src/gallium/drivers/iris/iris_binder.c

   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
  61 static bool
  62 binder_has_space(struct iris_binder *binder, unsigned size)
  63 {
  64    return binder->insert_point + size <= IRIS_BINDER_SIZE;
  65 }
  66
  67 static void
  68 binder_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
 104 static uint32_t
 105 binder_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  */
 117 uint32_t
 118 iris_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  */
 136 void
 137 iris_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
 194 void
 195 iris_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
 212 void
 213 iris_init_binder(struct iris_context *ice)
 214 {
 215    memset(&ice->state.binder, 0, sizeof(struct iris_binder));
 216    binder_realloc(ice);
 217 }
 218
 219 void
 220 iris_destroy_binder(struct iris_binder *binder)
 221 {
 222    iris_bo_unreference(binder->bo);
 223 }