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_framebuffer.h>
16#include <drm/drm_gem.h>
17#include <drm/drm_gem_atomic_helper.h>
18#include <drm/drm_gem_framebuffer_helper.h>
19#include <drm/drm_print.h>
20#include <drm/drm_probe_helper.h>
21#include <drm/drm_vblank.h>
22
23#include "xen_drm_front.h"
24#include "xen_drm_front_conn.h"
25#include "xen_drm_front_kms.h"
26
27/*
28 * Timeout in ms to wait for frame done event from the backend:
29 * must be a bit more than IO time-out
30 */
31#define FRAME_DONE_TO_MS (XEN_DRM_FRONT_WAIT_BACK_MS + 100)
32
33static struct xen_drm_front_drm_pipeline *
34to_xen_drm_pipeline(struct drm_simple_display_pipe *pipe)
35{
36 return container_of(pipe, struct xen_drm_front_drm_pipeline, pipe);
37}
38
39static void fb_destroy(struct drm_framebuffer *fb)
40{
41 struct xen_drm_front_drm_info *drm_info = fb->dev->dev_private;
42 int idx;
43
44 if (drm_dev_enter(dev: fb->dev, idx: &idx)) {
45 xen_drm_front_fb_detach(front_info: drm_info->front_info,
46 fb_cookie: xen_drm_front_fb_to_cookie(fb));
47 drm_dev_exit(idx);
48 }
49 drm_gem_fb_destroy(fb);
50}
51
52static const struct drm_framebuffer_funcs fb_funcs = {
53 .destroy = fb_destroy,
54};
55
56static struct drm_framebuffer *
57fb_create(struct drm_device *dev, struct drm_file *filp,
58 const struct drm_format_info *info,
59 const struct drm_mode_fb_cmd2 *mode_cmd)
60{
61 struct xen_drm_front_drm_info *drm_info = dev->dev_private;
62 struct drm_framebuffer *fb;
63 struct drm_gem_object *gem_obj;
64 int ret;
65
66 fb = drm_gem_fb_create_with_funcs(dev, file: filp, info, mode_cmd, funcs: &fb_funcs);
67 if (IS_ERR(ptr: fb))
68 return fb;
69
70 gem_obj = fb->obj[0];
71
72 ret = xen_drm_front_fb_attach(front_info: drm_info->front_info,
73 dbuf_cookie: xen_drm_front_dbuf_to_cookie(gem_obj),
74 fb_cookie: xen_drm_front_fb_to_cookie(fb),
75 width: fb->width, height: fb->height,
76 pixel_format: fb->format->format);
77 if (ret < 0) {
78 DRM_ERROR("Back failed to attach FB %p: %d\n", fb, ret);
79 goto fail;
80 }
81
82 return fb;
83
84fail:
85 drm_gem_fb_destroy(fb);
86 return ERR_PTR(error: ret);
87}
88
89static const struct drm_mode_config_funcs mode_config_funcs = {
90 .fb_create = fb_create,
91 .atomic_check = drm_atomic_helper_check,
92 .atomic_commit = drm_atomic_helper_commit,
93};
94
95static void send_pending_event(struct xen_drm_front_drm_pipeline *pipeline)
96{
97 struct drm_crtc *crtc = &pipeline->pipe.crtc;
98 struct drm_device *dev = crtc->dev;
99 unsigned long flags;
100
101 spin_lock_irqsave(&dev->event_lock, flags);
102 if (pipeline->pending_event)
103 drm_crtc_send_vblank_event(crtc, e: pipeline->pending_event);
104 pipeline->pending_event = NULL;
105 spin_unlock_irqrestore(lock: &dev->event_lock, flags);
106}
107
108static void display_enable(struct drm_simple_display_pipe *pipe,
109 struct drm_crtc_state *crtc_state,
110 struct drm_plane_state *plane_state)
111{
112 struct xen_drm_front_drm_pipeline *pipeline =
113 to_xen_drm_pipeline(pipe);
114 struct drm_crtc *crtc = &pipe->crtc;
115 struct drm_framebuffer *fb = plane_state->fb;
116 int ret, idx;
117
118 if (!drm_dev_enter(dev: pipe->crtc.dev, idx: &idx))
119 return;
120
121 ret = xen_drm_front_mode_set(pipeline, x: crtc->x, y: crtc->y,
122 width: fb->width, height: fb->height,
123 bpp: fb->format->cpp[0] * 8,
124 fb_cookie: xen_drm_front_fb_to_cookie(fb));
125
126 if (ret) {
127 DRM_ERROR("Failed to enable display: %d\n", ret);
128 pipeline->conn_connected = false;
129 }
130
131 drm_dev_exit(idx);
132}
133
