1 /*
2 Copyright (C) Intel Corp. 2006. All Rights Reserved.
3 Intel funded Tungsten Graphics 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 <keithw@vmware.com>
30 */
31
32
33
34 #include "intel_batchbuffer.h"
35 #include "brw_context.h"
36 #include "brw_state.h"
37 #include "brw_defines.h"
38
39 #define VS 0
40 #define GS 1
41 #define CLP 2
42 #define SF 3
43 #define CS 4
44
45 /** @file brw_urb.c
46 *
47 * Manages the division of the URB space between the various fixed-function
48 * units.
49 *
50 * See the Thread Initiation Management section of the GEN4 B-Spec, and
51 * the individual *_STATE structures for restrictions on numbers of
52 * entries and threads.
53 */
54
55 /*
56 * Generally, a unit requires a min_nr_entries based on how many entries
57 * it produces before the downstream unit gets unblocked and can use and
58 * dereference some of its handles.
59 *
60 * The SF unit preallocates a PUE at the start of thread dispatch, and only
61 * uses that one. So it requires one entry per thread.
62 *
63 * For CLIP, the SF unit will hold the previous primitive while the
64 * next is getting assembled, meaning that linestrips require 3 CLIP VUEs
65 * (vertices) to ensure continued processing, trifans require 4, and tristrips
66 * require 5. There can be 1 or 2 threads, and each has the same requirement.
67 *
68 * GS has the same requirement as CLIP, but it never handles tristrips,
69 * so we can lower the minimum to 4 for the POLYGONs (trifans) it produces.
70 * We only run it single-threaded.
71 *
72 * For VS, the number of entries may be 8, 12, 16, or 32 (or 64 on G4X).
73 * Each thread processes 2 preallocated VUEs (vertices) at a time, and they
74 * get streamed down as soon as threads processing earlier vertices get
75 * theirs accepted.
76 *
77 * Each unit will take the number of URB entries we give it (based on the
78 * entry size calculated in brw_vs_emit.c for VUEs, brw_sf_emit.c for PUEs,
79 * and brw_curbe.c for the CURBEs) and decide its maximum number of
80 * threads it can support based on that. in brw_*_state.c.
81 *
82 * XXX: Are the min_entry_size numbers useful?
83 * XXX: Verify min_nr_entries, esp for VS.
84 * XXX: Verify SF min_entry_size.
85 */
86 static const struct {
87 GLuint min_nr_entries;
88 GLuint preferred_nr_entries;
89 GLuint min_entry_size;
90 GLuint max_entry_size;
91 } limits[CS+1] = {
92 { 16, 32, 1, 5 }, /* vs */
93 { 4, 8, 1, 5 }, /* gs */
94 { 5, 10, 1, 5 }, /* clp */
95 { 1, 8, 1, 12 }, /* sf */
96 { 1, 4, 1, 32 } /* cs */
97 };
98
99
check_urb_layout(struct brw_context * brw)100 static bool check_urb_layout(struct brw_context *brw)
101 {
102 brw->urb.vs_start = 0;
103 brw->urb.gs_start = brw->urb.nr_vs_entries * brw->urb.vsize;
104 brw->urb.clip_start = brw->urb.gs_start + brw->urb.nr_gs_entries * brw->urb.vsize;
105 brw->urb.sf_start = brw->urb.clip_start + brw->urb.nr_clip_entries * brw->urb.vsize;
106 brw->urb.cs_start = brw->urb.sf_start + brw->urb.nr_sf_entries * brw->urb.sfsize;
107
108 return brw->urb.cs_start + brw->urb.nr_cs_entries *
109 brw->urb.csize <= brw->urb.size;
110 }
111
112 /* Most minimal update, forces re-emit of URB fence packet after GS
113 * unit turned on/off.
