[Mesa-dev] [PATCH 12/14] i965: Define tracked state for separate stencil buffer

[chad at chad-versace.us]

From: Chad Versace <chad.versace at intel.com>

- Add field brw_context.state.stencil_region.
- Define dirty bit BRW_NEW_STENCIL_BUFFER, which signals that
  brw_context.state.stencil_region has changed.
- Define 'struct brw_tracked_state brw_stencil_buffer' and add it to
  gen4_atoms.

Signed-off-by: Chad Versace <chad.versace at intel.com>
---
 src/mesa/drivers/dri/i965/brw_context.h      |    5 +++
 src/mesa/drivers/dri/i965/brw_misc_state.c   |   45 ++++++++++++++++++++++++++
 src/mesa/drivers/dri/i965/brw_state.h        |    1 +
 src/mesa/drivers/dri/i965/brw_state_upload.c |    2 +
 src/mesa/drivers/dri/i965/brw_vtbl.c         |    1 +
 5 files changed, 54 insertions(+), 0 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_context.h b/src/mesa/drivers/dri/i965/brw_context.h
index 26cd820..4e1cb0b 100644
--- a/src/mesa/drivers/dri/i965/brw_context.h
+++ b/src/mesa/drivers/dri/i965/brw_context.h
@@ -146,6 +146,8 @@ struct brw_context;
 #define BRW_NEW_INDEX_BUFFER		0x100000
 #define BRW_NEW_VS_CONSTBUF		0x200000
 #define BRW_NEW_WM_CONSTBUF		0x400000
+/** \see brw_context.state.stencil_region */
+#define BRW_NEW_STENCIL_BUFFER		0x800000
 
 struct brw_state_flags {
    /** State update flags signalled by mesa internals */
@@ -482,6 +484,9 @@ struct brw_context
       /** \see struct brw_tracked_state brw_depthbuffer */
       struct intel_region *depth_region;
 
+      /** \see struct brw_tracked_state brw_stencil_buffer */
+      struct intel_region *stencil_region;
+
       /** \} */
 
       /**
diff --git a/src/mesa/drivers/dri/i965/brw_misc_state.c b/src/mesa/drivers/dri/i965/brw_misc_state.c
index 874a1d5..972d6c5 100644
--- a/src/mesa/drivers/dri/i965/brw_misc_state.c
+++ b/src/mesa/drivers/dri/i965/brw_misc_state.c
@@ -326,7 +326,52 @@ const struct brw_tracked_state brw_depthbuffer = {
    .emit = emit_depthbuffer,
 };
 
+static void prepare_stencil_buffer(struct brw_context *brw)
+{
+   struct intel_region *region = brw->state.stencil_region;
+
+   if (region != NULL) {
+      /* Separate stencil can only be used when HiZ is enabled. */
+      assert(intel_framebuffer_has_hiz(brw->intel.ctx.DrawBuffer));
+
+      brw_add_validated_bo(brw, region->buffer);
+   }
+}
+
+static void emit_stencil_buffer(struct brw_context *brw)
+{
+   struct intel_context *intel = &brw->intel;
+   struct intel_region *region = brw->state.stencil_region;
+   uint32_t length = 3;
+   uint32_t bias = 2;
+
+   if (region == NULL)
+      return;
+
+   /* Separate stencil can only be used when HiZ is enabled. */
+   assert(intel_framebuffer_has_hiz(brw->intel.ctx.DrawBuffer));
 
+   BEGIN_BATCH(length);
+   OUT_BATCH((_3DSTATE_STENCIL_BUFFER << 16) | (length - bias));
+   OUT_BATCH(region->pitch * region->cpp - 1);
+   OUT_RELOC(region->buffer,
+             I915_GEM_DOMAIN_RENDER, I915_GEM_DOMAIN_RENDER,
+             0);
+   ADVANCE_BATCH();
+}
+
+/**
+ * \see brw_context.state.stencil_region
+ */
+const struct brw_tracked_state brw_stencil_buffer = {
+   .dirty = {
+      .mesa = 0,
+      .brw = BRW_NEW_STENCIL_BUFFER | BRW_NEW_BATCH,
+      .cache = 0,
+   },
+   .prepare = prepare_stencil_buffer,
+   .emit = emit_stencil_buffer,
+};
 
 /***********************************************************************
  * Polygon stipple packet
diff --git a/src/mesa/drivers/dri/i965/brw_state.h b/src/mesa/drivers/dri/i965/brw_state.h
index 8b9e3a4..55e65a4 100644
--- a/src/mesa/drivers/dri/i965/brw_state.h
+++ b/src/mesa/drivers/dri/i965/brw_state.h
@@ -72,6 +72,7 @@ extern const struct brw_tracked_state brw_sf_prog;
 extern const struct brw_tracked_state brw_sf_unit;
 extern const struct brw_tracked_state brw_sf_vp;
 extern const struct brw_tracked_state brw_state_base_address;
+extern const struct brw_tracked_state brw_stencil_buffer;
 extern const struct brw_tracked_state brw_urb_fence;
 extern const struct brw_tracked_state brw_vertex_state;
 extern const struct brw_tracked_state brw_vs_surfaces;
diff --git a/src/mesa/drivers/dri/i965/brw_state_upload.c b/src/mesa/drivers/dri/i965/brw_state_upload.c
index 008aceb..bc24f75 100644
--- a/src/mesa/drivers/dri/i965/brw_state_upload.c
+++ b/src/mesa/drivers/dri/i965/brw_state_upload.c
@@ -88,6 +88,7 @@ static const struct brw_tracked_state *gen4_atoms[] =
    &brw_blend_constant_color,
 
    &brw_depthbuffer,
+   &brw_stencil_buffer,
 
    &brw_polygon_stipple,
    &brw_polygon_stipple_offset,
@@ -309,6 +310,7 @@ static struct dirty_bit_map brw_bits[] = {
    DEFINE_BIT(BRW_NEW_NR_VS_SURFACES),
    DEFINE_BIT(BRW_NEW_VS_CONSTBUF),
    DEFINE_BIT(BRW_NEW_WM_CONSTBUF),
+   DEFINE_BIT(BRW_NEW_STENCIL_BUFFER),
    {0, 0, 0}
 };
 
diff --git a/src/mesa/drivers/dri/i965/brw_vtbl.c b/src/mesa/drivers/dri/i965/brw_vtbl.c
index 4939e97..fc98c92 100644
--- a/src/mesa/drivers/dri/i965/brw_vtbl.c
+++ b/src/mesa/drivers/dri/i965/brw_vtbl.c
@@ -73,6 +73,7 @@ static void brw_destroy_context( struct intel_context *intel )
    }
 
    intel_region_release(&brw->state.depth_region);
+   intel_region_release(&brw->state.stencil_region);
 
    dri_bo_release(&brw->curbe.curbe_bo);
    dri_bo_release(&brw->vs.prog_bo);
-- 
1.7.5