134static void display_disable(struct drm_simple_display_pipe *pipe)
135{
136 struct xen_drm_front_drm_pipeline *pipeline =
137 to_xen_drm_pipeline(pipe);
138 int ret = 0, idx;
139
140 if (drm_dev_enter(dev: pipe->crtc.dev, idx: &idx)) {
141 ret = xen_drm_front_mode_set(pipeline, x: 0, y: 0, width: 0, height: 0, bpp: 0,
142 fb_cookie: xen_drm_front_fb_to_cookie(NULL));
143 drm_dev_exit(idx);
144 }
145 if (ret)
146 DRM_ERROR("Failed to disable display: %d\n", ret);
147
148 /* Make sure we can restart with enabled connector next time */
149 pipeline->conn_connected = true;
150
151 /* release stalled event if any */
152 send_pending_event(pipeline);
153}
154
155void xen_drm_front_kms_on_frame_done(struct xen_drm_front_drm_pipeline *pipeline,
156 u64 fb_cookie)
157{
158 /*
159 * This runs in interrupt context, e.g. under
160 * drm_info->front_info->io_lock, so we cannot call _sync version
161 * to cancel the work
162 */
163 cancel_delayed_work(dwork: &pipeline->pflip_to_worker);
164
165 send_pending_event(pipeline);
166}
167
168static void pflip_to_worker(struct work_struct *work)
169{
170 struct delayed_work *delayed_work = to_delayed_work(work);
171 struct xen_drm_front_drm_pipeline *pipeline =
172 container_of(delayed_work,
173 struct xen_drm_front_drm_pipeline,
174 pflip_to_worker);
175
176 DRM_ERROR("Frame done timed-out, releasing");
177 send_pending_event(pipeline);
178}
179
180static bool display_send_page_flip(struct drm_simple_display_pipe *pipe,
181 struct drm_plane_state *old_plane_state)
182{
183 struct drm_plane_state *plane_state =
184 drm_atomic_get_new_plane_state(state: old_plane_state->state,
185 plane: &pipe->plane);
186
187 /*
188 * If old_plane_state->fb is NULL and plane_state->fb is not,
189 * then this is an atomic commit which will enable display.
190 * If old_plane_state->fb is not NULL and plane_state->fb is,
191 * then this is an atomic commit which will disable display.
192 * Ignore these and do not send page flip as this framebuffer will be
193 * sent to the backend as a part of display_set_config call.
194 */
195 if (old_plane_state->fb && plane_state->fb) {
196 struct xen_drm_front_drm_pipeline *pipeline =
197 to_xen_drm_pipeline(pipe);
198 struct xen_drm_front_drm_info *drm_info = pipeline->drm_info;
199 int ret;
200
201 schedule_delayed_work(dwork: &pipeline->pflip_to_worker,
202 delay: msecs_to_jiffies(FRAME_DONE_TO_MS));
203
204 ret = xen_drm_front_page_flip(front_info: drm_info->front_info,
205 conn_idx: pipeline->index,
206 fb_cookie: xen_drm_front_fb_to_cookie(fb: plane_state->fb));
207 if (ret) {
208 DRM_ERROR("Failed to send page flip request to backend: %d\n", ret);
209
210 pipeline->conn_connected = false;
211 /*
212 * Report the flip not handled, so pending event is
213 * sent, unblocking user-space.
214 */
215 return false;
216 }
217 /*
218 * Signal that page flip was handled, pending event will be sent
219 * on frame done event from the backend.
220 */
221 return true;
222 }
223
224 return false;
225}
226
227static int display_check(struct drm_simple_display_pipe *pipe,
228 struct drm_plane_state *plane_state,
229 struct drm_crtc_state *crtc_state)
230{
231 /*
232 * Xen doesn't initialize vblanking via drm_vblank_init(), so
233 * DRM helpers assume that it doesn't handle vblanking and start
234 * sending out fake VBLANK events automatically.
235 *
236 * As xen contains it's own logic for sending out VBLANK events
237 * in send_pending_event(), disable no_vblank (i.e., the xen
238 * driver has vblanking support).
