Merge pull request #56 from brain-hackers/buildroot-experiment

Enhance buildroot rootfs

.github/workflows/build.yml

@@ -12,7 +12,7 @@ jobs:
     outputs:
       upload_url: ${{ steps.create_release.outputs.upload_url }}
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
         with:
           fetch-depth: 0
           submodules: false
@@ -41,7 +41,7 @@ jobs:
     runs-on: ubuntu-20.04
     needs: [create_release]
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
         with:
           submodules: true
       - name: Workaround for apt update failure
@@ -91,7 +91,7 @@ jobs:
     runs-on: ubuntu-20.04
     needs: [create_release]
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
         with:
           submodules: true
       - name: Workaround for apt update failure
@@ -154,7 +154,7 @@ jobs:
             lilo: gen3_7.bin
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
         with:
           submodules: true
       - name: Workaround for apt update failure
@@ -200,7 +200,7 @@ jobs:
           - model: h1
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
         with:
           submodules: true
       - name: Workaround for apt update failure
@@ -234,7 +234,7 @@ jobs:
     runs-on: ubuntu-20.04
     needs: [create_release]
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
         with:
           submodules: true
       - name: Make /opt writable
@@ -277,7 +277,7 @@ jobs:
     runs-on: ubuntu-20.04
     needs: [create_release]
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
         with:
           submodules: true
       - name: Workaround for apt update failure

.gitmodules

@@ -13,3 +13,6 @@
 [submodule "brainlilo"]
 	path = brainlilo
 	url = https://github.com/brain-hackers/brainlilo.git
+[submodule "buildroot"]
+	path = buildroot
+	url = https://github.com/brain-hackers/buildroot.git

Makefile

@@ -135,7 +135,6 @@ lilobuild:
 liloclean:
 	make -C ./brainlilo clean
 
-
 brainux:
 	@if [ "$(shell uname)" != "Linux" ]; then \
 		echo "Debootstrap is only available in Linux!"; \
@@ -150,15 +149,26 @@ brainux:
 	fi
 	sudo cp /usr/bin/qemu-arm-static brainux/usr/bin/
 	sudo cp ./os-brainux/setup_brainux.sh brainux/
+	sudo ./os-brainux/override-pre.sh ./os-brainux/override ./brainux
 	sudo -E chroot brainux /setup_brainux.sh
 	sudo rm brainux/setup_brainux.sh
 	sudo ./os-brainux/override.sh ./os-brainux/override ./brainux
 
+buildroot_rootfs:
+	make -C buildroot brain_imx28_defconfig
+	make -C buildroot -j 12
+	sudo mkdir -p buildroot_rootfs
+	sudo tar -C ./buildroot_rootfs -xf buildroot/output/images/rootfs.tar
+
 image/sd.img: clean_work
-	./image/build_image.sh
+	./image/build_image.sh brainux sd.img 3072
 
 image/sd_x1.img: clean_work
-	./image/build_image_x1.sh
+	./image/build_image_x1.sh brainux sd_x1.img 3072
+
+image/sd_buildroot.img: clean_work
+	./image/build_image.sh buildroot_rootfs sd_buildroot.img 128
+
 
 .PHONY:
 clean_work:

README.md

@@ -94,8 +94,8 @@ Build Linux
 1. Confirm that `linux-brain/arch/arm/boot/zImage` exists.
 
 
-Bootstrap Debian 11 (bullseye)
-------------------------------
+Build a Debian rootfs
+---------------------
 
 1. Run `make ldefconfig lbuild`.
 
@@ -107,9 +107,23 @@ Bootstrap Debian 11 (bullseye)
 
 1. Confirm that `image/sd.img` is built and burn it to an SD card.
 
+
+Build a Buildroot rootfs
+------------------------
+
+Buildroot rootfs aims to be the most lightweight rootfs for experimental use. `make buildroot_rootfs` runs the defconfig target for rootfs-only build and then builds the rootfs tarball and a CPIO archive for initramfs. `make image/sd_buildroot.img` makes a bootable SD image in `image` directory like the typical Brainux SD image.
+
+If you want to customize the build of Buildroot, `cd` into `buildroot` and use the following targets:
+
+ - `make menuconfig` to change the configuration
+ - `make` to build the rootfs (`-j` option might give you extra speed)
+
+`image/sd_buildroot.img` target expects presence of the tarball at `buildroot/output/images/rootfs.tar`. You'll have to `clean` and rebuild every time you change the Buildroot's config before making the SD image.
+
+
 Known issues
 ----------------------------------------
-If you using gcc 10 for host compiler, `make ubuild` may fail.  
+If you use GCC 10 for the host compiler, `make ubuild` may fail.
 To complete build, open `/u-boot-brain/scripts/dtc/dtc-lexer.lex.c` or `/u-boot-brain/scripts/dtc/dtc-parser.tab.c` then comment out `YYLTYPE yylloc;`
 
