Expose boot eMMC partitions and mark them as bootable

Can be used to install for example Tow-Boot from a host PC

.gitignore

@@ -1,6 +1,7 @@
 /*.img
 /*.apk
 /initramfs/bin/busybox
+/initramfs/bin/mmc
 /initramfs-*
 /build
 /dtbs
@@ -10,6 +11,7 @@
 /src/linux-librem5
 /src/linux-sdm845
 /src/busybox
+/src/mmc-utils
 /src/u-boot
 /src/u-boot-pocketpc
 /src/u-boot-librem5

Makefile

@@ -1,3 +1,4 @@
+CC = aarch64-linux-gnu-gcc
 CROSS_FLAGS = ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu-
 CROSS_FLAGS_BOOT = CROSS_COMPILE=aarch64-linux-gnu-
 
@@ -120,11 +121,17 @@ initramfs/bin/busybox: src/busybox src/busybox_config
 	@$(MAKE) -C src/busybox O=../../build/busybox $(CROSS_FLAGS)
 	@cp build/busybox/busybox initramfs/bin/busybox
 
+initramfs/bin/mmc-utils: src/mmc-utils
+	@echo "MAKE  $@"
+	@mkdir -p build/mmc-utils
+	@$(MAKE) -C src/mmc-utils O=../../build/mmc-utils CFLAGS="-Wno-error -static" CC=$(CC)
+	@cp src/mmc-utils/mmc initramfs/bin/mmc
+	
 splash/%.ppm.gz: splash/%.ppm
 	@echo "GZ    $@"
 	@gzip < $< > $@
 	
-initramfs-%.cpio: initramfs/bin/busybox initramfs/init initramfs/init_functions.sh splash/%.ppm.gz splash/%-error.ppm.gz
+initramfs-%.cpio: initramfs/bin/busybox initramfs/bin/mmc-utils initramfs/init initramfs/init_functions.sh splash/%.ppm.gz splash/%-error.ppm.gz
 	@echo "CPIO  $@"
 	@rm -rf initramfs-$*
 	@cp -r initramfs initramfs-$*
@@ -309,6 +316,12 @@ src/busybox:
 	@wget https://www.busybox.net/downloads/busybox-1.32.0.tar.bz2
 	@tar -xf busybox-1.32.0.tar.bz2 --strip-components 1 -C src/busybox
 
+src/mmc-utils:
+	@echo "WGET  mmc-utils"
+	@mkdir src/mmc-utils
+	@wget https://git.kernel.org/pub/scm/utils/mmc/mmc-utils.git/snapshot/mmc-utils-0eea71e4f22a837ed59e607743767df2d038825e.tar.gz
+	@tar -xf mmc-utils-0eea71e4f22a837ed59e607743767df2d038825e.tar.gz --strip-components 1 -C src/mmc-utils
+
 .PHONY: clean cleanfast purism-librem5
 
 purism-librem5: initramfs-purism-librem5.gz kernel-librem5.gz u-boot-librem5.bin src/purism-librem5.txt dtbs/librem5/imx8mq-librem5-r2.dtb

README.md

@@ -46,6 +46,10 @@ The dependencies are:
 - aarch64-linux-gnu- toolchain
 - u-boot tools
 - mtools
+- swig
+- dtc
+- cpio
+- bc
 
 Additional dependencies for the Purism Librem 5:
 - arm-none-eabi- toolchain
@@ -72,5 +76,6 @@ Generates an image for every supported platform in parallel
 - [Busybox](https://busybox.net) - which is [GPLv2](https://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html).
 - [postmarketOS](https://postmarketos.org) scripts - which is [GPLv2](https://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html).
 - [Pine64's kernel fork](https://gitlab.com/pine64-org/linux) - which is [GPLv2](https://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html).
-- [U-Boot](https://github.com/u-boot/u-boot) - which has [multiple licenses](https://github.com/u-boot/u-boot/tree/master/Licenses)
+- [U-Boot](https://github.com/u-boot/u-boot) - which has [multiple licenses](https://github.com/u-boot/u-boot/tree/master/Licenses).
+- [mmc-utils](https://www.kernel.org/doc/html/latest/driver-api/mmc/mmc-tools.html) - which is [GPLv2](https://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html).
 

initramfs/init_functions.sh

@@ -58,10 +58,27 @@ setup_usb_configfs() {
 	echo $EMMC > $CONFIGFS/g1/functions/"$usb_mass_storage_function"/lun.0/file
 	echo $SD > $CONFIGFS/g1/functions/"$usb_mass_storage_function"/lun.1/file
 
+	if [ -n "$EMMC_BOOT" ]; then
+		echo "$EMMC_BOOT" > $CONFIGFS/g1/functions/"$usb_mass_storage_function"/lun.2/file
+	fi
+
 	# Rename the mass storage device
 	echo "JumpDrive eMMC" > $CONFIGFS/g1/functions/"$usb_mass_storage_function"/lun.0/inquiry_string
 	echo "JumpDrive microSD" > $CONFIGFS/g1/functions/"$usb_mass_storage_function"/lun.1/inquiry_string
 
+	if [ -n "$EMMC_BOOT" ]; then
+		echo "JumpDrive eMMC Boot" > $CONFIGFS/g1/functions/"$usb_mass_storage_function"/lun.2/inquiry_string
+
+		# Make sure the boot partitions are rw
+		for f in /sys/block/mmcblk*boot*/force_ro; do
+			echo 0 > "$f"
+		done
+
+		# Mark the boot partitions as bootable
+		mmc bootbus set single_hs x1 x4 "$EMMC_BOOT"
+		mmc bootpart enable 1 1 "$EMMC_BOOT"
+	fi
+
 	# Link the rndis/mass_storage instance to the configuration
 	ln -s $CONFIGFS/g1/functions/"$usb_rndis_function" $CONFIGFS/g1/configs/c.1 \
 		|| echo "  Couldn't symlink $usb_rndis_function"

src/info-pine64-pinephone.sh

@@ -2,6 +2,7 @@ PLATFORM=pine64-pinephone
 MANUFACTURER=Pine64
 PRODUCT=PinePhone
 EMMC=/dev/mmcblk2
+EMMC_BOOT=/dev/mmcblk2boot1
 SD=/dev/mmcblk0
 LED=red\:indicator
 TRIGGER=mmc2