i965: Remove some stale comments about the brw_constant_buffer atom.
[mesa.git] / src / mesa / drivers / dri / i965 / brw_curbe.c
1 /*
2 Copyright (C) Intel Corp. 2006. All Rights Reserved.
3 Intel funded Tungsten Graphics (http://www.tungstengraphics.com) to
4 develop this 3D driver.
5
6 Permission is hereby granted, free of charge, to any person obtaining
7 a copy of this software and associated documentation files (the
8 "Software"), to deal in the Software without restriction, including
9 without limitation the rights to use, copy, modify, merge, publish,
10 distribute, sublicense, and/or sell copies of the Software, and to
11 permit persons to whom the Software is furnished to do so, subject to
12 the following conditions:
13
14 The above copyright notice and this permission notice (including the
15 next paragraph) shall be included in all copies or substantial
16 portions of the Software.
17
18 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
19 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
21 IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
22 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
23 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
24 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25
26 **********************************************************************/
27 /*
28 * Authors:
29 * Keith Whitwell <keith@tungstengraphics.com>
30 */
31
32
33
34 #include "main/glheader.h"
35 #include "main/context.h"
36 #include "main/macros.h"
37 #include "main/enums.h"
38 #include "program/prog_parameter.h"
39 #include "program/prog_print.h"
40 #include "program/prog_statevars.h"
41 #include "intel_batchbuffer.h"
42 #include "intel_regions.h"
43 #include "brw_context.h"
44 #include "brw_defines.h"
45 #include "brw_state.h"
46 #include "brw_util.h"
47
48
49 /**
50 * Partition the CURBE between the various users of constant values:
51 * Note that vertex and fragment shaders can now fetch constants out
52 * of constant buffers. We no longer allocatea block of the GRF for
53 * constants. That greatly reduces the demand for space in the CURBE.
54 * Some of the comments within are dated...
55 */
56 static void calculate_curbe_offsets( struct brw_context *brw )
57 {
58 struct gl_context *ctx = &brw->intel.ctx;
59 /* CACHE_NEW_WM_PROG */
60 const GLuint nr_fp_regs = (brw->wm.prog_data->nr_params + 15) / 16;
61
62 /* BRW_NEW_VERTEX_PROGRAM */
63 const GLuint nr_vp_regs = (brw->vs.prog_data->nr_params + 15) / 16;
64 GLuint nr_clip_regs = 0;
65 GLuint total_regs;
66
67 /* _NEW_TRANSFORM */
68 if (ctx->Transform.ClipPlanesEnabled) {
69 GLuint nr_planes = 6 + _mesa_bitcount_64(ctx->Transform.ClipPlanesEnabled);
70 nr_clip_regs = (nr_planes * 4 + 15) / 16;
71 }
72
73
74 total_regs = nr_fp_regs + nr_vp_regs + nr_clip_regs;
75
76 /* This can happen - what to do? Probably rather than falling
77 * back, the best thing to do is emit programs which code the
78 * constants as immediate values. Could do this either as a static
79 * cap on WM and VS, or adaptively.
80 *
81 * Unfortunately, this is currently dependent on the results of the
82 * program generation process (in the case of wm), so this would
83 * introduce the need to re-generate programs in the event of a
84 * curbe allocation failure.
85 */
86 /* Max size is 32 - just large enough to
87 * hold the 128 parameters allowed by
88 * the fragment and vertex program
89 * api's. It's not clear what happens
90 * when both VP and FP want to use 128
91 * parameters, though.
92 */
93 assert(total_regs <= 32);
94
95 /* Lazy resize:
96 */
97 if (nr_fp_regs > brw->curbe.wm_size ||
98 nr_vp_regs > brw->curbe.vs_size ||
99 nr_clip_regs != brw->curbe.clip_size ||
100 (total_regs < brw->curbe.total_size / 4 &&
101 brw->curbe.total_size > 16)) {
102
103 GLuint reg = 0;
104
105 /* Calculate a new layout:
106 */
107 reg = 0;
108 brw->curbe.wm_start = reg;
109 brw->curbe.wm_size = nr_fp_regs; reg += nr_fp_regs;
110 brw->curbe.clip_start = reg;
111 brw->curbe.clip_size = nr_clip_regs; reg += nr_clip_regs;
112 brw->curbe.vs_start = reg;
113 brw->curbe.vs_size = nr_vp_regs; reg += nr_vp_regs;
114 brw->curbe.total_size = reg;
115
116 if (0)
117 printf("curbe wm %d+%d clip %d+%d vs %d+%d\n",
118 brw->curbe.wm_start,
119 brw->curbe.wm_size,
120 brw->curbe.clip_start,
121 brw->curbe.clip_size,
122 brw->curbe.vs_start,
123 brw->curbe.vs_size );
124
125 brw->state.dirty.brw |= BRW_NEW_CURBE_OFFSETS;
126 }
127 }
128
129
130 const struct brw_tracked_state brw_curbe_offsets = {
131 .dirty = {
132 .mesa = _NEW_TRANSFORM,
133 .brw = BRW_NEW_VERTEX_PROGRAM | BRW_NEW_CONTEXT,
134 .cache = CACHE_NEW_WM_PROG
135 },
136 .emit = calculate_curbe_offsets
137 };
138
139
140
141
142 /* Define the number of curbes within CS's urb allocation. Multiple
143 * urb entries -> multiple curbes. These will be used by
144 * fixed-function hardware in a double-buffering scheme to avoid a
145 * pipeline stall each time the contents of the curbe is changed.
