xref: /linux/drivers/gpu/drm/sti/sti_drv.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * Copyright (C) STMicroelectronics SA 2014
3  * Author: Benjamin Gaignard <benjamin.gaignard@st.com> for STMicroelectronics.
4  * License terms:  GNU General Public License (GPL), version 2
5  */
6 
7 #include <drm/drmP.h>
8 
9 #include <linux/component.h>
10 #include <linux/debugfs.h>
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/of_platform.h>
14 
15 #include <drm/drm_atomic.h>
16 #include <drm/drm_atomic_helper.h>
17 #include <drm/drm_crtc_helper.h>
18 #include <drm/drm_gem_cma_helper.h>
19 #include <drm/drm_fb_cma_helper.h>
20 
21 #include "sti_crtc.h"
22 #include "sti_drv.h"
23 
24 #define DRIVER_NAME	"sti"
25 #define DRIVER_DESC	"STMicroelectronics SoC DRM"
26 #define DRIVER_DATE	"20140601"
27 #define DRIVER_MAJOR	1
28 #define DRIVER_MINOR	0
29 
30 #define STI_MAX_FB_HEIGHT	4096
31 #define STI_MAX_FB_WIDTH	4096
32 
33 static void sti_atomic_schedule(struct sti_private *private,
34 				struct drm_atomic_state *state)
35 {
36 	private->commit.state = state;
37 	schedule_work(&private->commit.work);
38 }
39 
40 static void sti_atomic_complete(struct sti_private *private,
41 				struct drm_atomic_state *state)
42 {
43 	struct drm_device *drm = private->drm_dev;
44 
45 	/*
46 	 * Everything below can be run asynchronously without the need to grab
47 	 * any modeset locks at all under one condition: It must be guaranteed
48 	 * that the asynchronous work has either been cancelled (if the driver
49 	 * supports it, which at least requires that the framebuffers get
50 	 * cleaned up with drm_atomic_helper_cleanup_planes()) or completed
51 	 * before the new state gets committed on the software side with
52 	 * drm_atomic_helper_swap_state().
53 	 *
54 	 * This scheme allows new atomic state updates to be prepared and
55 	 * checked in parallel to the asynchronous completion of the previous
56 	 * update. Which is important since compositors need to figure out the
57 	 * composition of the next frame right after having submitted the
58 	 * current layout.
59 	 */
60 
61 	drm_atomic_helper_commit_modeset_disables(drm, state);
62 	drm_atomic_helper_commit_planes(drm, state);
63 	drm_atomic_helper_commit_modeset_enables(drm, state);
64 
65 	drm_atomic_helper_wait_for_vblanks(drm, state);
66 
67 	drm_atomic_helper_cleanup_planes(drm, state);
68 	drm_atomic_state_free(state);
69 }
70 
71 static void sti_atomic_work(struct work_struct *work)
72 {
73 	struct sti_private *private = container_of(work,
74 			struct sti_private, commit.work);
75 
76 	sti_atomic_complete(private, private->commit.state);
77 }
78 
79 static int sti_atomic_commit(struct drm_device *drm,
80 			     struct drm_atomic_state *state, bool async)
81 {
82 	struct sti_private *private = drm->dev_private;
83 	int err;
84 
85 	err = drm_atomic_helper_prepare_planes(drm, state);
86 	if (err)
87 		return err;
88 
89 	/* serialize outstanding asynchronous commits */
90 	mutex_lock(&private->commit.lock);
91 	flush_work(&private->commit.work);
92 
93 	/*
94 	 * This is the point of no return - everything below never fails except
95 	 * when the hw goes bonghits. Which means we can commit the new state on
96 	 * the software side now.
97 	 */
98 
99 	drm_atomic_helper_swap_state(drm, state);
100 
101 	if (async)
102 		sti_atomic_schedule(private, state);
103 	else
104 		sti_atomic_complete(private, state);
105 
106 	mutex_unlock(&private->commit.lock);
107 	return 0;
108 }
109 
110 static struct drm_mode_config_funcs sti_mode_config_funcs = {
111 	.fb_create = drm_fb_cma_create,
112 	.atomic_check = drm_atomic_helper_check,
113 	.atomic_commit = sti_atomic_commit,
114 };
115 
116 static void sti_mode_config_init(struct drm_device *dev)
117 {
118 	dev->mode_config.min_width = 0;
119 	dev->mode_config.min_height = 0;
120 
121 	/*
122 	 * set max width and height as default value.
123 	 * this value would be used to check framebuffer size limitation
124 	 * at drm_mode_addfb().
