xref: /linux/drivers/gpu/drm/panthor/panthor_device.c (revision 6e7fd890f1d6ac83805409e9c346240de2705584)
1 // SPDX-License-Identifier: GPL-2.0 or MIT
2 /* Copyright 2018 Marty E. Plummer <hanetzer@startmail.com> */
3 /* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
4 /* Copyright 2023 Collabora ltd. */
5 
6 #include <linux/clk.h>
7 #include <linux/mm.h>
8 #include <linux/platform_device.h>
9 #include <linux/pm_domain.h>
10 #include <linux/pm_runtime.h>
11 #include <linux/regulator/consumer.h>
12 #include <linux/reset.h>
13 
14 #include <drm/drm_drv.h>
15 #include <drm/drm_managed.h>
16 
17 #include "panthor_devfreq.h"
18 #include "panthor_device.h"
19 #include "panthor_fw.h"
20 #include "panthor_gpu.h"
21 #include "panthor_mmu.h"
22 #include "panthor_regs.h"
23 #include "panthor_sched.h"
24 
25 static int panthor_clk_init(struct panthor_device *ptdev)
26 {
27 	ptdev->clks.core = devm_clk_get(ptdev->base.dev, NULL);
28 	if (IS_ERR(ptdev->clks.core))
29 		return dev_err_probe(ptdev->base.dev,
30 				     PTR_ERR(ptdev->clks.core),
31 				     "get 'core' clock failed");
32 
33 	ptdev->clks.stacks = devm_clk_get_optional(ptdev->base.dev, "stacks");
34 	if (IS_ERR(ptdev->clks.stacks))
35 		return dev_err_probe(ptdev->base.dev,
36 				     PTR_ERR(ptdev->clks.stacks),
37 				     "get 'stacks' clock failed");
38 
39 	ptdev->clks.coregroup = devm_clk_get_optional(ptdev->base.dev, "coregroup");
40 	if (IS_ERR(ptdev->clks.coregroup))
41 		return dev_err_probe(ptdev->base.dev,
42 				     PTR_ERR(ptdev->clks.coregroup),
43 				     "get 'coregroup' clock failed");
44 
45 	drm_info(&ptdev->base, "clock rate = %lu\n", clk_get_rate(ptdev->clks.core));
46 	return 0;
47 }
48 
49 void panthor_device_unplug(struct panthor_device *ptdev)
50 {
51 	/* This function can be called from two different path: the reset work
52 	 * and the platform device remove callback. drm_dev_unplug() doesn't
53 	 * deal with concurrent callers, so we have to protect drm_dev_unplug()
54 	 * calls with our own lock, and bail out if the device is already
55 	 * unplugged.
56 	 */
57 	mutex_lock(&ptdev->unplug.lock);
58 	if (drm_dev_is_unplugged(&ptdev->base)) {
59 		/* Someone beat us, release the lock and wait for the unplug
60 		 * operation to be reported as done.
61 		 **/
62 		mutex_unlock(&ptdev->unplug.lock);
63 		wait_for_completion(&ptdev->unplug.done);
64 		return;
65 	}
66 
67 	/* Call drm_dev_unplug() so any access to HW blocks happening after
68 	 * that point get rejected.
69 	 */
70 	drm_dev_unplug(&ptdev->base);
71 
72 	/* We do the rest of the unplug with the unplug lock released,
73 	 * future callers will wait on ptdev->unplug.done anyway.
74 	 */
75 	mutex_unlock(&ptdev->unplug.lock);
76 
77 	drm_WARN_ON(&ptdev->base, pm_runtime_get_sync(ptdev->base.dev) < 0);
78 
79 	/* Now, try to cleanly shutdown the GPU before the device resources
80 	 * get reclaimed.
81 	 */
82 	panthor_sched_unplug(ptdev);
83 	panthor_fw_unplug(ptdev);
84 	panthor_mmu_unplug(ptdev);
85 	panthor_gpu_unplug(ptdev);
86 
87 	pm_runtime_dont_use_autosuspend(ptdev->base.dev);
88 	pm_runtime_put_sync_suspend(ptdev->base.dev);
89 
90 	/* If PM is disabled, we need to call the suspend handler manually. */
91 	if (!IS_ENABLED(CONFIG_PM))
92 		panthor_device_suspend(ptdev->base.dev);
93 
94 	/* Report the unplug operation as done to unblock concurrent
95 	 * panthor_device_unplug() callers.
