aarch64: Add make target to flash U-Boot to the SparX-5i eval board

board/aarch64/README.md

@@ -55,5 +55,13 @@ DBGACK |o o| GND
 | `TCK`       | `SCK`          |
 | `TDO`       | `MISO`         |
 
+With the cable in place, build U-Boot with the correct configuration:
+
+    make fireant_boot_defconfig && make
+
+To flash it to the board, connect the cable to `J4` and run:
+
+    make board-sparx-flash-uboot
+
 [BB3]: http://dangerousprototypes.com/docs/Bus_Blaster#Bus_Blaster_v3
 [dangerspi]: https://github.com/wkz/dangerspi

board/aarch64/board.mk

@@ -5,3 +5,13 @@ board-enable-sparx-fit:
 	@BR2_PREFIX= ./utils/config --file $(BR2_CONFIG) \
 	 	--enable FIT_IMAGE \
 	 	--set-str FIT_KERNEL_LOAD_ADDR "0x7 0x00000000"
+
+.PHONY: board-sparx-flash-uboot
+board-sparx-flash-uboot: $(BINARIES_DIR)/u-boot.bin
+	@grep -q 'BR2_TARGET_UBOOT_BOARD_DEFCONFIG="mscc_fireant_pcb135_emmc"' $(BR2_CONFIG) || \
+		{ echo Build tree does not seem to be configured for SparX-5i eval board; exit 1; }
+	@echo Erasing...
+	@dangerspi.py erase 0 0x100000
+	@echo Programming...
+	@dangerspi.py write 0 0x100000 <$<
+	@echo Done...