114 */
recalculate_urb_fence(struct brw_context * brw)115 static void recalculate_urb_fence( struct brw_context *brw )
116 {
117 GLuint csize = brw->curbe.total_size;
118 GLuint vsize = brw_vue_prog_data(brw->vs.base.prog_data)->urb_entry_size;
119 GLuint sfsize = brw->sf.prog_data->urb_entry_size;
120
121 if (csize < limits[CS].min_entry_size)
122 csize = limits[CS].min_entry_size;
123
124 if (vsize < limits[VS].min_entry_size)
125 vsize = limits[VS].min_entry_size;
126
127 if (sfsize < limits[SF].min_entry_size)
128 sfsize = limits[SF].min_entry_size;
129
130 if (brw->urb.vsize < vsize ||
131 brw->urb.sfsize < sfsize ||
132 brw->urb.csize < csize ||
133 (brw->urb.constrained && (brw->urb.vsize > vsize ||
134 brw->urb.sfsize > sfsize ||
135 brw->urb.csize > csize))) {
136
137
138 brw->urb.csize = csize;
139 brw->urb.sfsize = sfsize;
140 brw->urb.vsize = vsize;
141
142 brw->urb.nr_vs_entries = limits[VS].preferred_nr_entries;
143 brw->urb.nr_gs_entries = limits[GS].preferred_nr_entries;
144 brw->urb.nr_clip_entries = limits[CLP].preferred_nr_entries;
145 brw->urb.nr_sf_entries = limits[SF].preferred_nr_entries;
146 brw->urb.nr_cs_entries = limits[CS].preferred_nr_entries;
147
148 brw->urb.constrained = 0;
149
150 if (brw->gen == 5) {
151 brw->urb.nr_vs_entries = 128;
152 brw->urb.nr_sf_entries = 48;
153 if (check_urb_layout(brw)) {
154 goto done;
155 } else {
156 brw->urb.constrained = 1;
157 brw->urb.nr_vs_entries = limits[VS].preferred_nr_entries;
158 brw->urb.nr_sf_entries = limits[SF].preferred_nr_entries;
159 }
160 } else if (brw->is_g4x) {
161 brw->urb.nr_vs_entries = 64;
162 if (check_urb_layout(brw)) {
163 goto done;
164 } else {
165 brw->urb.constrained = 1;
166 brw->urb.nr_vs_entries = limits[VS].preferred_nr_entries;
167 }
168 }
169
170 if (!check_urb_layout(brw)) {
171 brw->urb.nr_vs_entries = limits[VS].min_nr_entries;
172 brw->urb.nr_gs_entries = limits[GS].min_nr_entries;
173 brw->urb.nr_clip_entries = limits[CLP].min_nr_entries;
174 brw->urb.nr_sf_entries = limits[SF].min_nr_entries;
175 brw->urb.nr_cs_entries = limits[CS].min_nr_entries;
176
177 /* Mark us as operating with constrained nr_entries, so that next
178 * time we recalculate we'll resize the fences in the hope of
179 * escaping constrained mode and getting back to normal performance.
180 */
181 brw->urb.constrained = 1;
182
183 if (!check_urb_layout(brw)) {
184 /* This is impossible, given the maximal sizes of urb
185 * entries and the values for minimum nr of entries
186 * provided above.
187 */
188 fprintf(stderr, "couldn't calculate URB layout!\n");
189 exit(1);
190 }
191
192 if (unlikely(INTEL_DEBUG & (DEBUG_URB|DEBUG_PERF)))
193 fprintf(stderr, "URB CONSTRAINED\n");
194 }
195
196 done:
197 if (unlikely(INTEL_DEBUG & DEBUG_URB))
198 fprintf(stderr,
199 "URB fence: %d ..VS.. %d ..GS.. %d ..CLP.. %d ..SF.. %d ..CS.. %d\n",
200 brw->urb.vs_start,
201 brw->urb.gs_start,
202 brw->urb.clip_start,
203 brw->urb.sf_start,
204 brw->urb.cs_start,
205 brw->urb.size);
206
207 brw->ctx.NewDriverState |= BRW_NEW_URB_FENCE;
208 }
209 }
210
211
212 const struct brw_tracked_state brw_recalculate_urb_fence = {
213 .dirty = {
214 .mesa = 0,
215 .brw = BRW_NEW_BLORP |
216 BRW_NEW_CURBE_OFFSETS |
217 BRW_NEW_SF_PROG_DATA |
218 BRW_NEW_VS_PROG_DATA,
219 },
220 .emit = recalculate_urb_fence
221 };
222
223
224
225
226
brw_upload_urb_fence(struct brw_context * brw)227 void brw_upload_urb_fence(struct brw_context *brw)
228 {
229 struct brw_urb_fence uf;
230 memset(&uf, 0, sizeof(uf));
231
232 uf.header.opcode = CMD_URB_FENCE;
233 uf.header.length = sizeof(uf)/4-2;
234 uf.header.vs_realloc = 1;
235 uf.header.gs_realloc = 1;
236 uf.header.clp_realloc = 1;
237 uf.header.sf_realloc = 1;
238 uf.header.vfe_realloc = 1;
239 uf.header.cs_realloc = 1;
240
241 /* The ordering below is correct, not the layout in the
242 * instruction.
243 *
244 * There are 256/384 urb reg pairs in total.
245 */
246 uf.bits0.vs_fence = brw->urb.gs_start;
247 uf.bits0.gs_fence = brw->urb.clip_start;
248 uf.bits0.clp_fence = brw->urb.sf_start;
249 uf.bits1.sf_fence = brw->urb.cs_start;
250 uf.bits1.cs_fence = brw->urb.size;
251
252 /* erratum: URB_FENCE must not cross a 64byte cacheline */
253 if ((USED_BATCH(brw->batch) & 15) > 12) {
254 int pad = 16 - (USED_BATCH(brw->batch) & 15);
255 do
256 *brw->batch.map_next++ = MI_NOOP;
257 while (--pad);
258 }
259
260 BRW_BATCH_STRUCT(brw, &uf);
261 }
262