96 	 */
97 	complete_all(&ptdev->unplug.done);
98 }
99 
100 static void panthor_device_reset_cleanup(struct drm_device *ddev, void *data)
101 {
102 	struct panthor_device *ptdev = container_of(ddev, struct panthor_device, base);
103 
104 	cancel_work_sync(&ptdev->reset.work);
105 	destroy_workqueue(ptdev->reset.wq);
106 }
107 
108 static void panthor_device_reset_work(struct work_struct *work)
109 {
110 	struct panthor_device *ptdev = container_of(work, struct panthor_device, reset.work);
111 	int ret = 0, cookie;
112 
113 	if (atomic_read(&ptdev->pm.state) != PANTHOR_DEVICE_PM_STATE_ACTIVE) {
114 		/*
115 		 * No need for a reset as the device has been (or will be)
116 		 * powered down
117 		 */
118 		atomic_set(&ptdev->reset.pending, 0);
119 		return;
120 	}
121 
122 	if (!drm_dev_enter(&ptdev->base, &cookie))
123 		return;
124 
125 	panthor_sched_pre_reset(ptdev);
126 	panthor_fw_pre_reset(ptdev, true);
127 	panthor_mmu_pre_reset(ptdev);
128 	panthor_gpu_soft_reset(ptdev);
129 	panthor_gpu_l2_power_on(ptdev);
130 	panthor_mmu_post_reset(ptdev);
131 	ret = panthor_fw_post_reset(ptdev);
132 	atomic_set(&ptdev->reset.pending, 0);
133 	panthor_sched_post_reset(ptdev, ret != 0);
134 	drm_dev_exit(cookie);
135 
136 	if (ret) {
137 		panthor_device_unplug(ptdev);
138 		drm_err(&ptdev->base, "Failed to boot MCU after reset, making device unusable.");
139 	}
140 }
141 
142 static bool panthor_device_is_initialized(struct panthor_device *ptdev)
143 {
144 	return !!ptdev->scheduler;
145 }
146 
147 static void panthor_device_free_page(struct drm_device *ddev, void *data)
148 {
149 	__free_page(data);
150 }
151 
152 int panthor_device_init(struct panthor_device *ptdev)
153 {
154 	u32 *dummy_page_virt;
155 	struct resource *res;
156 	struct page *p;
157 	int ret;
158 
159 	ptdev->coherent = device_get_dma_attr(ptdev->base.dev) == DEV_DMA_COHERENT;
160 
161 	init_completion(&ptdev->unplug.done);
162 	ret = drmm_mutex_init(&ptdev->base, &ptdev->unplug.lock);
163 	if (ret)
164 		return ret;
165 
166 	ret = drmm_mutex_init(&ptdev->base, &ptdev->pm.mmio_lock);
167 	if (ret)
168 		return ret;
169 
170 	atomic_set(&ptdev->pm.state, PANTHOR_DEVICE_PM_STATE_SUSPENDED);
171 	p = alloc_page(GFP_KERNEL | __GFP_ZERO);
172 	if (!p)
173 		return -ENOMEM;
174 
175 	ptdev->pm.dummy_latest_flush = p;
176 	dummy_page_virt = page_address(p);
177 	ret = drmm_add_action_or_reset(&ptdev->base, panthor_device_free_page,
178 				       ptdev->pm.dummy_latest_flush);
179 	if (ret)
180 		return ret;
181 
182 	/*
183 	 * Set the dummy page holding the latest flush to 1. This will cause the
184 	 * flush to avoided as we know it isn't necessary if the submission
185 	 * happens while the dummy page is mapped. Zero cannot be used because
186 	 * that means 'always flush'.