 Watch changes in submodules & auto-build

buildroot

@@ -0,0 +1 @@
+Subproject commit cf3ea901082f470449bd174272d8407e039522b2

image/build_image.sh

@@ -5,7 +5,10 @@ JOBS=$(nproc)
 REPO=$(git rev-parse --show-toplevel)
 WORK=${REPO}/image/work
 LINUX=${REPO}/linux-brain
-IMG=${REPO}/image/sd.img
+ROOTFS=$1
+IMG_NAME=$2
+IMG=${REPO}/image/${IMG_NAME}
+SIZE_M=$3
 export CROSS_COMPILE=arm-linux-gnueabi-
 
 mkdir -p ${WORK}
@@ -34,7 +37,7 @@ for i in "a7200" "sh1" "sh2" "sh3" "sh4" "sh5" "sh6" "sh7"; do
     esac
 done
 
-dd if=/dev/zero of=${IMG} bs=1M count=3072
+dd if=/dev/zero of=${IMG} bs=1M count=${SIZE_M}
 
 START1=2048
 SECTORS1=$((1024 * 1024 * 64 / 512))
@@ -49,7 +52,7 @@ sfdisk ${IMG} < ${WORK}/part.sfdisk
 
 sudo kpartx -av ${IMG}
 
-LOOPDEV=$(losetup -l | grep sd.img | grep -o 'loop.' | tail -n 1)
+LOOPDEV=$(losetup -l | grep ${IMG_NAME} | grep -o 'loop.' | tail -n 1)
 
 sudo mkfs.fat -n boot -F32 -v -I /dev/mapper/${LOOPDEV}p1
 sudo mkfs.ext4 -L rootfs /dev/mapper/${LOOPDEV}p2
@@ -71,13 +74,13 @@ sudo touch "${LILO}/index.din"
 sudo touch "${LILO}/AppMain.cfg"
 sudo cp ${REPO}/brainlilo/*.dll "${LILO}/"
 sudo cp ${REPO}/brainlilo/BrainLILO.exe "${LILO}/AppMain_.exe"
-gzip -d ${REPO}/image/exeopener.exe.gz
+gzip -cd ${REPO}/image/exeopener.exe.gz > ${REPO}/image/exeopener.exe
 sudo cp ${REPO}/image/exeopener.exe "${LILO}/AppMain.exe"
 
 sudo mkdir -p ${WORK}/p1/loader
 sudo cp ${WORK}/lilobin/*.bin ${WORK}/p1/loader/
 
-sudo cp -ra ${REPO}/brainux/* ${WORK}/p2/
+sudo cp -ra ${REPO}/${ROOTFS}/* ${WORK}/p2/
 
 sudo umount ${WORK}/p1 ${WORK}/p2
 sudo kpartx -d ${IMG}

os-brainux/override-pre.sh

@@ -0,0 +1,10 @@
+#!/bin/bash
+
+set -uex -o pipefail
+
+SRC=$1
+DST=$2
+
+install -g root -o root -m 0644 $SRC/lib/systemd/system/boot.mount $DST/lib/systemd/system/boot.mount
+install -g root -o root -m 0644 $SRC/lib/systemd/system/rndis_gadget.service $DST/lib/systemd/system/rndis_gadget.service
+install -g root -o root -m 0755 $SRC/usr/bin/enable_rndis_gadget $DST/usr/bin/enable_rndis_gadget

os-brainux/override/lib/systemd/system/boot.mount

@@ -0,0 +1,10 @@
+[Unit]
+Description=Mount boot partition
+
+[Mount]
+What=/dev/mmcblk1p1
+Where=/boot
+Options=ro
+
+[Install]
+WantedBy=multi-user.target

os-brainux/override/lib/systemd/system/rndis_gadget.service

@@ -0,0 +1,9 @@
+[Unit]
+Description=Enable RNDIS USB Gadget
+
+[Service]
+Type=oneshot
+ExecStart=/usr/bin/enable_rndis_gadget
+
+[Install]
+WantedBy=multi-user.target

