summaryrefslogtreecommitdiffstats
path: root/drivers/gpu/drm/xe/xe_gsc_proxy.c
blob: 309ef80e3b95e8febf0f9bc5e6e01ece11c13376 (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
// SPDX-License-Identifier: MIT
/*
 * Copyright © 2023 Intel Corporation
 */

#include "xe_gsc_proxy.h"

#include <linux/component.h>
#include <linux/delay.h>

#include <drm/drm_managed.h>
#include <drm/i915_component.h>
#include <drm/i915_gsc_proxy_mei_interface.h>

#include "abi/gsc_proxy_commands_abi.h"
#include "regs/xe_gsc_regs.h"
#include "xe_bo.h"
#include "xe_gsc.h"
#include "xe_gsc_submit.h"
#include "xe_gt.h"
#include "xe_gt_printk.h"
#include "xe_map.h"
#include "xe_mmio.h"
#include "xe_pm.h"

/*
 * GSC proxy:
 * The GSC uC needs to communicate with the CSME to perform certain operations.
 * Since the GSC can't perform this communication directly on platforms where it
 * is integrated in GT, the graphics driver needs to transfer the messages from
 * GSC to CSME and back. The proxy flow must be manually started after the GSC
 * is loaded to signal to GSC that we're ready to handle its messages and allow
 * it to query its init data from CSME; GSC will then trigger an HECI2 interrupt
 * if it needs to send messages to CSME again.
 * The proxy flow is as follow:
 * 1 - Xe submits a request to GSC asking for the message to CSME
 * 2 - GSC replies with the proxy header + payload for CSME
 * 3 - Xe sends the reply from GSC as-is to CSME via the mei proxy component
 * 4 - CSME replies with the proxy header + payload for GSC
 * 5 - Xe submits a request to GSC with the reply from CSME
 * 6 - GSC replies either with a new header + payload (same as step 2, so we
 *     restart from there) or with an end message.
 */

/*
 * The component should load quite quickly in most cases, but it could take
 * a bit. Using a very big timeout just to cover the worst case scenario
 */
#define GSC_PROXY_INIT_TIMEOUT_MS 20000

/* shorthand define for code compactness */
#define PROXY_HDR_SIZE (sizeof(struct xe_gsc_proxy_header))

/* the protocol supports up to 32K in each direction */
#define GSC_PROXY_BUFFER_SIZE SZ_32K
#define GSC_PROXY_CHANNEL_SIZE (GSC_PROXY_BUFFER_SIZE * 2)

static struct xe_gt *
gsc_to_gt(struct xe_gsc *gsc)
{
	return container_of(gsc, struct xe_gt, uc.gsc);
}

static inline struct xe_device *kdev_to_xe(struct device *kdev)
{
	return dev_get_drvdata(kdev);
}

static bool gsc_proxy_init_done(struct xe_gsc *gsc)
{
	struct xe_gt *gt = gsc_to_gt(gsc);
	u32 fwsts1 = xe_mmio_read32(gt, HECI_FWSTS1(MTL_GSC_HECI1_BASE));

	return REG_FIELD_GET(HECI1_FWSTS1_CURRENT_STATE, fwsts1) ==
	       HECI1_FWSTS1_PROXY_STATE_NORMAL;
}

static void __gsc_proxy_irq_rmw(struct xe_gsc *gsc, u32 clr, u32 set)
{
	struct xe_gt *gt = gsc_to_gt(gsc);

	/* make sure we never accidentally write the RST bit */
	clr |= HECI_H_CSR_RST;

	xe_mmio_rmw32(gt, HECI_H_CSR(MTL_GSC_HECI2_BASE), clr, set);
}

static void gsc_proxy_irq_clear(struct xe_gsc *gsc)
{
	/* The status bit is cleared by writing to it */
	__gsc_proxy_irq_rmw(gsc, 0, HECI_H_CSR_IS);
}

static void gsc_proxy_irq_toggle(struct xe_gsc *gsc, bool enabled)
{
	u32 set = enabled ? HECI_H_CSR_IE : 0;
	u32 clr = enabled ? 0 : HECI_H_CSR_IE;

