gallium: Add a helper for implementing PIPE_CAP_* default values.

One of the pains of implementing a gallium driver is filling in a million
pipe caps you don't know about yet when you're just starting out.  One of
the pains of working on gallium is copy-and-pasting your new PIPE_CAP into
each driver.  We can fix both of these by having each driver call into the
default helper from their default case, so that both sides can ignore each
other until they need to.

v2: fix i915g build, revert swr change to avoid breaking scons build
    (https://travis-ci.org/anholt/mesa/jobs/419739857)
v3: Rebase on 3 new gallium caps.

Reviewed-by: Marek Olšák <[email protected]> (v1)
Cc: Bruce Cherniak <[email protected]>
Cc: George Kyriazis <[email protected]>
Cc: Kenneth Graunke <[email protected]>

1 files changed, 3 insertions, 2 deletions

diff --git a/src/gallium/drivers/i915/i915_screen.c b/src/gallium/drivers/i915/i915_screen.c
index 103725ca5c8..1d98625f812 100644
--- a/src/gallium/drivers/i915/i915_screen.c
+++ b/src/gallium/drivers/i915/i915_screen.c
@@ -32,6 +32,7 @@
 #include "util/u_format_s3tc.h"
 #include "util/u_inlines.h"
 #include "util/u_memory.h"
+#include "util/u_screen.h"
 #include "util/u_string.h"
 
 #include "i915_reg.h"
@@ -425,9 +426,9 @@ i915_get_param(struct pipe_screen *screen, enum pipe_cap cap)
    case PIPE_CAP_COMPUTE:
    case PIPE_CAP_QUERY_BUFFER_OBJECT:
       return 0;
+
    default:
-      debug_printf("%s: Unknown cap %u.\n", __FUNCTION__, cap);
-      return 0;
+      return u_pipe_screen_get_param_defaults(screen, cap);
    }
 }