187 	 */
188 	*dummy_page_virt = 1;
189 
190 	INIT_WORK(&ptdev->reset.work, panthor_device_reset_work);
191 	ptdev->reset.wq = alloc_ordered_workqueue("panthor-reset-wq", 0);
192 	if (!ptdev->reset.wq)
193 		return -ENOMEM;
194 
195 	ret = drmm_add_action_or_reset(&ptdev->base, panthor_device_reset_cleanup, NULL);
196 	if (ret)
197 		return ret;
198 
199 	ret = panthor_clk_init(ptdev);
200 	if (ret)
201 		return ret;
202 
203 	ret = panthor_devfreq_init(ptdev);
204 	if (ret)
205 		return ret;
206 
207 	ptdev->iomem = devm_platform_get_and_ioremap_resource(to_platform_device(ptdev->base.dev),
208 							      0, &res);
209 	if (IS_ERR(ptdev->iomem))
210 		return PTR_ERR(ptdev->iomem);
211 
212 	ptdev->phys_addr = res->start;
213 
214 	ret = devm_pm_runtime_enable(ptdev->base.dev);
215 	if (ret)
216 		return ret;
217 
218 	ret = pm_runtime_resume_and_get(ptdev->base.dev);
219 	if (ret)
220 		return ret;
221 
222 	/* If PM is disabled, we need to call panthor_device_resume() manually. */
223 	if (!IS_ENABLED(CONFIG_PM)) {
224 		ret = panthor_device_resume(ptdev->base.dev);
225 		if (ret)
226 			return ret;
227 	}
228 
229 	ret = panthor_gpu_init(ptdev);
230 	if (ret)
231 		goto err_rpm_put;
232 
233 	ret = panthor_mmu_init(ptdev);
234 	if (ret)
235 		goto err_unplug_gpu;
236 
237 	ret = panthor_fw_init(ptdev);
238 	if (ret)
239 		goto err_unplug_mmu;
240 
241 	ret = panthor_sched_init(ptdev);
242 	if (ret)
243 		goto err_unplug_fw;
244 
245 	/* ~3 frames */
246 	pm_runtime_set_autosuspend_delay(ptdev->base.dev, 50);
247 	pm_runtime_use_autosuspend(ptdev->base.dev);
248 
249 	ret = drm_dev_register(&ptdev->base, 0);
250 	if (ret)
251 		goto err_disable_autosuspend;
252 
253 	pm_runtime_put_autosuspend(ptdev->base.dev);
254 	return 0;
255 
256 err_disable_autosuspend:
257 	pm_runtime_dont_use_autosuspend(ptdev->base.dev);
258 	panthor_sched_unplug(ptdev);
259 
260 err_unplug_fw:
261 	panthor_fw_unplug(ptdev);
262 
263 err_unplug_mmu:
264 	panthor_mmu_unplug(ptdev);
265 
266 err_unplug_gpu:
267 	panthor_gpu_unplug(ptdev);
268 
269 err_rpm_put:
270 	pm_runtime_put_sync_suspend(ptdev->base.dev);
271 	return ret;
272 }
273 
274 #define PANTHOR_EXCEPTION(id) \
275 	[DRM_PANTHOR_EXCEPTION_ ## id] = { \
276 		.name = #id, \
277 	}
278 
279 struct panthor_exception_info {
280 	const char *name;
281 };
282 
283 static const struct panthor_exception_info panthor_exception_infos[] = {
284 	PANTHOR_EXCEPTION(OK),
285 	PANTHOR_EXCEPTION(TERMINATED),
286 	PANTHOR_EXCEPTION(KABOOM),
287 	PANTHOR_EXCEPTION(EUREKA),
288 	PANTHOR_EXCEPTION(ACTIVE),
289 	PANTHOR_EXCEPTION(CS_RES_TERM),
290 	PANTHOR_EXCEPTION(CS_CONFIG_FAULT),
291 	PANTHOR_EXCEPTION(CS_UNRECOVERABLE),
292 	PANTHOR_EXCEPTION(CS_ENDPOINT_FAULT),
