xref: /openbmc/linux/drivers/gpu/drm/omapdrm/tcm.h (revision 4f3db074)
1 /*
2  * tcm.h
3  *
4  * TILER container manager specification and support functions for TI
5  * TILER driver.
6  *
7  * Author: Lajos Molnar <molnar@ti.com>
8  *
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  *
15  * * Redistributions of source code must retain the above copyright
16  *   notice, this list of conditions and the following disclaimer.
17  *
18  * * Redistributions in binary form must reproduce the above copyright
19  *   notice, this list of conditions and the following disclaimer in the
20  *   documentation and/or other materials provided with the distribution.
21  *
22  * * Neither the name of Texas Instruments Incorporated nor the names of
23  *   its contributors may be used to endorse or promote products derived
24  *   from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
27  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
28  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
30  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
31  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
32  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
33  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
34  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
35  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
36  * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 #ifndef TCM_H
40 #define TCM_H
41 
42 struct tcm;
43 
44 /* point */
45 struct tcm_pt {
46 	u16 x;
47 	u16 y;
48 };
49 
50 /* 1d or 2d area */
51 struct tcm_area {
52 	bool is2d;		/* whether area is 1d or 2d */
53 	struct tcm    *tcm;	/* parent */
54 	struct tcm_pt  p0;
55 	struct tcm_pt  p1;
56 };
57 
58 struct tcm {
59 	u16 width, height;	/* container dimensions */
60 	int lut_id;		/* Lookup table identifier */
61 
62 	unsigned int y_offset;	/* offset to use for y coordinates */
63 
64 	/* 'pvt' structure shall contain any tcm details (attr) along with
65 	linked list of allocated areas and mutex for mutually exclusive access
66 	to the list.  It may also contain copies of width and height to notice
67 	any changes to the publicly available width and height fields. */
68 	void *pvt;
69 
70 	/* function table */
71 	s32 (*reserve_2d)(struct tcm *tcm, u16 height, u16 width, u8 align,
72 			  struct tcm_area *area);
73 	s32 (*reserve_1d)(struct tcm *tcm, u32 slots, struct tcm_area *area);
74 	s32 (*free)      (struct tcm *tcm, struct tcm_area *area);
75 	void (*deinit)   (struct tcm *tcm);
76 };
77 
78 /*=============================================================================
79     BASIC TILER CONTAINER MANAGER INTERFACE
80 =============================================================================*/
81 
82 /*
83  * NOTE:
84  *
85  * Since some basic parameter checking is done outside the TCM algorithms,
86  * TCM implementation do NOT have to check the following:
87  *
88  *   area pointer is NULL
89  *   width and height fits within container
90  *   number of pages is more than the size of the container
91  *
92  */
93 
94 struct tcm *sita_init(u16 width, u16 height, struct tcm_pt *attr);
95 
96 
97 /**
98  * Deinitialize tiler container manager.
99  *
100  * @param tcm	Pointer to container manager.
101  *
102  * @return 0 on success, non-0 error value on error.  The call
103  *	   should free as much memory as possible and meaningful
104  *	   even on failure.  Some error codes: -ENODEV: invalid
105  *	   manager.
106  */
107 static inline void tcm_deinit(struct tcm *tcm)
108 {
109 	if (tcm)
110 		tcm->deinit(tcm);
111 }
112 
113 /**
114  * Reserves a 2D area in the container.
115  *
116  * @param tcm		Pointer to container manager.
117  * @param height	Height(in pages) of area to be reserved.
118  * @param width		Width(in pages) of area to be reserved.
119  * @param align		Alignment requirement for top-left corner of area. Not
120  *			all values may be supported by the container manager,
121  *			but it must support 0 (1), 32 and 64.
122  *			0 value is equivalent to 1.
123  * @param area		Pointer to where the reserved area should be stored.
124  *
125  * @return 0 on success.  Non-0 error code on failure.  Also,
126  *	   the tcm field of the area will be set to NULL on
127  *	   failure.  Some error codes: -ENODEV: invalid manager,
128  *	   -EINVAL: invalid area, -ENOMEM: not enough space for
129  *	    allocation.
