* Code to initialize the binding table entries used by transform feedback.
*/
+#include "main/bufferobj.h"
+#include "main/macros.h"
#include "brw_context.h"
#include "intel_batchbuffer.h"
#include "brw_defines.h"
+#include "brw_state.h"
+#include "main/transformfeedback.h"
static void
gen6_update_sol_surfaces(struct brw_context *brw)
{
- struct gl_context *ctx = &brw->intel.ctx;
- /* _NEW_TRANSFORM_FEEDBACK */
- struct gl_transform_feedback_object *xfb_obj =
- ctx->TransformFeedback.CurrentObject;
- /* BRW_NEW_VERTEX_PROGRAM */
- const struct gl_shader_program *shaderprog =
- ctx->Shader.CurrentVertexProgram;
- const struct gl_transform_feedback_info *linked_xfb_info =
- &shaderprog->LinkedTransformFeedback;
- int i;
-
- for (i = 0; i < BRW_MAX_SOL_BINDINGS; ++i) {
- const int surf_index = SURF_INDEX_SOL_BINDING(i);
- if (xfb_obj->Active && i < linked_xfb_info->NumOutputs) {
+ struct gl_context *ctx = &brw->ctx;
+ bool xfb_active = _mesa_is_xfb_active_and_unpaused(ctx);
+ struct gl_transform_feedback_object *xfb_obj;
+ const struct gl_transform_feedback_info *linked_xfb_info = NULL;
+
+ if (xfb_active) {
+ /* BRW_NEW_TRANSFORM_FEEDBACK */
+ xfb_obj = ctx->TransformFeedback.CurrentObject;
+ linked_xfb_info = xfb_obj->program->sh.LinkedTransformFeedback;
+ }
+
+ for (int i = 0; i < BRW_MAX_SOL_BINDINGS; ++i) {
+ const int surf_index = BRW_GEN6_SOL_BINDING_START + i;
+ if (xfb_active && i < linked_xfb_info->NumOutputs) {
unsigned buffer = linked_xfb_info->Outputs[i].OutputBuffer;
unsigned buffer_offset =
xfb_obj->Offset[buffer] / 4 +
linked_xfb_info->Outputs[i].DstOffset;
- brw_update_sol_surface(
- brw, xfb_obj->Buffers[buffer], &brw->bind.surf_offset[surf_index],
- linked_xfb_info->Outputs[i].NumComponents,
- linked_xfb_info->BufferStride[buffer], buffer_offset);
+ if (brw->programs[MESA_SHADER_GEOMETRY]) {
+ brw_update_sol_surface(
+ brw, xfb_obj->Buffers[buffer],
+ &brw->gs.base.surf_offset[surf_index],
+ linked_xfb_info->Outputs[i].NumComponents,
+ linked_xfb_info->Buffers[buffer].Stride, buffer_offset);
+ } else {
+ brw_update_sol_surface(
+ brw, xfb_obj->Buffers[buffer],
+ &brw->ff_gs.surf_offset[surf_index],
+ linked_xfb_info->Outputs[i].NumComponents,
+ linked_xfb_info->Buffers[buffer].Stride, buffer_offset);
+ }
} else {
- brw->bind.surf_offset[surf_index] = 0;
+ if (!brw->programs[MESA_SHADER_GEOMETRY])
+ brw->ff_gs.surf_offset[surf_index] = 0;
+ else
+ brw->gs.base.surf_offset[surf_index] = 0;
}
}
+
+ brw->ctx.NewDriverState |= BRW_NEW_SURFACES;
}
const struct brw_tracked_state gen6_sol_surface = {
.dirty = {
- .mesa = _NEW_TRANSFORM_FEEDBACK,
- .brw = (BRW_NEW_BATCH |
- BRW_NEW_VERTEX_PROGRAM),
- .cache = 0
+ .mesa = 0,
+ .brw = BRW_NEW_BATCH |
+ BRW_NEW_BLORP |
+ BRW_NEW_TRANSFORM_FEEDBACK,
},
.emit = gen6_update_sol_surfaces,
};
+/**
+ * Constructs the binding table for the WM surface state, which maps unit
+ * numbers to surface state objects.
+ */
+static void
+brw_gs_upload_binding_table(struct brw_context *brw)
+{
+ uint32_t *bind;
+ struct gl_context *ctx = &brw->ctx;
+ const struct gl_program *prog;
+ bool need_binding_table = false;
+
+ /* We have two scenarios here:
+ * 1) We are using a geometry shader only to implement transform feedback
+ * for a vertex shader (brw->programs[MESA_SHADER_GEOMETRY] == NULL).