	__gsc_proxy_irq_rmw(gsc, clr, set);
}

static int proxy_send_to_csme(struct xe_gsc *gsc, u32 size)
{
	struct xe_gt *gt = gsc_to_gt(gsc);
	struct i915_gsc_proxy_component *comp = gsc->proxy.component;
	int ret;

	ret = comp->ops->send(comp->mei_dev, gsc->proxy.to_csme, size);
	if (ret < 0) {
		xe_gt_err(gt, "Failed to send CSME proxy message\n");
		return ret;
	}

	ret = comp->ops->recv(comp->mei_dev, gsc->proxy.from_csme, GSC_PROXY_BUFFER_SIZE);
	if (ret < 0) {
		xe_gt_err(gt, "Failed to receive CSME proxy message\n");
		return ret;
	}

	return ret;
}

static int proxy_send_to_gsc(struct xe_gsc *gsc, u32 size)
{
	struct xe_gt *gt = gsc_to_gt(gsc);
	u64 addr_in = xe_bo_ggtt_addr(gsc->proxy.bo);
	u64 addr_out = addr_in + GSC_PROXY_BUFFER_SIZE;
	int err;

	/* the message must contain at least the gsc and proxy headers */
	if (size > GSC_PROXY_BUFFER_SIZE) {
		xe_gt_err(gt, "Invalid GSC proxy message size: %u\n", size);
		return -EINVAL;
	}

	err = xe_gsc_pkt_submit_kernel(gsc, addr_in, size,
				       addr_out, GSC_PROXY_BUFFER_SIZE);
	if (err) {
		xe_gt_err(gt, "Failed to submit gsc proxy rq (%pe)\n", ERR_PTR(err));
		return err;
	}

	return 0;
}

static int validate_proxy_header(struct xe_gsc_proxy_header *header,
				 u32 source, u32 dest, u32 max_size)
{
	u32 type = FIELD_GET(GSC_PROXY_TYPE, header->hdr);
	u32 length = FIELD_GET(GSC_PROXY_PAYLOAD_LENGTH, header->hdr);

	if (header->destination != dest || header->source != source)
		return -ENOEXEC;

	if (length + PROXY_HDR_SIZE > max_size)
		return -E2BIG;

	switch (type) {
	case GSC_PROXY_MSG_TYPE_PROXY_PAYLOAD:
		if (length > 0)
			break;
		fallthrough;
	case GSC_PROXY_MSG_TYPE_PROXY_INVALID:
		return -EIO;
	default:
		break;
	}

	return 0;
}

#define proxy_header_wr(xe_, map_, offset_, field_, val_) \
	xe_map_wr_field(xe_, map_, offset_, struct xe_gsc_proxy_header, field_, val_)

#define proxy_header_rd(xe_, map_, offset_, field_) \
	xe_map_rd_field(xe_, map_, offset_, struct xe_gsc_proxy_header, field_)

static u32 emit_proxy_header(struct xe_device *xe, struct iosys_map *map, u32 offset)
{
	xe_map_memset(xe, map, offset, 0, PROXY_HDR_SIZE);

	proxy_header_wr(xe, map, offset, hdr,
			FIELD_PREP(GSC_PROXY_TYPE, GSC_PROXY_MSG_TYPE_PROXY_QUERY) |
			FIELD_PREP(GSC_PROXY_PAYLOAD_LENGTH, 0));

	proxy_header_wr(xe, map, offset, source, GSC_PROXY_ADDRESSING_KMD);
	proxy_header_wr(xe, map, offset, destination, GSC_PROXY_ADDRESSING_GSC);
	proxy_header_wr(xe, map, offset, status, 0);

	return offset + PROXY_HDR_SIZE;
}

static int proxy_query(struct xe_gsc *gsc)
{
	struct xe_gt *gt = gsc_to_gt(gsc);
	struct xe_device *xe = gt_to_xe(gt);
	struct xe_gsc_proxy_header *to_csme_hdr = gsc->proxy.to_csme;
	void *to_csme_payload = gsc->proxy.to_csme + PROXY_HDR_SIZE;
	u32 wr_offset;
	u32 reply_offset;
	u32 size;
	int ret;

