xref: /openbmc/linux/drivers/gpu/drm/omapdrm/tcm.h (revision d3964221)
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 	spinlock_t lock;
65 	unsigned long *bitmap;
66 	size_t map_size;
67 
68 	/* function table */
69 	s32 (*reserve_2d)(struct tcm *tcm, u16 height, u16 width, u16 align,
70 			  int16_t offset, uint16_t slot_bytes,
71 			  struct tcm_area *area);
72 	s32 (*reserve_1d)(struct tcm *tcm, u32 slots, struct tcm_area *area);
73 	s32 (*free)(struct tcm *tcm, struct tcm_area *area);
74 	void (*deinit)(struct tcm *tcm);
75 };
76 
77 /*=============================================================================
78     BASIC TILER CONTAINER MANAGER INTERFACE
79 =============================================================================*/
80 
81 /*
82  * NOTE:
83  *
84  * Since some basic parameter checking is done outside the TCM algorithms,
85  * TCM implementation do NOT have to check the following:
86  *
87  *   area pointer is NULL
88  *   width and height fits within container
89  *   number of pages is more than the size of the container
90  *
91  */
92 
93 struct tcm *sita_init(u16 width, u16 height);
94 
95 
96 /**
97  * Deinitialize tiler container manager.
98  *
99  * @param tcm	Pointer to container manager.
100  *
101  * @return 0 on success, non-0 error value on error.  The call
102  *	   should free as much memory as possible and meaningful
103  *	   even on failure.  Some error codes: -ENODEV: invalid
104  *	   manager.
105  */
106 static inline void tcm_deinit(struct tcm *tcm)
107 {
108 	if (tcm)
109 		tcm->deinit(tcm);
110 }
111 
112 /**
113  * Reserves a 2D area in the container.
114  *
115  * @param tcm		Pointer to container manager.
116  * @param height	Height(in pages) of area to be reserved.
117  * @param width		Width(in pages) of area to be reserved.
118  * @param align		Alignment requirement for top-left corner of area. Not
119  *			all values may be supported by the container manager,
120  *			but it must support 0 (1), 32 and 64.
121  *			0 value is equivalent to 1.
122  * @param offset	Offset requirement, in bytes.  This is the offset
123  *			from a 4KiB aligned virtual address.
124  * @param slot_bytes	Width of slot in bytes
125  * @param area		Pointer to where the reserved area should be stored.
126  *
127  * @return 0 on success.  Non-0 error code on failure.  Also,
128  *	   the tcm field of the area will be set to NULL on
129  *	   failure.  Some error codes: -ENODEV: invalid manager,
130  *	   -EINVAL: invalid area, -ENOMEM: not enough space for
131  *	    allocation.
132  */
133 static inline s32 tcm_reserve_2d(struct tcm *tcm, u16 width, u16 height,
134 				u16 align, int16_t offset, uint16_t slot_bytes,
135 				struct tcm_area *area)
136 {
137 	/* perform rudimentary error checking */
138 	s32 res = tcm  == NULL ? -ENODEV :
139 		(area == NULL || width == 0 || height == 0 ||
140 		 /* align must be a 2 power */
141 		 (align & (align - 1))) ? -EINVAL :
142 		(height > tcm->height || width > tcm->width) ? -ENOMEM : 0;
143 
144 	if (!res) {
145 		area->is2d = true;
146 		res = tcm->reserve_2d(tcm, height, width, align, offset,
147 					slot_bytes, area);
148 		area->tcm = res ? NULL : tcm;
149 	}
150 
151 	return res;
152 }
153 
154 /**
155  * Reserves a 1D area in the container.
156  *
157  * @param tcm		Pointer to container manager.
158  * @param slots		Number of (contiguous) slots to reserve.
159  * @param area		Pointer to where the reserved area should be stored.
160  *
161  * @return 0 on success.  Non-0 error code on failure.  Also,
162  *	   the tcm field of the area will be set to NULL on
163  *	   failure.  Some error codes: -ENODEV: invalid manager,
164  *	   -EINVAL: invalid area, -ENOMEM: not enough space for
165  *	    allocation.
166  */
167 static inline s32 tcm_reserve_1d(struct tcm *tcm, u32 slots,
168 				 struct tcm_area *area)
169 {
170 	/* perform rudimentary error checking */
171 	s32 res = tcm  == NULL ? -ENODEV :
172 		(area == NULL || slots == 0) ? -EINVAL :
173 		slots > (tcm->width * (u32) tcm->height) ? -ENOMEM : 0;
174 
175 	if (!res) {
176 		area->is2d = false;
177 		res = tcm->reserve_1d(tcm, slots, area);
178 		area->tcm = res ? NULL : tcm;
179 	}
180 
181 	return res;
182 }
183 
184 /**
185  * Free a previously reserved area from the container.
186  *
187  * @param area	Pointer to area reserved by a prior call to
188  *		tcm_reserve_1d or tcm_reserve_2d call, whether
189  *		it was successful or not. (Note: all fields of
190  *		the structure must match.)
191  *
192  * @return 0 on success.  Non-0 error code on failure.  Also, the tcm
193  *	   field of the area is set to NULL on success to avoid subsequent
194  *	   freeing.  This call will succeed even if supplying
195  *	   the area from a failed reserved call.
