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  */
calculate_curbe_offsets(struct brw_context * brw)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  */
brw_upload_cs_urb_state(struct brw_context * brw)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
brw_upload_constant_buffer(struct brw_context * brw)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 struct brw_vertex_program *vp =
188       brw_vertex_program_const(brw->vertex_program);
189    const GLuint sz = brw->curbe.total_size;
190    const GLuint bufsz = sz * 16 * sizeof(GLfloat);
191    GLfloat *buf;
192    GLuint i;
193    gl_clip_plane *clip_planes;
194 
195    if (sz == 0) {
196       brw->curbe.last_bufsz  = 0;
197       goto emit;
198    }
199 
200    buf = brw->curbe.next_buf;
201 
202    /* fragment shader constants */
203    if (brw->curbe.wm_size) {
204       GLuint offset = brw->curbe.wm_start * 16;
205 
206       /* copy float constants */
207       for (i = 0; i < brw->wm.prog_data->nr_params; i++) {
208 	 buf[offset + i] = *brw->wm.prog_data->param[i];
209       }
210    }
211 
212 
213    /* When using the old VS backend, the clipplanes are actually delivered to
214     * both CLIP and VS units.  VS uses them to calculate the outcode bitmasks.
215     *
216     * When using the new VS backend, it is responsible for setting up its own
217     * clipplane constants if it needs them.  This results in a slight waste of
218     * of curbe space, but the advantage is that the new VS backend can use its
219     * general-purpose uniform layout code to store the clipplanes.
220     */
221    if (brw->curbe.clip_size) {
222       GLuint offset = brw->curbe.clip_start * 16;
223       GLuint j;
224 
225       /* If any planes are going this way, send them all this way:
226        */
227       for (i = 0; i < 6; i++) {
228 	 buf[offset + i * 4 + 0] = fixed_plane[i][0];
229 	 buf[offset + i * 4 + 1] = fixed_plane[i][1];
230 	 buf[offset + i * 4 + 2] = fixed_plane[i][2];
231 	 buf[offset + i * 4 + 3] = fixed_plane[i][3];
232       }
233 
234       /* Clip planes: _NEW_TRANSFORM plus _NEW_PROJECTION to get to
235        * clip-space:
236        */
237       clip_planes = brw_select_clip_planes(ctx);
238       for (j = 0; j < MAX_CLIP_PLANES; j++) {
239 	 if (ctx->Transform.ClipPlanesEnabled & (1<<j)) {
240 	    buf[offset + i * 4 + 0] = clip_planes[j][0];
241 	    buf[offset + i * 4 + 1] = clip_planes[j][1];
242 	    buf[offset + i * 4 + 2] = clip_planes[j][2];
243 	    buf[offset + i * 4 + 3] = clip_planes[j][3];
244 	    i++;
245 	 }
246       }
247    }
248 
249    /* vertex shader constants */
250    if (brw->curbe.vs_size) {
251       GLuint offset = brw->curbe.vs_start * 16;
252       GLuint nr = brw->vs.prog_data->nr_params / 4;
253 
254       if (brw->vs.prog_data->uses_new_param_layout) {
255 	 for (i = 0; i < brw->vs.prog_data->nr_params; i++) {
256 	    buf[offset + i] = *brw->vs.prog_data->param[i];
257 	 }
258       } else {
259 	 /* Load the subset of push constants that will get used when
260 	  * we also have a pull constant buffer.
261 	  */
262 	 for (i = 0; i < vp->program.Base.Parameters->NumParameters; i++) {
263 	    if (brw->vs.constant_map[i] != -1) {
264 	       assert(brw->vs.constant_map[i] <= nr);
265 	       memcpy(buf + offset + brw->vs.constant_map[i] * 4,
266 		      vp->program.Base.Parameters->ParameterValues[i],
267 		      4 * sizeof(float));
268 	    }
269 	 }
270       }
271    }
272 
273    if (0) {
274       for (i = 0; i < sz*16; i+=4)
275 	 printf("curbe %d.%d: %f %f %f %f\n", i/8, i&4,
276 		buf[i+0], buf[i+1], buf[i+2], buf[i+3]);
277 
278       printf("last_buf %p buf %p sz %d/%d cmp %d\n",
279 	     brw->curbe.last_buf, buf,
280 	     bufsz, brw->curbe.last_bufsz,
281 	     brw->curbe.last_buf ? memcmp(buf, brw->curbe.last_buf, bufsz) : -1);
282    }
283 
284    if (brw->curbe.curbe_bo != NULL &&
285        bufsz == brw->curbe.last_bufsz &&
286        memcmp(buf, brw->curbe.last_buf, bufsz) == 0) {
287       /* constants have not changed */
288    } else {
289       /* Update the record of what our last set of constants was.  We
290        * don't just flip the pointers because we don't fill in the
291        * data in the padding between the entries.
