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