	wr_offset = xe_gsc_emit_header(xe, &gsc->proxy.to_gsc, 0,
				       HECI_MEADDRESS_PROXY, 0, PROXY_HDR_SIZE);
	wr_offset = emit_proxy_header(xe, &gsc->proxy.to_gsc, wr_offset);

	size = wr_offset;

	while (1) {
		/*
		 * Poison the GSC response header space to make sure we don't
		 * read a stale reply.
		 */
		xe_gsc_poison_header(xe, &gsc->proxy.from_gsc, 0);

		/* send proxy message to GSC */
		ret = proxy_send_to_gsc(gsc, size);
		if (ret)
			goto proxy_error;

		/* check the reply from GSC */
		ret = xe_gsc_read_out_header(xe, &gsc->proxy.from_gsc, 0,
					     PROXY_HDR_SIZE, &reply_offset);
		if (ret) {
			xe_gt_err(gt, "Invalid gsc header in proxy reply (%pe)\n",
				  ERR_PTR(ret));
			goto proxy_error;
		}

		/* copy the proxy header reply from GSC */
		xe_map_memcpy_from(xe, to_csme_hdr, &gsc->proxy.from_gsc,
				   reply_offset, PROXY_HDR_SIZE);

		/* stop if this was the last message */
		if (FIELD_GET(GSC_PROXY_TYPE, to_csme_hdr->hdr) == GSC_PROXY_MSG_TYPE_PROXY_END)
			break;

		/* make sure the GSC-to-CSME proxy header is sane */
		ret = validate_proxy_header(to_csme_hdr,
					    GSC_PROXY_ADDRESSING_GSC,
					    GSC_PROXY_ADDRESSING_CSME,
					    GSC_PROXY_BUFFER_SIZE - reply_offset);
		if (ret) {
			xe_gt_err(gt, "invalid GSC to CSME proxy header! (%pe)\n",
				  ERR_PTR(ret));
			goto proxy_error;
		}

		/* copy the rest of the message */
		size = FIELD_GET(GSC_PROXY_PAYLOAD_LENGTH, to_csme_hdr->hdr);
		xe_map_memcpy_from(xe, to_csme_payload, &gsc->proxy.from_gsc,
				   reply_offset + PROXY_HDR_SIZE, size);

		/* send the GSC message to the CSME */
		ret = proxy_send_to_csme(gsc, size + PROXY_HDR_SIZE);
		if (ret < 0)
			goto proxy_error;

		/* reply size from CSME, including the proxy header */
		size = ret;
		if (size < PROXY_HDR_SIZE) {
			xe_gt_err(gt, "CSME to GSC proxy msg too small: 0x%x\n", size);
			ret = -EPROTO;
			goto proxy_error;
		}

		/* make sure the CSME-to-GSC proxy header is sane */
		ret = validate_proxy_header(gsc->proxy.from_csme,
					    GSC_PROXY_ADDRESSING_CSME,
					    GSC_PROXY_ADDRESSING_GSC,
					    GSC_PROXY_BUFFER_SIZE - reply_offset);
		if (ret) {
			xe_gt_err(gt, "invalid CSME to GSC proxy header! %d\n", ret);
			goto proxy_error;
		}

		/* Emit a new header for sending the reply to the GSC */
		wr_offset = xe_gsc_emit_header(xe, &gsc->proxy.to_gsc, 0,
					       HECI_MEADDRESS_PROXY, 0, size);

		/* copy the CSME reply and update the total msg size to include the GSC header */
		xe_map_memcpy_to(xe, &gsc->proxy.to_gsc, wr_offset, gsc->proxy.from_csme, size);

		size += wr_offset;
	}

proxy_error:
	return ret < 0 ? ret : 0;
}

int xe_gsc_proxy_request_handler(struct xe_gsc *gsc)
{
	struct xe_gt *gt = gsc_to_gt(gsc);
	int slept;
	int err;

	if (!gsc->proxy.component_added)
		return -ENODEV;

