boot/arm-trusted-firmware: add option BR2_TARGET_ARM_TRUSTED_FIRMWARE_UBOOT_BL33_IMAGE

Currently, when BR2_TARGET_ARM_TRUSTED_FIRMWARE_UBOOT_AS_BL33 is
enabled, the arm-trusted-firmware package assumes that the BL33 image
provided by U-Boot is u-boot.bin. However for some platforms, the name
may be different (for example u-boot-dtb.bin). To support such use
cases, this commit adds a string option
BR2_TARGET_ARM_TRUSTED_FIRMWARE_UBOOT_BL33_IMAGE to configure the
U-Boot image name, which defaults to u-boot.bin to preserve backward
compatibility.

Signed-off-by: Jerry Huang <jerry.huang@nxp.com>
Reviewed-by: Sergey Matyukevich <geomatsi@mail.com>
[Thomas: rewrite commit log and Config.in help text]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

boot/arm-trusted-firmware/Config.in

@@ -124,6 +124,17 @@ config BR2_TARGET_ARM_TRUSTED_FIRMWARE_UBOOT_AS_BL33
 	  gets built before ATF, and that the appropriate BL33
 	  variable pointing to u-boot.bin is passed when building ATF.
 
+if BR2_TARGET_ARM_TRUSTED_FIRMWARE_UBOOT_AS_BL33
+
+config BR2_TARGET_ARM_TRUSTED_FIRMWARE_UBOOT_BL33_IMAGE
+	string "U-Boot BL33 image name"
+	default "u-boot.bin"
+	help
+	  Name of the U-Boot BL33 image to include in ATF, it must
+	  have been installed to BINARIES_DIR by the U-Boot package.
+
+endif
+
 config BR2_TARGET_ARM_TRUSTED_FIRMWARE_ADDITIONAL_VARIABLES
 	string "Additional ATF build variables"
 	help

boot/arm-trusted-firmware/arm-trusted-firmware.mk

@@ -70,7 +70,8 @@ endif
 endif # BR2_TARGET_ARM_TRUSTED_FIRMWARE_BL32_OPTEE
 
 ifeq ($(BR2_TARGET_ARM_TRUSTED_FIRMWARE_UBOOT_AS_BL33),y)
-ARM_TRUSTED_FIRMWARE_MAKE_OPTS += BL33=$(BINARIES_DIR)/u-boot.bin
+ARM_TRUSTED_FIRMWARE_UBOOT_BIN = $(call qstrip,$(BR2_TARGET_ARM_TRUSTED_FIRMWARE_UBOOT_BL33_IMAGE))
+ARM_TRUSTED_FIRMWARE_MAKE_OPTS += BL33=$(BINARIES_DIR)/$(ARM_TRUSTED_FIRMWARE_UBOOT_BIN)
 ARM_TRUSTED_FIRMWARE_DEPENDENCIES += uboot
 endif