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 
35 	if (!conn_state->writeback_job || !conn_state->writeback_job->fb)
36 		return 0;
37 
38 	fb = conn_state->writeback_job->fb;
39 	if (fb->width != mode->hdisplay || fb->height != mode->vdisplay) {
40 		DRM_DEBUG_KMS("Invalid framebuffer size %ux%u\n",
41 			      fb->width, fb->height);
42 		return -EINVAL;
43 	}
44 
45 	if (fb->format->format != vkms_wb_formats[0]) {
46 		DRM_DEBUG_KMS("Invalid pixel format %p4cc\n",
47 			      &fb->format->format);
48 		return -EINVAL;
49 	}
50 
51 	return 0;
52 }
53 
54 static const struct drm_encoder_helper_funcs vkms_wb_encoder_helper_funcs = {
55 	.atomic_check = vkms_wb_encoder_atomic_check,
56 };
57 
58 static int vkms_wb_connector_get_modes(struct drm_connector *connector)
59 {
60 	struct drm_device *dev = connector->dev;
61 
62 	return drm_add_modes_noedid(connector, dev->mode_config.max_width,
63 				    dev->mode_config.max_height);
64 }
65 
66 static int vkms_wb_prepare_job(struct drm_writeback_connector *wb_connector,
67 			       struct drm_writeback_job *job)
68 {
69 	struct vkms_writeback_job *vkmsjob;
70 	int ret;
71 
72 	if (!job->fb)
73 		return 0;
74 
75 	vkmsjob = kzalloc(sizeof(*vkmsjob), GFP_KERNEL);
76 	if (!vkmsjob)
77 		return -ENOMEM;
78 
79 	ret = drm_gem_fb_vmap(job->fb, vkmsjob->map, vkmsjob->data);
80 	if (ret) {
81 		DRM_ERROR("vmap failed: %d\n", ret);
82 		goto err_kfree;
83 	}
84 
85 	job->priv = vkmsjob;
86 
87 	return 0;
88 
89 err_kfree:
90 	kfree(vkmsjob);
91 	return ret;
92 }
93 
94 static void vkms_wb_cleanup_job(struct drm_writeback_connector *connector,
95 				struct drm_writeback_job *job)
96 {
97 	struct vkms_writeback_job *vkmsjob = job->priv;
98 	struct vkms_device *vkmsdev;
99 
100 	if (!job->fb)
101 		return;
102 
103 	drm_gem_fb_vunmap(job->fb, vkmsjob->map);
104 
105 	vkmsdev = drm_device_to_vkms_device(job->fb->dev);
106 	vkms_set_composer(&vkmsdev->output, false);
107 	kfree(vkmsjob);
108 }
109 
110 static void vkms_wb_atomic_commit(struct drm_connector *conn,
111 				  struct drm_atomic_state *state)
112 {
113 	struct drm_connector_state *connector_state = drm_atomic_get_new_connector_state(state,
114 											 conn);
115 	struct vkms_device *vkmsdev = drm_device_to_vkms_device(conn->dev);
116 	struct vkms_output *output = &vkmsdev->output;
117 	struct drm_writeback_connector *wb_conn = &output->wb_connector;
118 	struct drm_connector_state *conn_state = wb_conn->base.state;
119 	struct vkms_crtc_state *crtc_state = output->composer_state;
120 
121 	if (!conn_state)
122 		return;
123 
124 	vkms_set_composer(&vkmsdev->output, true);
125 
126 	spin_lock_irq(&output->composer_lock);
127 	crtc_state->active_writeback = conn_state->writeback_job->priv;
128 	crtc_state->wb_pending = true;
129 	spin_unlock_irq(&output->composer_lock);
130 	drm_writeback_queue_job(wb_conn, connector_state);
131 }
132 
133 static const struct drm_connector_helper_funcs vkms_wb_conn_helper_funcs = {
134 	.get_modes = vkms_wb_connector_get_modes,
135 	.prepare_writeback_job = vkms_wb_prepare_job,
136 	.cleanup_writeback_job = vkms_wb_cleanup_job,
137 	.atomic_commit = vkms_wb_atomic_commit,
138 };
139 
140 int vkms_enable_writeback_connector(struct vkms_device *vkmsdev)
141 {
142 	struct drm_writeback_connector *wb = &vkmsdev->output.wb_connector;
143 
144 	drm_connector_helper_add(&wb->base, &vkms_wb_conn_helper_funcs);
145 
146 	return drm_writeback_connector_init(&vkmsdev->drm, wb,
147 					    &vkms_wb_connector_funcs,
148 					    &vkms_wb_encoder_helper_funcs,
149 					    vkms_wb_formats,
150 					    ARRAY_SIZE(vkms_wb_formats),
151 					    1);
152 }
153