xref: /openbmc/linux/drivers/gpu/drm/vkms/vkms_crtc.c (revision 2e7c04aec86758e0adfcad4a24c86593b45807a3)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * This program is free software; you can redistribute it and/or modify
4  * it under the terms of the GNU General Public License as published by
5  * the Free Software Foundation; either version 2 of the License, or
6  * (at your option) any later version.
7  */
8 
9 #include "vkms_drv.h"
10 #include <drm/drm_atomic_helper.h>
11 #include <drm/drm_crtc_helper.h>
12 
13 static void _vblank_handle(struct vkms_output *output)
14 {
15 	struct drm_crtc *crtc = &output->crtc;
16 	struct vkms_crtc_state *state = to_vkms_crtc_state(crtc->state);
17 	bool ret;
18 
19 	spin_lock(&output->lock);
20 	ret = drm_crtc_handle_vblank(crtc);
21 	if (!ret)
22 		DRM_ERROR("vkms failure on handling vblank");
23 
24 	if (state && output->crc_enabled) {
25 		state->n_frame = drm_crtc_accurate_vblank_count(crtc);
26 		queue_work(output->crc_workq, &state->crc_work);
27 	}
28 
29 	spin_unlock(&output->lock);
30 }
31 
32 static enum hrtimer_restart vkms_vblank_simulate(struct hrtimer *timer)
33 {
34 	struct vkms_output *output = container_of(timer, struct vkms_output,
35 						  vblank_hrtimer);
36 	int ret_overrun;
37 
38 	_vblank_handle(output);
39 
40 	ret_overrun = hrtimer_forward_now(&output->vblank_hrtimer,
41 					  output->period_ns);
42 
43 	return HRTIMER_RESTART;
44 }
45 
46 static int vkms_enable_vblank(struct drm_crtc *crtc)
47 {
48 	struct drm_device *dev = crtc->dev;
49 	unsigned int pipe = drm_crtc_index(crtc);
50 	struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
51 	struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
52 
53 	drm_calc_timestamping_constants(crtc, &crtc->mode);
54 
55 	hrtimer_init(&out->vblank_hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
56 	out->vblank_hrtimer.function = &vkms_vblank_simulate;
57 	out->period_ns = ktime_set(0, vblank->framedur_ns);
58 	hrtimer_start(&out->vblank_hrtimer, out->period_ns, HRTIMER_MODE_REL);
59 
60 	return 0;
61 }
62 
63 static void vkms_disable_vblank(struct drm_crtc *crtc)
64 {
65 	struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
66 
67 	hrtimer_cancel(&out->vblank_hrtimer);
68 }
69 
70 bool vkms_get_vblank_timestamp(struct drm_device *dev, unsigned int pipe,
71 			       int *max_error, ktime_t *vblank_time,
72 			       bool in_vblank_irq)
73 {
74 	struct vkms_device *vkmsdev = drm_device_to_vkms_device(dev);
75 	struct vkms_output *output = &vkmsdev->output;
76 
77 	*vblank_time = output->vblank_hrtimer.node.expires;
78 
79 	return true;
80 }
81 
82 static void vkms_atomic_crtc_reset(struct drm_crtc *crtc)
83 {
84 	struct vkms_crtc_state *vkms_state = NULL;
85 
86 	if (crtc->state) {
87 		vkms_state = to_vkms_crtc_state(crtc->state);
88 		__drm_atomic_helper_crtc_destroy_state(crtc->state);
89 		kfree(vkms_state);
90 		crtc->state = NULL;
91 	}
92 
93 	vkms_state = kzalloc(sizeof(*vkms_state), GFP_KERNEL);
94 	if (!vkms_state)
95 		return;
96 
97 	crtc->state = &vkms_state->base;
98 	crtc->state->crtc = crtc;
99 }
100 
101 static struct drm_crtc_state *
102 vkms_atomic_crtc_duplicate_state(struct drm_crtc *crtc)
103 {
104 	struct vkms_crtc_state *vkms_state;
105 
106 	if (WARN_ON(!crtc->state))
107 		return NULL;
108 
109 	vkms_state = kzalloc(sizeof(*vkms_state), GFP_KERNEL);
110 	if (!vkms_state)
111 		return NULL;
112 
