xref: /openbmc/linux/drivers/gpu/drm/gud/gud_pipe.c (revision b1c3d2be)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright 2020 Noralf Trønnes
4  */
5 
6 #include <linux/lz4.h>
7 #include <linux/usb.h>
8 #include <linux/workqueue.h>
9 
10 #include <drm/drm_atomic.h>
11 #include <drm/drm_connector.h>
12 #include <drm/drm_damage_helper.h>
13 #include <drm/drm_drv.h>
14 #include <drm/drm_format_helper.h>
15 #include <drm/drm_fourcc.h>
16 #include <drm/drm_framebuffer.h>
17 #include <drm/drm_gem.h>
18 #include <drm/drm_gem_framebuffer_helper.h>
19 #include <drm/drm_print.h>
20 #include <drm/drm_rect.h>
21 #include <drm/drm_simple_kms_helper.h>
22 #include <drm/gud.h>
23 
24 #include "gud_internal.h"
25 
26 /*
27  * Some userspace rendering loops runs all displays in the same loop.
28  * This means that a fast display will have to wait for a slow one.
29  * For this reason gud does flushing asynchronous by default.
30  * The down side is that in e.g. a single display setup userspace thinks
31  * the display is insanely fast since the driver reports back immediately
32  * that the flush/pageflip is done. This wastes CPU and power.
33  * Such users might want to set this module parameter to false.
34  */
35 static bool gud_async_flush = true;
36 module_param_named(async_flush, gud_async_flush, bool, 0644);
37 MODULE_PARM_DESC(async_flush, "Enable asynchronous flushing [default=true]");
38 
39 /*
40  * FIXME: The driver is probably broken on Big Endian machines.
41  * See discussion:
42  * https://lore.kernel.org/dri-devel/CAKb7UvihLX0hgBOP3VBG7O+atwZcUVCPVuBdfmDMpg0NjXe-cQ@mail.gmail.com/
43  */
44 
45 static bool gud_is_big_endian(void)
46 {
47 #if defined(__BIG_ENDIAN)
48 	return true;
49 #else
50 	return false;
51 #endif
52 }
53 
54 static size_t gud_xrgb8888_to_r124(u8 *dst, const struct drm_format_info *format,
55 				   void *src, struct drm_framebuffer *fb,
56 				   struct drm_rect *rect)
57 {
58 	unsigned int block_width = drm_format_info_block_width(format, 0);
59 	unsigned int bits_per_pixel = 8 / block_width;
60 	unsigned int x, y, width, height;
61 	u8 pix, *pix8, *block = dst; /* Assign to silence compiler warning */
62 	struct iosys_map dst_map, vmap;
63 	size_t len;
64 	void *buf;
65 
66 	WARN_ON_ONCE(format->char_per_block[0] != 1);
67 
68 	/* Start on a byte boundary */
69 	rect->x1 = ALIGN_DOWN(rect->x1, block_width);
70 	width = drm_rect_width(rect);
71 	height = drm_rect_height(rect);
72 	len = drm_format_info_min_pitch(format, 0, width) * height;
73 
74 	buf = kmalloc(width * height, GFP_KERNEL);
75 	if (!buf)
76 		return 0;
77 
78 	iosys_map_set_vaddr(&dst_map, buf);
79 	iosys_map_set_vaddr(&vmap, src);
80 	drm_fb_xrgb8888_to_gray8(&dst_map, NULL, &vmap, fb, rect);
81 	pix8 = buf;
82 
83 	for (y = 0; y < height; y++) {
84 		for (x = 0; x < width; x++) {
85 			unsigned int pixpos = x % block_width; /* within byte from the left */