130  */
131 static inline s32 tcm_reserve_2d(struct tcm *tcm, u16 width, u16 height,
132 				 u16 align, struct tcm_area *area)
133 {
134 	/* perform rudimentary error checking */
135 	s32 res = tcm  == NULL ? -ENODEV :
136 		(area == NULL || width == 0 || height == 0 ||
137 		 /* align must be a 2 power */
138 		 (align & (align - 1))) ? -EINVAL :
139 		(height > tcm->height || width > tcm->width) ? -ENOMEM : 0;
140 
141 	if (!res) {
142 		area->is2d = true;
143 		res = tcm->reserve_2d(tcm, height, width, align, area);
144 		area->tcm = res ? NULL : tcm;
145 	}
146 
147 	return res;
148 }
149 
150 /**
151  * Reserves a 1D area in the container.
152  *
153  * @param tcm		Pointer to container manager.
154  * @param slots		Number of (contiguous) slots to reserve.
155  * @param area		Pointer to where the reserved area should be stored.
156  *
157  * @return 0 on success.  Non-0 error code on failure.  Also,
158  *	   the tcm field of the area will be set to NULL on
159  *	   failure.  Some error codes: -ENODEV: invalid manager,
160  *	   -EINVAL: invalid area, -ENOMEM: not enough space for
161  *	    allocation.
162  */
163 static inline s32 tcm_reserve_1d(struct tcm *tcm, u32 slots,
164 				 struct tcm_area *area)
165 {
166 	/* perform rudimentary error checking */
167 	s32 res = tcm  == NULL ? -ENODEV :
168 		(area == NULL || slots == 0) ? -EINVAL :
169 		slots > (tcm->width * (u32) tcm->height) ? -ENOMEM : 0;
170 
171 	if (!res) {
172 		area->is2d = false;
173 		res = tcm->reserve_1d(tcm, slots, area);
174 		area->tcm = res ? NULL : tcm;
175 	}
176 
177 	return res;
178 }
179 
180 /**
181  * Free a previously reserved area from the container.
182  *
183  * @param area	Pointer to area reserved by a prior call to
184  *		tcm_reserve_1d or tcm_reserve_2d call, whether
185  *		it was successful or not. (Note: all fields of
186  *		the structure must match.)
187  *
188  * @return 0 on success.  Non-0 error code on failure.  Also, the tcm
189  *	   field of the area is set to NULL on success to avoid subsequent
190  *	   freeing.  This call will succeed even if supplying
191  *	   the area from a failed reserved call.
192  */
193 static inline s32 tcm_free(struct tcm_area *area)
194 {
195 	s32 res = 0; /* free succeeds by default */
196 
197 	if (area && area->tcm) {
198 		res = area->tcm->free(area->tcm, area);
199 		if (res == 0)
200 			area->tcm = NULL;
201 	}
202 
203 	return res;
204 }
205 
206 /*=============================================================================
207     HELPER FUNCTION FOR ANY TILER CONTAINER MANAGER
208 =============================================================================*/
209 
210 /**
211  * This method slices off the topmost 2D slice from the parent area, and stores
212  * it in the 'slice' parameter.  The 'parent' parameter will get modified to
213  * contain the remaining portion of the area.  If the whole parent area can
214  * fit in a 2D slice, its tcm pointer is set to NULL to mark that it is no
215  * longer a valid area.