+ * In this case, we only need surfaces for transform feedback in the
+ * GS stage.
+ * 2) We have a user-provided geometry shader. In this case we may need
+ * surfaces for transform feedback and/or other stuff, like textures,
+ * in the GS stage.
+ */
+
+ if (!brw->programs[MESA_SHADER_GEOMETRY]) {
+ /* BRW_NEW_VERTEX_PROGRAM */
+ prog = ctx->_Shader->CurrentProgram[MESA_SHADER_VERTEX];
+ if (prog) {
+ /* Skip making a binding table if we don't have anything to put in it */
+ const struct gl_transform_feedback_info *linked_xfb_info =
+ prog->sh.LinkedTransformFeedback;
+ need_binding_table = linked_xfb_info->NumOutputs > 0;
+ }
+ if (!need_binding_table) {
+ if (brw->ff_gs.bind_bo_offset != 0) {
+ brw->ctx.NewDriverState |= BRW_NEW_BINDING_TABLE_POINTERS;
+ brw->ff_gs.bind_bo_offset = 0;
+ }
+ return;
+ }
+
+ /* Might want to calculate nr_surfaces first, to avoid taking up so much
+ * space for the binding table. Anyway, in this case we know that we only
+ * use BRW_MAX_SOL_BINDINGS surfaces at most.
+ */
+ bind = brw_state_batch(brw, sizeof(uint32_t) * BRW_MAX_SOL_BINDINGS,
+ 32, &brw->ff_gs.bind_bo_offset);
+
+ /* BRW_NEW_SURFACES */
+ memcpy(bind, brw->ff_gs.surf_offset,
+ BRW_MAX_SOL_BINDINGS * sizeof(uint32_t));
+ } else {
+ /* BRW_NEW_GEOMETRY_PROGRAM */
+ prog = ctx->_Shader->CurrentProgram[MESA_SHADER_GEOMETRY];
+ if (prog) {
+ /* Skip making a binding table if we don't have anything to put in it */
+ struct brw_stage_prog_data *prog_data = brw->gs.base.prog_data;
+ const struct gl_transform_feedback_info *linked_xfb_info =
+ prog->sh.LinkedTransformFeedback;
+ need_binding_table = linked_xfb_info->NumOutputs > 0 ||
+ prog_data->binding_table.size_bytes > 0;
+ }
+ if (!need_binding_table) {
+ if (brw->gs.base.bind_bo_offset != 0) {
+ brw->gs.base.bind_bo_offset = 0;
+ brw->ctx.NewDriverState |= BRW_NEW_BINDING_TABLE_POINTERS;
+ }
+ return;
+ }
+
+ /* Might want to calculate nr_surfaces first, to avoid taking up so much
+ * space for the binding table.
+ */
+ bind = brw_state_batch(brw, sizeof(uint32_t) * BRW_MAX_SURFACES,
+ 32, &brw->gs.base.bind_bo_offset);
+
+ /* BRW_NEW_SURFACES */
+ memcpy(bind, brw->gs.base.surf_offset,
+ BRW_MAX_SURFACES * sizeof(uint32_t));
+ }
+
+ brw->ctx.NewDriverState |= BRW_NEW_BINDING_TABLE_POINTERS;
+}
+
+const struct brw_tracked_state gen6_gs_binding_table = {
+ .dirty = {
+ .mesa = 0,
+ .brw = BRW_NEW_BATCH |
+ BRW_NEW_BLORP |
+ BRW_NEW_GEOMETRY_PROGRAM |
+ BRW_NEW_VERTEX_PROGRAM |
+ BRW_NEW_SURFACES,
+ },
+ .emit = brw_gs_upload_binding_table,
+};
+
+struct gl_transform_feedback_object *
+brw_new_transform_feedback(struct gl_context *ctx, GLuint name)
+{
+ struct brw_context *brw = brw_context(ctx);
+ struct brw_transform_feedback_object *brw_obj =
+ CALLOC_STRUCT(brw_transform_feedback_object);
+ if (!brw_obj)
+ return NULL;
+
+ _mesa_init_transform_feedback_object(&brw_obj->base, name);
+
+ brw_obj->offset_bo =
+ brw_bo_alloc(brw->bufmgr, "transform feedback offsets", 16,
+ BRW_MEMZONE_OTHER);
+ brw_obj->prim_count_bo =
+ brw_bo_alloc(brw->bufmgr, "xfb primitive counts", 16384,
+ BRW_MEMZONE_OTHER);
+
+ return &brw_obj->base;
+}
+
+void
+brw_delete_transform_feedback(struct gl_context *ctx,
+ struct gl_transform_feedback_object *obj)
+{
+ struct brw_transform_feedback_object *brw_obj =
+ (struct brw_transform_feedback_object *) obj;
+
+ brw_bo_unreference(brw_obj->offset_bo);
+ brw_bo_unreference(brw_obj->prim_count_bo);
+
+ _mesa_delete_transform_feedback_object(ctx, obj);
+}
+
+/**
+ * Tally the number of primitives generated so far.