86 			unsigned int pixshift = (block_width - pixpos - 1) * bits_per_pixel;
87 
88 			if (!pixpos) {
89 				block = dst++;
90 				*block = 0;
91 			}
92 
93 			pix = (*pix8++) >> (8 - bits_per_pixel);
94 			*block |= pix << pixshift;
95 		}
96 	}
97 
98 	kfree(buf);
99 
100 	return len;
101 }
102 
103 static size_t gud_xrgb8888_to_color(u8 *dst, const struct drm_format_info *format,
104 				    void *src, struct drm_framebuffer *fb,
105 				    struct drm_rect *rect)
106 {
107 	unsigned int block_width = drm_format_info_block_width(format, 0);
108 	unsigned int bits_per_pixel = 8 / block_width;
109 	u8 r, g, b, pix, *block = dst; /* Assign to silence compiler warning */
110 	unsigned int x, y, width;
111 	__le32 *sbuf32;
112 	u32 pix32;
113 	size_t len;
114 
115 	/* Start on a byte boundary */
116 	rect->x1 = ALIGN_DOWN(rect->x1, block_width);
117 	width = drm_rect_width(rect);
118 	len = drm_format_info_min_pitch(format, 0, width) * drm_rect_height(rect);
119 
120 	for (y = rect->y1; y < rect->y2; y++) {
121 		sbuf32 = src + (y * fb->pitches[0]);
122 		sbuf32 += rect->x1;
123 
124 		for (x = 0; x < width; x++) {
125 			unsigned int pixpos = x % block_width; /* within byte from the left */
126 			unsigned int pixshift = (block_width - pixpos - 1) * bits_per_pixel;
127 
128 			if (!pixpos) {
129 				block = dst++;
130 				*block = 0;
131 			}
132 
133 			pix32 = le32_to_cpu(*sbuf32++);
134 			r = pix32 >> 16;
135 			g = pix32 >> 8;
136 			b = pix32;
137 
138 			switch (format->format) {
139 			case GUD_DRM_FORMAT_XRGB1111:
140 				pix = ((r >> 7) << 2) | ((g >> 7) << 1) | (b >> 7);
141 				break;
142 			default:
143 				WARN_ON_ONCE(1);
144 				return len;
145 			}
146 
147 			*block |= pix << pixshift;
148 		}
149 	}
150 
151 	return len;
152 }
153 
154 static int gud_prep_flush(struct gud_device *gdrm, struct drm_framebuffer *fb,
155 			  const struct drm_format_info *format, struct drm_rect *rect,
156 			  struct gud_set_buffer_req *req)
157 {
158 	struct dma_buf_attachment *import_attach = fb->obj[0]->import_attach;
159 	u8 compression = gdrm->compression;
160 	struct iosys_map map[DRM_FORMAT_MAX_PLANES];
161 	struct iosys_map map_data[DRM_FORMAT_MAX_PLANES];
162 	struct iosys_map dst;
163 	void *vaddr, *buf;
164 	size_t pitch, len;
165 	int ret = 0;
166 
167 	pitch = drm_format_info_min_pitch(format, 0, drm_rect_width(rect));
168 	len = pitch * drm_rect_height(rect);
169 	if (len > gdrm->bulk_len)
170 		return -E2BIG;
171 
172 	ret = drm_gem_fb_vmap(fb, map, map_data);
173 	if (ret)
174 		return ret;
175 
176 	vaddr = map_data[0].vaddr;
177 
178 	ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE);
179 	if (ret)
180 		goto vunmap;
181 retry:
182 	if (compression)
183 		buf = gdrm->compress_buf;
184 	else
185 		buf = gdrm->bulk_buf;
186 	iosys_map_set_vaddr(&dst, buf);
187 
188 	/*
189 	 * Imported buffers are assumed to be write-combined and thus uncached
190 	 * with slow reads (at least on ARM).
