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