gallium: all drivers should accept two-dimensional constant buffer indexing

Most older drivers seem to just ignore the Dimension setting, so virtually
no changes should be needed.

Acked-by: Roland Scheidegger <[email protected]>
Tested-by: Dieter Nützel <[email protected]>
Reviewed-by: Timothy Arceri <[email protected]>

2 files changed, 4 insertions, 9 deletions

diff --git a/src/gallium/auxiliary/nir/tgsi_to_nir.c b/src/gallium/auxiliary/nir/tgsi_to_nir.c
index 733eca0764b..aa715dcae2d 100644
--- a/src/gallium/auxiliary/nir/tgsi_to_nir.c
+++ b/src/gallium/auxiliary/nir/tgsi_to_nir.c
@@ -624,7 +624,7 @@ ttn_src_for_file_and_index(struct ttn_compile *c, unsigned file, unsigned index,
          assert(!dim);
          break;
       case TGSI_FILE_CONSTANT:
-         if (dim) {
+         if (dim && (dim->Index > 0 || dim->Indirect)) {
             op = nir_intrinsic_load_ubo;
          } else {
             op = nir_intrinsic_load_uniform;
diff --git a/src/gallium/docs/source/screen.rst b/src/gallium/docs/source/screen.rst
index be14ddd0c0d..93d94a48e6b 100644
--- a/src/gallium/docs/source/screen.rst
+++ b/src/gallium/docs/source/screen.rst
@@ -446,21 +446,16 @@ support different features.
 * ``PIPE_SHADER_CAP_MAX_CONST_BUFFER_SIZE``: The maximum size per constant buffer in bytes.
 * ``PIPE_SHADER_CAP_MAX_CONST_BUFFERS``: Maximum number of constant buffers that can be bound
   to any shader stage using ``set_constant_buffer``. If 0 or 1, the pipe will
-  only permit binding one constant buffer per shader, and the shaders will
-  not permit two-dimensional access to constants.
+  only permit binding one constant buffer per shader.
 
 If a value greater than 0 is returned, the driver can have multiple
-constant buffers bound to shader stages. The CONST register file can
-be accessed with two-dimensional indices, like in the example below.
+constant buffers bound to shader stages. The CONST register file is
+accessed with two-dimensional indices, like in the example below.
 
 DCL CONST[0][0..7]       # declare first 8 vectors of constbuf 0
 DCL CONST[3][0]          # declare first vector of constbuf 3
 MOV OUT[0], CONST[0][3]  # copy vector 3 of constbuf 0
 
-For backwards compatibility, one-dimensional access to CONST register
-file is still supported. In that case, the constbuf index is assumed
-to be 0.
-
 * ``PIPE_SHADER_CAP_MAX_TEMPS``: The maximum number of temporary registers.
 * ``PIPE_SHADER_CAP_TGSI_CONT_SUPPORTED``: Whether the continue opcode is supported.
 * ``PIPE_SHADER_CAP_INDIRECT_INPUT_ADDR``: Whether indirect addressing