	/* when GSC is loaded, we can queue this before the component is bound */
	for (slept = 0; slept < GSC_PROXY_INIT_TIMEOUT_MS; slept += 100) {
		if (gsc->proxy.component)
			break;

		msleep(100);
	}

	mutex_lock(&gsc->proxy.mutex);
	if (!gsc->proxy.component) {
		xe_gt_err(gt, "GSC proxy component not bound!\n");
		err = -EIO;
	} else {
		/*
		 * clear the pending interrupt and allow new proxy requests to
		 * be generated while we handle the current one
		 */
		gsc_proxy_irq_clear(gsc);
		err = proxy_query(gsc);
	}
	mutex_unlock(&gsc->proxy.mutex);
	return err;
}

void xe_gsc_proxy_irq_handler(struct xe_gsc *gsc, u32 iir)
{
	struct xe_gt *gt = gsc_to_gt(gsc);

	if (unlikely(!iir))
		return;

	if (!gsc->proxy.component) {
		xe_gt_err(gt, "GSC proxy irq received without the component being bound!\n");
		return;
	}

	spin_lock(&gsc->lock);
	gsc->work_actions |= GSC_ACTION_SW_PROXY;
	spin_unlock(&gsc->lock);

	queue_work(gsc->wq, &gsc->work);
}

static int xe_gsc_proxy_component_bind(struct device *xe_kdev,
				       struct device *mei_kdev, void *data)
{
	struct xe_device *xe = kdev_to_xe(xe_kdev);
	struct xe_gt *gt = xe->tiles[0].media_gt;
	struct xe_gsc *gsc = &gt->uc.gsc;

	mutex_lock(&gsc->proxy.mutex);
	gsc->proxy.component = data;
	gsc->proxy.component->mei_dev = mei_kdev;
	mutex_unlock(&gsc->proxy.mutex);

	return 0;
}

static void xe_gsc_proxy_component_unbind(struct device *xe_kdev,
					  struct device *mei_kdev, void *data)
{
	struct xe_device *xe = kdev_to_xe(xe_kdev);
	struct xe_gt *gt = xe->tiles[0].media_gt;
	struct xe_gsc *gsc = &gt->uc.gsc;

	xe_gsc_wait_for_worker_completion(gsc);

	mutex_lock(&gsc->proxy.mutex);
	gsc->proxy.component = NULL;
	mutex_unlock(&gsc->proxy.mutex);
}

static const struct component_ops xe_gsc_proxy_component_ops = {
	.bind   = xe_gsc_proxy_component_bind,
	.unbind = xe_gsc_proxy_component_unbind,
};

static void proxy_channel_free(struct drm_device *drm, void *arg)
{
	struct xe_gsc *gsc = arg;

	if (!gsc->proxy.bo)
		return;

	if (gsc->proxy.to_csme) {
		kfree(gsc->proxy.to_csme);
		gsc->proxy.to_csme = NULL;
		gsc->proxy.from_csme = NULL;
	}

	if (gsc->proxy.bo) {
		iosys_map_clear(&gsc->proxy.to_gsc);
		iosys_map_clear(&gsc->proxy.from_gsc);
		xe_bo_unpin_map_no_vm(gsc->proxy.bo);
		gsc->proxy.bo = NULL;
	}
}

static int proxy_channel_alloc(struct xe_gsc *gsc)
{
	struct xe_gt *gt = gsc_to_gt(gsc);
	struct xe_tile *tile = gt_to_tile(gt);
	struct xe_device *xe = gt_to_xe(gt);
	struct xe_bo *bo;
	void *csme;
	int err;

	csme = kzalloc(GSC_PROXY_CHANNEL_SIZE, GFP_KERNEL);
	if (!csme)
		return -ENOMEM;

	bo = xe_bo_create_pin_map(xe, tile, NULL, GSC_PROXY_CHANNEL_SIZE,
				  ttm_bo_type_kernel,
				  XE_BO_CREATE_SYSTEM_BIT |
				  XE_BO_CREATE_GGTT_BIT);
	if (IS_ERR(bo)) {
		kfree(csme);
		return PTR_ERR(bo);
	}