146 */
147 void brw_upload_cs_urb_state(struct brw_context *brw)
148 {
149 struct intel_context *intel = &brw->intel;
150
151 BEGIN_BATCH(2);
152 /* It appears that this is the state packet for the CS unit, ie. the
153 * urb entries detailed here are housed in the CS range from the
154 * URB_FENCE command.
155 */
156 OUT_BATCH(CMD_CS_URB_STATE << 16 | (2-2));
157
158 /* BRW_NEW_URB_FENCE */
159 if (brw->urb.csize == 0) {
160 OUT_BATCH(0);
161 } else {
162 /* BRW_NEW_URB_FENCE */
163 assert(brw->urb.nr_cs_entries);
164 OUT_BATCH((brw->urb.csize - 1) << 4 | brw->urb.nr_cs_entries);
165 }
166 CACHED_BATCH();
167 }
168
169 static GLfloat fixed_plane[6][4] = {
170 { 0, 0, -1, 1 },
171 { 0, 0, 1, 1 },
172 { 0, -1, 0, 1 },
173 { 0, 1, 0, 1 },
174 {-1, 0, 0, 1 },
175 { 1, 0, 0, 1 }
176 };
177
178 /* Upload a new set of constants. Too much variability to go into the
179 * cache mechanism, but maybe would benefit from a comparison against
180 * the current uploaded set of constants.
181 */
182 static void
183 brw_upload_constant_buffer(struct brw_context *brw)
184 {
185 struct intel_context *intel = &brw->intel;
186 struct gl_context *ctx = &intel->ctx;
187 const GLuint sz = brw->curbe.total_size;
188 const GLuint bufsz = sz * 16 * sizeof(GLfloat);
189 GLfloat *buf;
190 GLuint i;
191 gl_clip_plane *clip_planes;
192
193 if (sz == 0) {
194 brw->curbe.last_bufsz = 0;
195 goto emit;
196 }
197
198 buf = brw->curbe.next_buf;
199
200 /* fragment shader constants */
201 if (brw->curbe.wm_size) {
202 GLuint offset = brw->curbe.wm_start * 16;
203
204 /* copy float constants */
205 for (i = 0; i < brw->wm.prog_data->nr_params; i++) {
206 buf[offset + i] = *brw->wm.prog_data->param[i];
207 }
208 }
209
210 /* clipper constants */
211 if (brw->curbe.clip_size) {
212 GLuint offset = brw->curbe.clip_start * 16;
213 GLuint j;
214
215 /* If any planes are going this way, send them all this way:
216 */
217 for (i = 0; i < 6; i++) {
218 buf[offset + i * 4 + 0] = fixed_plane[i][0];
219 buf[offset + i * 4 + 1] = fixed_plane[i][1];
220 buf[offset + i * 4 + 2] = fixed_plane[i][2];
221 buf[offset + i * 4 + 3] = fixed_plane[i][3];
222 }
223
224 /* Clip planes: _NEW_TRANSFORM plus _NEW_PROJECTION to get to
225 * clip-space:
226 */
227 clip_planes = brw_select_clip_planes(ctx);
228 for (j = 0; j < MAX_CLIP_PLANES; j++) {
229 if (ctx->Transform.ClipPlanesEnabled & (1<<j)) {
230 buf[offset + i * 4 + 0] = clip_planes[j][0];
231 buf[offset + i * 4 + 1] = clip_planes[j][1];
232 buf[offset + i * 4 + 2] = clip_planes[j][2];
233 buf[offset + i * 4 + 3] = clip_planes[j][3];
234 i++;
235 }
236 }
237 }
238
239 /* vertex shader constants */
240 if (brw->curbe.vs_size) {
241 GLuint offset = brw->curbe.vs_start * 16;
242
243 for (i = 0; i < brw->vs.prog_data->nr_params; i++) {
244 buf[offset + i] = *brw->vs.prog_data->param[i];
245 }
246 }
247
248 if (0) {
249 for (i = 0; i < sz*16; i+=4)
250 printf("curbe %d.%d: %f %f %f %f\n", i/8, i&4,
251 buf[i+0], buf[i+1], buf[i+2], buf[i+3]);
252
253 printf("last_buf %p buf %p sz %d/%d cmp %d\n",
254 brw->curbe.last_buf, buf,
255 bufsz, brw->curbe.last_bufsz,
256 brw->curbe.last_buf ? memcmp(buf, brw->curbe.last_buf, bufsz) : -1);
257 }
258
259 if (brw->curbe.curbe_bo != NULL &&
260 bufsz == brw->curbe.last_bufsz &&
261 memcmp(buf, brw->curbe.last_buf, bufsz) == 0) {
262 /* constants have not changed */
263 } else {
264 /* Update the record of what our last set of constants was. We
265 * don't just flip the pointers because we don't fill in the
266 * data in the padding between the entries.
