1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2
3 /*
4 * Xen para-virtual DRM device
5 *
6 * Copyright (C) 2016-2018 EPAM Systems Inc.
7 *
8 * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
9 */
10
11 #include <drm/drm_atomic.h>
12 #include <drm/drm_atomic_helper.h>
13 #include <drm/drm_drv.h>
14 #include <drm/drm_fourcc.h>
15 #include <drm/drm_gem.h>
16 #include <drm/drm_gem_framebuffer_helper.h>
17 #include <drm/drm_probe_helper.h>
18 #include <drm/drm_vblank.h>
19
20 #include "xen_drm_front.h"
21 #include "xen_drm_front_conn.h"
22 #include "xen_drm_front_kms.h"
23
24 /*
25 * Timeout in ms to wait for frame done event from the backend:
26 * must be a bit more than IO time-out
27 */
28 #define FRAME_DONE_TO_MS (XEN_DRM_FRONT_WAIT_BACK_MS + 100)
29
30 static struct xen_drm_front_drm_pipeline *
to_xen_drm_pipeline(struct drm_simple_display_pipe * pipe)31 to_xen_drm_pipeline(struct drm_simple_display_pipe *pipe)
32 {
33 return container_of(pipe, struct xen_drm_front_drm_pipeline, pipe);
34 }
35
fb_destroy(struct drm_framebuffer * fb)36 static void fb_destroy(struct drm_framebuffer *fb)
37 {
38 struct xen_drm_front_drm_info *drm_info = fb->dev->dev_private;
39 int idx;
40
41 if (drm_dev_enter(fb->dev, &idx)) {
42 xen_drm_front_fb_detach(drm_info->front_info,
43 xen_drm_front_fb_to_cookie(fb));
44 drm_dev_exit(idx);
45 }
46 drm_gem_fb_destroy(fb);
47 }
48
49 static const struct drm_framebuffer_funcs fb_funcs = {
50 .destroy = fb_destroy,
51 };
52
53 static struct drm_framebuffer *
fb_create(struct drm_device * dev,struct drm_file * filp,const struct drm_mode_fb_cmd2 * mode_cmd)54 fb_create(struct drm_device *dev, struct drm_file *filp,
55 const struct drm_mode_fb_cmd2 *mode_cmd)
56 {
57 struct xen_drm_front_drm_info *drm_info = dev->dev_private;
58 struct drm_framebuffer *fb;
59 struct drm_gem_object *gem_obj;
60 int ret;
61
62 fb = drm_gem_fb_create_with_funcs(dev, filp, mode_cmd, &fb_funcs);
63 if (IS_ERR_OR_NULL(fb))
64 return fb;
65
66 gem_obj = drm_gem_object_lookup(filp, mode_cmd->handles[0]);
67 if (!gem_obj) {
68 DRM_ERROR("Failed to lookup GEM object\n");
69 ret = -ENOENT;
70 goto fail;
71 }
72
73 drm_gem_object_put_unlocked(gem_obj);
74
75 ret = xen_drm_front_fb_attach(drm_info->front_info,
76 xen_drm_front_dbuf_to_cookie(gem_obj),
77 xen_drm_front_fb_to_cookie(fb),
78 fb->width, fb->height,
79 fb->format->format);
80 if (ret < 0) {
81 DRM_ERROR("Back failed to attach FB %p: %d\n", fb, ret);
82 goto fail;
83 }
84
85 return fb;
86
87 fail:
88 drm_gem_fb_destroy(fb);
89 return ERR_PTR(ret);
90 }
91
92 static const struct drm_mode_config_funcs mode_config_funcs = {
93 .fb_create = fb_create,
94 .atomic_check = drm_atomic_helper_check,
95 .atomic_commit = drm_atomic_helper_commit,
96 };
97
send_pending_event(struct xen_drm_front_drm_pipeline * pipeline)98 static void send_pending_event(struct xen_drm_front_drm_pipeline *pipeline)
99 {
100 struct drm_crtc *crtc = &pipeline->pipe.crtc;
101 struct drm_device *dev = crtc->dev;
102 unsigned long flags;
103
104 spin_lock_irqsave(&dev->event_lock, flags);
105 if (pipeline->pending_event)
106 drm_crtc_send_vblank_event(crtc, pipeline->pending_event);
107 pipeline->pending_event = NULL;
108 spin_unlock_irqrestore(&dev->event_lock, flags);
109 }
110
display_enable(struct drm_simple_display_pipe * pipe,struct drm_crtc_state * crtc_state,struct drm_plane_state * plane_state)111 static void display_enable(struct drm_simple_display_pipe *pipe,
112 struct drm_crtc_state *crtc_state,
113 struct drm_plane_state *plane_state)
114 {
115 struct xen_drm_front_drm_pipeline *pipeline =
116 to_xen_drm_pipeline(pipe);
