iris: fix SSBO indexing

st/nir offsets SSBO indexes by MaxABOs.  This is not what we want,
as it bloats the binding tables.  We'll need to adjust it to use
info->num_abos as the offset and buffer base instead.  For now,
just use the inefficient format to get us rolling.  We can add a
PIPE_CAP later.

3 files changed, 14 insertions, 3 deletions

diff --git a/src/gallium/drivers/iris/iris_context.h b/src/gallium/drivers/iris/iris_context.h
index 98af24cf223..cda649127c7 100644
--- a/src/gallium/drivers/iris/iris_context.h
+++ b/src/gallium/drivers/iris/iris_context.h
@@ -43,6 +43,9 @@ struct blorp_params;
 #define IRIS_RESOURCE_FLAG_DYNAMIC_MEMZONE (PIPE_RESOURCE_FLAG_DRV_PRIV << 2)
 
 #define IRIS_MAX_TEXTURE_SAMPLERS 32
+/* IRIS_MAX_ABOS and IRIS_MAX_SSBOS must be the same. */
+#define IRIS_MAX_ABOS 16
+#define IRIS_MAX_SSBOS 16
 #define IRIS_MAX_VIEWPORTS 16
 
 #define IRIS_DIRTY_COLOR_CALC_STATE         (1ull <<  0)
diff --git a/src/gallium/drivers/iris/iris_screen.c b/src/gallium/drivers/iris/iris_screen.c
index f98b17bb1fb..105ac0e5f62 100644
--- a/src/gallium/drivers/iris/iris_screen.c
+++ b/src/gallium/drivers/iris/iris_screen.c
@@ -384,8 +384,9 @@ iris_get_shader_param(struct pipe_screen *pscreen,
    case PIPE_SHADER_CAP_MAX_TEXTURE_SAMPLERS:
    case PIPE_SHADER_CAP_MAX_SAMPLER_VIEWS:
    case PIPE_SHADER_CAP_MAX_SHADER_IMAGES:
-   case PIPE_SHADER_CAP_MAX_SHADER_BUFFERS:
       return IRIS_MAX_TEXTURE_SAMPLERS;
+   case PIPE_SHADER_CAP_MAX_SHADER_BUFFERS:
+      return IRIS_MAX_ABOS + IRIS_MAX_SSBOS;
    case PIPE_SHADER_CAP_MAX_HW_ATOMIC_COUNTERS:
    case PIPE_SHADER_CAP_MAX_HW_ATOMIC_COUNTER_BUFFERS:
       return 0;
diff --git a/src/gallium/drivers/iris/iris_state.c b/src/gallium/drivers/iris/iris_state.c
index bc27de8f7d8..13371908e3e 100644
--- a/src/gallium/drivers/iris/iris_state.c
+++ b/src/gallium/drivers/iris/iris_state.c
@@ -2680,8 +2680,15 @@ iris_populate_binding_table(struct iris_context *ice,
       bt_map[s++] = use_const_buffer(batch, cbuf);
    }
 
-   for (int i = 0; i < info->num_abos + info->num_ssbos; i++) {
-      bt_map[s++] = use_ssbo(batch, ice, shs, i);
+   /* XXX: st is wasting 16 binding table slots for ABOs.  Should add a cap
+    * for changing nir_lower_atomics_to_ssbos setting and buffer_base offset
+    * in st_atom_storagebuf.c so it'll compact them into one range, with
+    * SSBOs starting at info->num_abos.  Ideally it'd reset num_abos to 0 too
+    */
+   if (info->num_abos + info->num_ssbos > 0) {
+      for (int i = 0; i < IRIS_MAX_ABOS + info->num_ssbos; i++) {
+         bt_map[s++] = use_ssbo(batch, ice, shs, i);
+      }
    }
 
 #if 0