1 /*
2  *
3  * (C) COPYRIGHT 2010-2017 ARM Limited. All rights reserved.
4  *
5  * This program is free software and is provided to you under the terms of the
6  * GNU General Public License version 2 as published by the Free Software
7  * Foundation, and any use by you of this program is subject to the terms
8  * of such GNU licence.
9  *
10  * A copy of the licence is included with the program, and can also be obtained
11  * from Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
12  * Boston, MA  02110-1301, USA.
13  *
14  */
15 
16 
17 
18 #ifndef _KBASE_FENCE_H_
19 #define _KBASE_FENCE_H_
20 
21 /*
22  * mali_kbase_fence.[hc] has common fence code used by both
23  * - CONFIG_MALI_DMA_FENCE - implicit DMA fences
24  * - CONFIG_SYNC_FILE      - explicit fences beginning with 4.9 kernel
25  */
26 
27 #if defined(CONFIG_MALI_DMA_FENCE) || defined(CONFIG_SYNC_FILE)
28 
29 #include <linux/list.h>
30 #include "mali_kbase_fence_defs.h"
31 #include "mali_kbase.h"
32 
33 #if (LINUX_VERSION_CODE < KERNEL_VERSION(4, 10, 0))
34 extern const struct fence_ops kbase_fence_ops;
35 #else
36 extern const struct dma_fence_ops kbase_fence_ops;
37 #endif
38 
39 /**
40 * struct kbase_fence_cb - Mali dma-fence callback data struct
41 * @fence_cb: Callback function
42 * @katom:    Pointer to katom that is waiting on this callback
43 * @fence:    Pointer to the fence object on which this callback is waiting
44 * @node:     List head for linking this callback to the katom
45 */
46 struct kbase_fence_cb {
47 #if (LINUX_VERSION_CODE < KERNEL_VERSION(4, 10, 0))
48 	struct fence_cb fence_cb;
49 	struct fence *fence;
50 #else
51 	struct dma_fence_cb fence_cb;
52 	struct dma_fence *fence;
53 #endif
54 	struct kbase_jd_atom *katom;
55 	struct list_head node;
56 };
57 
58 /**
59  * kbase_fence_out_new() - Creates a new output fence and puts it on the atom
60  * @katom: Atom to create an output fence for
61  *
62  * return: A new fence object on success, NULL on failure.
63  */
64 #if (LINUX_VERSION_CODE < KERNEL_VERSION(4, 10, 0))
65 struct fence *kbase_fence_out_new(struct kbase_jd_atom *katom);
66 #else
67 struct dma_fence *kbase_fence_out_new(struct kbase_jd_atom *katom);
68 #endif
69 
70 #if defined(CONFIG_SYNC_FILE)
71 /**
72  * kbase_fence_fence_in_set() - Assign input fence to atom
73  * @katom: Atom to assign input fence to
74  * @fence: Input fence to assign to atom
75  *
76  * This function will take ownership of one fence reference!
77  */
78 #define kbase_fence_fence_in_set(katom, fence) \
79 	do { \
80 		WARN_ON((katom)->dma_fence.fence_in); \
81 		(katom)->dma_fence.fence_in = fence; \
82 	} while (0)
83 #endif
84 
85 /**
86  * kbase_fence_out_remove() - Removes the output fence from atom
87  * @katom: Atom to remove output fence for
88  *
89  * This will also release the reference to this fence which the atom keeps
90  */
kbase_fence_out_remove(struct kbase_jd_atom *katom)91 static inline void kbase_fence_out_remove(struct kbase_jd_atom *katom)
92 {
93 	if (katom->dma_fence.fence) {
94 		dma_fence_put(katom->dma_fence.fence);
95 		katom->dma_fence.fence = NULL;
96 	}
97 }
98 
99 #if defined(CONFIG_SYNC_FILE)
100 /**
101  * kbase_fence_out_remove() - Removes the input fence from atom
102  * @katom: Atom to remove input fence for
103  *
104  * This will also release the reference to this fence which the atom keeps
105  */
kbase_fence_in_remove(struct kbase_jd_atom *katom)106 static inline void kbase_fence_in_remove(struct kbase_jd_atom *katom)
107 {
108 	if (katom->dma_fence.fence_in) {
109 		dma_fence_put(katom->dma_fence.fence_in);
110 		katom->dma_fence.fence_in = NULL;
111 	}
112 }
113 #endif
114 
115 /**
116  * kbase_fence_out_is_ours() - Check if atom has a valid fence created by us
117  * @katom: Atom to check output fence for
118  *
119  * Return: true if fence exists and is valid, otherwise false
120  */
kbase_fence_out_is_ours(struct kbase_jd_atom *katom)121 static inline bool kbase_fence_out_is_ours(struct kbase_jd_atom *katom)
122 {
123 	return katom->dma_fence.fence &&
124 				katom->dma_fence.fence->ops == &kbase_fence_ops;
125 }
126 
127 /**
128  * kbase_fence_out_signal() - Signal output fence of atom
129  * @katom: Atom to signal output fence for
130  * @status: Status to signal with (0 for success, < 0 for error)
131  *
132  * Return: 0 on success, < 0 on error
133  */
kbase_fence_out_signal(struct kbase_jd_atom *katom, int status)134 static inline int kbase_fence_out_signal(struct kbase_jd_atom *katom,
135 					 int status)
136 {
137 	if (status) {
138 #if (KERNEL_VERSION(4, 10, 0) > LINUX_VERSION_CODE && \
139 	  KERNEL_VERSION(4, 9, 68) <= LINUX_VERSION_CODE)
140 		fence_set_error(katom->dma_fence.fence, status);
141 #elif (KERNEL_VERSION(4, 11, 0) <= LINUX_VERSION_CODE)
142 		dma_fence_set_error(katom->dma_fence.fence, status);
143 #else
144 		katom->dma_fence.fence->status = status;
145 #endif
146 	}
147 	return dma_fence_signal(katom->dma_fence.fence);
148 }
149 
150 /**
151  * kbase_fence_add_callback() - Add callback on @fence to block @katom
152  * @katom: Pointer to katom that will be blocked by @fence
153  * @fence: Pointer to fence on which to set up the callback
154  * @callback: Pointer to function to be called when fence is signaled
155  *
156  * Caller needs to hold a reference to @fence when calling this function, and
157  * the caller is responsible for releasing that reference.  An additional
158  * reference to @fence will be taken when the callback was successfully set up
159  * and @fence needs to be kept valid until the callback has been called and
160  * cleanup have been done.
