drm/msm/hdmi: Enable HPD after HDMI IRQ is set up
[linux/fpc-iii.git] / drivers / gpu / drm / drm_gem_framebuffer_helper.c
blob2810d413141182e4b6298524612670aa34a54757
1 /*
2 * drm gem framebuffer helper functions
4 * Copyright (C) 2017 Noralf Trønnes
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
12 #include <linux/dma-buf.h>
13 #include <linux/dma-fence.h>
14 #include <linux/reservation.h>
15 #include <linux/slab.h>
17 #include <drm/drmP.h>
18 #include <drm/drm_atomic.h>
19 #include <drm/drm_fb_helper.h>
20 #include <drm/drm_fourcc.h>
21 #include <drm/drm_framebuffer.h>
22 #include <drm/drm_gem.h>
23 #include <drm/drm_gem_framebuffer_helper.h>
24 #include <drm/drm_modeset_helper.h>
25 #include <drm/drm_simple_kms_helper.h>
27 /**
28 * DOC: overview
30 * This library provides helpers for drivers that don't subclass
31 * &drm_framebuffer and use &drm_gem_object for their backing storage.
33 * Drivers without additional needs to validate framebuffers can simply use
34 * drm_gem_fb_create() and everything is wired up automatically. Other drivers
35 * can use all parts independently.
38 /**
39 * drm_gem_fb_get_obj() - Get GEM object backing the framebuffer
40 * @fb: Framebuffer
41 * @plane: Plane index
43 * No additional reference is taken beyond the one that the &drm_frambuffer
44 * already holds.
46 * Returns:
47 * Pointer to &drm_gem_object for the given framebuffer and plane index or NULL
48 * if it does not exist.
50 struct drm_gem_object *drm_gem_fb_get_obj(struct drm_framebuffer *fb,
51 unsigned int plane)
53 if (plane >= 4)
54 return NULL;
56 return fb->obj[plane];
58 EXPORT_SYMBOL_GPL(drm_gem_fb_get_obj);
60 static struct drm_framebuffer *
61 drm_gem_fb_alloc(struct drm_device *dev,
62 const struct drm_mode_fb_cmd2 *mode_cmd,
63 struct drm_gem_object **obj, unsigned int num_planes,
64 const struct drm_framebuffer_funcs *funcs)
66 struct drm_framebuffer *fb;
67 int ret, i;
69 fb = kzalloc(sizeof(*fb), GFP_KERNEL);
70 if (!fb)
71 return ERR_PTR(-ENOMEM);
73 drm_helper_mode_fill_fb_struct(dev, fb, mode_cmd);
75 for (i = 0; i < num_planes; i++)
76 fb->obj[i] = obj[i];
78 ret = drm_framebuffer_init(dev, fb, funcs);
79 if (ret) {
80 DRM_DEV_ERROR(dev->dev, "Failed to init framebuffer: %d\n",
81 ret);
82 kfree(fb);
83 return ERR_PTR(ret);
86 return fb;
89 /**
90 * drm_gem_fb_destroy - Free GEM backed framebuffer
91 * @fb: Framebuffer
93 * Frees a GEM backed framebuffer with its backing buffer(s) and the structure
94 * itself. Drivers can use this as their &drm_framebuffer_funcs->destroy
95 * callback.
97 void drm_gem_fb_destroy(struct drm_framebuffer *fb)
99 int i;
101 for (i = 0; i < 4; i++)
102 drm_gem_object_put_unlocked(fb->obj[i]);
104 drm_framebuffer_cleanup(fb);
105 kfree(fb);
107 EXPORT_SYMBOL(drm_gem_fb_destroy);
110 * drm_gem_fb_create_handle - Create handle for GEM backed framebuffer
111 * @fb: Framebuffer
112 * @file: DRM file to register the handle for
113 * @handle: Pointer to return the created handle
115 * This function creates a handle for the GEM object backing the framebuffer.
116 * Drivers can use this as their &drm_framebuffer_funcs->create_handle
117 * callback. The GETFB IOCTL calls into this callback.
119 * Returns:
120 * 0 on success or a negative error code on failure.
