xref: /openbmc/linux/drivers/gpu/drm/vkms/vkms_plane.c (revision 0b26ca68)
1 // SPDX-License-Identifier: GPL-2.0+
2 
3 #include <linux/dma-buf-map.h>
4 
5 #include <drm/drm_atomic.h>
6 #include <drm/drm_atomic_helper.h>
7 #include <drm/drm_fourcc.h>
8 #include <drm/drm_gem_framebuffer_helper.h>
9 #include <drm/drm_plane_helper.h>
10 #include <drm/drm_gem_shmem_helper.h>
11 
12 #include "vkms_drv.h"
13 
14 static const u32 vkms_formats[] = {
15 	DRM_FORMAT_XRGB8888,
16 };
17 
18 static const u32 vkms_cursor_formats[] = {
19 	DRM_FORMAT_ARGB8888,
20 };
21 
22 static struct drm_plane_state *
23 vkms_plane_duplicate_state(struct drm_plane *plane)
24 {
25 	struct vkms_plane_state *vkms_state;
26 	struct vkms_composer *composer;
27 
28 	vkms_state = kzalloc(sizeof(*vkms_state), GFP_KERNEL);
29 	if (!vkms_state)
30 		return NULL;
31 
32 	composer = kzalloc(sizeof(*composer), GFP_KERNEL);
33 	if (!composer) {
34 		DRM_DEBUG_KMS("Couldn't allocate composer\n");
35 		kfree(vkms_state);
36 		return NULL;
37 	}
38 
39 	vkms_state->composer = composer;
40 
41 	__drm_atomic_helper_plane_duplicate_state(plane,
42 						  &vkms_state->base);
43 
44 	return &vkms_state->base;
45 }
46 
47 static void vkms_plane_destroy_state(struct drm_plane *plane,
48 				     struct drm_plane_state *old_state)
49 {
50 	struct vkms_plane_state *vkms_state = to_vkms_plane_state(old_state);
51 	struct drm_crtc *crtc = vkms_state->base.crtc;
52 
53 	if (crtc) {
54 		/* dropping the reference we acquired in
55 		 * vkms_primary_plane_update()
56 		 */
57 		if (drm_framebuffer_read_refcount(&vkms_state->composer->fb))
58 			drm_framebuffer_put(&vkms_state->composer->fb);
59 	}
60 
61 	kfree(vkms_state->composer);
62 	vkms_state->composer = NULL;
63 
64 	__drm_atomic_helper_plane_destroy_state(old_state);
65 	kfree(vkms_state);
66 }
67 
68 static void vkms_plane_reset(struct drm_plane *plane)
69 {
70 	struct vkms_plane_state *vkms_state;
71 
72 	if (plane->state)
73 		vkms_plane_destroy_state(plane, plane->state);
74 
75 	vkms_state = kzalloc(sizeof(*vkms_state), GFP_KERNEL);
76 	if (!vkms_state) {
77 		DRM_ERROR("Cannot allocate vkms_plane_state\n");
78 		return;
79 	}
80 
81 	plane->state = &vkms_state->base;
82 	plane->state->plane = plane;
83 }
84 
85 static const struct drm_plane_funcs vkms_plane_funcs = {
86 	.update_plane		= drm_atomic_helper_update_plane,
87 	.disable_plane		= drm_atomic_helper_disable_plane,
88 	.destroy		= drm_plane_cleanup,
89 	.reset			= vkms_plane_reset,
90 	.atomic_duplicate_state = vkms_plane_duplicate_state,
91 	.atomic_destroy_state	= vkms_plane_destroy_state,
92 };
93 
94 static void vkms_plane_atomic_update(struct drm_plane *plane,
95 				     struct drm_plane_state *old_state)
96 {
97 	struct vkms_plane_state *vkms_plane_state;
98 	struct drm_framebuffer *fb = plane->state->fb;
99 	struct vkms_composer *composer;
100 
101 	if (!plane->state->crtc || !fb)
102 		return;
103 
104 	vkms_plane_state = to_vkms_plane_state(plane->state);
105 
106 	composer = vkms_plane_state->composer;
107 	memcpy(&composer->src, &plane->state->src, sizeof(struct drm_rect));
108 	memcpy(&composer->dst, &plane->state->dst, sizeof(struct drm_rect));
109 	memcpy(&composer->fb, fb, sizeof(struct drm_framebuffer));