196  */
197 static inline s32 tcm_free(struct tcm_area *area)
198 {
199 	s32 res = 0; /* free succeeds by default */
200 
201 	if (area && area->tcm) {
202 		res = area->tcm->free(area->tcm, area);
203 		if (res == 0)
204 			area->tcm = NULL;
205 	}
206 
207 	return res;
208 }
209 
210 /*=============================================================================
211     HELPER FUNCTION FOR ANY TILER CONTAINER MANAGER
212 =============================================================================*/
213 
214 /**
215  * This method slices off the topmost 2D slice from the parent area, and stores
216  * it in the 'slice' parameter.  The 'parent' parameter will get modified to
217  * contain the remaining portion of the area.  If the whole parent area can
218  * fit in a 2D slice, its tcm pointer is set to NULL to mark that it is no
219  * longer a valid area.
220  *
221  * @param parent	Pointer to a VALID parent area that will get modified
222  * @param slice		Pointer to the slice area that will get modified
223  */
224 static inline void tcm_slice(struct tcm_area *parent, struct tcm_area *slice)
225 {
226 	*slice = *parent;
227 
228 	/* check if we need to slice */
229 	if (slice->tcm && !slice->is2d &&
230 		slice->p0.y != slice->p1.y &&
231 		(slice->p0.x || (slice->p1.x != slice->tcm->width - 1))) {
232 		/* set end point of slice (start always remains) */
233 		slice->p1.x = slice->tcm->width - 1;
234 		slice->p1.y = (slice->p0.x) ? slice->p0.y : slice->p1.y - 1;
235 		/* adjust remaining area */
236 		parent->p0.x = 0;
237 		parent->p0.y = slice->p1.y + 1;
238 	} else {
239 		/* mark this as the last slice */
240 		parent->tcm = NULL;
241 	}
242 }
243 
244 /* Verify if a tcm area is logically valid */
245 static inline bool tcm_area_is_valid(struct tcm_area *area)
246 {
247 	return area && area->tcm &&
248 		/* coordinate bounds */
249 		area->p1.x < area->tcm->width &&
250 		area->p1.y < area->tcm->height &&
251 		area->p0.y <= area->p1.y &&
252 		/* 1D coordinate relationship + p0.x check */
253 		((!area->is2d &&
254 		  area->p0.x < area->tcm->width &&
255 		  area->p0.x + area->p0.y * area->tcm->width <=
256 		  area->p1.x + area->p1.y * area->tcm->width) ||
257 		 /* 2D coordinate relationship */
258 		 (area->is2d &&
259 		  area->p0.x <= area->p1.x));
260 }
261 
262 /* see if a coordinate is within an area */
263 static inline bool __tcm_is_in(struct tcm_pt *p, struct tcm_area *a)
264 {
265 	u16 i;
266 
267 	if (a->is2d) {
268 		return p->x >= a->p0.x && p->x <= a->p1.x &&
269 		       p->y >= a->p0.y && p->y <= a->p1.y;
270 	} else {
271 		i = p->x + p->y * a->tcm->width;
272 		return i >= a->p0.x + a->p0.y * a->tcm->width &&
273 		       i <= a->p1.x + a->p1.y * a->tcm->width;
274 	}
275 }
276 
277 /* calculate area width */
278 static inline u16 __tcm_area_width(struct tcm_area *area)
279 {
280 	return area->p1.x - area->p0.x + 1;
281 }
282 
283 /* calculate area height */
284 static inline u16 __tcm_area_height(struct tcm_area *area)
285 {
286 	return area->p1.y - area->p0.y + 1;
287 }
288 
289 /* calculate number of slots in an area */
290 static inline u16 __tcm_sizeof(struct tcm_area *area)
291 {
292 	return area->is2d ?
293 		__tcm_area_width(area) * __tcm_area_height(area) :
294 		(area->p1.x - area->p0.x + 1) + (area->p1.y - area->p0.y) *
295 							area->tcm->width;
296 }
297 #define tcm_sizeof(area) __tcm_sizeof(&(area))
298 #define tcm_awidth(area) __tcm_area_width(&(area))
299 #define tcm_aheight(area) __tcm_area_height(&(area))
300 #define tcm_is_in(pt, area) __tcm_is_in(&(pt), &(area))
301 
302 /* limit a 1D area to the first N pages */
303 static inline s32 tcm_1d_limit(struct tcm_area *a, u32 num_pg)
304 {
305 	if (__tcm_sizeof(a) < num_pg)
306 		return -ENOMEM;
307 	if (!num_pg)
308 		return -EINVAL;
309 
310 	a->p1.x = (a->p0.x + num_pg - 1) % a->tcm->width;
311 	a->p1.y = a->p0.y + ((a->p0.x + num_pg - 1) / a->tcm->width);
312 	return 0;
313 }
314 
315 /**
316  * Iterate through 2D slices of a valid area. Behaves
317  * syntactically as a for(;;) statement.
318  *
319  * @param var		Name of a local variable of type 'struct
320  *			tcm_area *' that will get modified to
321  *			contain each slice.
322  * @param area		Pointer to the VALID parent area. This
323  *			structure will not get modified
324  *			throughout the loop.
325  *
326  */
327 #define tcm_for_each_slice(var, area, safe) \
328 	for (safe = area, \
329 	     tcm_slice(&safe, &var); \
330 	     var.tcm; tcm_slice(&safe, &var))
331 
332 #endif
333