microblaze: Support simpleImage.dts make target

Instead of remembering to specify DTB= on the make commandline, this commit
allows the much friendlier make simpleImage.<dts>
where <dts>.dts is expected to be found in arch/microblaze/boot/dts/
The resulting vmlinux, with the compiled DTS linked in, will be copied to
boot/simpleImage.<dts>

This mirrors the same functionality as on PowerPC,
albeit achieving it in a slightly different way.

+ strip simpleImage file
The size of output file is very similar to linux.bin.

vmlinux - full elf without fdt blob
simpleImage.<dtb name>.unstrip - full elf with fdt blob
simpleImage.<dtb name> - stripped elf with fdt blob

Add symlink to generic system.dts in platform folder

Signed-off-by: John Williams <john.williams@petalogix.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>

1 files changed, 23 insertions, 4 deletions

diff --git a/arch/microblaze/Makefile b/arch/microblaze/Makefile
index 737a4dc72ed9c..34187354304a6 100644
--- a/arch/microblaze/Makefile
+++ b/arch/microblaze/Makefile
@@ -53,22 +53,41 @@ core-y += arch/microblaze/platform/
 
 boot := arch/microblaze/boot
 
+# Are we making a simpleImage.<boardname> target? If so, crack out the boardname
+DTB:=$(subst simpleImage.,,$(filter simpleImage.%, $(MAKECMDGOALS)))
+
+ifneq ($(DTB),)
+	core-y	+= $(boot)/
+endif
+
 # defines filename extension depending memory management type
 ifeq ($(CONFIG_MMU),)
 MMU := -nommu
 endif
 
-export MMU
+export MMU DTB
 
 all: linux.bin
 
+BOOT_TARGETS = linux.bin linux.bin.gz simpleImage.%
+
 archclean:
 	$(Q)$(MAKE) $(clean)=$(boot)
 
-linux.bin linux.bin.gz: vmlinux
+$(BOOT_TARGETS): vmlinux
 	$(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
 
 define archhelp
-  echo  '* linux.bin    - Create raw binary'
-  echo  '  linux.bin.gz - Create compressed raw binary'
+  echo '* linux.bin    - Create raw binary'
+  echo '  linux.bin.gz - Create compressed raw binary'
+  echo '  simpleImage.<dt> - ELF image with $(arch)/boot/dts/<dt>.dts linked in'
+  echo '                   - stripped elf with fdt blob
+  echo '  simpleImage.<dt>.unstrip - full ELF image with fdt blob'
+  echo '  *_defconfig      - Select default config from arch/microblaze/configs'
+  echo ''
+  echo '  Targets with <dt> embed a device tree blob inside the image'
+  echo '  These targets support board with firmware that does not'
+  echo '  support passing a device tree directly. Replace <dt> with the'
+  echo '  name of a dts file from the arch/microblaze/boot/dts/ directory'
+  echo '  (minus the .dts extension).'
 endef