i965: Make sure constants re-sent after constant buffer reallocation.

The hardware requires that after constant buffers for a stage are
allocated using a 3DSTATE_PUSH_CONSTANT_ALLOC_{VS,HS,DS,GS,PS}
command, and prior to execution of a 3DPRIMITIVE, the corresponding
stage's constant buffers must be reprogrammed using a
3DSTATE_CONSTANT_{VS,HS,DS,GS,PS} command.

Previously we didn't need to worry about this, because we only
programmed 3DSTATE_PUSH_CONSTANT_ALLOC_{VS,HS,DS,GS,PS} once on
startup (or, previous to that, whenever BRW_NEW_CONTEXT was flagged).
But now that we reallocate the constant buffers whenever geometry
shaders are switched on and off, we need to make sure the constant
buffers are reprogrammed.

We do this by adding a new bit, BRW_NEW_PUSH_CONSTANT_ALLOCATION, to
brw->state.dirty.brw.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>

src/mesa/drivers/dri/i965/brw_context.h

@@ -158,6 +158,7 @@ enum brw_state_id {
    BRW_STATE_UNIFORM_BUFFER,
    BRW_STATE_META_IN_PROGRESS,
    BRW_STATE_INTERPOLATION_MAP,
+   BRW_STATE_PUSH_CONSTANT_ALLOCATION,
    BRW_NUM_STATE_BITS
 };
 
@@ -194,6 +195,7 @@ enum brw_state_id {
 #define BRW_NEW_UNIFORM_BUFFER          (1 << BRW_STATE_UNIFORM_BUFFER)
 #define BRW_NEW_META_IN_PROGRESS        (1 << BRW_STATE_META_IN_PROGRESS)
 #define BRW_NEW_INTERPOLATION_MAP       (1 << BRW_STATE_INTERPOLATION_MAP)
+#define BRW_NEW_PUSH_CONSTANT_ALLOCATION (1 << BRW_STATE_PUSH_CONSTANT_ALLOCATION)
 
 struct brw_state_flags {
    /** State update flags signalled by mesa internals */

src/mesa/drivers/dri/i965/gen6_gs_state.c

@@ -81,7 +81,7 @@ upload_gs_state(struct brw_context *brw)
 const struct brw_tracked_state gen6_gs_state = {
    .dirty = {
       .mesa  = _NEW_TRANSFORM,
-      .brw   = BRW_NEW_CONTEXT,
+      .brw   = BRW_NEW_CONTEXT | BRW_NEW_PUSH_CONSTANT_ALLOCATION,
       .cache = CACHE_NEW_FF_GS_PROG
    },
    .emit = upload_gs_state,

src/mesa/drivers/dri/i965/gen6_vs_state.c

@@ -206,7 +206,8 @@ const struct brw_tracked_state gen6_vs_state = {
       .mesa  = _NEW_TRANSFORM | _NEW_PROGRAM_CONSTANTS,
       .brw   = (BRW_NEW_CONTEXT |
 		BRW_NEW_VERTEX_PROGRAM |
-		BRW_NEW_BATCH),
+		BRW_NEW_BATCH |
+                BRW_NEW_PUSH_CONSTANT_ALLOCATION),
       .cache = CACHE_NEW_VS_PROG | CACHE_NEW_SAMPLER
    },
    .emit = upload_vs_state,

src/mesa/drivers/dri/i965/gen6_wm_state.c

@@ -229,7 +229,8 @@ const struct brw_tracked_state gen6_wm_state = {
 		_NEW_POLYGON |
                 _NEW_MULTISAMPLE),
       .brw   = (BRW_NEW_FRAGMENT_PROGRAM |
-		BRW_NEW_BATCH),
+		BRW_NEW_BATCH |
+                BRW_NEW_PUSH_CONSTANT_ALLOCATION),
       .cache = (CACHE_NEW_SAMPLER |
 		CACHE_NEW_WM_PROG)
    },

src/mesa/drivers/dri/i965/gen7_urb.c

@@ -81,6 +81,19 @@ gen7_allocate_push_constants(struct brw_context *brw)
 
    gen7_emit_push_constant_state(brw, multiplier * vs_size,
                                  multiplier * gs_size, multiplier * fs_size);
+
+   /* From p115 of the Ivy Bridge PRM (3.2.1.4 3DSTATE_PUSH_CONSTANT_ALLOC_VS):
+    *
+    *     Programming Restriction:
+    *
+    *     The 3DSTATE_CONSTANT_VS must be reprogrammed prior to the next
+    *     3DPRIMITIVE command after programming the
+    *     3DSTATE_PUSH_CONSTANT_ALLOC_VS.
+    *
+    * Similar text exists for the other 3DSTATE_PUSH_CONSTANT_ALLOC_*
+    * commands.
+    */
+   brw->state.dirty.brw |= BRW_NEW_PUSH_CONSTANT_ALLOCATION;
 }
 
 void

src/mesa/drivers/dri/i965/gen7_vs_state.c

@@ -116,7 +116,8 @@ const struct brw_tracked_state gen7_vs_state = {
       .brw   = (BRW_NEW_CONTEXT |
 		BRW_NEW_VERTEX_PROGRAM |
 		BRW_NEW_VS_BINDING_TABLE |
-		BRW_NEW_BATCH),
+		BRW_NEW_BATCH |
+                BRW_NEW_PUSH_CONSTANT_ALLOCATION),
       .cache = CACHE_NEW_VS_PROG | CACHE_NEW_SAMPLER
    },
    .emit = upload_vs_state,

src/mesa/drivers/dri/i965/gen7_wm_state.c

@@ -227,7 +227,8 @@ const struct brw_tracked_state gen7_ps_state = {
 		_NEW_COLOR),
       .brw   = (BRW_NEW_FRAGMENT_PROGRAM |
 		BRW_NEW_PS_BINDING_TABLE |
-		BRW_NEW_BATCH),
+		BRW_NEW_BATCH |
+                BRW_NEW_PUSH_CONSTANT_ALLOCATION),
       .cache = (CACHE_NEW_SAMPLER |
 		CACHE_NEW_WM_PROG)
    },