1 /*
2 * Copyright (C) 2014 Intel Corporation
3 *
4 * DRM universal plane helper functions
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice (including the next
14 * paragraph) shall be included in all copies or substantial portions of the
15 * Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
23 * SOFTWARE.
24 */
25
26 #include <linux/list.h>
27
28 #include <drm/drm_atomic.h>
29 #include <drm/drm_atomic_helper.h>
30 #include <drm/drm_atomic_uapi.h>
31 #include <drm/drm_device.h>
32 #include <drm/drm_drv.h>
33 #include <drm/drm_encoder.h>
34 #include <drm/drm_plane_helper.h>
35 #include <drm/drm_print.h>
36 #include <drm/drm_rect.h>
37
38 #define SUBPIXEL_MASK 0xffff
39
40 /**
41 * DOC: overview
42 *
43 * This helper library contains helpers to implement primary plane support on
44 * top of the normal CRTC configuration interface.
45 * Since the legacy &drm_mode_config_funcs.set_config interface ties the primary
46 * plane together with the CRTC state this does not allow userspace to disable
47 * the primary plane itself. The default primary plane only expose XRBG8888 and
48 * ARGB8888 as valid pixel formats for the attached framebuffer.
49 *
50 * Drivers are highly recommended to implement proper support for primary
51 * planes, and newly merged drivers must not rely upon these transitional
52 * helpers.
53 *
54 * The plane helpers share the function table structures with other helpers,
55 * specifically also the atomic helpers. See &struct drm_plane_helper_funcs for
56 * the details.
57 */
58
59 /*
60 * Returns the connectors currently associated with a CRTC. This function
61 * should be called twice: once with a NULL connector list to retrieve
62 * the list size, and once with the properly allocated list to be filled in.
63 */
get_connectors_for_crtc(struct drm_crtc * crtc,struct drm_connector ** connector_list,int num_connectors)64 static int get_connectors_for_crtc(struct drm_crtc *crtc,
65 struct drm_connector **connector_list,
66 int num_connectors)
67 {
68 struct drm_device *dev = crtc->dev;
69 struct drm_connector *connector;
70 struct drm_connector_list_iter conn_iter;
71 int count = 0;
72
73 /*
74 * Note: Once we change the plane hooks to more fine-grained locking we
75 * need to grab the connection_mutex here to be able to make these
76 * checks.
77 */
78 WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
79
80 drm_connector_list_iter_begin(dev, &conn_iter);
81 drm_for_each_connector_iter(connector, &conn_iter) {
82 if (connector->encoder && connector->encoder->crtc == crtc) {
83 if (connector_list != NULL && count < num_connectors)
84 *(connector_list++) = connector;
85
86 count++;
87 }
88 }
89 drm_connector_list_iter_end(&conn_iter);
90
91 return count;
92 }
93
drm_plane_helper_check_update(struct drm_plane * plane,struct drm_crtc * crtc,struct drm_framebuffer * fb,struct drm_rect * src,struct drm_rect * dst,unsigned int rotation,int min_scale,int max_scale,bool can_position,bool can_update_disabled,bool * visible)94 static int drm_plane_helper_check_update(struct drm_plane *plane,
95 struct drm_crtc *crtc,
96 struct drm_framebuffer *fb,
97 struct drm_rect *src,
98 struct drm_rect *dst,
99 unsigned int rotation,
100 int min_scale,
101 int max_scale,
102 bool can_position,
103 bool can_update_disabled,
104 bool *visible)
105 {
106 struct drm_plane_state plane_state = {
107 .plane = plane,
108 .crtc = crtc,
109 .fb = fb,
110 .src_x = src->x1,
111 .src_y = src->y1,
112 .src_w = drm_rect_width(src),
113 .src_h = drm_rect_height(src),
114 .crtc_x = dst->x1,
115 .crtc_y = dst->y1,
116 .crtc_w = drm_rect_width(dst),
117 .crtc_h = drm_rect_height(dst),
118 .rotation = rotation,
119 };
120 struct drm_crtc_state crtc_state = {
121 .crtc = crtc,
122 .enable = crtc->enabled,
123 .mode = crtc->mode,
124 };
125 int ret;
126
127 ret = drm_atomic_helper_check_plane_state(&plane_state, &crtc_state,
128 min_scale, max_scale,
129 can_position,
130 can_update_disabled);
131 if (ret)
132 return ret;
133
134 *src = plane_state.src;
135 *dst = plane_state.dst;
136 *visible = plane_state.visible;
137
138 return 0;
139 }
140
141 /**
142 * drm_plane_helper_update_primary - Helper for updating primary planes
143 * @plane: plane to update
144 * @crtc: the plane's new CRTC
145 * @fb: the plane's new framebuffer
146 * @crtc_x: x coordinate within CRTC
147 * @crtc_y: y coordinate within CRTC
148 * @crtc_w: width coordinate within CRTC
149 * @crtc_h: height coordinate within CRTC
150 * @src_x: x coordinate within source
151 * @src_y: y coordinate within source
152 * @src_w: width coordinate within source
153 * @src_h: height coordinate within source
154 * @ctx: modeset locking context
155 *
156 * This helper validates the given parameters and updates the primary plane.