191 	 */
192 	if (format != fb->format) {
193 		if (format->format == GUD_DRM_FORMAT_R1) {
194 			len = gud_xrgb8888_to_r124(buf, format, vaddr, fb, rect);
195 			if (!len) {
196 				ret = -ENOMEM;
197 				goto end_cpu_access;
198 			}
199 		} else if (format->format == DRM_FORMAT_R8) {
200 			drm_fb_xrgb8888_to_gray8(&dst, NULL, map_data, fb, rect);
201 		} else if (format->format == DRM_FORMAT_RGB332) {
202 			drm_fb_xrgb8888_to_rgb332(&dst, NULL, map_data, fb, rect);
203 		} else if (format->format == DRM_FORMAT_RGB565) {
204 			drm_fb_xrgb8888_to_rgb565(&dst, NULL, map_data, fb, rect,
205 						  gud_is_big_endian());
206 		} else if (format->format == DRM_FORMAT_RGB888) {
207 			drm_fb_xrgb8888_to_rgb888(&dst, NULL, map_data, fb, rect);
208 		} else {
209 			len = gud_xrgb8888_to_color(buf, format, vaddr, fb, rect);
210 		}
211 	} else if (gud_is_big_endian() && format->cpp[0] > 1) {
212 		drm_fb_swab(&dst, NULL, map_data, fb, rect, !import_attach);
213 	} else if (compression && !import_attach && pitch == fb->pitches[0]) {
214 		/* can compress directly from the framebuffer */
215 		buf = vaddr + rect->y1 * pitch;
216 	} else {
217 		drm_fb_memcpy(&dst, NULL, map_data, fb, rect);
218 	}
219 
220 	memset(req, 0, sizeof(*req));
221 	req->x = cpu_to_le32(rect->x1);
222 	req->y = cpu_to_le32(rect->y1);
223 	req->width = cpu_to_le32(drm_rect_width(rect));
224 	req->height = cpu_to_le32(drm_rect_height(rect));
225 	req->length = cpu_to_le32(len);
226 
227 	if (compression & GUD_COMPRESSION_LZ4) {
228 		int complen;
229 
230 		complen = LZ4_compress_default(buf, gdrm->bulk_buf, len, len, gdrm->lz4_comp_mem);
231 		if (complen <= 0) {
232 			compression = 0;
233 			goto retry;
234 		}
235 
236 		req->compression = GUD_COMPRESSION_LZ4;
237 		req->compressed_length = cpu_to_le32(complen);
238 	}
239 
240 end_cpu_access:
241 	drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE);
242 vunmap:
243 	drm_gem_fb_vunmap(fb, map);
244 
245 	return ret;
246 }
247 
248 struct gud_usb_bulk_context {
249 	struct timer_list timer;
250 	struct usb_sg_request sgr;
251 };
252 
253 static void gud_usb_bulk_timeout(struct timer_list *t)
254 {
255 	struct gud_usb_bulk_context *ctx = from_timer(ctx, t, timer);
256 
257 	usb_sg_cancel(&ctx->sgr);
258 }
259 
260 static int gud_usb_bulk(struct gud_device *gdrm, size_t len)
261 {
262 	struct gud_usb_bulk_context ctx;
263 	int ret;
264 
265 	ret = usb_sg_init(&ctx.sgr, gud_to_usb_device(gdrm), gdrm->bulk_pipe, 0,
266 			  gdrm->bulk_sgt.sgl, gdrm->bulk_sgt.nents, len, GFP_KERNEL);
267 	if (ret)
268 		return ret;
269 
270 	timer_setup_on_stack(&ctx.timer, gud_usb_bulk_timeout, 0);
271 	mod_timer(&ctx.timer, jiffies + msecs_to_jiffies(3000));
272 
273 	usb_sg_wait(&ctx.sgr);
274 
275 	if (!del_timer_sync(&ctx.timer))
276 		ret = -ETIMEDOUT;
277 	else if (ctx.sgr.status < 0)
278 		ret = ctx.sgr.status;
279 	else if (ctx.sgr.bytes != len)
280 		ret = -EIO;
281 
282 	destroy_timer_on_stack(&ctx.timer);
283 
284 	return ret;
285 }
286 
287 static int gud_flush_rect(struct gud_device *gdrm, struct drm_framebuffer *fb,
288 			  const struct drm_format_info *format, struct drm_rect *rect)