117 struct drm_crtc *crtc = &pipe->crtc;
118 struct drm_framebuffer *fb = plane_state->fb;
119 int ret, idx;
120
121 if (!drm_dev_enter(pipe->crtc.dev, &idx))
122 return;
123
124 ret = xen_drm_front_mode_set(pipeline, crtc->x, crtc->y,
125 fb->width, fb->height,
126 fb->format->cpp[0] * 8,
127 xen_drm_front_fb_to_cookie(fb));
128
129 if (ret) {
130 DRM_ERROR("Failed to enable display: %d\n", ret);
131 pipeline->conn_connected = false;
132 }
133
134 drm_dev_exit(idx);
135 }
136
display_disable(struct drm_simple_display_pipe * pipe)137 static void display_disable(struct drm_simple_display_pipe *pipe)
138 {
139 struct xen_drm_front_drm_pipeline *pipeline =
140 to_xen_drm_pipeline(pipe);
141 int ret = 0, idx;
142
143 if (drm_dev_enter(pipe->crtc.dev, &idx)) {
144 ret = xen_drm_front_mode_set(pipeline, 0, 0, 0, 0, 0,
145 xen_drm_front_fb_to_cookie(NULL));
146 drm_dev_exit(idx);
147 }
148 if (ret)
149 DRM_ERROR("Failed to disable display: %d\n", ret);
150
151 /* Make sure we can restart with enabled connector next time */
152 pipeline->conn_connected = true;
153
154 /* release stalled event if any */
155 send_pending_event(pipeline);
156 }
157
xen_drm_front_kms_on_frame_done(struct xen_drm_front_drm_pipeline * pipeline,u64 fb_cookie)158 void xen_drm_front_kms_on_frame_done(struct xen_drm_front_drm_pipeline *pipeline,
159 u64 fb_cookie)
160 {
161 /*
162 * This runs in interrupt context, e.g. under
163 * drm_info->front_info->io_lock, so we cannot call _sync version
164 * to cancel the work
165 */
166 cancel_delayed_work(&pipeline->pflip_to_worker);
167
168 send_pending_event(pipeline);
169 }
170
pflip_to_worker(struct work_struct * work)171 static void pflip_to_worker(struct work_struct *work)
172 {
173 struct delayed_work *delayed_work = to_delayed_work(work);
174 struct xen_drm_front_drm_pipeline *pipeline =
175 container_of(delayed_work,
176 struct xen_drm_front_drm_pipeline,
177 pflip_to_worker);
178
179 DRM_ERROR("Frame done timed-out, releasing");
180 send_pending_event(pipeline);
181 }
182
display_send_page_flip(struct drm_simple_display_pipe * pipe,struct drm_plane_state * old_plane_state)183 static bool display_send_page_flip(struct drm_simple_display_pipe *pipe,
184 struct drm_plane_state *old_plane_state)
185 {
186 struct drm_plane_state *plane_state =
187 drm_atomic_get_new_plane_state(old_plane_state->state,
188 &pipe->plane);
189
190 /*
191 * If old_plane_state->fb is NULL and plane_state->fb is not,
192 * then this is an atomic commit which will enable display.
193 * If old_plane_state->fb is not NULL and plane_state->fb is,
194 * then this is an atomic commit which will disable display.
195 * Ignore these and do not send page flip as this framebuffer will be
196 * sent to the backend as a part of display_set_config call.
197 */
198 if (old_plane_state->fb && plane_state->fb) {
199 struct xen_drm_front_drm_pipeline *pipeline =
200 to_xen_drm_pipeline(pipe);
201 struct xen_drm_front_drm_info *drm_info = pipeline->drm_info;
202 int ret;
203
204 schedule_delayed_work(&pipeline->pflip_to_worker,
205 msecs_to_jiffies(FRAME_DONE_TO_MS));
206
207 ret = xen_drm_front_page_flip(drm_info->front_info,
208 pipeline->index,
209 xen_drm_front_fb_to_cookie(plane_state->fb));
210 if (ret) {
211 DRM_ERROR("Failed to send page flip request to backend: %d\n", ret);
212
213 pipeline->conn_connected = false;
214 /*
215 * Report the flip not handled, so pending event is
216 * sent, unblocking user-space.
217 */
218 return false;
219 }
220 /*
221 * Signal that page flip was handled, pending event will be sent
222 * on frame done event from the backend.
