 0;
}

/**
 * acpi_pcihp_check_ejectable - check if handle is ejectable ACPI PCI slot
 * @pbus: the PCI bus of the PCI slot corresponding to 'handle'
 * @handle: ACPI handle to check
 *
 * Return 1 if handle is ejectable PCI slot, 0 otherwise.
 */
int acpi_pci_check_ejectable(struct pci_bus *pbus, acpi_handle handle)
{
	acpi_handle bridge_handle, parent_handle;

	if (!(bridge_handle = acpi_pci_get_bridge_handle(pbus)))
		return 0;
	if ((ACPI_FAILURE(acpi_get_parent(handle, &parent_handle))))
		return 0;
	if (bridge_handle != parent_handle)
		return 0;
	return pcihp_is_ejectable(handle);
}
EXPORT_SYMBOL_GPL(acpi_pci_check_ejectable);

static acpi_status
check_hotplug(acpi_handle handle, u32 lvl, void *context, void **rv)
{
	int *found = (int *)context;
	if (pcihp_is_ejectable(handle)) {
		*found = 1;
		return AE_CTRL_TERMINATE;
	}
	return AE_OK;
}

/**
 * acpi_pci_detect_ejectable - check if the PCI bus has ejectable slots
 * @handle - handle of the PCI bus to scan
 *
 * Returns 1 if the PCI bus has ACPI based ejectable slots, 0 otherwise.
 */
int acpi_pci_detect_ejectable(acpi_handle handle)
{
	int found = 0;

	if (!handle)
		return found;

	acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
			    check_hotplug, NULL, (void *)&found, NULL);
	return found;
}
EXPORT_SYMBOL_GPL(acpi_pci_detect_ejectable);

module_param(debug_acpi, bool, 0644);
MODULE_PARM_DESC(debug_acpi, "Debugging mode for ACPI enabled or not");
OpenPOWER on IntegriCloud