os-brainux/override/usr/bin/enable_rndis_gadget

@@ -0,0 +1,25 @@
+#!/bin/sh
+
+g=/sys/kernel/config/usb_gadget/eth
+
+mkdir ${g}
+
+echo "0x3066" > ${g}/bcdDevice
+echo "1" > ${g}/os_desc/use
+echo "0xcd" > ${g}/os_desc/b_vendor_code
+echo "MSFT100" > ${g}/os_desc/qw_sign
+
+mkdir ${g}/functions/rndis.rn0
+echo "RNDIS" > ${g}/functions/rndis.rn0/os_desc/interface.rndis/compatible_id
+echo "5162001" > ${g}/functions/rndis.rn0/os_desc/interface.rndis/sub_compatible_id
+echo "8a:15:8b:44:3a:02" > ${g}/functions/rndis.rn0/dev_addr
+echo "8a:15:8b:44:3a:01" > ${g}/functions/rndis.rn0/host_addr
+
+mkdir ${g}/configs/c.1
+ln -s ${g}/functions/rndis.rn0 ${g}/configs/c.1/
+
+echo "ci_hdrc.0" > ${g}/UDC
+
+sleep 1
+ifconfig usb0 up
+dhclient

os-brainux/setup_brainux.sh

@@ -136,6 +136,12 @@ ttymxc0
 ttyLP0
 EOF
 
+# Enable /boot mount
+systemctl enable boot.mount
+
+# Enable RNDIS gadget
+systemctl enable rndis_gadget
+
 # Get wild
 cat <<EOF > /etc/apt/sources.list
 deb http://deb.debian.org/debian bullseye main contrib non-free

os-buildroot/override/root/blink.sh

@@ -0,0 +1,112 @@
+#!/bin/sh
+set -u
+
+VERBOSE=0
+PIN=""
+SLEEP=1
+GPIOS=""
+
+while getopts "hvr:p:s:" OPT; do
+    case "$OPT" in
+    h)
+        echo "Usage:   blink.sh [-hv] [-r PIN_RANGE_FROM-PIN_RANGE_TO] [-p PIN] [-s SLEEP_SEC]"
+        echo "Example: blink.sh -r 0-10 -p 12"
+        echo "         (blink from GPIO 0 to 10 and 12)"
+        exit 0
+        ;;
+    v)
+        VERBOSE=1
+        ;;
+    r)
+        RE='^([0-9]+)-([0-9]+)$'
+        if echo $OPTARG | grep -qvE $RE; then
+            echo "Error: invalid range: $OPTARG"
+            exit 1
+        fi
+        FROM=$(echo $OPTARG | sed -E "s/$RE/\\1/")
+        TO=$(echo $OPTARG | sed -E "s/$RE/\\2/")
+        GPIOS="$GPIOS$(seq -s " " $FROM $TO) "
+        ;;
+    p)
+        if echo $OPTARG | grep -qvE "^[0-9]+$"; then
+            echo "Error: invalid pin number: $OPTARG"
+            exit 1
+        fi
+        GPIOS="$GPIOS$OPTARG "
+        ;;
+    s)
+        if echo $OPTARG | grep -qvE "^[0-9]+$"; then
+            echo "Error: invalid sleep duration: $OPTARG"
+            exit 1
+        fi
+        SLEEP=$OPTARG
+        ;;
+    esac
+done
+
+if [ $VERBOSE -eq 1 ]; then
+    echo "Pins to iterate over: $GPIOS"
+fi
+
+if [ "$(id -u)" -ne "0" ]; then
+    echo "Error: please run as root"
+    exit 1
+fi
+
+AVAILABLE_GPIOS=""
+
+export_gpio() {
+    echo $1 > /sys/class/gpio/export
+}
+
+set_direction() {
+    echo out > /sys/class/gpio/gpio$1/direction
+}
+
+set_value() {
+    echo $2 > /sys/class/gpio/gpio$1/value
+}
+
+for i in $GPIOS; do
+    if [ ! -e "/sys/class/gpio/gpio$i" ]; then
+        export_gpio $i 2>/dev/null
+        if [ $? -ne 0 ]; then
+            echo "Error: failed to export the pin $i"
+            continue
+        fi
+    fi
+
+    set_direction $i 2>/dev/null
+    if [ $? -ne 0 ]; then
+        # Ignore the failure if the actual direction is out
+        if grep -vq "out" /dsys/class/gpio/gpio$i/direction; then
+            echo "Error: failed to set the direction of the pin $i to out"
+            continue
+        fi
+    fi
+
+    AVAILABLE_GPIOS="$AVAILABLE_GPIOS$i "
+done
+
+echo "Available GPIOs: $AVAILABLE_GPIOS"
+
+while [ 1 ]; do
+    for i in $AVAILABLE_GPIOS; do
+        set_value $i 1 2>/dev/null
+        if [ $? -ne 0 ]; then
+            echo "Warning: failed to set the value of the pin $i to high"
+        fi
+    done
+
+    sleep $SLEEP
+
+    for i in $AVAILABLE_GPIOS; do
+        set_value $i 0 2>/dev/null
+        if [ $? -ne 0 ]; then
+            echo "Warning: failed to set the value of the pin $i to low"
+        fi
+    done
+
+    sleep $SLEEP
+done
+