289 {
290 	struct gud_set_buffer_req req;
291 	size_t len, trlen;
292 	int ret;
293 
294 	drm_dbg(&gdrm->drm, "Flushing [FB:%d] " DRM_RECT_FMT "\n", fb->base.id, DRM_RECT_ARG(rect));
295 
296 	ret = gud_prep_flush(gdrm, fb, format, rect, &req);
297 	if (ret)
298 		return ret;
299 
300 	len = le32_to_cpu(req.length);
301 
302 	if (req.compression)
303 		trlen = le32_to_cpu(req.compressed_length);
304 	else
305 		trlen = len;
306 
307 	gdrm->stats_length += len;
308 	/* Did it wrap around? */
309 	if (gdrm->stats_length <= len && gdrm->stats_actual_length) {
310 		gdrm->stats_length = len;
311 		gdrm->stats_actual_length = 0;
312 	}
313 	gdrm->stats_actual_length += trlen;
314 
315 	if (!(gdrm->flags & GUD_DISPLAY_FLAG_FULL_UPDATE) || gdrm->prev_flush_failed) {
316 		ret = gud_usb_set(gdrm, GUD_REQ_SET_BUFFER, 0, &req, sizeof(req));
317 		if (ret)
318 			return ret;
319 	}
320 
321 	ret = gud_usb_bulk(gdrm, trlen);
322 	if (ret)
323 		gdrm->stats_num_errors++;
324 
325 	return ret;
326 }
327 
328 void gud_clear_damage(struct gud_device *gdrm)
329 {
330 	gdrm->damage.x1 = INT_MAX;
331 	gdrm->damage.y1 = INT_MAX;
332 	gdrm->damage.x2 = 0;
333 	gdrm->damage.y2 = 0;
334 }
335 
336 static void gud_add_damage(struct gud_device *gdrm, struct drm_rect *damage)
337 {
338 	gdrm->damage.x1 = min(gdrm->damage.x1, damage->x1);
339 	gdrm->damage.y1 = min(gdrm->damage.y1, damage->y1);
340 	gdrm->damage.x2 = max(gdrm->damage.x2, damage->x2);
341 	gdrm->damage.y2 = max(gdrm->damage.y2, damage->y2);
342 }
343 
344 static void gud_retry_failed_flush(struct gud_device *gdrm, struct drm_framebuffer *fb,
345 				   struct drm_rect *damage)
346 {
347 	/*
348 	 * pipe_update waits for the worker when the display mode is going to change.
349 	 * This ensures that the width and height is still the same making it safe to
350 	 * add back the damage.
351 	 */
352 
353 	mutex_lock(&gdrm->damage_lock);
354 	if (!gdrm->fb) {
355 		drm_framebuffer_get(fb);
356 		gdrm->fb = fb;
357 	}
358 	gud_add_damage(gdrm, damage);
359 	mutex_unlock(&gdrm->damage_lock);
360 
361 	/* Retry only once to avoid a possible storm in case of continues errors. */
362 	if (!gdrm->prev_flush_failed)
363 		queue_work(system_long_wq, &gdrm->work);
364 	gdrm->prev_flush_failed = true;
365 }
366 
367 void gud_flush_work(struct work_struct *work)
368 {
369 	struct gud_device *gdrm = container_of(work, struct gud_device, work);
370 	const struct drm_format_info *format;
371 	struct drm_framebuffer *fb;
372 	struct drm_rect damage;
373 	unsigned int i, lines;
374 	int idx, ret = 0;
375 	size_t pitch;
376 
377 	if (!drm_dev_enter(&gdrm->drm, &idx))
378 		return;
379 
380 	mutex_lock(&gdrm->damage_lock);
381 	fb = gdrm->fb;
382 	gdrm->fb = NULL;
383 	damage = gdrm->damage;
384 	gud_clear_damage(gdrm);
385 	mutex_unlock(&gdrm->damage_lock);
386 
387 	if (!fb)
388 		goto out;
389 
390 	format = fb->format;
391 	if (format->format == DRM_FORMAT_XRGB8888 && gdrm->xrgb8888_emulation_format)
392 		format = gdrm->xrgb8888_emulation_format;
393 
394 	/* Split update if it's too big */
395 	pitch = drm_format_info_min_pitch(format, 0, drm_rect_width(&damage));
