From 0a7b252c5b0f5c5c0e114d913d6153bd2cc44ce9 Mon Sep 17 00:00:00 2001 From: Kenneth Graunke Date: Thu, 16 Feb 2017 20:05:39 -0800 Subject: [PATCH] i965: Enable ARB_transform_feedback2 on Sandybridge. The only feature over and above ES 3.0 is DrawTransformFeedback(). We already have to do the whole SOL_NUM_PRIMS_WRITTEN counter dance in order to compute the SVBI value for ResumeTransformFeedback(), at which point our existing GetTransformFeedbackVertexCount() implementation will do the trick (though with a stall to CPU map the buffer). Someday, we could probably implement DrawTransformFeedback() more efficiently, using the "Load Internal Vertex Count" feature of 3DSTATE_SVB_INDEX and the 3DPRIMITIVE indirect vertex count bit. Rumor has it this allows people to use WebGL 2.0 on Sandybridge. Note that we don't need pipelined register writes like Gen7+ because we use the 3DSTATE_SVB_INDEX command rather than MI_LOAD_REGISTER_MEM. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=99842 Signed-off-by: Kenneth Graunke Reviewed-by: Iago Toral Quiroga --- src/mesa/drivers/dri/i965/brw_context.c | 2 ++ src/mesa/drivers/dri/i965/intel_extensions.c | 3 +++ 2 files changed, 5 insertions(+) diff --git a/src/mesa/drivers/dri/i965/brw_context.c b/src/mesa/drivers/dri/i965/brw_context.c index 6a9f1570c31..de2f6948b25 100644 --- a/src/mesa/drivers/dri/i965/brw_context.c +++ b/src/mesa/drivers/dri/i965/brw_context.c @@ -483,6 +483,8 @@ brw_init_driver_functions(struct brw_context *brw, functions->EndTransformFeedback = brw_end_transform_feedback; functions->PauseTransformFeedback = brw_pause_transform_feedback; functions->ResumeTransformFeedback = brw_resume_transform_feedback; + functions->GetTransformFeedbackVertexCount = + brw_get_transform_feedback_vertex_count; } if (brw->gen >= 6) diff --git a/src/mesa/drivers/dri/i965/intel_extensions.c b/src/mesa/drivers/dri/i965/intel_extensions.c index f1290bf7b49..ec7ff02be84 100644 --- a/src/mesa/drivers/dri/i965/intel_extensions.c +++ b/src/mesa/drivers/dri/i965/intel_extensions.c @@ -158,6 +158,9 @@ intelInitExtensions(struct gl_context *ctx) ctx->Extensions.EXT_timer_query = true; } + if (brw->gen == 6) + ctx->Extensions.ARB_transform_feedback2 = true; + if (brw->gen >= 6) { ctx->Extensions.ARB_blend_func_extended = !driQueryOptionb(&brw->optionCache, "disable_blend_func_extended"); -- 2.30.2