1 /*
2  * Copyright (C) Fuzhou Rockchip Electronics Co.Ltd
3  * Author:Mark Yao <mark.yao@rock-chips.com>
4  *
5  * This software is licensed under the terms of the GNU General Public
6  * License version 2, as published by the Free Software Foundation, and
7  * may be copied, distributed, and modified under those terms.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  */
14 
15 #include <drm/drm.h>
16 #include <drm/drmP.h>
17 #include <drm/drm_gem.h>
18 #include <drm/drm_vma_manager.h>
19 
20 #include <linux/dma-attrs.h>
21 
22 #include "rockchip_drm_drv.h"
23 #include "rockchip_drm_gem.h"
24 
25 static int rockchip_gem_alloc_buf(struct rockchip_gem_object *rk_obj)
26 {
27 	struct drm_gem_object *obj = &rk_obj->base;
28 	struct drm_device *drm = obj->dev;
29 
30 	init_dma_attrs(&rk_obj->dma_attrs);
31 	dma_set_attr(DMA_ATTR_WRITE_COMBINE, &rk_obj->dma_attrs);
32 
33 	/* TODO(djkurtz): Use DMA_ATTR_NO_KERNEL_MAPPING except for fbdev */
34 	rk_obj->kvaddr = dma_alloc_attrs(drm->dev, obj->size,
35 					 &rk_obj->dma_addr, GFP_KERNEL,
36 					 &rk_obj->dma_attrs);
37 	if (!rk_obj->kvaddr) {
38 		DRM_ERROR("failed to allocate %#x byte dma buffer", obj->size);
39 		return -ENOMEM;
40 	}
41 
42 	return 0;
43 }
44 
45 static void rockchip_gem_free_buf(struct rockchip_gem_object *rk_obj)
46 {
47 	struct drm_gem_object *obj = &rk_obj->base;
48 	struct drm_device *drm = obj->dev;
49 
50 	dma_free_attrs(drm->dev, obj->size, rk_obj->kvaddr, rk_obj->dma_addr,
51 		       &rk_obj->dma_attrs);
52 }
53 
54 int rockchip_gem_mmap_buf(struct drm_gem_object *obj,
55 			  struct vm_area_struct *vma)
56 {
57 	struct rockchip_gem_object *rk_obj = to_rockchip_obj(obj);
58 	struct drm_device *drm = obj->dev;
59 	unsigned long vm_size;
60 
61 	vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
62 	vm_size = vma->vm_end - vma->vm_start;
63 
64 	if (vm_size > obj->size)
65 		return -EINVAL;
66 
67 	return dma_mmap_attrs(drm->dev, vma, rk_obj->kvaddr, rk_obj->dma_addr,
68 			     obj->size, &rk_obj->dma_attrs);
69 }
70 
71 /* drm driver mmap file operations */
72 int rockchip_gem_mmap(struct file *filp, struct vm_area_struct *vma)
73 {
74 	struct drm_file *priv = filp->private_data;
75 	struct drm_device *dev = priv->minor->dev;
76 	struct drm_gem_object *obj;
77 	struct drm_vma_offset_node *node;
78 	int ret;
79 
80 	if (drm_device_is_unplugged(dev))
81 		return -ENODEV;
82 
83 	mutex_lock(&dev->struct_mutex);
84 
85 	node = drm_vma_offset_exact_lookup(dev->vma_offset_manager,
86 					   vma->vm_pgoff,
87 					   vma_pages(vma));
88 	if (!node) {
89 		mutex_unlock(&dev->struct_mutex);
90 		DRM_ERROR("failed to find vma node.\n");
91 		return -EINVAL;
92 	} else if (!drm_vma_node_is_allowed(node, filp)) {
93 		mutex_unlock(&dev->struct_mutex);
94 		return -EACCES;
95 	}
96 
97 	obj = container_of(node, struct drm_gem_object, vma_node);
98 	ret = rockchip_gem_mmap_buf(obj, vma);
99 
100 	mutex_unlock(&dev->struct_mutex);
101 
102 	return ret;
103 }
104 
105 struct rockchip_gem_object *
106 	rockchip_gem_create_object(struct drm_device *drm, unsigned int size)
107 {
108 	struct rockchip_gem_object *rk_obj;
109 	struct drm_gem_object *obj;
110 	int ret;
111 
112 	size = round_up(size, PAGE_SIZE);
113 
114 	rk_obj = kzalloc(sizeof(*rk_obj), GFP_KERNEL);
115 	if (!rk_obj)
116 		return ERR_PTR(-ENOMEM);
117 
118 	obj = &rk_obj->base;
119 
120 	drm_gem_private_object_init(drm, obj, size);
121 
122 	ret = rockchip_gem_alloc_buf(rk_obj);
123 	if (ret)
124 		goto err_free_rk_obj;
125 
126 	return rk_obj;
127 
128 err_free_rk_obj:
129 	kfree(rk_obj);
130 	return ERR_PTR(ret);
131 }
132 
133 /*
134  * rockchip_gem_free_object - (struct drm_driver)->gem_free_object callback
135  * function
136  */
137 void rockchip_gem_free_object(struct drm_gem_object *obj)
138 {
139 	struct rockchip_gem_object *rk_obj;
140 
141 	drm_gem_free_mmap_offset(obj);
142 
143 	rk_obj = to_rockchip_obj(obj);
144 
145 	rockchip_gem_free_buf(rk_obj);
146 
147 	kfree(rk_obj);
148 }
149 
150 /*
151  * rockchip_gem_create_with_handle - allocate an object with the given
152  * size and create a gem handle on it
153  *
154  * returns a struct rockchip_gem_object* on success or ERR_PTR values
155  * on failure.