293 	PANTHOR_EXCEPTION(CS_BUS_FAULT),
294 	PANTHOR_EXCEPTION(CS_INSTR_INVALID),
295 	PANTHOR_EXCEPTION(CS_CALL_STACK_OVERFLOW),
296 	PANTHOR_EXCEPTION(CS_INHERIT_FAULT),
297 	PANTHOR_EXCEPTION(INSTR_INVALID_PC),
298 	PANTHOR_EXCEPTION(INSTR_INVALID_ENC),
299 	PANTHOR_EXCEPTION(INSTR_BARRIER_FAULT),
300 	PANTHOR_EXCEPTION(DATA_INVALID_FAULT),
301 	PANTHOR_EXCEPTION(TILE_RANGE_FAULT),
302 	PANTHOR_EXCEPTION(ADDR_RANGE_FAULT),
303 	PANTHOR_EXCEPTION(IMPRECISE_FAULT),
304 	PANTHOR_EXCEPTION(OOM),
305 	PANTHOR_EXCEPTION(CSF_FW_INTERNAL_ERROR),
306 	PANTHOR_EXCEPTION(CSF_RES_EVICTION_TIMEOUT),
307 	PANTHOR_EXCEPTION(GPU_BUS_FAULT),
308 	PANTHOR_EXCEPTION(GPU_SHAREABILITY_FAULT),
309 	PANTHOR_EXCEPTION(SYS_SHAREABILITY_FAULT),
310 	PANTHOR_EXCEPTION(GPU_CACHEABILITY_FAULT),
311 	PANTHOR_EXCEPTION(TRANSLATION_FAULT_0),
312 	PANTHOR_EXCEPTION(TRANSLATION_FAULT_1),
313 	PANTHOR_EXCEPTION(TRANSLATION_FAULT_2),
314 	PANTHOR_EXCEPTION(TRANSLATION_FAULT_3),
315 	PANTHOR_EXCEPTION(TRANSLATION_FAULT_4),
316 	PANTHOR_EXCEPTION(PERM_FAULT_0),
317 	PANTHOR_EXCEPTION(PERM_FAULT_1),
318 	PANTHOR_EXCEPTION(PERM_FAULT_2),
319 	PANTHOR_EXCEPTION(PERM_FAULT_3),
320 	PANTHOR_EXCEPTION(ACCESS_FLAG_1),
321 	PANTHOR_EXCEPTION(ACCESS_FLAG_2),
322 	PANTHOR_EXCEPTION(ACCESS_FLAG_3),
323 	PANTHOR_EXCEPTION(ADDR_SIZE_FAULT_IN),
324 	PANTHOR_EXCEPTION(ADDR_SIZE_FAULT_OUT0),
325 	PANTHOR_EXCEPTION(ADDR_SIZE_FAULT_OUT1),
326 	PANTHOR_EXCEPTION(ADDR_SIZE_FAULT_OUT2),
327 	PANTHOR_EXCEPTION(ADDR_SIZE_FAULT_OUT3),
328 	PANTHOR_EXCEPTION(MEM_ATTR_FAULT_0),
329 	PANTHOR_EXCEPTION(MEM_ATTR_FAULT_1),
330 	PANTHOR_EXCEPTION(MEM_ATTR_FAULT_2),
331 	PANTHOR_EXCEPTION(MEM_ATTR_FAULT_3),
332 };
333 
334 const char *panthor_exception_name(struct panthor_device *ptdev, u32 exception_code)
335 {
336 	if (exception_code >= ARRAY_SIZE(panthor_exception_infos) ||
337 	    !panthor_exception_infos[exception_code].name)
338 		return "Unknown exception type";
339 
340 	return panthor_exception_infos[exception_code].name;
341 }
342 
343 static vm_fault_t panthor_mmio_vm_fault(struct vm_fault *vmf)
344 {
345 	struct vm_area_struct *vma = vmf->vma;
346 	struct panthor_device *ptdev = vma->vm_private_data;
347 	u64 offset = (u64)vma->vm_pgoff << PAGE_SHIFT;
348 	unsigned long pfn;
349 	pgprot_t pgprot;
350 	vm_fault_t ret;
351 	bool active;
352 	int cookie;
353 
354 	if (!drm_dev_enter(&ptdev->base, &cookie))
355 		return VM_FAULT_SIGBUS;
356 
357 	mutex_lock(&ptdev->pm.mmio_lock);
358 	active = atomic_read(&ptdev->pm.state) == PANTHOR_DEVICE_PM_STATE_ACTIVE;
359 
360 	switch (offset) {
361 	case DRM_PANTHOR_USER_FLUSH_ID_MMIO_OFFSET:
362 		if (active)
363 			pfn = __phys_to_pfn(ptdev->phys_addr + CSF_GPU_LATEST_FLUSH_ID);
364 		else
365 			pfn = page_to_pfn(ptdev->pm.dummy_latest_flush);