122 int drm_gem_fb_create_handle(struct drm_framebuffer *fb, struct drm_file *file,
123 unsigned int *handle)
125 return drm_gem_handle_create(file, fb->obj[0], handle);
127 EXPORT_SYMBOL(drm_gem_fb_create_handle);
130 * drm_gem_fb_create_with_funcs() - Helper function for the
131 * &drm_mode_config_funcs.fb_create
132 * callback
133 * @dev: DRM device
134 * @file: DRM file that holds the GEM handle(s) backing the framebuffer
135 * @mode_cmd: Metadata from the userspace framebuffer creation request
136 * @funcs: vtable to be used for the new framebuffer object
138 * This can be used to set &drm_framebuffer_funcs for drivers that need the
139 * &drm_framebuffer_funcs.dirty callback. Use drm_gem_fb_create() if you don't
140 * need to change &drm_framebuffer_funcs.
141 * The function does buffer size validation.
143 * Returns:
144 * Pointer to a &drm_framebuffer on success or an error pointer on failure.
146 struct drm_framebuffer *
147 drm_gem_fb_create_with_funcs(struct drm_device *dev, struct drm_file *file,
148 const struct drm_mode_fb_cmd2 *mode_cmd,
149 const struct drm_framebuffer_funcs *funcs)
151 const struct drm_format_info *info;
152 struct drm_gem_object *objs[4];
153 struct drm_framebuffer *fb;
154 int ret, i;
156 info = drm_get_format_info(dev, mode_cmd);
157 if (!info)
158 return ERR_PTR(-EINVAL);
160 for (i = 0; i < info->num_planes; i++) {
161 unsigned int width = mode_cmd->width / (i ? info->hsub : 1);
162 unsigned int height = mode_cmd->height / (i ? info->vsub : 1);
163 unsigned int min_size;
165 objs[i] = drm_gem_object_lookup(file, mode_cmd->handles[i]);
166 if (!objs[i]) {
167 DRM_DEBUG_KMS("Failed to lookup GEM object\n");
168 ret = -ENOENT;
169 goto err_gem_object_put;
172 min_size = (height - 1) * mode_cmd->pitches[i]
173 + width * info->cpp[i]
174 + mode_cmd->offsets[i];
176 if (objs[i]->size < min_size) {
177 drm_gem_object_put_unlocked(objs[i]);
178 ret = -EINVAL;
179 goto err_gem_object_put;
183 fb = drm_gem_fb_alloc(dev, mode_cmd, objs, i, funcs);
184 if (IS_ERR(fb)) {
185 ret = PTR_ERR(fb);
186 goto err_gem_object_put;
189 return fb;
191 err_gem_object_put:
192 for (i--; i >= 0; i--)
193 drm_gem_object_put_unlocked(objs[i]);
195 return ERR_PTR(ret);
197 EXPORT_SYMBOL_GPL(drm_gem_fb_create_with_funcs);
199 static const struct drm_framebuffer_funcs drm_gem_fb_funcs = {
200 .destroy = drm_gem_fb_destroy,
201 .create_handle = drm_gem_fb_create_handle,
205 * drm_gem_fb_create() - Helper function for the
206 * &drm_mode_config_funcs.fb_create callback
207 * @dev: DRM device
208 * @file: DRM file that holds the GEM handle(s) backing the framebuffer
209 * @mode_cmd: Metadata from the userspace framebuffer creation request
211 * This function creates a new framebuffer object described by
212 * &drm_mode_fb_cmd2. This description includes handles for the buffer(s)
213 * backing the framebuffer.
215 * If your hardware has special alignment or pitch requirements these should be
216 * checked before calling this function. The function does buffer size
217 * validation. Use drm_gem_fb_create_with_funcs() if you need to set
218 * &drm_framebuffer_funcs.dirty.
220 * Drivers can use this as their &drm_mode_config_funcs.fb_create callback.
221 * The ADDFB2 IOCTL calls into this callback.
223 * Returns:
224 * Pointer to a &drm_framebuffer on success or an error pointer on failure.
