[PATCH v3 4/5] gpu: drm: nova: build after nova-core metadata

[Alexandre Courbot <acourbot@nvidia.com>]

Point rustc to `nova-core`'s `.rmeta` file so `nova-drm` can use
`nova_core`'s types and functions at compile time.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
---
 drivers/gpu/drm/nova/Makefile | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/gpu/drm/nova/Makefile b/drivers/gpu/drm/nova/Makefile
index f8527b2b7b4a..6ed4ccbfbcdc 100644
--- a/drivers/gpu/drm/nova/Makefile
+++ b/drivers/gpu/drm/nova/Makefile
@@ -2,3 +2,18 @@
 
 obj-$(CONFIG_DRM_NOVA) += nova-drm.o
 nova-drm-y := nova.o
+
+nova_core_rmeta := drivers/gpu/nova-core/libnova_core.rmeta
+
+rustflags-y += --extern nova_core=$(objtree)/$(nova_core_rmeta)
+
+# `nova-drm` imports `nova-core` at compile time, so request `nova-core`'s
+# explicit metadata target before compiling nova.o.
+$(obj)/nova.o: | $(objtree)/$(nova_core_rmeta)
+
+# Build `nova-core`'s metadata by invoking make.
+#
+# This is ugly but only temporary until the build system natively supports
+# cross-crate dependencies.
+$(objtree)/$(nova_core_rmeta): FORCE
+	$(Q)$(MAKE) $(build)=drivers/gpu/nova-core $(nova_core_rmeta)

-- 
2.54.0