239 */
240 crtc_state->no_vblank = false;
241
242 return 0;
243}
244
245static void display_update(struct drm_simple_display_pipe *pipe,
246 struct drm_plane_state *old_plane_state)
247{
248 struct xen_drm_front_drm_pipeline *pipeline =
249 to_xen_drm_pipeline(pipe);
250 struct drm_crtc *crtc = &pipe->crtc;
251 struct drm_pending_vblank_event *event;
252 int idx;
253
254 event = crtc->state->event;
255 if (event) {
256 struct drm_device *dev = crtc->dev;
257 unsigned long flags;
258
259 WARN_ON(pipeline->pending_event);
260
261 spin_lock_irqsave(&dev->event_lock, flags);
262 crtc->state->event = NULL;
263
264 pipeline->pending_event = event;
265 spin_unlock_irqrestore(lock: &dev->event_lock, flags);
266 }
267
268 if (!drm_dev_enter(dev: pipe->crtc.dev, idx: &idx)) {
269 send_pending_event(pipeline);
270 return;
271 }
272
273 /*
274 * Send page flip request to the backend *after* we have event cached
275 * above, so on page flip done event from the backend we can
276 * deliver it and there is no race condition between this code and
277 * event from the backend.
278 * If this is not a page flip, e.g. no flip done event from the backend
279 * is expected, then send now.
280 */
281 if (!display_send_page_flip(pipe, old_plane_state))
282 send_pending_event(pipeline);
283
284 drm_dev_exit(idx);
285}
286
287static enum drm_mode_status
288display_mode_valid(struct drm_simple_display_pipe *pipe,
289 const struct drm_display_mode *mode)
290{
291 struct xen_drm_front_drm_pipeline *pipeline =
292 container_of(pipe, struct xen_drm_front_drm_pipeline,
293 pipe);
294
295 if (mode->hdisplay != pipeline->width)
296 return MODE_ERROR;
297
298 if (mode->vdisplay != pipeline->height)
299 return MODE_ERROR;
300
301 return MODE_OK;
302}
303
304static const struct drm_simple_display_pipe_funcs display_funcs = {
305 .mode_valid = display_mode_valid,
306 .enable = display_enable,
307 .disable = display_disable,
308 .check = display_check,
309 .update = display_update,
310};
311
312static int display_pipe_init(struct xen_drm_front_drm_info *drm_info,
313 int index, struct xen_drm_front_cfg_connector *cfg,
314 struct xen_drm_front_drm_pipeline *pipeline)
315{
316 struct drm_device *dev = drm_info->drm_dev;
317 const u32 *formats;
318 int format_count;
319 int ret;
320
321 pipeline->drm_info = drm_info;
322 pipeline->index = index;
323 pipeline->height = cfg->height;
324 pipeline->width = cfg->width;
325
326 INIT_DELAYED_WORK(&pipeline->pflip_to_worker, pflip_to_worker);
327
328 ret = xen_drm_front_conn_init(drm_info, connector: &pipeline->conn);
329 if (ret)
330 return ret;
331
332 formats = xen_drm_front_conn_get_formats(format_count: &format_count);
333
334 return drm_simple_display_pipe_init(dev, pipe: &pipeline->pipe,
335 funcs: &display_funcs, formats,
336 format_count, NULL,
337 connector: &pipeline->conn);
338}
339
340int xen_drm_front_kms_init(struct xen_drm_front_drm_info *drm_info)
341{
342 struct drm_device *dev = drm_info->drm_dev;
343 int i, ret;
344
345 drm_mode_config_init(dev);
346
347 dev->mode_config.min_width = 0;
348 dev->mode_config.min_height = 0;
349 dev->mode_config.max_width = 4095;
350 dev->mode_config.max_height = 2047;
351 dev->mode_config.funcs = &mode_config_funcs;
352
353 for (i = 0; i < drm_info->front_info->cfg.num_connectors; i++) {
354 struct xen_drm_front_cfg_connector *cfg =
355 &drm_info->front_info->cfg.connectors[i];
356 struct xen_drm_front_drm_pipeline *pipeline =
357 &drm_info->pipeline[i];
358
359 ret = display_pipe_init(drm_info, index: i, cfg, pipeline);
360 if (ret) {
361 drm_mode_config_cleanup(dev);
362 return ret;
363 }
364 }
365
366 drm_mode_config_reset(dev);
367 drm_kms_helper_poll_init(dev);
368 return 0;
369}
370
371void xen_drm_front_kms_fini(struct xen_drm_front_drm_info *drm_info)
372{
373 int i;
374
375 for (i = 0; i < drm_info->front_info->cfg.num_connectors; i++) {
376 struct xen_drm_front_drm_pipeline *pipeline =
377 &drm_info->pipeline[i];
378
379 cancel_delayed_work_sync(dwork: &pipeline->pflip_to_worker);
380
381 send_pending_event(pipeline);
382 }
383}
384

source code of linux/drivers/gpu/drm/xen/xen_drm_front_kms.c