161  *
162  * Return: 0 on success: fence was either already signaled, or callback was
163  * set up. Negative error code is returned on error.
164  */
165 #if (LINUX_VERSION_CODE < KERNEL_VERSION(4, 10, 0))
166 int kbase_fence_add_callback(struct kbase_jd_atom *katom,
167 			     struct fence *fence,
168 			     fence_func_t callback);
169 #else
170 int kbase_fence_add_callback(struct kbase_jd_atom *katom,
171 			     struct dma_fence *fence,
172 			     dma_fence_func_t callback);
173 #endif
174 
175 /**
176  * kbase_fence_dep_count_set() - Set dep_count value on atom to specified value
177  * @katom: Atom to set dep_count for
178  * @val: value to set dep_count to
179  *
180  * The dep_count is available to the users of this module so that they can
181  * synchronize completion of the wait with cancellation and adding of more
182  * callbacks. For instance, a user could do the following:
183  *
184  * dep_count set to 1
185  * callback #1 added, dep_count is increased to 2
186  *                             callback #1 happens, dep_count decremented to 1
187  *                             since dep_count > 0, no completion is done
188  * callback #2 is added, dep_count is increased to 2
189  * dep_count decremented to 1
190  *                             callback #2 happens, dep_count decremented to 0
191  *                             since dep_count now is zero, completion executes
192  *
193  * The dep_count can also be used to make sure that the completion only
194  * executes once. This is typically done by setting dep_count to -1 for the
195  * thread that takes on this responsibility.
196  */
197 static inline void
kbase_fence_dep_count_set(struct kbase_jd_atom *katom, int val)198 kbase_fence_dep_count_set(struct kbase_jd_atom *katom, int val)
199 {
200 	atomic_set(&katom->dma_fence.dep_count, val);
201 }
202 
203 /**
204  * kbase_fence_dep_count_dec_and_test() - Decrements dep_count
205  * @katom: Atom to decrement dep_count for
206  *
207  * See @kbase_fence_dep_count_set for general description about dep_count
208  *
209  * Return: true if value was decremented to zero, otherwise false
210  */
211 static inline bool
kbase_fence_dep_count_dec_and_test(struct kbase_jd_atom *katom)212 kbase_fence_dep_count_dec_and_test(struct kbase_jd_atom *katom)
213 {
214 	return atomic_dec_and_test(&katom->dma_fence.dep_count);
215 }
216 
217 /**
218  * kbase_fence_dep_count_read() - Returns the current dep_count value
219  * @katom: Pointer to katom
220  *
221  * See @kbase_fence_dep_count_set for general description about dep_count
222  *
223  * Return: The current dep_count value
224  */
kbase_fence_dep_count_read(struct kbase_jd_atom *katom)225 static inline int kbase_fence_dep_count_read(struct kbase_jd_atom *katom)
226 {
227 	return atomic_read(&katom->dma_fence.dep_count);
228 }
229 
230 /**
231  * kbase_fence_free_callbacks() - Free dma-fence callbacks on a katom
232  * @katom: Pointer to katom
233  *
234  * This function will free all fence callbacks on the katom's list of
235  * callbacks. Callbacks that have not yet been called, because their fence
236  * hasn't yet signaled, will first be removed from the fence.
237  *
238  * Locking: katom->dma_fence.callbacks list assumes jctx.lock is held.
239  *
240  * Return: true if dep_count reached 0, otherwise false.
241  */
242 bool kbase_fence_free_callbacks(struct kbase_jd_atom *katom);
243 
244 #if defined(CONFIG_SYNC_FILE)
245 /**
246  * kbase_fence_in_get() - Retrieve input fence for atom.
247  * @katom: Atom to get input fence from
248  *
249  * A ref will be taken for the fence, so use @kbase_fence_put() to release it
250  *
251  * Return: The fence, or NULL if there is no input fence for atom
252  */
253 #define kbase_fence_in_get(katom) dma_fence_get((katom)->dma_fence.fence_in)
254 #endif
255 
256 /**
257  * kbase_fence_out_get() - Retrieve output fence for atom.
258  * @katom: Atom to get output fence from
259  *
260  * A ref will be taken for the fence, so use @kbase_fence_put() to release it
261  *
262  * Return: The fence, or NULL if there is no output fence for atom
263  */
264 #define kbase_fence_out_get(katom) dma_fence_get((katom)->dma_fence.fence)
265 
266 /**
267  * kbase_fence_put() - Releases a reference to a fence
268  * @fence: Fence to release reference for.
269  */
270 #define kbase_fence_put(fence) dma_fence_put(fence)
271 
272 
273 #endif /* CONFIG_MALI_DMA_FENCE || defined(CONFIG_SYNC_FILE */
274 
275 #endif /* _KBASE_FENCE_H_ */
276