226 struct drm_framebuffer *
227 drm_gem_fb_create(struct drm_device *dev, struct drm_file *file,
228 const struct drm_mode_fb_cmd2 *mode_cmd)
230 return drm_gem_fb_create_with_funcs(dev, file, mode_cmd,
231 &drm_gem_fb_funcs);
233 EXPORT_SYMBOL_GPL(drm_gem_fb_create);
236 * drm_gem_fb_prepare_fb() - Prepare a GEM backed framebuffer
237 * @plane: Plane
238 * @state: Plane state the fence will be attached to
240 * This function prepares a GEM backed framebuffer for scanout by checking if
241 * the plane framebuffer has a DMA-BUF attached. If it does, it extracts the
242 * exclusive fence and attaches it to the plane state for the atomic helper to
243 * wait on. This function can be used as the &drm_plane_helper_funcs.prepare_fb
244 * callback.
246 * There is no need for &drm_plane_helper_funcs.cleanup_fb hook for simple
247 * gem based framebuffer drivers which have their buffers always pinned in
248 * memory.
250 int drm_gem_fb_prepare_fb(struct drm_plane *plane,
251 struct drm_plane_state *state)
253 struct dma_buf *dma_buf;
254 struct dma_fence *fence;
256 if (!state->fb)
257 return 0;
259 dma_buf = drm_gem_fb_get_obj(state->fb, 0)->dma_buf;
260 if (dma_buf) {
261 fence = reservation_object_get_excl_rcu(dma_buf->resv);
262 drm_atomic_set_fence_for_plane(state, fence);
265 return 0;
267 EXPORT_SYMBOL_GPL(drm_gem_fb_prepare_fb);
270 * drm_gem_fb_simple_display_pipe_prepare_fb - prepare_fb helper for
271 * &drm_simple_display_pipe
272 * @pipe: Simple display pipe
273 * @plane_state: Plane state
275 * This function uses drm_gem_fb_prepare_fb() to check if the plane FB has a
276 * &dma_buf attached, extracts the exclusive fence and attaches it to plane
277 * state for the atomic helper to wait on. Drivers can use this as their
278 * &drm_simple_display_pipe_funcs.prepare_fb callback.
280 int drm_gem_fb_simple_display_pipe_prepare_fb(struct drm_simple_display_pipe *pipe,
281 struct drm_plane_state *plane_state)
283 return drm_gem_fb_prepare_fb(&pipe->plane, plane_state);
285 EXPORT_SYMBOL(drm_gem_fb_simple_display_pipe_prepare_fb);
288 * drm_gem_fbdev_fb_create - Create a GEM backed &drm_framebuffer for fbdev
289 * emulation
290 * @dev: DRM device
291 * @sizes: fbdev size description
292 * @pitch_align: Optional pitch alignment
293 * @obj: GEM object backing the framebuffer
294 * @funcs: Optional vtable to be used for the new framebuffer object when the
295 * dirty callback is needed.
297 * This function creates a framebuffer from a &drm_fb_helper_surface_size
298 * description for use in the &drm_fb_helper_funcs.fb_probe callback.
300 * Returns:
301 * Pointer to a &drm_framebuffer on success or an error pointer on failure.
303 struct drm_framebuffer *
304 drm_gem_fbdev_fb_create(struct drm_device *dev,
305 struct drm_fb_helper_surface_size *sizes,
306 unsigned int pitch_align, struct drm_gem_object *obj,
307 const struct drm_framebuffer_funcs *funcs)
309 struct drm_mode_fb_cmd2 mode_cmd = { 0 };
311 mode_cmd.width = sizes->surface_width;
312 mode_cmd.height = sizes->surface_height;
313 mode_cmd.pitches[0] = sizes->surface_width *
314 DIV_ROUND_UP(sizes->surface_bpp, 8);
315 if (pitch_align)
316 mode_cmd.pitches[0] = roundup(mode_cmd.pitches[0],
317 pitch_align);
318 mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
319 sizes->surface_depth);
320 if (obj->size < mode_cmd.pitches[0] * mode_cmd.height)
321 return ERR_PTR(-EINVAL);
323 if (!funcs)
324 funcs = &drm_gem_fb_funcs;
326 return drm_gem_fb_alloc(dev, &mode_cmd, &obj, 1, funcs);
328 EXPORT_SYMBOL(drm_gem_fbdev_fb_create);