113 	__drm_atomic_helper_crtc_duplicate_state(crtc, &vkms_state->base);
114 
115 	INIT_WORK(&vkms_state->crc_work, vkms_crc_work_handle);
116 
117 	return &vkms_state->base;
118 }
119 
120 static void vkms_atomic_crtc_destroy_state(struct drm_crtc *crtc,
121 					   struct drm_crtc_state *state)
122 {
123 	struct vkms_crtc_state *vkms_state = to_vkms_crtc_state(state);
124 
125 	__drm_atomic_helper_crtc_destroy_state(state);
126 
127 	if (vkms_state) {
128 		flush_work(&vkms_state->crc_work);
129 		kfree(vkms_state);
130 	}
131 }
132 
133 static const struct drm_crtc_funcs vkms_crtc_funcs = {
134 	.set_config             = drm_atomic_helper_set_config,
135 	.destroy                = drm_crtc_cleanup,
136 	.page_flip              = drm_atomic_helper_page_flip,
137 	.reset                  = vkms_atomic_crtc_reset,
138 	.atomic_duplicate_state = vkms_atomic_crtc_duplicate_state,
139 	.atomic_destroy_state   = vkms_atomic_crtc_destroy_state,
140 	.enable_vblank		= vkms_enable_vblank,
141 	.disable_vblank		= vkms_disable_vblank,
142 	.set_crc_source		= vkms_set_crc_source,
143 	.verify_crc_source	= vkms_verify_crc_source,
144 };
145 
146 static void vkms_crtc_atomic_enable(struct drm_crtc *crtc,
147 				    struct drm_crtc_state *old_state)
148 {
149 	drm_crtc_vblank_on(crtc);
150 }
151 
152 static void vkms_crtc_atomic_disable(struct drm_crtc *crtc,
153 				     struct drm_crtc_state *old_state)
154 {
155 	drm_crtc_vblank_off(crtc);
156 }
157 
158 static void vkms_crtc_atomic_begin(struct drm_crtc *crtc,
159 				   struct drm_crtc_state *old_crtc_state)
160 {
161 	struct vkms_output *vkms_output = drm_crtc_to_vkms_output(crtc);
162 
163 	/* This lock is held across the atomic commit to block vblank timer
164 	 * from scheduling vkms_crc_work_handle until the crc_data is updated
165 	 */
166 	spin_lock_irq(&vkms_output->lock);
167 }
168 
169 static void vkms_crtc_atomic_flush(struct drm_crtc *crtc,
170 				   struct drm_crtc_state *old_crtc_state)
171 {
172 	struct vkms_output *vkms_output = drm_crtc_to_vkms_output(crtc);
173 	unsigned long flags;
174 
175 	if (crtc->state->event) {
176 		spin_lock_irqsave(&crtc->dev->event_lock, flags);
177 
178 		if (drm_crtc_vblank_get(crtc) != 0)
179 			drm_crtc_send_vblank_event(crtc, crtc->state->event);
180 		else
181 			drm_crtc_arm_vblank_event(crtc, crtc->state->event);
182 
183 		spin_unlock_irqrestore(&crtc->dev->event_lock, flags);
184 
185 		crtc->state->event = NULL;
186 	}
187 
188 	spin_unlock_irq(&vkms_output->lock);
189 }
190 
191 static const struct drm_crtc_helper_funcs vkms_crtc_helper_funcs = {
192 	.atomic_begin	= vkms_crtc_atomic_begin,
193 	.atomic_flush	= vkms_crtc_atomic_flush,
194 	.atomic_enable	= vkms_crtc_atomic_enable,
195 	.atomic_disable	= vkms_crtc_atomic_disable,
196 };
197 
198 int vkms_crtc_init(struct drm_device *dev, struct drm_crtc *crtc,
199 		   struct drm_plane *primary, struct drm_plane *cursor)
200 {
201 	struct vkms_output *vkms_out = drm_crtc_to_vkms_output(crtc);
202 	int ret;
203 
204 	ret = drm_crtc_init_with_planes(dev, crtc, primary, cursor,
205 					&vkms_crtc_funcs, NULL);
206 	if (ret) {
207 		DRM_ERROR("Failed to init CRTC\n");
208 		return ret;
209 	}
210 
211 	drm_crtc_helper_add(crtc, &vkms_crtc_helper_funcs);
212 
213 	spin_lock_init(&vkms_out->lock);
214 
215 	vkms_out->crc_workq = alloc_ordered_workqueue("vkms_crc_workq", 0);
216 
217 	return ret;
218 }
219