267 */
268 memcpy(brw->curbe.last_buf, buf, bufsz);
269 brw->curbe.last_bufsz = bufsz;
270
271 if (brw->curbe.curbe_bo != NULL &&
272 brw->curbe.curbe_next_offset + bufsz > brw->curbe.curbe_bo->size)
273 {
274 drm_intel_gem_bo_unmap_gtt(brw->curbe.curbe_bo);
275 drm_intel_bo_unreference(brw->curbe.curbe_bo);
276 brw->curbe.curbe_bo = NULL;
277 }
278
279 if (brw->curbe.curbe_bo == NULL) {
280 /* Allocate a single page for CURBE entries for this batchbuffer.
281 * They're generally around 64b.
282 */
283 brw->curbe.curbe_bo = drm_intel_bo_alloc(brw->intel.bufmgr, "CURBE",
284 4096, 1 << 6);
285 brw->curbe.curbe_next_offset = 0;
286 drm_intel_gem_bo_map_gtt(brw->curbe.curbe_bo);
287 assert(bufsz < 4096);
288 }
289
290 brw->curbe.curbe_offset = brw->curbe.curbe_next_offset;
291 brw->curbe.curbe_next_offset += bufsz;
292 brw->curbe.curbe_next_offset = ALIGN(brw->curbe.curbe_next_offset, 64);
293
294 /* Copy data to the buffer:
295 */
296 memcpy(brw->curbe.curbe_bo->virtual + brw->curbe.curbe_offset,
297 buf,
298 bufsz);
299 }
300
301 /* Because this provokes an action (ie copy the constants into the
302 * URB), it shouldn't be shortcircuited if identical to the
303 * previous time - because eg. the urb destination may have
304 * changed, or the urb contents different to last time.
305 *
306 * Note that the data referred to is actually copied internally,
307 * not just used in place according to passed pointer.
308 *
309 * It appears that the CS unit takes care of using each available
310 * URB entry (Const URB Entry == CURBE) in turn, and issuing
311 * flushes as necessary when doublebuffering of CURBEs isn't
312 * possible.
313 */
314
315 emit:
316 BEGIN_BATCH(2);
317 if (brw->curbe.total_size == 0) {
318 OUT_BATCH((CMD_CONST_BUFFER << 16) | (2 - 2));
319 OUT_BATCH(0);
320 } else {
321 OUT_BATCH((CMD_CONST_BUFFER << 16) | (1 << 8) | (2 - 2));
322 OUT_RELOC(brw->curbe.curbe_bo,
323 I915_GEM_DOMAIN_INSTRUCTION, 0,
324 (brw->curbe.total_size - 1) + brw->curbe.curbe_offset);
325 }
326 ADVANCE_BATCH();
327 }
328
329 const struct brw_tracked_state brw_constant_buffer = {
330 .dirty = {
331 .mesa = _NEW_PROGRAM_CONSTANTS,
332 .brw = (BRW_NEW_FRAGMENT_PROGRAM |
333 BRW_NEW_VERTEX_PROGRAM |
334 BRW_NEW_URB_FENCE | /* Implicit - hardware requires this, not used above */
335 BRW_NEW_PSP | /* Implicit - hardware requires this, not used above */
336 BRW_NEW_CURBE_OFFSETS |
337 BRW_NEW_BATCH),
338 .cache = (CACHE_NEW_WM_PROG)
339 },
340 .emit = brw_upload_constant_buffer,
341 };
342