+ *
+ * The buffer contains a series of pairs:
+ * (<start0, start1, start2, start3>, <end0, end1, end2, end3>) ;
+ * (<start0, start1, start2, start3>, <end0, end1, end2, end3>) ;
+ *
+ * For each stream, we subtract the pair of values (end - start) to get the
+ * number of primitives generated during one section. We accumulate these
+ * values, adding them up to get the total number of primitives generated.
+ *
+ * Note that we expose one stream pre-Gen7, so the above is just (start, end).
+ */
+static void
+aggregate_transform_feedback_counter(
+ struct brw_context *brw,
+ struct brw_bo *bo,
+ struct brw_transform_feedback_counter *counter)
+{
+ const unsigned streams = brw->ctx.Const.MaxVertexStreams;
+
+ /* If the current batch is still contributing to the number of primitives
+ * generated, flush it now so the results will be present when mapped.
+ */
+ if (brw_batch_references(&brw->batch, bo))
+ intel_batchbuffer_flush(brw);
+
+ if (unlikely(brw->perf_debug && brw_bo_busy(bo)))
+ perf_debug("Stalling for # of transform feedback primitives written.\n");
+
+ uint64_t *prim_counts = brw_bo_map(brw, bo, MAP_READ);
+ prim_counts += counter->bo_start * streams;
+
+ for (unsigned i = counter->bo_start; i + 1 < counter->bo_end; i += 2) {
+ for (unsigned s = 0; s < streams; s++)
+ counter->accum[s] += prim_counts[streams + s] - prim_counts[s];
+
+ prim_counts += 2 * streams;
+ }
+
+ brw_bo_unmap(bo);
+
+ /* We've already gathered up the old data; we can safely overwrite it now. */
+ counter->bo_start = counter->bo_end = 0;
+}
+
+/**
+ * Store the SO_NUM_PRIMS_WRITTEN counters for each stream (4 uint64_t values)
+ * to prim_count_bo.
+ *
+ * If prim_count_bo is out of space, gather up the results so far into
+ * prims_generated[] and allocate a new buffer with enough space.
+ *
+ * The number of primitives written is used to compute the number of vertices
+ * written to a transform feedback stream, which is required to implement
+ * DrawTransformFeedback().
+ */
+void
+brw_save_primitives_written_counters(struct brw_context *brw,
+ struct brw_transform_feedback_object *obj)
+{
+ const struct gen_device_info *devinfo = &brw->screen->devinfo;
+ const struct gl_context *ctx = &brw->ctx;
+ const int streams = ctx->Const.MaxVertexStreams;
+
+ assert(obj->prim_count_bo != NULL);
+
+ /* Check if there's enough space for a new pair of four values. */
+ if ((obj->counter.bo_end + 2) * streams * sizeof(uint64_t) >=
+ obj->prim_count_bo->size) {
+ aggregate_transform_feedback_counter(brw, obj->prim_count_bo,
+ &obj->previous_counter);
+ aggregate_transform_feedback_counter(brw, obj->prim_count_bo,
+ &obj->counter);
+ }
+
+ /* Flush any drawing so that the counters have the right values. */
+ brw_emit_mi_flush(brw);
+
+ /* Emit MI_STORE_REGISTER_MEM commands to write the values. */
+ if (devinfo->gen >= 7) {
+ for (int i = 0; i < streams; i++) {
+ int offset = (streams * obj->counter.bo_end + i) * sizeof(uint64_t);
+ brw_store_register_mem64(brw, obj->prim_count_bo,
+ GEN7_SO_NUM_PRIMS_WRITTEN(i),
+ offset);
+ }
+ } else {
+ brw_store_register_mem64(brw, obj->prim_count_bo,
+ GEN6_SO_NUM_PRIMS_WRITTEN,
+ obj->counter.bo_end * sizeof(uint64_t));
+ }
+
+ /* Update where to write data to. */
+ obj->counter.bo_end++;
+}
+
+static void
+compute_vertices_written_so_far(struct brw_context *brw,
+ struct brw_transform_feedback_object *obj,
+ struct brw_transform_feedback_counter *counter,
+ uint64_t *vertices_written)
+{
+ const struct gl_context *ctx = &brw->ctx;
+ unsigned vertices_per_prim = 0;
+
+ switch (obj->primitive_mode) {
+ case GL_POINTS:
+ vertices_per_prim = 1;
+ break;
+ case GL_LINES:
+ vertices_per_prim = 2;
+ break;
+ case GL_TRIANGLES:
+ vertices_per_prim = 3;
+ break;
+ default:
+ unreachable("Invalid transform feedback primitive mode.");
+ }
+
+ /* Get the number of primitives generated. */
+ aggregate_transform_feedback_counter(brw, obj->prim_count_bo, counter);
+
+ for (int i = 0; i < ctx->Const.MaxVertexStreams; i++) {
+ vertices_written[i] = vertices_per_prim * counter->accum[i];
+ }
+}
+
+/**
+ * Compute the number of vertices written by the last transform feedback
+ * begin/end block.