156  */
157 static struct rockchip_gem_object *
158 rockchip_gem_create_with_handle(struct drm_file *file_priv,
159 				struct drm_device *drm, unsigned int size,
160 				unsigned int *handle)
161 {
162 	struct rockchip_gem_object *rk_obj;
163 	struct drm_gem_object *obj;
164 	int ret;
165 
166 	rk_obj = rockchip_gem_create_object(drm, size);
167 	if (IS_ERR(rk_obj))
168 		return ERR_CAST(rk_obj);
169 
170 	obj = &rk_obj->base;
171 
172 	/*
173 	 * allocate a id of idr table where the obj is registered
174 	 * and handle has the id what user can see.
175 	 */
176 	ret = drm_gem_handle_create(file_priv, obj, handle);
177 	if (ret)
178 		goto err_handle_create;
179 
180 	/* drop reference from allocate - handle holds it now. */
181 	drm_gem_object_unreference_unlocked(obj);
182 
183 	return rk_obj;
184 
185 err_handle_create:
186 	rockchip_gem_free_object(obj);
187 
188 	return ERR_PTR(ret);
189 }
190 
191 int rockchip_gem_dumb_map_offset(struct drm_file *file_priv,
192 				 struct drm_device *dev, uint32_t handle,
193 				 uint64_t *offset)
194 {
195 	struct drm_gem_object *obj;
196 	int ret;
197 
198 	mutex_lock(&dev->struct_mutex);
199 
200 	obj = drm_gem_object_lookup(dev, file_priv, handle);
201 	if (!obj) {
202 		DRM_ERROR("failed to lookup gem object.\n");
203 		ret = -EINVAL;
204 		goto unlock;
205 	}
206 
207 	ret = drm_gem_create_mmap_offset(obj);
208 	if (ret)
209 		goto out;
210 
211 	*offset = drm_vma_node_offset_addr(&obj->vma_node);
212 	DRM_DEBUG_KMS("offset = 0x%llx\n", *offset);
213 
214 out:
215 	drm_gem_object_unreference(obj);
216 unlock:
217 	mutex_unlock(&dev->struct_mutex);
218 	return ret;
219 }
220 
221 /*
222  * rockchip_gem_dumb_create - (struct drm_driver)->dumb_create callback
223  * function
224  *
225  * This aligns the pitch and size arguments to the minimum required. wrap
226  * this into your own function if you need bigger alignment.
227  */
228 int rockchip_gem_dumb_create(struct drm_file *file_priv,
229 			     struct drm_device *dev,
230 			     struct drm_mode_create_dumb *args)
231 {
232 	struct rockchip_gem_object *rk_obj;
233 	int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
234 
235 	/*
236 	 * align to 64 bytes since Mali requires it.
237 	 */
238 	min_pitch = ALIGN(min_pitch, 64);
239 
240 	if (args->pitch < min_pitch)
241 		args->pitch = min_pitch;
242 
243 	if (args->size < args->pitch * args->height)
244 		args->size = args->pitch * args->height;
245 
246 	rk_obj = rockchip_gem_create_with_handle(file_priv, dev, args->size,
247 						 &args->handle);
248 
249 	return PTR_ERR_OR_ZERO(rk_obj);
250 }
251 
252 /*
253  * Allocate a sg_table for this GEM object.
254  * Note: Both the table's contents, and the sg_table itself must be freed by
255  *       the caller.
256  * Returns a pointer to the newly allocated sg_table, or an ERR_PTR() error.
257  */
258 struct sg_table *rockchip_gem_prime_get_sg_table(struct drm_gem_object *obj)
259 {
260 	struct rockchip_gem_object *rk_obj = to_rockchip_obj(obj);
261 	struct drm_device *drm = obj->dev;
262 	struct sg_table *sgt;
263 	int ret;
264 
265 	sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
266 	if (!sgt)
267 		return ERR_PTR(-ENOMEM);
268 
269 	ret = dma_get_sgtable_attrs(drm->dev, sgt, rk_obj->kvaddr,
270 				    rk_obj->dma_addr, obj->size,
271 				    &rk_obj->dma_attrs);
272 	if (ret) {
273 		DRM_ERROR("failed to allocate sgt, %d\n", ret);
274 		kfree(sgt);
275 		return ERR_PTR(ret);
276 	}
277 
278 	return sgt;
279 }
280 
281 void *rockchip_gem_prime_vmap(struct drm_gem_object *obj)
282 {
283 	struct rockchip_gem_object *rk_obj = to_rockchip_obj(obj);
284 
285 	return rk_obj->kvaddr;
286 }
287 
288 void rockchip_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
289 {
290 	/* Nothing to do */
291 }
292