292        */
293       memcpy(brw->curbe.last_buf, buf, bufsz);
294       brw->curbe.last_bufsz = bufsz;
295 
296       if (brw->curbe.curbe_bo != NULL &&
297 	  brw->curbe.curbe_next_offset + bufsz > brw->curbe.curbe_bo->size)
298       {
299 	 drm_intel_gem_bo_unmap_gtt(brw->curbe.curbe_bo);
300 	 drm_intel_bo_unreference(brw->curbe.curbe_bo);
301 	 brw->curbe.curbe_bo = NULL;
302       }
303 
304       if (brw->curbe.curbe_bo == NULL) {
305 	 /* Allocate a single page for CURBE entries for this batchbuffer.
306 	  * They're generally around 64b.
307 	  */
308 	 brw->curbe.curbe_bo = drm_intel_bo_alloc(brw->intel.bufmgr, "CURBE",
309 						  4096, 1 << 6);
310 	 brw->curbe.curbe_next_offset = 0;
311 	 drm_intel_gem_bo_map_gtt(brw->curbe.curbe_bo);
312 	 assert(bufsz < 4096);
313       }
314 
315       brw->curbe.curbe_offset = brw->curbe.curbe_next_offset;
316       brw->curbe.curbe_next_offset += bufsz;
317       brw->curbe.curbe_next_offset = ALIGN(brw->curbe.curbe_next_offset, 64);
318 
319       /* Copy data to the buffer:
320        */
321       memcpy(brw->curbe.curbe_bo->virtual + brw->curbe.curbe_offset,
322 	     buf,
323 	     bufsz);
324    }
325 
326    /* Because this provokes an action (ie copy the constants into the
327     * URB), it shouldn't be shortcircuited if identical to the
328     * previous time - because eg. the urb destination may have
329     * changed, or the urb contents different to last time.
330     *
331     * Note that the data referred to is actually copied internally,
332     * not just used in place according to passed pointer.
333     *
334     * It appears that the CS unit takes care of using each available
335     * URB entry (Const URB Entry == CURBE) in turn, and issuing
336     * flushes as necessary when doublebuffering of CURBEs isn't
337     * possible.
338     */
339 
340 emit:
341    BEGIN_BATCH(2);
342    if (brw->curbe.total_size == 0) {
343       OUT_BATCH((CMD_CONST_BUFFER << 16) | (2 - 2));
344       OUT_BATCH(0);
345    } else {
346       OUT_BATCH((CMD_CONST_BUFFER << 16) | (1 << 8) | (2 - 2));
347       OUT_RELOC(brw->curbe.curbe_bo,
348 		I915_GEM_DOMAIN_INSTRUCTION, 0,
349 		(brw->curbe.total_size - 1) + brw->curbe.curbe_offset);
350    }
351    ADVANCE_BATCH();
352 }
353 
354 /* This tracked state is unique in that the state it monitors varies
355  * dynamically depending on the parameters tracked by the fragment and
356  * vertex programs.  This is the template used as a starting point,
357  * each context will maintain a copy of this internally and update as
358  * required.
359  */
360 const struct brw_tracked_state brw_constant_buffer = {
361    .dirty = {
362       .mesa = _NEW_PROGRAM_CONSTANTS,
363       .brw  = (BRW_NEW_FRAGMENT_PROGRAM |
364 	       BRW_NEW_VERTEX_PROGRAM |
365 	       BRW_NEW_URB_FENCE | /* Implicit - hardware requires this, not used above */
366 	       BRW_NEW_PSP | /* Implicit - hardware requires this, not used above */
367 	       BRW_NEW_CURBE_OFFSETS |
368 	       BRW_NEW_BATCH),
369       .cache = (CACHE_NEW_WM_PROG)
370    },
371    .emit = brw_upload_constant_buffer,
372 };
373 
374