	gsc->proxy.bo = bo;
	gsc->proxy.to_gsc = IOSYS_MAP_INIT_OFFSET(&bo->vmap, 0);
	gsc->proxy.from_gsc = IOSYS_MAP_INIT_OFFSET(&bo->vmap, GSC_PROXY_BUFFER_SIZE);
	gsc->proxy.to_csme = csme;
	gsc->proxy.from_csme = csme + GSC_PROXY_BUFFER_SIZE;

	err = drmm_add_action_or_reset(&xe->drm, proxy_channel_free, gsc);
	if (err)
		return err;

	return 0;
}

/**
 * xe_gsc_proxy_init() - init objects and MEI component required by GSC proxy
 * @gsc: the GSC uC
 *
 * Return: 0 if the initialization was successful, a negative errno otherwise.
 */
int xe_gsc_proxy_init(struct xe_gsc *gsc)
{
	int err;
	struct xe_gt *gt = gsc_to_gt(gsc);
	struct xe_tile *tile = gt_to_tile(gt);
	struct xe_device *xe = tile_to_xe(tile);

	mutex_init(&gsc->proxy.mutex);

	if (!IS_ENABLED(CONFIG_INTEL_MEI_GSC_PROXY)) {
		xe_gt_info(gt, "can't init GSC proxy due to missing mei component\n");
		return -ENODEV;
	}

	/* no multi-tile devices with this feature yet */
	if (tile->id > 0) {
		xe_gt_err(gt, "unexpected GSC proxy init on tile %u\n", tile->id);
		return -EINVAL;
	}

	err = proxy_channel_alloc(gsc);
	if (err)
		return err;

	err = component_add_typed(xe->drm.dev, &xe_gsc_proxy_component_ops,
				  I915_COMPONENT_GSC_PROXY);
	if (err < 0) {
		xe_gt_err(gt, "Failed to add GSC_PROXY component (%pe)\n", ERR_PTR(err));
		return err;
	}

	gsc->proxy.component_added = true;

	/* the component must be removed before unload, so can't use drmm for cleanup */

	return 0;
}

/**
 * xe_gsc_proxy_remove() - remove the GSC proxy MEI component
 * @gsc: the GSC uC
 */
void xe_gsc_proxy_remove(struct xe_gsc *gsc)
{
	struct xe_gt *gt = gsc_to_gt(gsc);
	struct xe_device *xe = gt_to_xe(gt);
	int err = 0;

	if (!gsc->proxy.component_added)
		return;

	/* disable HECI2 IRQs */
	xe_pm_runtime_get(xe);
	err = xe_force_wake_get(gt_to_fw(gt), XE_FW_GSC);
	if (err)
		xe_gt_err(gt, "failed to get forcewake to disable GSC interrupts\n");

	/* try do disable irq even if forcewake failed */
	gsc_proxy_irq_toggle(gsc, false);

	if (!err)
		xe_force_wake_put(gt_to_fw(gt), XE_FW_GSC);
	xe_pm_runtime_put(xe);

	xe_gsc_wait_for_worker_completion(gsc);

	component_del(xe->drm.dev, &xe_gsc_proxy_component_ops);
	gsc->proxy.component_added = false;
}

/**
 * xe_gsc_proxy_start() - start the proxy by submitting the first request
 * @gsc: the GSC uC
 *
 * Return: 0 if the proxy are now enabled, a negative errno otherwise.
 */
int xe_gsc_proxy_start(struct xe_gsc *gsc)
{
	int err;

	/* enable the proxy interrupt in the GSC shim layer */
	gsc_proxy_irq_toggle(gsc, true);

	/*
	 * The handling of the first proxy request must be manually triggered to
	 * notify the GSC that we're ready to support the proxy flow.
	 */
	err = xe_gsc_proxy_request_handler(gsc);
	if (err)
		return err;

	if (!gsc_proxy_init_done(gsc)) {
		xe_gt_err(gsc_to_gt(gsc), "GSC FW reports proxy init not completed\n");
		return -EIO;
	}

	return 0;
}