diff --git a/src/gallium/drivers/llvmpipe/lp_screen.c b/src/gallium/drivers/llvmpipe/lp_screen.c
index 69b82e984ec..06b706e15c4 100644
--- a/src/gallium/drivers/llvmpipe/lp_screen.c
+++ b/src/gallium/drivers/llvmpipe/lp_screen.c
@@ -504,10 +504,10 @@ llvmpipe_get_compute_param(struct pipe_screen *_screen,
       return sizeof(uint64_t);
    case PIPE_COMPUTE_CAP_GRID_DIMENSION:
       if (ret) {
-         uint32_t *grid_dim = ret;
+         uint64_t *grid_dim = ret;
          *grid_dim = 3;
       }
-      return sizeof(uint32_t);
+      return sizeof(uint64_t);
    case PIPE_COMPUTE_CAP_MAX_GLOBAL_SIZE:
       if (ret) {
          uint64_t *max_global_size = ret;