virgl: use hw-atomics instead of in-ssbo ones

Emulating atomics on top of ssbos can lead to too small max SSBO count,
so let's use the hw-atomics mechanism to expose atomic buffers instead.

Signed-off-by: Erik Faye-Lund <[email protected]>
Reviewed-by: Gurchetan Singh <[email protected]>

1 files changed, 23 insertions, 0 deletions

diff --git a/src/gallium/drivers/virgl/virgl_encode.c b/src/gallium/drivers/virgl/virgl_encode.c
index bcb14d8939a..29920b22be5 100644
--- a/src/gallium/drivers/virgl/virgl_encode.c
+++ b/src/gallium/drivers/virgl/virgl_encode.c
@@ -958,6 +958,29 @@ int virgl_encode_set_shader_buffers(struct virgl_context *ctx,
    return 0;
 }
 
+int virgl_encode_set_hw_atomic_buffers(struct virgl_context *ctx,
+                                       unsigned start_slot, unsigned count,
+                                       const struct pipe_shader_buffer *buffers)
+{
+   int i;
+   virgl_encoder_write_cmd_dword(ctx, VIRGL_CMD0(VIRGL_CCMD_SET_ATOMIC_BUFFERS, 0, VIRGL_SET_ATOMIC_BUFFER_SIZE(count)));
+
+   virgl_encoder_write_dword(ctx->cbuf, start_slot);
+   for (i = 0; i < count; i++) {
+      if (buffers) {
+         struct virgl_resource *res = virgl_resource(buffers[i].buffer);
+         virgl_encoder_write_dword(ctx->cbuf, buffers[i].buffer_offset);
+         virgl_encoder_write_dword(ctx->cbuf, buffers[i].buffer_size);
+         virgl_encoder_write_res(ctx, res);
+      } else {
+         virgl_encoder_write_dword(ctx->cbuf, 0);
+         virgl_encoder_write_dword(ctx->cbuf, 0);
+         virgl_encoder_write_dword(ctx->cbuf, 0);
+      }
+   }
+   return 0;
+}
+
 int virgl_encode_set_shader_images(struct virgl_context *ctx,
                                    enum pipe_shader_type shader,
                                    unsigned start_slot, unsigned count,