iris_binder.c revision 9f464c52 
1/*
2 * Copyright © 2018 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included
12 * in all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
15 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
19 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
20 * DEALINGS IN THE SOFTWARE.
21 */
22
23/**
24 * @file iris_binder.c
25 *
26 * Shader programs refer to most resources via integer handles.  These are
27 * indexes (BTIs) into a "Binding Table", which is simply a list of pointers
28 * to SURFACE_STATE entries.  Each shader stage has its own binding table,
29 * set by the 3DSTATE_BINDING_TABLE_POINTERS_* commands.  We stream out
30 * binding tables dynamically, storing them in special BOs we call "binders."
31 *
32 * Unfortunately, the hardware designers made 3DSTATE_BINDING_TABLE_POINTERS
33 * only accept a 16-bit pointer.  This means that all binding tables have to
34 * live within the 64kB range starting at Surface State Base Address.  (The
35 * actual SURFACE_STATE entries can live anywhere in the 4GB zone, as the
36 * binding table entries are full 32-bit pointers.)
37 *
38 * To handle this, we split a 4GB region of VMA into two memory zones.
39 * IRIS_MEMZONE_BINDER is a small region at the bottom able to hold a few
40 * binder BOs.  IRIS_MEMZONE_SURFACE contains the rest of the 4GB, and is
41 * always at a higher address than the binders.  This allows us to program
42 * Surface State Base Address to the binder BO's address, and offset the
43 * values in the binding table to account for the base not starting at the
44 * beginning of the 4GB region.
45 *
46 * This does mean that we have to emit STATE_BASE_ADDRESS and stall when
47 * we run out of space in the binder, which hopefully won't happen too often.
48 */
49
50#include <stdlib.h>
51#include "util/u_math.h"
52#include "iris_binder.h"
53#include "iris_bufmgr.h"
54#include "iris_context.h"
55
56#define BTP_ALIGNMENT 32
57
58/* Avoid using offset 0, tools consider it NULL */
59#define INIT_INSERT_POINT BTP_ALIGNMENT
60
61static bool
62binder_has_space(struct iris_binder *binder, unsigned size)
63{
64   return binder->insert_point + size <= IRIS_BINDER_SIZE;
65}
66
67static void
68binder_realloc(struct iris_context *ice)
69{
70   struct iris_screen *screen = (void *) ice->ctx.screen;
71   struct iris_bufmgr *bufmgr = screen->bufmgr;
72   struct iris_binder *binder = &ice->state.binder;
73
74   uint64_t next_address = IRIS_MEMZONE_BINDER_START;
75
76   if (binder->bo) {
77      /* Place the new binder just after the old binder, unless we've hit the
78       * end of the memory zone...then wrap around to the start again.
79       */
80      next_address = binder->bo->gtt_offset + IRIS_BINDER_SIZE;
81      if (next_address >= IRIS_MEMZONE_SURFACE_START)
82         next_address = IRIS_MEMZONE_BINDER_START;
83
84      iris_bo_unreference(binder->bo);
85   }
86
87
88   binder->bo =
89      iris_bo_alloc(bufmgr, "binder", IRIS_BINDER_SIZE, IRIS_MEMZONE_BINDER);
90   binder->bo->gtt_offset = next_address;
91   binder->map = iris_bo_map(NULL, binder->bo, MAP_WRITE);
92   binder->insert_point = INIT_INSERT_POINT;
93
94   /* Allocating a new binder requires changing Surface State Base Address,
95    * which also invalidates all our previous binding tables - each entry
96    * in those tables is an offset from the old base.
97    *
98    * We do this here so that iris_binder_reserve_3d correctly gets a new
99    * larger total_size when making the updated reservation.
