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 				  bool alloc_kmap)
27 {
28 	struct drm_gem_object *obj = &rk_obj->base;
29 	struct drm_device *drm = obj->dev;
30 
31 	init_dma_attrs(&rk_obj->dma_attrs);
32 	dma_set_attr(DMA_ATTR_WRITE_COMBINE, &rk_obj->dma_attrs);
33 
34 	if (!alloc_kmap)
35 		dma_set_attr(DMA_ATTR_NO_KERNEL_MAPPING, &rk_obj->dma_attrs);
36 
37 	rk_obj->kvaddr = dma_alloc_attrs(drm->dev, obj->size,
38 					 &rk_obj->dma_addr, GFP_KERNEL,
39 					 &rk_obj->dma_attrs);
40 	if (!rk_obj->kvaddr) {
41 		DRM_ERROR("failed to allocate %#x byte dma buffer", obj->size);
42 		return -ENOMEM;
43 	}
44 
45 	return 0;
46 }
47 
48 static void rockchip_gem_free_buf(struct rockchip_gem_object *rk_obj)
49 {
50 	struct drm_gem_object *obj = &rk_obj->base;
51 	struct drm_device *drm = obj->dev;
52 
53 	dma_free_attrs(drm->dev, obj->size, rk_obj->kvaddr, rk_obj->dma_addr,
54 		       &rk_obj->dma_attrs);
55 }
56 
57 static int rockchip_drm_gem_object_mmap(struct drm_gem_object *obj,
58 					struct vm_area_struct *vma)
59 
60 {
61 	int ret;
62 	struct rockchip_gem_object *rk_obj = to_rockchip_obj(obj);
63 	struct drm_device *drm = obj->dev;
64 
65 	/*
66 	 * dma_alloc_attrs() allocated a struct page table for rk_obj, so clear
67 	 * VM_PFNMAP flag that was set by drm_gem_mmap_obj()/drm_gem_mmap().
68 	 */
69 	vma->vm_flags &= ~VM_PFNMAP;
70 
71 	ret = dma_mmap_attrs(drm->dev, vma, rk_obj->kvaddr, rk_obj->dma_addr,
72 			     obj->size, &rk_obj->dma_attrs);
73 	if (ret)
74 		drm_gem_vm_close(vma);
75 
76 	return ret;
77 }
78 
79 int rockchip_gem_mmap_buf(struct drm_gem_object *obj,
80 			  struct vm_area_struct *vma)
81 {
82 	struct drm_device *drm = obj->dev;
83 	int ret;
84 
85 	mutex_lock(&drm->struct_mutex);
86 	ret = drm_gem_mmap_obj(obj, obj->size, vma);
87 	mutex_unlock(&drm->struct_mutex);
88 	if (ret)
89 		return ret;
90 
91 	return rockchip_drm_gem_object_mmap(obj, vma);
92 }
93 
94 /* drm driver mmap file operations */
95 int rockchip_gem_mmap(struct file *filp, struct vm_area_struct *vma)
96 {
97 	struct drm_gem_object *obj;
98 	int ret;
99 
100 	ret = drm_gem_mmap(filp, vma);
101 	if (ret)
102 		return ret;
103 
104 	obj = vma->vm_private_data;
105 
106 	return rockchip_drm_gem_object_mmap(obj, vma);
107 }
108 
109 struct rockchip_gem_object *
110 	rockchip_gem_create_object(struct drm_device *drm, unsigned int size,
111 				   bool alloc_kmap)
112 {
113 	struct rockchip_gem_object *rk_obj;
114 	struct drm_gem_object *obj;
115 	int ret;
116 
117 	size = round_up(size, PAGE_SIZE);
118 
119 	rk_obj = kzalloc(sizeof(*rk_obj), GFP_KERNEL);
120 	if (!rk_obj)
121 		return ERR_PTR(-ENOMEM);
122 
123 	obj = &rk_obj->base;
124 
125 	drm_gem_private_object_init(drm, obj, size);
126 
127 	ret = rockchip_gem_alloc_buf(rk_obj, alloc_kmap);
128 	if (ret)
129 		goto err_free_rk_obj;
130 
131 	return rk_obj;
132 
133 err_free_rk_obj:
134 	kfree(rk_obj);
135 	return ERR_PTR(ret);
136 }
137 
138 /*
139  * rockchip_gem_free_object - (struct drm_driver)->gem_free_object callback
140  * function
141  */
142 void rockchip_gem_free_object(struct drm_gem_object *obj)
143 {
144 	struct rockchip_gem_object *rk_obj;
145 
146 	drm_gem_free_mmap_offset(obj);
147 
148 	rk_obj = to_rockchip_obj(obj);
149 
150 	rockchip_gem_free_buf(rk_obj);
151 
152 	kfree(rk_obj);
153 }
154 
155 /*
156  * rockchip_gem_create_with_handle - allocate an object with the given
157  * size and create a gem handle on it
158  *
159  * returns a struct rockchip_gem_object* on success or ERR_PTR values
160  * on failure.
