[Mesa-dev] [PATCH v2 24/32] intel/isl: Add initial data-structure support for miptails

[Jason Ekstrand]

This commit just adds a miptail start field to isl_surf and wires it up
in the RENDER_SURFACE_STATE and 3DSTATE_DEPTH code.  We also add a
minimum miptail LOD so that client drivers have a knob to control the
miptails a bit.
---
 src/intel/isl/isl.c                    |  1 +
 src/intel/isl/isl.h                    | 11 +++++++++++
 src/intel/isl/isl_emit_depth_stencil.c |  2 +-
 src/intel/isl/isl_surface_state.c      |  5 +----
 4 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/src/intel/isl/isl.c b/src/intel/isl/isl.c
index 3d0741bc207..4a8380ad540 100644
--- a/src/intel/isl/isl.c
+++ b/src/intel/isl/isl.c
@@ -1653,6 +1653,7 @@ isl_surf_init_s(const struct isl_device *dev,
       .row_pitch_B = row_pitch_B,
       .array_pitch_el_rows = array_pitch_el_rows,
       .array_pitch_span = array_pitch_span,
+      .miptail_start_level = 15,
 
       .usage = info->usage,
    };
diff --git a/src/intel/isl/isl.h b/src/intel/isl/isl.h
index 213f5b408e2..4fb212e33d5 100644
--- a/src/intel/isl/isl.h
+++ b/src/intel/isl/isl.h
@@ -1145,6 +1145,9 @@ struct isl_surf_init_info {
    /** Lower bound for isl_surf::alignment, in bytes. */
    uint32_t min_alignment_B;
 
+   /** Lower bound for where to start the miptail */
+   uint32_t min_miptail_start_level;
+
    /**
     * Exact value for isl_surf::row_pitch. Ignored if zero.  isl_surf_init()
     * will fail if this is misaligned or out of bounds.
@@ -1219,6 +1222,14 @@ struct isl_surf {
 
    enum isl_array_pitch_span array_pitch_span;
 
+   /**
+    * Level at which the miptail starts.
+    *
+    * This value is inclusive in the sense that the miptail contains this
+    * level.
+    */
+   uint32_t miptail_start_level;
+
    /** Copy of isl_surf_init_info::usage. */
    isl_surf_usage_flags_t usage;
 };
diff --git a/src/intel/isl/isl_emit_depth_stencil.c b/src/intel/isl/isl_emit_depth_stencil.c
index b07da781be8..c1a40ee20f0 100644
--- a/src/intel/isl/isl_emit_depth_stencil.c
+++ b/src/intel/isl/isl_emit_depth_stencil.c
@@ -115,7 +115,7 @@ isl_genX(emit_depth_stencil_hiz_s)(const struct isl_device *dev, void *batch,
       /* We don't use miptails yet.  The PRM recommends that you set "Mip Tail
        * Start LOD" to 15 to prevent the hardware from trying to use them.
        */
-      db.MipTailStartLOD = 15;
+      db.MipTailStartLOD = info->depth_surf->miptail_start_level;
 #elif GEN_GEN >= 7
       /* Gen7+ depth is always Y-tiled.  We don't even have a bit for it */
 #else
diff --git a/src/intel/isl/isl_surface_state.c b/src/intel/isl/isl_surface_state.c
index abd4767acd7..b3e51d6f5e0 100644
--- a/src/intel/isl/isl_surface_state.c
+++ b/src/intel/isl/isl_surface_state.c
@@ -423,10 +423,7 @@ isl_genX(surf_fill_state_s)(const struct isl_device *dev, void *state,
    }
 
 #if GEN_GEN >= 9
-   /* We don't use miptails yet.  The PRM recommends that you set "Mip Tail
-    * Start LOD" to 15 to prevent the hardware from trying to use them.
-    */
-   s.MipTailStartLOD = 15;
+   s.MipTailStartLOD = info->surf->miptail_start_level;
 #endif
 
 #if GEN_GEN >= 6
-- 
2.19.1