100    */
101   ice->state.dirty |= IRIS_ALL_DIRTY_BINDINGS;
102}
103
104static uint32_t
105binder_insert(struct iris_binder *binder, unsigned size)
106{
107   uint32_t offset = binder->insert_point;
108
109   binder->insert_point = align(binder->insert_point + size, BTP_ALIGNMENT);
110
111   return offset;
112}
113
114/**
115 * Reserve a block of space in the binder, given the raw size in bytes.
116 */
117uint32_t
118iris_binder_reserve(struct iris_context *ice,
119                    unsigned size)
120{
121   struct iris_binder *binder = &ice->state.binder;
122
123   if (!binder_has_space(binder, size))
124      binder_realloc(ice);
125
126   assert(size > 0);
127   return binder_insert(binder, size);
128}
129
130/**
131 * Reserve and record binder space for 3D pipeline shader stages.
132 *
133 * Note that you must actually populate the new binding tables after
134 * calling this command - the new area is uninitialized.
135 */
136void
137iris_binder_reserve_3d(struct iris_context *ice)
138{
139   struct iris_compiled_shader **shaders = ice->shaders.prog;
140   struct iris_binder *binder = &ice->state.binder;
141   unsigned sizes[MESA_SHADER_STAGES] = {};
142   unsigned total_size;
143
144   /* If nothing is dirty, skip all this. */
145   if (!(ice->state.dirty & IRIS_ALL_DIRTY_BINDINGS))
146      return;
147
148   /* Get the binding table sizes for each stage */
149   for (int stage = 0; stage <= MESA_SHADER_FRAGMENT; stage++) {
150      if (!shaders[stage])
151         continue;
152
153      const struct brw_stage_prog_data *prog_data =
154         (const void *) shaders[stage]->prog_data;
155
156      /* Round up the size so our next table has an aligned starting offset */
157      sizes[stage] = align(prog_data->binding_table.size_bytes, BTP_ALIGNMENT);
158   }
159
160   /* Make space for the new binding tables...this may take two tries. */
161   while (true) {
162      total_size = 0;
163      for (int stage = 0; stage <= MESA_SHADER_FRAGMENT; stage++) {
164         if (ice->state.dirty & (IRIS_DIRTY_BINDINGS_VS << stage))
165            total_size += sizes[stage];
166      }
167
168      assert(total_size < IRIS_BINDER_SIZE);
169
170      if (total_size == 0)
171         return;
172
173      if (binder_has_space(binder, total_size))
174         break;
175
176      /* It didn't fit.  Allocate a new buffer and try again.  Note that
177       * this will flag all bindings dirty, which may increase total_size
178       * on the next iteration.
179       */
180      binder_realloc(ice);
181   }
182
183   /* Assign space and record the new binding table offsets. */
184   uint32_t offset = binder_insert(binder, total_size);
185
186   for (int stage = 0; stage <= MESA_SHADER_FRAGMENT; stage++) {
187      if (ice->state.dirty & (IRIS_DIRTY_BINDINGS_VS << stage)) {
188         binder->bt_offset[stage] = sizes[stage] > 0 ? offset : 0;
189         offset += sizes[stage];
190      }
191   }
192}
193
194void
195iris_binder_reserve_compute(struct iris_context *ice)
196{
197   if (!(ice->state.dirty & IRIS_DIRTY_BINDINGS_CS))
198      return;
199
200   struct iris_binder *binder = &ice->state.binder;
201   struct brw_stage_prog_data *prog_data =
202      ice->shaders.prog[MESA_SHADER_COMPUTE]->prog_data;
203
204   unsigned size = prog_data->binding_table.size_bytes;
205
206   if (size == 0)
207      return;
208
209   binder->bt_offset[MESA_SHADER_COMPUTE] = iris_binder_reserve(ice, size);
210}
211
212void
213iris_init_binder(struct iris_context *ice)
214{
215   memset(&ice->state.binder, 0, sizeof(struct iris_binder));
216   binder_realloc(ice);
217}
218
219void
220iris_destroy_binder(struct iris_binder *binder)
221{
222   iris_bo_unreference(binder->bo);
223}
224