366 		break;
367 
368 	default:
369 		ret = VM_FAULT_SIGBUS;
370 		goto out_unlock;
371 	}
372 
373 	pgprot = vma->vm_page_prot;
374 	if (active)
375 		pgprot = pgprot_noncached(pgprot);
376 
377 	ret = vmf_insert_pfn_prot(vma, vmf->address, pfn, pgprot);
378 
379 out_unlock:
380 	mutex_unlock(&ptdev->pm.mmio_lock);
381 	drm_dev_exit(cookie);
382 	return ret;
383 }
384 
385 static const struct vm_operations_struct panthor_mmio_vm_ops = {
386 	.fault = panthor_mmio_vm_fault,
387 };
388 
389 int panthor_device_mmap_io(struct panthor_device *ptdev, struct vm_area_struct *vma)
390 {
391 	u64 offset = (u64)vma->vm_pgoff << PAGE_SHIFT;
392 
393 	switch (offset) {
394 	case DRM_PANTHOR_USER_FLUSH_ID_MMIO_OFFSET:
395 		if (vma->vm_end - vma->vm_start != PAGE_SIZE ||
396 		    (vma->vm_flags & (VM_WRITE | VM_EXEC)))
397 			return -EINVAL;
398 
399 		break;
400 
401 	default:
402 		return -EINVAL;
403 	}
404 
405 	/* Defer actual mapping to the fault handler. */
406 	vma->vm_private_data = ptdev;
407 	vma->vm_ops = &panthor_mmio_vm_ops;
408 	vm_flags_set(vma,
409 		     VM_IO | VM_DONTCOPY | VM_DONTEXPAND |
410 		     VM_NORESERVE | VM_DONTDUMP | VM_PFNMAP);
411 	return 0;
412 }
413 
414 int panthor_device_resume(struct device *dev)
415 {
416 	struct panthor_device *ptdev = dev_get_drvdata(dev);
417 	int ret, cookie;
418 
419 	if (atomic_read(&ptdev->pm.state) != PANTHOR_DEVICE_PM_STATE_SUSPENDED)
420 		return -EINVAL;
421 
422 	atomic_set(&ptdev->pm.state, PANTHOR_DEVICE_PM_STATE_RESUMING);
423 
424 	ret = clk_prepare_enable(ptdev->clks.core);
425 	if (ret)
426 		goto err_set_suspended;
427 
428 	ret = clk_prepare_enable(ptdev->clks.stacks);
429 	if (ret)
430 		goto err_disable_core_clk;
431 
432 	ret = clk_prepare_enable(ptdev->clks.coregroup);
433 	if (ret)
434 		goto err_disable_stacks_clk;
435 
436 	ret = panthor_devfreq_resume(ptdev);
437 	if (ret)
438 		goto err_disable_coregroup_clk;
439 
440 	if (panthor_device_is_initialized(ptdev) &&
441 	    drm_dev_enter(&ptdev->base, &cookie)) {
442 		panthor_gpu_resume(ptdev);
443 		panthor_mmu_resume(ptdev);
444 		ret = drm_WARN_ON(&ptdev->base, panthor_fw_resume(ptdev));
445 		if (!ret) {
446 			panthor_sched_resume(ptdev);
447 		} else {
448 			panthor_mmu_suspend(ptdev);
449 			panthor_gpu_suspend(ptdev);
450 		}
451 
452 		drm_dev_exit(cookie);
453 
454 		if (ret)
455 			goto err_suspend_devfreq;
456 	}
457 
458 	if (atomic_read(&ptdev->reset.pending))
459 		queue_work(ptdev->reset.wq, &ptdev->reset.work);
460 
461 	/* Clear all IOMEM mappings pointing to this device after we've
462 	 * resumed. This way the fake mappings pointing to the dummy pages
463 	 * are removed and the real iomem mapping will be restored on next
464 	 * access.