223 */
224 return true;
225 }
226
227 return false;
228 }
229
display_update(struct drm_simple_display_pipe * pipe,struct drm_plane_state * old_plane_state)230 static void display_update(struct drm_simple_display_pipe *pipe,
231 struct drm_plane_state *old_plane_state)
232 {
233 struct xen_drm_front_drm_pipeline *pipeline =
234 to_xen_drm_pipeline(pipe);
235 struct drm_crtc *crtc = &pipe->crtc;
236 struct drm_pending_vblank_event *event;
237 int idx;
238
239 event = crtc->state->event;
240 if (event) {
241 struct drm_device *dev = crtc->dev;
242 unsigned long flags;
243
244 WARN_ON(pipeline->pending_event);
245
246 spin_lock_irqsave(&dev->event_lock, flags);
247 crtc->state->event = NULL;
248
249 pipeline->pending_event = event;
250 spin_unlock_irqrestore(&dev->event_lock, flags);
251 }
252
253 if (!drm_dev_enter(pipe->crtc.dev, &idx)) {
254 send_pending_event(pipeline);
255 return;
256 }
257
258 /*
259 * Send page flip request to the backend *after* we have event cached
260 * above, so on page flip done event from the backend we can
261 * deliver it and there is no race condition between this code and
262 * event from the backend.
263 * If this is not a page flip, e.g. no flip done event from the backend
264 * is expected, then send now.
265 */
266 if (!display_send_page_flip(pipe, old_plane_state))
267 send_pending_event(pipeline);
268
269 drm_dev_exit(idx);
270 }
271
272 static enum drm_mode_status
display_mode_valid(struct drm_crtc * crtc,const struct drm_display_mode * mode)273 display_mode_valid(struct drm_crtc *crtc, const struct drm_display_mode *mode)
274 {
275 struct xen_drm_front_drm_pipeline *pipeline =
276 container_of(crtc, struct xen_drm_front_drm_pipeline,
277 pipe.crtc);
278
279 if (mode->hdisplay != pipeline->width)
280 return MODE_ERROR;
281
282 if (mode->vdisplay != pipeline->height)
283 return MODE_ERROR;
284
285 return MODE_OK;
286 }
287
288 static const struct drm_simple_display_pipe_funcs display_funcs = {
289 .mode_valid = display_mode_valid,
290 .enable = display_enable,
291 .disable = display_disable,
292 .prepare_fb = drm_gem_fb_simple_display_pipe_prepare_fb,
293 .update = display_update,
294 };
295
display_pipe_init(struct xen_drm_front_drm_info * drm_info,int index,struct xen_drm_front_cfg_connector * cfg,struct xen_drm_front_drm_pipeline * pipeline)296 static int display_pipe_init(struct xen_drm_front_drm_info *drm_info,
297 int index, struct xen_drm_front_cfg_connector *cfg,
298 struct xen_drm_front_drm_pipeline *pipeline)
299 {
300 struct drm_device *dev = drm_info->drm_dev;
301 const u32 *formats;
302 int format_count;
303 int ret;
304
305 pipeline->drm_info = drm_info;
306 pipeline->index = index;
307 pipeline->height = cfg->height;
308 pipeline->width = cfg->width;
309
310 INIT_DELAYED_WORK(&pipeline->pflip_to_worker, pflip_to_worker);
311
312 ret = xen_drm_front_conn_init(drm_info, &pipeline->conn);
313 if (ret)
314 return ret;
315
316 formats = xen_drm_front_conn_get_formats(&format_count);
317
318 return drm_simple_display_pipe_init(dev, &pipeline->pipe,
319 &display_funcs, formats,
320 format_count, NULL,
321 &pipeline->conn);
322 }
323
xen_drm_front_kms_init(struct xen_drm_front_drm_info * drm_info)324 int xen_drm_front_kms_init(struct xen_drm_front_drm_info *drm_info)
325 {
326 struct drm_device *dev = drm_info->drm_dev;
327 int i, ret;
328
329 drm_mode_config_init(dev);
330
331 dev->mode_config.min_width = 0;
332 dev->mode_config.min_height = 0;
333 dev->mode_config.max_width = 4095;
334 dev->mode_config.max_height = 2047;
335 dev->mode_config.funcs = &mode_config_funcs;
336
337 for (i = 0; i < drm_info->front_info->cfg.num_connectors; i++) {
338 struct xen_drm_front_cfg_connector *cfg =
339 &drm_info->front_info->cfg.connectors[i];
340 struct xen_drm_front_drm_pipeline *pipeline =
341 &drm_info->pipeline[i];
342
343 ret = display_pipe_init(drm_info, i, cfg, pipeline);
344 if (ret) {
345 drm_mode_config_cleanup(dev);
346 return ret;
347 }
348 }
349
350 drm_mode_config_reset(dev);
351 drm_kms_helper_poll_init(dev);
352 return 0;
353 }
354
xen_drm_front_kms_fini(struct xen_drm_front_drm_info * drm_info)355 void xen_drm_front_kms_fini(struct xen_drm_front_drm_info *drm_info)
356 {
357 int i;
358
359 for (i = 0; i < drm_info->front_info->cfg.num_connectors; i++) {
360 struct xen_drm_front_drm_pipeline *pipeline =
361 &drm_info->pipeline[i];
362
363 cancel_delayed_work_sync(&pipeline->pflip_to_worker);
364
365 send_pending_event(pipeline);
366 }
367 }
368
