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
gud_is_big_endian(void)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
gud_xrgb8888_to_r124(u8 * dst,const struct drm_format_info * format,void * src,struct drm_framebuffer * fb,struct drm_rect * rect)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
gud_xrgb8888_to_color(u8 * dst,const struct drm_format_info * format,void * src,struct drm_framebuffer * fb,struct drm_rect * rect)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
gud_prep_flush(struct gud_device * gdrm,struct drm_framebuffer * fb,const struct drm_format_info * format,struct drm_rect * rect,struct gud_set_buffer_req * req)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
gud_usb_bulk_timeout(struct timer_list * t)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
gud_usb_bulk(struct gud_device * gdrm,size_t len)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
gud_flush_rect(struct gud_device * gdrm,struct drm_framebuffer * fb,const struct drm_format_info * format,struct drm_rect * rect)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
gud_clear_damage(struct gud_device * gdrm)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
gud_add_damage(struct gud_device * gdrm,struct drm_rect * damage)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
gud_retry_failed_flush(struct gud_device * gdrm,struct drm_framebuffer * fb,struct drm_rect * damage)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
gud_flush_work(struct work_struct * work)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
gud_fb_queue_damage(struct gud_device * gdrm,struct drm_framebuffer * fb,struct drm_rect * damage)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
gud_pipe_check(struct drm_simple_display_pipe * pipe,struct drm_plane_state * new_plane_state,struct drm_crtc_state * new_crtc_state)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
gud_pipe_update(struct drm_simple_display_pipe * pipe,struct drm_plane_state * old_state)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