396 	lines = drm_rect_height(&damage);
397 
398 	if (gdrm->bulk_len < lines * pitch)
399 		lines = gdrm->bulk_len / pitch;
400 
401 	for (i = 0; i < DIV_ROUND_UP(drm_rect_height(&damage), lines); i++) {
402 		struct drm_rect rect = damage;
403 
404 		rect.y1 += i * lines;
405 		rect.y2 = min_t(u32, rect.y1 + lines, damage.y2);
406 
407 		ret = gud_flush_rect(gdrm, fb, format, &rect);
408 		if (ret) {
409 			if (ret != -ENODEV && ret != -ECONNRESET &&
410 			    ret != -ESHUTDOWN && ret != -EPROTO) {
411 				bool prev_flush_failed = gdrm->prev_flush_failed;
412 
413 				gud_retry_failed_flush(gdrm, fb, &damage);
414 				if (!prev_flush_failed)
415 					dev_err_ratelimited(fb->dev->dev,
416 							    "Failed to flush framebuffer: error=%d\n", ret);
417 			}
418 			break;
419 		}
420 
421 		gdrm->prev_flush_failed = false;
422 	}
423 
424 	drm_framebuffer_put(fb);
425 out:
426 	drm_dev_exit(idx);
427 }
428 
429 static void gud_fb_queue_damage(struct gud_device *gdrm, struct drm_framebuffer *fb,
430 				struct drm_rect *damage)
431 {
432 	struct drm_framebuffer *old_fb = NULL;
433 
434 	mutex_lock(&gdrm->damage_lock);
435 
436 	if (fb != gdrm->fb) {
437 		old_fb = gdrm->fb;
438 		drm_framebuffer_get(fb);
439 		gdrm->fb = fb;
440 	}
441 
442 	gud_add_damage(gdrm, damage);
443 
444 	mutex_unlock(&gdrm->damage_lock);
445 
446 	queue_work(system_long_wq, &gdrm->work);
447 
448 	if (old_fb)
449 		drm_framebuffer_put(old_fb);
450 }
451 
452 int gud_pipe_check(struct drm_simple_display_pipe *pipe,
453 		   struct drm_plane_state *new_plane_state,
454 		   struct drm_crtc_state *new_crtc_state)
455 {
456 	struct gud_device *gdrm = to_gud_device(pipe->crtc.dev);
457 	struct drm_plane_state *old_plane_state = pipe->plane.state;
458 	const struct drm_display_mode *mode = &new_crtc_state->mode;
459 	struct drm_atomic_state *state = new_plane_state->state;
460 	struct drm_framebuffer *old_fb = old_plane_state->fb;
461 	struct drm_connector_state *connector_state = NULL;
462 	struct drm_framebuffer *fb = new_plane_state->fb;
463 	const struct drm_format_info *format = fb->format;
464 	struct drm_connector *connector;
465 	unsigned int i, num_properties;
466 	struct gud_state_req *req;
467 	int idx, ret;
468 	size_t len;
469 
470 	if (WARN_ON_ONCE(!fb))
471 		return -EINVAL;
472 
473 	if (old_plane_state->rotation != new_plane_state->rotation)
474 		new_crtc_state->mode_changed = true;
475 
476 	if (old_fb && old_fb->format != format)
477 		new_crtc_state->mode_changed = true;
478 
479 	if (!new_crtc_state->mode_changed && !new_crtc_state->connectors_changed)
480 		return 0;
481 
482 	/* Only one connector is supported */
483 	if (hweight32(new_crtc_state->connector_mask) != 1)
484 		return -EINVAL;
485 
486 	if (format->format == DRM_FORMAT_XRGB8888 && gdrm->xrgb8888_emulation_format)
487 		format = gdrm->xrgb8888_emulation_format;
488 
489 	for_each_new_connector_in_state(state, connector, connector_state, i) {
490 		if (connector_state->crtc)
491 			break;
492 	}
493 
494 	/*
495 	 * DRM_IOCTL_MODE_OBJ_SETPROPERTY on the rotation property will not have
496 	 * the connector included in the state.