465 	 */
466 	mutex_lock(&ptdev->pm.mmio_lock);
467 	unmap_mapping_range(ptdev->base.anon_inode->i_mapping,
468 			    DRM_PANTHOR_USER_MMIO_OFFSET, 0, 1);
469 	atomic_set(&ptdev->pm.state, PANTHOR_DEVICE_PM_STATE_ACTIVE);
470 	mutex_unlock(&ptdev->pm.mmio_lock);
471 	return 0;
472 
473 err_suspend_devfreq:
474 	panthor_devfreq_suspend(ptdev);
475 
476 err_disable_coregroup_clk:
477 	clk_disable_unprepare(ptdev->clks.coregroup);
478 
479 err_disable_stacks_clk:
480 	clk_disable_unprepare(ptdev->clks.stacks);
481 
482 err_disable_core_clk:
483 	clk_disable_unprepare(ptdev->clks.core);
484 
485 err_set_suspended:
486 	atomic_set(&ptdev->pm.state, PANTHOR_DEVICE_PM_STATE_SUSPENDED);
487 	return ret;
488 }
489 
490 int panthor_device_suspend(struct device *dev)
491 {
492 	struct panthor_device *ptdev = dev_get_drvdata(dev);
493 	int ret, cookie;
494 
495 	if (atomic_read(&ptdev->pm.state) != PANTHOR_DEVICE_PM_STATE_ACTIVE)
496 		return -EINVAL;
497 
498 	/* Clear all IOMEM mappings pointing to this device before we
499 	 * shutdown the power-domain and clocks. Failing to do that results
500 	 * in external aborts when the process accesses the iomem region.
501 	 * We change the state and call unmap_mapping_range() with the
502 	 * mmio_lock held to make sure the vm_fault handler won't set up
503 	 * invalid mappings.
504 	 */
505 	mutex_lock(&ptdev->pm.mmio_lock);
506 	atomic_set(&ptdev->pm.state, PANTHOR_DEVICE_PM_STATE_SUSPENDING);
507 	unmap_mapping_range(ptdev->base.anon_inode->i_mapping,
508 			    DRM_PANTHOR_USER_MMIO_OFFSET, 0, 1);
509 	mutex_unlock(&ptdev->pm.mmio_lock);
510 
511 	if (panthor_device_is_initialized(ptdev) &&
512 	    drm_dev_enter(&ptdev->base, &cookie)) {
513 		cancel_work_sync(&ptdev->reset.work);
514 
515 		/* We prepare everything as if we were resetting the GPU.
516 		 * The end of the reset will happen in the resume path though.
517 		 */
518 		panthor_sched_suspend(ptdev);
519 		panthor_fw_suspend(ptdev);
520 		panthor_mmu_suspend(ptdev);
521 		panthor_gpu_suspend(ptdev);
522 		drm_dev_exit(cookie);
523 	}
524 
525 	ret = panthor_devfreq_suspend(ptdev);
526 	if (ret) {
527 		if (panthor_device_is_initialized(ptdev) &&
528 		    drm_dev_enter(&ptdev->base, &cookie)) {
529 			panthor_gpu_resume(ptdev);
530 			panthor_mmu_resume(ptdev);
531 			drm_WARN_ON(&ptdev->base, panthor_fw_resume(ptdev));
532 			panthor_sched_resume(ptdev);
533 			drm_dev_exit(cookie);
534 		}
535 
536 		goto err_set_active;
537 	}
538 
539 	clk_disable_unprepare(ptdev->clks.coregroup);
540 	clk_disable_unprepare(ptdev->clks.stacks);
541 	clk_disable_unprepare(ptdev->clks.core);
542 	atomic_set(&ptdev->pm.state, PANTHOR_DEVICE_PM_STATE_SUSPENDED);
543 	return 0;
544 
545 err_set_active:
546 	/* If something failed and we have to revert back to an
547 	 * active state, we also need to clear the MMIO userspace
548 	 * mappings, so any dumb pages that were mapped while we
549 	 * were trying to suspend gets invalidated.
550 	 */
551 	mutex_lock(&ptdev->pm.mmio_lock);
552 	atomic_set(&ptdev->pm.state, PANTHOR_DEVICE_PM_STATE_ACTIVE);
553 	unmap_mapping_range(ptdev->base.anon_inode->i_mapping,
554 			    DRM_PANTHOR_USER_MMIO_OFFSET, 0, 1);
555 	mutex_unlock(&ptdev->pm.mmio_lock);
556 	return ret;
557 }
558