110 	drm_framebuffer_get(&composer->fb);
111 	composer->offset = fb->offsets[0];
112 	composer->pitch = fb->pitches[0];
113 	composer->cpp = fb->format->cpp[0];
114 }
115 
116 static int vkms_plane_atomic_check(struct drm_plane *plane,
117 				   struct drm_plane_state *state)
118 {
119 	struct drm_crtc_state *crtc_state;
120 	bool can_position = false;
121 	int ret;
122 
123 	if (!state->fb || WARN_ON(!state->crtc))
124 		return 0;
125 
126 	crtc_state = drm_atomic_get_crtc_state(state->state, state->crtc);
127 	if (IS_ERR(crtc_state))
128 		return PTR_ERR(crtc_state);
129 
130 	if (plane->type == DRM_PLANE_TYPE_CURSOR)
131 		can_position = true;
132 
133 	ret = drm_atomic_helper_check_plane_state(state, crtc_state,
134 						  DRM_PLANE_HELPER_NO_SCALING,
135 						  DRM_PLANE_HELPER_NO_SCALING,
136 						  can_position, true);
137 	if (ret != 0)
138 		return ret;
139 
140 	/* for now primary plane must be visible and full screen */
141 	if (!state->visible && !can_position)
142 		return -EINVAL;
143 
144 	return 0;
145 }
146 
147 static int vkms_prepare_fb(struct drm_plane *plane,
148 			   struct drm_plane_state *state)
149 {
150 	struct drm_gem_object *gem_obj;
151 	struct dma_buf_map map;
152 	int ret;
153 
154 	if (!state->fb)
155 		return 0;
156 
157 	gem_obj = drm_gem_fb_get_obj(state->fb, 0);
158 	ret = drm_gem_shmem_vmap(gem_obj, &map);
159 	if (ret)
160 		DRM_ERROR("vmap failed: %d\n", ret);
161 
162 	return drm_gem_fb_prepare_fb(plane, state);
163 }
164 
165 static void vkms_cleanup_fb(struct drm_plane *plane,
166 			    struct drm_plane_state *old_state)
167 {
168 	struct drm_gem_object *gem_obj;
169 	struct drm_gem_shmem_object *shmem_obj;
170 	struct dma_buf_map map;
171 
172 	if (!old_state->fb)
173 		return;
174 
175 	gem_obj = drm_gem_fb_get_obj(old_state->fb, 0);
176 	shmem_obj = to_drm_gem_shmem_obj(drm_gem_fb_get_obj(old_state->fb, 0));
177 	dma_buf_map_set_vaddr(&map, shmem_obj->vaddr);
178 	drm_gem_shmem_vunmap(gem_obj, &map);
179 }
180 
181 static const struct drm_plane_helper_funcs vkms_primary_helper_funcs = {
182 	.atomic_update		= vkms_plane_atomic_update,
183 	.atomic_check		= vkms_plane_atomic_check,
184 	.prepare_fb		= vkms_prepare_fb,
185 	.cleanup_fb		= vkms_cleanup_fb,
186 };
187 
188 struct drm_plane *vkms_plane_init(struct vkms_device *vkmsdev,
189 				  enum drm_plane_type type, int index)
190 {
191 	struct drm_device *dev = &vkmsdev->drm;
192 	const struct drm_plane_helper_funcs *funcs;
193 	struct drm_plane *plane;
194 	const u32 *formats;
195 	int ret, nformats;
196 
197 	plane = kzalloc(sizeof(*plane), GFP_KERNEL);
198 	if (!plane)
199 		return ERR_PTR(-ENOMEM);
200 
201 	if (type == DRM_PLANE_TYPE_CURSOR) {
202 		formats = vkms_cursor_formats;
203 		nformats = ARRAY_SIZE(vkms_cursor_formats);
204 		funcs = &vkms_primary_helper_funcs;
205 	} else {
206 		formats = vkms_formats;
207 		nformats = ARRAY_SIZE(vkms_formats);
208 		funcs = &vkms_primary_helper_funcs;
209 	}
210 
211 	ret = drm_universal_plane_init(dev, plane, 1 << index,
212 				       &vkms_plane_funcs,
213 				       formats, nformats,
214 				       NULL, type, NULL);
215 	if (ret) {
216 		kfree(plane);
217 		return ERR_PTR(ret);
218 	}
219 
220 	drm_plane_helper_add(plane, funcs);
221 
222 	return plane;
223 }
224