[PATCH v6 5/6] mach-snapdragon: add kconfig infra for building MBN files

[Casey Connolly]

Add a qualcomm specific Makefile fragment to make u-boot.mbn a build
target and introduce a kconfig option to build it by default on relevant
platforms via CONFIG_BUILD_TARGET.

Signed-off-by: Casey Connolly <casey.connolly at linaro.org>
---
 Kconfig                          |  1 +
 arch/arm/mach-snapdragon/Kconfig | 11 +++++++++++
 board/qualcomm/config.mk         | 14 ++++++++++++++
 3 files changed, 26 insertions(+)

diff --git a/Kconfig b/Kconfig
index 8428d039a1c0..183c8096030d 100644
--- a/Kconfig
+++ b/Kconfig
@@ -557,8 +557,9 @@ config BUILD_TARGET
 	default "u-boot-with-spl.sfp" if ARCH_SOCFPGA_GEN5
 	default "u-boot.itb" if !BINMAN && SPL_LOAD_FIT && (ARCH_ROCKCHIP || \
 				RISCV || ARCH_ZYNQMP)
 	default "u-boot.kwb" if (ARCH_KIRKWOOD || ARMADA_32BIT) && !SPL
+	default "u-boot.mbn" if ARCH_SNAPDRAGON && QCOM_GENERATE_MBN
 	help
 	  Some SoCs need special image types (e.g. U-Boot binary
 	  with a special header) as build targets. By defining
 	  CONFIG_BUILD_TARGET in the SoC / board header, this
diff --git a/arch/arm/mach-snapdragon/Kconfig b/arch/arm/mach-snapdragon/Kconfig
index d3de8693b5a8..6329cbb9215e 100644
--- a/arch/arm/mach-snapdragon/Kconfig
+++ b/arch/arm/mach-snapdragon/Kconfig
@@ -41,5 +41,16 @@ config SYS_CONFIG_NAME
 	  This option contains information about board configuration name.
 	  Based on this option include/configs/<CONFIG_SYS_CONFIG_NAME>.h header
 	  will be used for board configuration.
 
+config QCOM_GENERATE_MBN
+	bool "Generate an MBN-compatible ELF binary"
+	default n
+	help
+	  Enable this if you intend to flash U-Boot as a first-stage bootloader.
+	  The build system will generate a board-specific ELF file with the appropriate
+	  MBN hash segments and test keys.
+
+	  New platforms can be added to tools/qcom/mkmbn/mkmbn.py if they aren't already
+	  supported.
+
 endif
diff --git a/board/qualcomm/config.mk b/board/qualcomm/config.mk
new file mode 100644
index 000000000000..769e4a51ca01
--- /dev/null
+++ b/board/qualcomm/config.mk
@@ -0,0 +1,14 @@
+# SPDX-License-Identifier: GPL-2.0+
+#
+# (C) Copyright Linaro Ltd.
+#
+# Qualcomm specific make target for MBN signed ELF files.
+#
+
+# Create Qualcomm signed elf images
+CMD_MKMBN = $(srctree)/tools/qcom/mkmbn/mkmbn.py
+quiet_cmd_mkmbn = MBN     $@
+      cmd_mkmbn = $(CMD_MKMBN) $<
+
+u-boot.mbn: u-boot.bin FORCE
+	$(call if_changed,mkmbn)

-- 
2.53.0