125 	 */
126 	dev->mode_config.max_width = STI_MAX_FB_HEIGHT;
127 	dev->mode_config.max_height = STI_MAX_FB_WIDTH;
128 
129 	dev->mode_config.funcs = &sti_mode_config_funcs;
130 }
131 
132 static int sti_load(struct drm_device *dev, unsigned long flags)
133 {
134 	struct sti_private *private;
135 	int ret;
136 
137 	private = kzalloc(sizeof(*private), GFP_KERNEL);
138 	if (!private) {
139 		DRM_ERROR("Failed to allocate private\n");
140 		return -ENOMEM;
141 	}
142 	dev->dev_private = (void *)private;
143 	private->drm_dev = dev;
144 
145 	mutex_init(&private->commit.lock);
146 	INIT_WORK(&private->commit.work, sti_atomic_work);
147 
148 	drm_mode_config_init(dev);
149 	drm_kms_helper_poll_init(dev);
150 
151 	sti_mode_config_init(dev);
152 
153 	ret = component_bind_all(dev->dev, dev);
154 	if (ret) {
155 		drm_kms_helper_poll_fini(dev);
156 		drm_mode_config_cleanup(dev);
157 		kfree(private);
158 		return ret;
159 	}
160 
161 	drm_mode_config_reset(dev);
162 
163 #ifdef CONFIG_DRM_STI_FBDEV
164 	drm_fbdev_cma_init(dev, 32,
165 			   dev->mode_config.num_crtc,
166 			   dev->mode_config.num_connector);
167 #endif
168 	return 0;
169 }
170 
171 static const struct file_operations sti_driver_fops = {
172 	.owner = THIS_MODULE,
173 	.open = drm_open,
174 	.mmap = drm_gem_cma_mmap,
175 	.poll = drm_poll,
176 	.read = drm_read,
177 	.unlocked_ioctl = drm_ioctl,
178 #ifdef CONFIG_COMPAT
179 	.compat_ioctl = drm_compat_ioctl,
180 #endif
181 	.release = drm_release,
182 };
183 
184 static struct dma_buf *sti_gem_prime_export(struct drm_device *dev,
185 					    struct drm_gem_object *obj,
186 					    int flags)
187 {
188 	/* we want to be able to write in mmapped buffer */
189 	flags |= O_RDWR;
190 	return drm_gem_prime_export(dev, obj, flags);
191 }
192 
193 static struct drm_driver sti_driver = {
194 	.driver_features = DRIVER_HAVE_IRQ | DRIVER_MODESET |
195 	    DRIVER_GEM | DRIVER_PRIME,
196 	.load = sti_load,
197 	.gem_free_object = drm_gem_cma_free_object,
198 	.gem_vm_ops = &drm_gem_cma_vm_ops,
199 	.dumb_create = drm_gem_cma_dumb_create,
200 	.dumb_map_offset = drm_gem_cma_dumb_map_offset,
201 	.dumb_destroy = drm_gem_dumb_destroy,
202 	.fops = &sti_driver_fops,
203 
204 	.get_vblank_counter = drm_vblank_count,
205 	.enable_vblank = sti_crtc_enable_vblank,
206 	.disable_vblank = sti_crtc_disable_vblank,
207 
208 	.prime_handle_to_fd = drm_gem_prime_handle_to_fd,
209 	.prime_fd_to_handle = drm_gem_prime_fd_to_handle,
210 	.gem_prime_export = sti_gem_prime_export,
211 	.gem_prime_import = drm_gem_prime_import,
212 	.gem_prime_get_sg_table = drm_gem_cma_prime_get_sg_table,
213 	.gem_prime_import_sg_table = drm_gem_cma_prime_import_sg_table,
214 	.gem_prime_vmap = drm_gem_cma_prime_vmap,
215 	.gem_prime_vunmap = drm_gem_cma_prime_vunmap,
216 	.gem_prime_mmap = drm_gem_cma_prime_mmap,
217 
218 	.name = DRIVER_NAME,
219 	.desc = DRIVER_DESC,
220 	.date = DRIVER_DATE,
221 	.major = DRIVER_MAJOR,
222 	.minor = DRIVER_MINOR,
223 };
224 
225 static int compare_of(struct device *dev, void *data)
226 {
227 	return dev->of_node == data;
228 }
229 
230 static int sti_bind(struct device *dev)
231 {
232 	return drm_platform_init(&sti_driver, to_platform_device(dev));
233 }
234 
235 static void sti_unbind(struct device *dev)
236 {
237 	drm_put_dev(dev_get_drvdata(dev));
238 }
239 
240 static const struct component_master_ops sti_ops = {
241 	.bind = sti_bind,
242 	.unbind = sti_unbind,
243 };
244 
245 static int sti_platform_probe(struct platform_device *pdev)
246 {
247 	struct device *dev = &pdev->dev;
248 	struct device_node *node = dev->of_node;
249 	struct device_node *child_np;
250 	struct component_match *match = NULL;
251 
252 	dma_set_coherent_mask(dev, DMA_BIT_MASK(32));
253 
254 	of_platform_populate(node, NULL, NULL, dev);
255 
256 	child_np = of_get_next_available_child(node, NULL);
257 
258 	while (child_np) {
259 		component_match_add(dev, &match, compare_of, child_np);
260 		of_node_put(child_np);
261 		child_np = of_get_next_available_child(node, child_np);
262 	}
263 
264 	return component_master_add_with_match(dev, &sti_ops, match);
265 }
266 
267 static int sti_platform_remove(struct platform_device *pdev)
268 {
269 	component_master_del(&pdev->dev, &sti_ops);
270 	of_platform_depopulate(&pdev->dev);
271 
272 	return 0;
273 }
274 
275 static const struct of_device_id sti_dt_ids[] = {
276 	{ .compatible = "st,sti-display-subsystem", },
277 	{ /* end node */ },
278 };
279 MODULE_DEVICE_TABLE(of, sti_dt_ids);
280 
281 static struct platform_driver sti_platform_driver = {
282 	.probe = sti_platform_probe,
283 	.remove = sti_platform_remove,
284 	.driver = {
285 		.name = DRIVER_NAME,
286 		.of_match_table = sti_dt_ids,
287 	},
288 };
289 
290 module_platform_driver(sti_platform_driver);
291 
292 MODULE_AUTHOR("Benjamin Gaignard <benjamin.gaignard@st.com>");
293 MODULE_DESCRIPTION("STMicroelectronics SoC DRM driver");
294 MODULE_LICENSE("GPL");
295