board/freescale/common/imx: add support for i.MX 8M Plus

Almost identical as i.MX 8M Nano, with a couple of differences:
- different ATF load address [1]
- different entry point [2]

[1] https://source.denx.de/u-boot/u-boot/-/commit/e8e2703a3050feb8d2e6473d806c5277d5e3236f
[2] https://source.denx.de/u-boot/u-boot/-/blob/v2021.04-rc4/configs/imx8mp_evk_defconfig#L14

Signed-off-by: Stephane Viau <stephane.viau@oss.nxp.com>
Reviewed-by: Gary Bisson <gary.bisson@boundarydevices.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

board/freescale/common/imx/imx8-bootloader-prepare.sh

@@ -29,6 +29,13 @@ main ()
 		rm -f ${BINARIES_DIR}/u-boot.its
 
 		${HOST_DIR}/bin/mkimage_imx8 -v v2 -fit -loader ${BINARIES_DIR}/u-boot-spl-ddr.bin 0x912000 -second_loader ${BINARIES_DIR}/u-boot.itb 0x40200000 0x60000 -out ${BINARIES_DIR}/imx8-boot-sd.bin
+	elif grep -Eq "^BR2_PACKAGE_FREESCALE_IMX_PLATFORM_IMX8MP=y$" ${BR2_CONFIG}; then
+		cat ${BINARIES_DIR}/u-boot-spl.bin ${BINARIES_DIR}/ddr_fw.bin > ${BINARIES_DIR}/u-boot-spl-ddr.bin
+		BL31=${BINARIES_DIR}/bl31.bin BL33=${BINARIES_DIR}/u-boot-nodtb.bin ATF_LOAD_ADDR=0x00970000 ${HOST_DIR}/bin/mkimage_fit_atf.sh ${UBOOT_DTB} > ${BINARIES_DIR}/u-boot.its
+		${HOST_DIR}/bin/mkimage -E -p 0x3000 -f ${BINARIES_DIR}/u-boot.its ${BINARIES_DIR}/u-boot.itb
+		rm -f ${BINARIES_DIR}/u-boot.its
+
+		${HOST_DIR}/bin/mkimage_imx8 -v v2 -fit -loader ${BINARIES_DIR}/u-boot-spl-ddr.bin 0x920000 -second_loader ${BINARIES_DIR}/u-boot.itb 0x40200000 0x60000 -out ${BINARIES_DIR}/imx8-boot-sd.bin
 	else
 		${HOST_DIR}/bin/mkimage_imx8 -commit > ${BINARIES_DIR}/mkimg.commit
 		cat ${BINARIES_DIR}/u-boot.bin ${BINARIES_DIR}/mkimg.commit > ${BINARIES_DIR}/u-boot-hash.bin

board/freescale/common/imx/post-image.sh

@@ -40,6 +40,8 @@ genimage_type()
 		echo "genimage.cfg.template_imx8"
 	elif grep -Eq "^BR2_PACKAGE_FREESCALE_IMX_PLATFORM_IMX8MN=y$" ${BR2_CONFIG}; then
 		echo "genimage.cfg.template_imx8"
+	elif grep -Eq "^BR2_PACKAGE_FREESCALE_IMX_PLATFORM_IMX8MP=y$" ${BR2_CONFIG}; then
+		echo "genimage.cfg.template_imx8"
 	elif grep -Eq "^BR2_PACKAGE_FREESCALE_IMX_PLATFORM_IMX8X=y$" ${BR2_CONFIG}; then
 		echo "genimage.cfg.template_imx8"
 	elif grep -Eq "^BR2_LINUX_KERNEL_INSTALL_TARGET=y$" ${BR2_CONFIG}; then