+ */
+static void
+compute_xfb_vertices_written(struct brw_context *brw,
+ struct brw_transform_feedback_object *obj)
+{
+ if (obj->vertices_written_valid || !obj->base.EndedAnytime)
+ return;
+
+ compute_vertices_written_so_far(brw, obj, &obj->previous_counter,
+ obj->vertices_written);
+ obj->vertices_written_valid = true;
+}
+
+/**
+ * GetTransformFeedbackVertexCount() driver hook.
+ *
+ * Returns the number of vertices written to a particular stream by the last
+ * Begin/EndTransformFeedback block. Used to implement DrawTransformFeedback().
+ */
+GLsizei
+brw_get_transform_feedback_vertex_count(struct gl_context *ctx,
+ struct gl_transform_feedback_object *obj,
+ GLuint stream)
+{
+ struct brw_context *brw = brw_context(ctx);
+ struct brw_transform_feedback_object *brw_obj =
+ (struct brw_transform_feedback_object *) obj;
+
+ assert(obj->EndedAnytime);
+ assert(stream < ctx->Const.MaxVertexStreams);
+
+ compute_xfb_vertices_written(brw, brw_obj);
+ return brw_obj->vertices_written[stream];
+}
+
+void
+brw_begin_transform_feedback(struct gl_context *ctx, GLenum mode,
+ struct gl_transform_feedback_object *obj)
+{
+ struct brw_context *brw = brw_context(ctx);
+ const struct gl_program *prog;
+ const struct gl_transform_feedback_info *linked_xfb_info;
+ struct gl_transform_feedback_object *xfb_obj =
+ ctx->TransformFeedback.CurrentObject;
+ struct brw_transform_feedback_object *brw_obj =
+ (struct brw_transform_feedback_object *) xfb_obj;
+
+ assert(brw->screen->devinfo.gen == 6);
+
+ if (ctx->_Shader->CurrentProgram[MESA_SHADER_GEOMETRY]) {
+ /* BRW_NEW_GEOMETRY_PROGRAM */
+ prog = ctx->_Shader->CurrentProgram[MESA_SHADER_GEOMETRY];
+ } else {
+ /* BRW_NEW_VERTEX_PROGRAM */
+ prog = ctx->_Shader->CurrentProgram[MESA_SHADER_VERTEX];
+ }
+ linked_xfb_info = prog->sh.LinkedTransformFeedback;
+
+ /* Compute the maximum number of vertices that we can write without
+ * overflowing any of the buffers currently being used for feedback.
+ */
+ brw_obj->max_index
+ = _mesa_compute_max_transform_feedback_vertices(ctx, xfb_obj,
+ linked_xfb_info);
+
+ /* Initialize the SVBI 0 register to zero and set the maximum index. */
+ BEGIN_BATCH(4);
+ OUT_BATCH(_3DSTATE_GS_SVB_INDEX << 16 | (4 - 2));
+ OUT_BATCH(0); /* SVBI 0 */
+ OUT_BATCH(0); /* starting index */
+ OUT_BATCH(brw_obj->max_index);
+ ADVANCE_BATCH();
+
+ /* Initialize the rest of the unused streams to sane values. Otherwise,
+ * they may indicate that there is no room to write data and prevent
+ * anything from happening at all.