161  */
162 static struct rockchip_gem_object *
163 rockchip_gem_create_with_handle(struct drm_file *file_priv,
164 				struct drm_device *drm, unsigned int size,
165 				unsigned int *handle)
166 {
167 	struct rockchip_gem_object *rk_obj;
168 	struct drm_gem_object *obj;
169 	int ret;
170 
171 	rk_obj = rockchip_gem_create_object(drm, size, false);
172 	if (IS_ERR(rk_obj))
173 		return ERR_CAST(rk_obj);
174 
175 	obj = &rk_obj->base;
176 
177 	/*
178 	 * allocate a id of idr table where the obj is registered
179 	 * and handle has the id what user can see.
180 	 */
181 	ret = drm_gem_handle_create(file_priv, obj, handle);
182 	if (ret)
183 		goto err_handle_create;
184 
185 	/* drop reference from allocate - handle holds it now. */
186 	drm_gem_object_unreference_unlocked(obj);
187 
188 	return rk_obj;
189 
190 err_handle_create:
191 	rockchip_gem_free_object(obj);
192 
193 	return ERR_PTR(ret);
194 }
195 
196 int rockchip_gem_dumb_map_offset(struct drm_file *file_priv,
197 				 struct drm_device *dev, uint32_t handle,
198 				 uint64_t *offset)
199 {
200 	struct drm_gem_object *obj;
201 	int ret;
202 
203 	obj = drm_gem_object_lookup(dev, file_priv, handle);
204 	if (!obj) {
205 		DRM_ERROR("failed to lookup gem object.\n");
206 		return -EINVAL;
207 	}
208 
209 	ret = drm_gem_create_mmap_offset(obj);
210 	if (ret)
211 		goto out;
212 
213 	*offset = drm_vma_node_offset_addr(&obj->vma_node);
214 	DRM_DEBUG_KMS("offset = 0x%llx\n", *offset);
215 
216 out:
217 	drm_gem_object_unreference_unlocked(obj);
218 
219 	return 0;
220 }
221 
222 /*
223  * rockchip_gem_dumb_create - (struct drm_driver)->dumb_create callback
224  * function
225  *
226  * This aligns the pitch and size arguments to the minimum required. wrap
227  * this into your own function if you need bigger alignment.
228  */
229 int rockchip_gem_dumb_create(struct drm_file *file_priv,
230 			     struct drm_device *dev,
231 			     struct drm_mode_create_dumb *args)
232 {
233 	struct rockchip_gem_object *rk_obj;
234 	int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
235 
236 	/*
237 	 * align to 64 bytes since Mali requires it.
238 	 */
239 	min_pitch = ALIGN(min_pitch, 64);
240 
241 	if (args->pitch < min_pitch)
242 		args->pitch = min_pitch;
243 
244 	if (args->size < args->pitch * args->height)
245 		args->size = args->pitch * args->height;
246 
247 	rk_obj = rockchip_gem_create_with_handle(file_priv, dev, args->size,
248 						 &args->handle);
249 
250 	return PTR_ERR_OR_ZERO(rk_obj);
251 }
252 
253 /*
254  * Allocate a sg_table for this GEM object.
255  * Note: Both the table's contents, and the sg_table itself must be freed by
256  *       the caller.
257  * Returns a pointer to the newly allocated sg_table, or an ERR_PTR() error.
258  */
259 struct sg_table *rockchip_gem_prime_get_sg_table(struct drm_gem_object *obj)
260 {
261 	struct rockchip_gem_object *rk_obj = to_rockchip_obj(obj);
262 	struct drm_device *drm = obj->dev;
263 	struct sg_table *sgt;
264 	int ret;
265 
266 	sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
267 	if (!sgt)
268 		return ERR_PTR(-ENOMEM);
269 
270 	ret = dma_get_sgtable_attrs(drm->dev, sgt, rk_obj->kvaddr,
271 				    rk_obj->dma_addr, obj->size,
272 				    &rk_obj->dma_attrs);
273 	if (ret) {
274 		DRM_ERROR("failed to allocate sgt, %d\n", ret);
275 		kfree(sgt);
276 		return ERR_PTR(ret);
277 	}
278 
279 	return sgt;
280 }
281 
282 void *rockchip_gem_prime_vmap(struct drm_gem_object *obj)
283 {
284 	struct rockchip_gem_object *rk_obj = to_rockchip_obj(obj);
285 
286 	if (dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, &rk_obj->dma_attrs))
287 		return NULL;
288 
289 	return rk_obj->kvaddr;
290 }
291 
292 void rockchip_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
293 {
294 	/* Nothing to do */
295 }
296