497 	 */
498 	if (!connector_state) {
499 		struct drm_connector_list_iter conn_iter;
500 
501 		drm_connector_list_iter_begin(pipe->crtc.dev, &conn_iter);
502 		drm_for_each_connector_iter(connector, &conn_iter) {
503 			if (connector->state->crtc) {
504 				connector_state = connector->state;
505 				break;
506 			}
507 		}
508 		drm_connector_list_iter_end(&conn_iter);
509 	}
510 
511 	if (WARN_ON_ONCE(!connector_state))
512 		return -ENOENT;
513 
514 	len = struct_size(req, properties,
515 			  GUD_PROPERTIES_MAX_NUM + GUD_CONNECTOR_PROPERTIES_MAX_NUM);
516 	req = kzalloc(len, GFP_KERNEL);
517 	if (!req)
518 		return -ENOMEM;
519 
520 	gud_from_display_mode(&req->mode, mode);
521 
522 	req->format = gud_from_fourcc(format->format);
523 	if (WARN_ON_ONCE(!req->format)) {
524 		ret = -EINVAL;
525 		goto out;
526 	}
527 
528 	req->connector = drm_connector_index(connector_state->connector);
529 
530 	ret = gud_connector_fill_properties(connector_state, req->properties);
531 	if (ret < 0)
532 		goto out;
533 
534 	num_properties = ret;
535 	for (i = 0; i < gdrm->num_properties; i++) {
536 		u16 prop = gdrm->properties[i];
537 		u64 val;
538 
539 		switch (prop) {
540 		case GUD_PROPERTY_ROTATION:
541 			/* DRM UAPI matches the protocol so use value directly */
542 			val = new_plane_state->rotation;
543 			break;
544 		default:
545 			WARN_ON_ONCE(1);
546 			ret = -EINVAL;
547 			goto out;
548 		}
549 
550 		req->properties[num_properties + i].prop = cpu_to_le16(prop);
551 		req->properties[num_properties + i].val = cpu_to_le64(val);
552 		num_properties++;
553 	}
554 
555 	if (drm_dev_enter(fb->dev, &idx)) {
556 		len = struct_size(req, properties, num_properties);
557 		ret = gud_usb_set(gdrm, GUD_REQ_SET_STATE_CHECK, 0, req, len);
558 		drm_dev_exit(idx);
559 	}  else {
560 		ret = -ENODEV;
561 	}
562 out:
563 	kfree(req);
564 
565 	return ret;
566 }
567 
568 void gud_pipe_update(struct drm_simple_display_pipe *pipe,
569 		     struct drm_plane_state *old_state)
570 {
571 	struct drm_device *drm = pipe->crtc.dev;
572 	struct gud_device *gdrm = to_gud_device(drm);
573 	struct drm_plane_state *state = pipe->plane.state;
574 	struct drm_framebuffer *fb = state->fb;
575 	struct drm_crtc *crtc = &pipe->crtc;
576 	struct drm_rect damage;
577 	int idx;
578 
579 	if (crtc->state->mode_changed || !crtc->state->enable) {
580 		cancel_work_sync(&gdrm->work);
581 		mutex_lock(&gdrm->damage_lock);
582 		if (gdrm->fb) {
583 			drm_framebuffer_put(gdrm->fb);
584 			gdrm->fb = NULL;
585 		}
586 		gud_clear_damage(gdrm);
587 		mutex_unlock(&gdrm->damage_lock);
588 	}
589 
590 	if (!drm_dev_enter(drm, &idx))
591 		return;
592 
593 	if (!old_state->fb)
594 		gud_usb_set_u8(gdrm, GUD_REQ_SET_CONTROLLER_ENABLE, 1);
595 
596 	if (fb && (crtc->state->mode_changed || crtc->state->connectors_changed))
597 		gud_usb_set(gdrm, GUD_REQ_SET_STATE_COMMIT, 0, NULL, 0);
598 
599 	if (crtc->state->active_changed)
600 		gud_usb_set_u8(gdrm, GUD_REQ_SET_DISPLAY_ENABLE, crtc->state->active);
601 
602 	if (drm_atomic_helper_damage_merged(old_state, state, &damage)) {
603 		if (gdrm->flags & GUD_DISPLAY_FLAG_FULL_UPDATE)
604 			drm_rect_init(&damage, 0, 0, fb->width, fb->height);
605 		gud_fb_queue_damage(gdrm, fb, &damage);
606 		if (!gud_async_flush)
607 			flush_work(&gdrm->work);
608 	}
609 
610 	if (!crtc->state->enable)
611 		gud_usb_set_u8(gdrm, GUD_REQ_SET_CONTROLLER_ENABLE, 0);
612 
613 	drm_dev_exit(idx);
614 }
615