Prepare an SD card with Alpine Linux for a Raspberry Pi

README.md

What's this?

A quick-and dirty way to prepare an SD card on Mac OS X with Alpine Linux for a Raspberry Pi.

Prerequisites

• Mac OS X with GNU make and rsync installed, e.g. via homebrew.
• An unused SD card. 2GB are sufficient.

Usage

make will format the SD card, install Alpine, and eject the card.

For finer-grained control, use a combination of targets:

• format: Format the SD card
• alpine: Download Alpine (see Configuration below)
• mmc: Copy Alpine on the card, download it if needed
• config: Include an existing rpi.apkovl.tar.gz configuration on the card. Only usefule if you have saved one previously.
• splash: Add a boot splash. Caveat: This will disable the console. The splash screen must be named fbsplash.ppm.
• eject: Eject the card
• diff: Show differences between the Alpine distribution and the card contents
• clean: Remove the downloaded Alpine distribution.

Configuration

See the Editable configuration section in the Makefile:

• ARCH: Use armhf for any Pi, aarch64 for Pi 2 and 3.
• MAJOR_VERSION: Alpine release, e.g. 3.9
• MINOR_VERSION: Point release, e.g. 2 for release 3.9.2

Makefile

# Prepare an SD card with Alpine Linux for a Raspberry Pi
# See: https://wiki.alpinelinux.org/wiki/Raspberry_Pi

# Editable configuration
DISTRO = alpine
# ARCH = armhf
ARCH = aarch64
MAJOR_VERSION = 3.9
MINOR_VERSION = 2

# Derived configuration
URL = http://dl-cdn.alpinelinux.org/alpine/v$(MAJOR_VERSION)/releases/$(ARCH)/alpine-rpi-$(MAJOR_VERSION).$(MINOR_VERSION)-$(ARCH).tar.gz
VOLUME = $(shell find /Volumes -maxdepth 1 -depth 1 -uid $$USER)
DISK = $(shell mount | fgrep "$(VOLUME)" | cut -f1 -d ' ' | sed -e 's/s[0-9]$$//')
SPLASH = fbsplash.ppm

# Rules
.PHONY: mmc format clean eject check-mounted clean-mmc all config splash diff

all: format mmc eject

mmc: check-mounted $(DISTRO)
	rsync -av --modify-window=1 alpine/ $(VOLUME)/

splash:
	install -C $(SPLASH) $(VOLUME)

check-mounted: 
	@ [ -n "$(VOLUME)" ] || (echo No MMC mounted ; exit 1)
	
$(DISTRO):
	mkdir $@
	wget -qO - $(URL) | tar --disable-copyfile -C $@ -xzvf -
	touch $(DISTRO)/usercfg.txt
	# echo "dtoverlay=pi3-disable-wifi" >> $(DISTRO)/usercfg.txt
	mkdir -p $(DISTRO)/cache
	
clean:
	rm -r $(DISTRO)
	@ [ -z "$(VOLUME)" ] || diskutil eject $(VOLUME)

format: check-mounted
	diskutil eraseDisk FAT32 ALPINE MBR $(DISK)
	# diskutil partitionDisk $(DISK) MBR FAT32 ALPINE 256MB "Free Space" ROOT R
	sleep 1 ; $(MAKE) clean-mmc
	
config: rpi.apkovl.tar.gz check-mounted
	install -C $< $(VOLUME)

clean-mmc:
	- rm -rf "$(VOLUME)/.Spotlight-V100" "$(VOLUME)/.Trashes"
	- find "$(VOLUME)" -type f -name '._*' -delete
	rm -rf "$(VOLUME)/.fseventsd"
	rm -rf "$(VOLUME)/System Volume Information" # DOS
	mkdir -p "$(VOLUME)/.fseventsd"
	touch "$(VOLUME)/.fseventsd/no_log" "$(VOLUME)/.metadata_never_index" "$(VOLUME)/.Trashes"

eject: check-mounted
	rm -f "$(VOLUME)"/._\*
	diskutil eject "$(VOLUME)"

diff: check-mounted $(DISTRO)
	rsync -avn --delete --modify-window=1 \
		--exclude=cache --exclude=$(SPLASH) \
		alpine/ "$(VOLUME)/"

This is awesome -- thanks!