+ */
+ for (int i = 1; i < 4; i++) {
+ BEGIN_BATCH(4);
+ OUT_BATCH(_3DSTATE_GS_SVB_INDEX << 16 | (4 - 2));
+ OUT_BATCH(i << SVB_INDEX_SHIFT);
+ OUT_BATCH(0); /* starting index */
+ OUT_BATCH(0xffffffff);
+ ADVANCE_BATCH();
+ }
+
+ /* Store the starting value of the SO_NUM_PRIMS_WRITTEN counters. */
+ brw_save_primitives_written_counters(brw, brw_obj);
+
+ brw_obj->primitive_mode = mode;
+}
+
void
brw_end_transform_feedback(struct gl_context *ctx,
struct gl_transform_feedback_object *obj)
{
- /* After EndTransformFeedback, it's likely that the client program will try
- * to draw using the contents of the transform feedback buffer as vertex
- * input. In order for this to work, we need to flush the data through at
- * least the GS stage of the pipeline, and flush out the render cache. For
- * simplicity, just do a full flush.
+ struct brw_context *brw = brw_context(ctx);
+ struct brw_transform_feedback_object *brw_obj =
+ (struct brw_transform_feedback_object *) obj;
+
+ /* Store the ending value of the SO_NUM_PRIMS_WRITTEN counters. */
+ if (!obj->Paused)
+ brw_save_primitives_written_counters(brw, brw_obj);
+
+ /* We've reached the end of a transform feedback begin/end block. This
+ * means that future DrawTransformFeedback() calls will need to pick up the
+ * results of the current counter, and that it's time to roll back the
+ * current primitive counter to zero.
+ */
+ brw_obj->previous_counter = brw_obj->counter;
+ brw_reset_transform_feedback_counter(&brw_obj->counter);
+
+ /* EndTransformFeedback() means that we need to update the number of
+ * vertices written. Since it's only necessary if DrawTransformFeedback()
+ * is called and it means mapping a buffer object, we delay computing it
+ * until it's absolutely necessary to try and avoid stalls.
+ */
+ brw_obj->vertices_written_valid = false;
+}
+
+void
+brw_pause_transform_feedback(struct gl_context *ctx,
+ struct gl_transform_feedback_object *obj)
+{
+ struct brw_context *brw = brw_context(ctx);
+ struct brw_transform_feedback_object *brw_obj =
+ (struct brw_transform_feedback_object *) obj;
+
+ /* Store the temporary ending value of the SO_NUM_PRIMS_WRITTEN counters.
+ * While this operation is paused, other transform feedback actions may
+ * occur, which will contribute to the counters. We need to exclude that
+ * from our counts.
*/
+ brw_save_primitives_written_counters(brw, brw_obj);
+}
+
+void
+brw_resume_transform_feedback(struct gl_context *ctx,
+ struct gl_transform_feedback_object *obj)
+{
struct brw_context *brw = brw_context(ctx);
- struct intel_context *intel = &brw->intel;
- intel_batchbuffer_emit_mi_flush(intel);
+ struct brw_transform_feedback_object *brw_obj =
+ (struct brw_transform_feedback_object *) obj;
+
+ /* Reload SVBI 0 with the count of vertices written so far. */
+ uint64_t svbi;
+ compute_vertices_written_so_far(brw, brw_obj, &brw_obj->counter, &svbi);
+
+ BEGIN_BATCH(4);
+ OUT_BATCH(_3DSTATE_GS_SVB_INDEX << 16 | (4 - 2));
+ OUT_BATCH(0); /* SVBI 0 */
+ OUT_BATCH((uint32_t) svbi); /* starting index */
+ OUT_BATCH(brw_obj->max_index);
+ ADVANCE_BATCH();
+
+ /* Initialize the rest of the unused streams to sane values. Otherwise,
+ * they may indicate that there is no room to write data and prevent
+ * anything from happening at all.
+ */
+ for (int i = 1; i < 4; i++) {
+ BEGIN_BATCH(4);
+ OUT_BATCH(_3DSTATE_GS_SVB_INDEX << 16 | (4 - 2));
+ OUT_BATCH(i << SVB_INDEX_SHIFT);
+ OUT_BATCH(0); /* starting index */
+ OUT_BATCH(0xffffffff);
+ ADVANCE_BATCH();
+ }
+
+ /* Store the new starting value of the SO_NUM_PRIMS_WRITTEN counters. */
+ brw_save_primitives_written_counters(brw, brw_obj);
}