157 *
158 * This function is only useful for non-atomic modesetting. Don't use
159 * it in new drivers.
160 *
161 * Returns:
162 * Zero on success, or an errno code otherwise.
163 */
drm_plane_helper_update_primary(struct drm_plane * plane,struct drm_crtc * crtc,struct drm_framebuffer * fb,int crtc_x,int crtc_y,unsigned int crtc_w,unsigned int crtc_h,uint32_t src_x,uint32_t src_y,uint32_t src_w,uint32_t src_h,struct drm_modeset_acquire_ctx * ctx)164 int drm_plane_helper_update_primary(struct drm_plane *plane, struct drm_crtc *crtc,
165 struct drm_framebuffer *fb,
166 int crtc_x, int crtc_y,
167 unsigned int crtc_w, unsigned int crtc_h,
168 uint32_t src_x, uint32_t src_y,
169 uint32_t src_w, uint32_t src_h,
170 struct drm_modeset_acquire_ctx *ctx)
171 {
172 struct drm_mode_set set = {
173 .crtc = crtc,
174 .fb = fb,
175 .mode = &crtc->mode,
176 .x = src_x >> 16,
177 .y = src_y >> 16,
178 };
179 struct drm_rect src = {
180 .x1 = src_x,
181 .y1 = src_y,
182 .x2 = src_x + src_w,
183 .y2 = src_y + src_h,
184 };
185 struct drm_rect dest = {
186 .x1 = crtc_x,
187 .y1 = crtc_y,
188 .x2 = crtc_x + crtc_w,
189 .y2 = crtc_y + crtc_h,
190 };
191 struct drm_device *dev = plane->dev;
192 struct drm_connector **connector_list;
193 int num_connectors, ret;
194 bool visible;
195
196 if (drm_WARN_ON_ONCE(dev, drm_drv_uses_atomic_modeset(dev)))
197 return -EINVAL;
198
199 ret = drm_plane_helper_check_update(plane, crtc, fb,
200 &src, &dest,
201 DRM_MODE_ROTATE_0,
202 DRM_PLANE_NO_SCALING,
203 DRM_PLANE_NO_SCALING,
204 false, false, &visible);
205 if (ret)
206 return ret;
207
208 if (!visible)
209 /*
210 * Primary plane isn't visible. Note that unless a driver
211 * provides their own disable function, this will just
212 * wind up returning -EINVAL to userspace.
213 */
214 return plane->funcs->disable_plane(plane, ctx);
215
216 /* Find current connectors for CRTC */
217 num_connectors = get_connectors_for_crtc(crtc, NULL, 0);
218 BUG_ON(num_connectors == 0);
219 connector_list = kcalloc(num_connectors, sizeof(*connector_list),
220 GFP_KERNEL);
221 if (!connector_list)
222 return -ENOMEM;
223 get_connectors_for_crtc(crtc, connector_list, num_connectors);
224
225 set.connectors = connector_list;
226 set.num_connectors = num_connectors;
227
228 /*
229 * We call set_config() directly here rather than using
230 * drm_mode_set_config_internal. We're reprogramming the same
231 * connectors that were already in use, so we shouldn't need the extra
232 * cross-CRTC fb refcounting to accommodate stealing connectors.
233 * drm_mode_setplane() already handles the basic refcounting for the
234 * framebuffers involved in this operation.
235 */
236 ret = crtc->funcs->set_config(&set, ctx);
237
238 kfree(connector_list);
239 return ret;
240 }
241 EXPORT_SYMBOL(drm_plane_helper_update_primary);
242
243 /**
244 * drm_plane_helper_disable_primary - Helper for disabling primary planes
245 * @plane: plane to disable
246 * @ctx: modeset locking context
247 *
248 * This helper returns an error when trying to disable the primary
249 * plane.
250 *
251 * This function is only useful for non-atomic modesetting. Don't use
252 * it in new drivers.
253 *
254 * Returns:
255 * An errno code.
256 */
drm_plane_helper_disable_primary(struct drm_plane * plane,struct drm_modeset_acquire_ctx * ctx)257 int drm_plane_helper_disable_primary(struct drm_plane *plane,
258 struct drm_modeset_acquire_ctx *ctx)
259 {
260 struct drm_device *dev = plane->dev;
261
262 drm_WARN_ON_ONCE(dev, drm_drv_uses_atomic_modeset(dev));
263
264 return -EINVAL;
265 }
266 EXPORT_SYMBOL(drm_plane_helper_disable_primary);
267
268 /**
269 * drm_plane_helper_destroy() - Helper for primary plane destruction
270 * @plane: plane to destroy
271 *
272 * Provides a default plane destroy handler for primary planes. This handler
273 * is called during CRTC destruction. We disable the primary plane, remove
274 * it from the DRM plane list, and deallocate the plane structure.
275 */
drm_plane_helper_destroy(struct drm_plane * plane)276 void drm_plane_helper_destroy(struct drm_plane *plane)
277 {
278 drm_plane_cleanup(plane);
279 kfree(plane);
280 }
281 EXPORT_SYMBOL(drm_plane_helper_destroy);
282