build u-boot image for sd as well as for emmc

 - switch to POSIX shell
 - set -u
 - make shellcheck clean
 - avoid cd in favour of -C and env --chdir
 - bump u-boot version from v2023.10-rc4 to v2023.10
 - verify top git hashes for u-boot and atf
 - verify that BPI Block Copy src is correct for sd and emmc
 - verify that sd and emmc images differ only in the Block Copy src

.gitlab-ci.yml

@@ -8,4 +8,5 @@ build:
     ./build.sh
   artifacts:
     paths:
-      - flash.bin
+      - flash-sd.bin
+      - flash-emmc.bin

build.sh

-#!/bin/bash
+#!/bin/sh
 
-set -xe
+set -xeu
 
 if [ -z ${SOURCE_DATE_EPOCH:+x} ] && git -C . rev-parse 2>/dev/null; then
-	export SOURCE_DATE_EPOCH=$(git log -1 --format=%ct)
+	SOURCE_DATE_EPOCH="$(git log -1 --format=%ct)"
+	export SOURCE_DATE_EPOCH
 fi
 export CROSS_COMPILE=aarch64-linux-gnu-
 export ARCH=arm64
 export LDFLAGS=--no-warn-rwx-segments
 
 # build Reset Configuration Word
-cd rcw/ls1028a-mnt-reform2
-make
-cd ../..
+make -C rcw/ls1028a-mnt-reform2
 
 # build u-boot
 # TODO: customize dts
-git clone --branch v2023.10-rc4 --depth 1 https://github.com/u-boot/u-boot.git
-cd u-boot
-#git checkout 252592214f79d8206c3cf0056a8827a0010214e0
-cp ../u-boot-config ./.config
-for p in ../patches/*.patch
-do
-    patch -p1 <"$p"
-done
-make -j$(nproc)
-cd ..
+if [ ! -d u-boot ]; then
+	git clone --branch v2023.10 --depth 1 https://github.com/u-boot/u-boot.git
+	if [ "$(git -C u-boot rev-parse --verify HEAD)" != "4459ed60cb1e0562bc5b40405e2b4b9bbf766d57" ]; then
+		echo "unexpected top atf commit" >&2
+		exit 1
+	fi
+	#git checkout 252592214f79d8206c3cf0056a8827a0010214e0
+	cp ./u-boot-config ./u-boot/.config
+	for p in ./patches/*.patch
+	do
+	    env --chdir=u-boot patch -p1 <"$p"
+	done
+	make -C u-boot -j"$(nproc)"
+fi
 
 # build ARM Trusted Firmware
-git clone https://source.mnt.re/reform/reform-ls1028a-atf.git atf
-
-export DDR_BIST=no
-export DDR_DEBUG=yes
-export DDR_PHY_DEBUG=yes
+if [ ! -d atf ]; then
+	git clone https://source.mnt.re/reform/reform-ls1028a-atf.git atf
+	if [ "$(git -C atf rev-parse --verify HEAD)" != "289be80193cd79029f1f897ddb9c175306bce227" ]; then
+		echo "unexpected top atf commit" >&2
+		exit 1
+	fi
+fi
 
-cd atf
-make -j$(nproc) PLAT=ls1028ardb fip pbl BOOT_MODE=sd RCW=../rcw/ls1028a-mnt-reform2/R_PSPH_0xb8be/rcw_1500_sdboot.bin BL33=../u-boot/u-boot-dtb.bin
-cd ..
+for bm in sd emmc; do
+	rm -f "atf/build/ls1028ardb/release/bl2_sd.pbl" "atf/build/ls1028ardb/release/bl2_emmc.pbl"
+	env DDR_BIST=no DDR_DEBUG=yes DDR_PHY_DEBUG=yes \
+		make -C atf -j"$(nproc)" \
+			PLAT=ls1028ardb fip pbl \
+			BOOT_MODE="$bm" \
+			RCW=../rcw/ls1028a-mnt-reform2/R_PSPH_0xb8be/rcw_1500_sdboot.bin \
+			BL33=../u-boot/u-boot-dtb.bin
+
+	cp "atf/build/ls1028ardb/release/bl2_$bm.pbl" "flash-$bm.bin"
+	dd if=atf/build/ls1028ardb/release/fip.bin of="flash-$bm.bin" bs=512 seek=2040
+done
 
-cp atf/build/ls1028ardb/release/bl2_sd.pbl flash.bin
-dd if=atf/build/ls1028ardb/release/fip.bin of=flash.bin bs=512 seek=2040
+# make sure that BPI Block Copy src is 9 for emmc and 8 for sd
+printf '\010' | cmp --ignore-initial=0:156 --bytes=1 - flash-sd.bin
+printf '\011' | cmp --ignore-initial=0:156 --bytes=1 - flash-emmc.bin
+# make sure that the remainder is identical
+cp flash-sd.bin flash-sd.bin.tmp
+printf '\011' | dd of=flash-sd.bin.tmp seek=1 bs=156 conv=notrunc
+cmp flash-sd.bin.tmp flash-emmc.bin
+rm flash-sd.bin.tmp