1 // SPDX-License-Identifier: GPL-2.0+
2 
3 #include <linux/iosys-map.h>
4 
5 #include <drm/drm_atomic.h>
6 #include <drm/drm_edid.h>
7 #include <drm/drm_fourcc.h>
8 #include <drm/drm_writeback.h>
9 #include <drm/drm_probe_helper.h>
10 #include <drm/drm_atomic_helper.h>
11 #include <drm/drm_gem_framebuffer_helper.h>
12 #include <drm/drm_gem_shmem_helper.h>
13 
14 #include "vkms_drv.h"
15 
16 static const u32 vkms_wb_formats[] = {
17 	DRM_FORMAT_XRGB8888,
18 };
19 
20 static const struct drm_connector_funcs vkms_wb_connector_funcs = {
21 	.fill_modes = drm_helper_probe_single_connector_modes,
22 	.destroy = drm_connector_cleanup,
23 	.reset = drm_atomic_helper_connector_reset,
24 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
25 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
26 };
27 
28 static int vkms_wb_encoder_atomic_check(struct drm_encoder *encoder,
29 					struct drm_crtc_state *crtc_state,
30 					struct drm_connector_state *conn_state)
31 {
32 	struct drm_framebuffer *fb;
33 	const struct drm_display_mode *mode = &crtc_state->mode;
34 	int ret;
35 
36 	if (!conn_state->writeback_job || !conn_state->writeback_job->fb)
37 		return 0;
38 
39 	fb = conn_state->writeback_job->fb;
40 	if (fb->width != mode->hdisplay || fb->height != mode->vdisplay) {
41 		DRM_DEBUG_KMS("Invalid framebuffer size %ux%u\n",
42 			      fb->width, fb->height);
43 		return -EINVAL;
44 	}
45 
46 	ret = drm_atomic_helper_check_wb_encoder_state(encoder, conn_state);
47 	if (ret < 0)
48 		return ret;
49 
50 	return 0;
51 }
52 
53 static const struct drm_encoder_helper_funcs vkms_wb_encoder_helper_funcs = {
54 	.atomic_check = vkms_wb_encoder_atomic_check,
55 };
56 
57 static int vkms_wb_connector_get_modes(struct drm_connector *connector)
58 {
59 	struct drm_device *dev = connector->dev;
60 
61 	return drm_add_modes_noedid(connector, dev->mode_config.max_width,
62 				    dev->mode_config.max_height);
63 }
64 
65 static int vkms_wb_prepare_job(struct drm_writeback_connector *wb_connector,
66 			       struct drm_writeback_job *job)
67 {
68 	struct vkms_writeback_job *vkmsjob;
69 	int ret;
70 
71 	if (!job->fb)
72 		return 0;
73 
74 	vkmsjob = kzalloc(sizeof(*vkmsjob), GFP_KERNEL);
75 	if (!vkmsjob)
76 		return -ENOMEM;
77 
78 	ret = drm_gem_fb_vmap(job->fb, vkmsjob->wb_frame_info.map, vkmsjob->data);
79 	if (ret) {
80 		DRM_ERROR("vmap failed: %d\n", ret);
81 		goto err_kfree;
82 	}
83 
84 	vkmsjob->wb_frame_info.fb = job->fb;
85 	drm_framebuffer_get(vkmsjob->wb_frame_info.fb);
86 
87 	job->priv = vkmsjob;
88 
89 	return 0;
90 
91 err_kfree:
92 	kfree(vkmsjob);
93 	return ret;
94 }
95 
96 static void vkms_wb_cleanup_job(struct drm_writeback_connector *connector,
97 				struct drm_writeback_job *job)
98 {
99 	struct vkms_writeback_job *vkmsjob = job->priv;
100 	struct vkms_device *vkmsdev;
101 
102 	if (!job->fb)
103 		return;
104 
105 	drm_gem_fb_vunmap(job->fb, vkmsjob->wb_frame_info.map);
106 
107 	drm_framebuffer_put(vkmsjob->wb_frame_info.fb);
108 
109 	vkmsdev = drm_device_to_vkms_device(job->fb->dev);
110 	vkms_set_composer(&vkmsdev->output, false);
111 	kfree(vkmsjob);
112 }
113 
114 static void vkms_wb_atomic_commit(struct drm_connector *conn,
115 				  struct drm_atomic_state *state)
116 {
117 	struct drm_connector_state *connector_state = drm_atomic_get_new_connector_state(state,
118 											 conn);
119 	struct vkms_device *vkmsdev = drm_device_to_vkms_device(conn->dev);
120 	struct vkms_output *output = &vkmsdev->output;
121 	struct drm_writeback_connector *wb_conn = &output->wb_connector;
122 	struct drm_connector_state *conn_state = wb_conn->base.state;
123 	struct vkms_crtc_state *crtc_state = output->composer_state;
124 	struct drm_framebuffer *fb = connector_state->writeback_job->fb;
125 	struct vkms_writeback_job *active_wb;
126 	struct vkms_frame_info *wb_frame_info;
127 
128 	if (!conn_state)
129 		return;
130 
131 	vkms_set_composer(&vkmsdev->output, true);
132 
133 	active_wb = conn_state->writeback_job->priv;
134 	wb_frame_info = &active_wb->wb_frame_info;
135 
136 	spin_lock_irq(&output->composer_lock);
137 	crtc_state->active_writeback = active_wb;
138 	wb_frame_info->offset = fb->offsets[0];
139 	wb_frame_info->pitch = fb->pitches[0];
140 	wb_frame_info->cpp = fb->format->cpp[0];
141 	crtc_state->wb_pending = true;
142 	spin_unlock_irq(&output->composer_lock);
143 	drm_writeback_queue_job(wb_conn, connector_state);
144 }
145 
146 static const struct drm_connector_helper_funcs vkms_wb_conn_helper_funcs = {
147 	.get_modes = vkms_wb_connector_get_modes,
148 	.prepare_writeback_job = vkms_wb_prepare_job,
149 	.cleanup_writeback_job = vkms_wb_cleanup_job,
150 	.atomic_commit = vkms_wb_atomic_commit,
151 };
152 
153 int vkms_enable_writeback_connector(struct vkms_device *vkmsdev)
154 {
155 	struct drm_writeback_connector *wb = &vkmsdev->output.wb_connector;
156 
157 	drm_connector_helper_add(&wb->base, &vkms_wb_conn_helper_funcs);
158 
159 	return drm_writeback_connector_init(&vkmsdev->drm, wb,
160 					    &vkms_wb_connector_funcs,
161 					    &vkms_wb_encoder_helper_funcs,
162 					    vkms_wb_formats,
163 					    ARRAY_SIZE(vkms_wb_formats),
164 					    1);
165 }
166