216  *
217  * @param parent	Pointer to a VALID parent area that will get modified
218  * @param slice		Pointer to the slice area that will get modified
219  */
220 static inline void tcm_slice(struct tcm_area *parent, struct tcm_area *slice)
221 {
222 	*slice = *parent;
223 
224 	/* check if we need to slice */
225 	if (slice->tcm && !slice->is2d &&
226 		slice->p0.y != slice->p1.y &&
227 		(slice->p0.x || (slice->p1.x != slice->tcm->width - 1))) {
228 		/* set end point of slice (start always remains) */
229 		slice->p1.x = slice->tcm->width - 1;
230 		slice->p1.y = (slice->p0.x) ? slice->p0.y : slice->p1.y - 1;
231 		/* adjust remaining area */
232 		parent->p0.x = 0;
233 		parent->p0.y = slice->p1.y + 1;
234 	} else {
235 		/* mark this as the last slice */
236 		parent->tcm = NULL;
237 	}
238 }
239 
240 /* Verify if a tcm area is logically valid */
241 static inline bool tcm_area_is_valid(struct tcm_area *area)
242 {
243 	return area && area->tcm &&
244 		/* coordinate bounds */
245 		area->p1.x < area->tcm->width &&
246 		area->p1.y < area->tcm->height &&
247 		area->p0.y <= area->p1.y &&
248 		/* 1D coordinate relationship + p0.x check */
249 		((!area->is2d &&
250 		  area->p0.x < area->tcm->width &&
251 		  area->p0.x + area->p0.y * area->tcm->width <=
252 		  area->p1.x + area->p1.y * area->tcm->width) ||
253 		 /* 2D coordinate relationship */
254 		 (area->is2d &&
255 		  area->p0.x <= area->p1.x));
256 }
257 
258 /* see if a coordinate is within an area */
259 static inline bool __tcm_is_in(struct tcm_pt *p, struct tcm_area *a)
260 {
261 	u16 i;
262 
263 	if (a->is2d) {
264 		return p->x >= a->p0.x && p->x <= a->p1.x &&
265 		       p->y >= a->p0.y && p->y <= a->p1.y;
266 	} else {
267 		i = p->x + p->y * a->tcm->width;
268 		return i >= a->p0.x + a->p0.y * a->tcm->width &&
269 		       i <= a->p1.x + a->p1.y * a->tcm->width;
270 	}
271 }
272 
273 /* calculate area width */
274 static inline u16 __tcm_area_width(struct tcm_area *area)
275 {
276 	return area->p1.x - area->p0.x + 1;
277 }
278 
279 /* calculate area height */
280 static inline u16 __tcm_area_height(struct tcm_area *area)
281 {
282 	return area->p1.y - area->p0.y + 1;
283 }
284 
285 /* calculate number of slots in an area */
286 static inline u16 __tcm_sizeof(struct tcm_area *area)
287 {
288 	return area->is2d ?
289 		__tcm_area_width(area) * __tcm_area_height(area) :
290 		(area->p1.x - area->p0.x + 1) + (area->p1.y - area->p0.y) *
291 							area->tcm->width;
292 }
293 #define tcm_sizeof(area) __tcm_sizeof(&(area))
294 #define tcm_awidth(area) __tcm_area_width(&(area))
295 #define tcm_aheight(area) __tcm_area_height(&(area))
296 #define tcm_is_in(pt, area) __tcm_is_in(&(pt), &(area))
297 
298 /* limit a 1D area to the first N pages */
299 static inline s32 tcm_1d_limit(struct tcm_area *a, u32 num_pg)
300 {
301 	if (__tcm_sizeof(a) < num_pg)
302 		return -ENOMEM;
303 	if (!num_pg)
304 		return -EINVAL;
305 
306 	a->p1.x = (a->p0.x + num_pg - 1) % a->tcm->width;
307 	a->p1.y = a->p0.y + ((a->p0.x + num_pg - 1) / a->tcm->width);
308 	return 0;
309 }
310 
311 /**
312  * Iterate through 2D slices of a valid area. Behaves
313  * syntactically as a for(;;) statement.
314  *
315  * @param var		Name of a local variable of type 'struct
316  *			tcm_area *' that will get modified to
317  *			contain each slice.
318  * @param area		Pointer to the VALID parent area. This
319  *			structure will not get modified
320  *			throughout the loop.
321  *
322  */
323 #define tcm_for_each_slice(var, area, safe) \
324 	for (safe = area, \
325 	     tcm_slice(&safe, &var); \
326 	     var.tcm; tcm_slice(&safe, &var))
327 
328 #endif
329