directions derived from

https://www.raspberrypi.org/documentation/linux/kernel/building.md

http://elinux.org/RPi_Upstream_Kernel_Compilation

http://elinux.org/RPi_U-Boot

good resources

https://www.raspberrypi.org/documentation/configuration/config-txt.md

http://cellux.github.io/articles/diy-linux-with-buildroot-part-1/

http://blog.flexvdi.com/2015/02/25/enabling-hyp-mode-on-the-raspberry-pi-2/

http://blog.flexvdi.com/2015/03/17/enabling-kvm-virtualization-on-the-raspberry-pi-2/

http://kariddi.blogspot.com/2012/08/raspberry-pi-bare-metal-part-1-boot.html

Eric Anholt's open GPU driver work

http://www.serverphorums.com/read.php?12,1257154

http://anholt.livejournal.com/

https://dri.freedesktop.org/wiki/VC4/

http://www.broadcom.com/docs/support/videocore/VideoCoreIV-AG100-R.pdf

sudo screen /dev/ttyUSB0 115200

C-a \       (quit)        Kill all windows and terminate screen.

--- rpi kernel source ---

git clone --branch rpi-4.1.y --depth 1 https://github.com/raspberrypi/linux.git

--- mainline kernel source ---

git clone --depth 1 git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git

git clone --depth 1 git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git

git clone --depth 1 --branch linux-4.5.y git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git

cp linux-rpi/arch/arm/configs/bcm2709_defconfig linux/arch/arm/configs/bcm2709_defconfig

from the rpi-4.5.y branch

--- kernel compilation ---

export KERNEL=kernel7

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- clean

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- mrproper

rpi: make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- bcm2709_defconfig

mainline: make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- bcm2835_defconfig

enable loadable module support {module unloading, module versioning support, source checksum for all modules}

enable kernel features -> SMP

floating point emulation -> advanced SIMD (NEON) extension support

floating point emulation -> Support for NEON in kernel mode

enable kernel features -> high memory support

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- menuconfig

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- zImage modules dtbs -j 8 > buildoutput.log 2> buildoutput2.log

later - play with more kernel configs

kernel message: consider using a HIGHMEM enabled kernel

autofs4

kdbus

systemctl status kmod-static-nodes.service

select General Setup -> uselib syscall

Broadcom SoC Support -> Broadcom BCM2835 family

Kernel features -> Xen guest support on ARM

Device drivers -> Virtualization drivers

Device drivers -> Xen driver support -> all enabled

Virtualization

Device Drivers ---> USB support ---> DesignWare USB2 DRD Core Support and check both Host only mode and DWC2 Platform

Networking support -> Networking Options -> TCP/IP networking -> IP: kernel level autoconfiguration

Networking support -> Networking Options -> TCP/IP networking -> IP: DHCP support

File Systems -> Network File Systems -> Root file system on NFS

--- create minimal image & mount it ---

sudo mkdir /mnt/ramdisk

sudo mount -t tmpfs -o size=6g tmpfs /mnt/ramdisk

dd if=/dev/zero of=/mnt/ramdisk/minimal.img bs=512M count=1

sudo losetup /dev/loop0 /mnt/ramdisk/minimal.img

sudo losetup -d /dev/loop0

sudo gparted /dev/loop0

create partitions & click to mount

sudo kpartx -av /mnt/ramdisk/minimal.img

export BOOT=/media/stew/boot

export ROOTFS=/media/stew/ext4

--- rpi kernel & modules install ---

sudo make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- INSTALL_MOD_PATH=$ROOTFS modules_install

sudo scripts/mkknlimg arch/arm/boot/zImage $BOOT/$KERNEL.img

sudo cp arch/arm/boot/dts/*.dtb $BOOT

mkdir $BOOT/overlays/

sudo cp arch/arm/boot/dts/overlays/*.dtb* $BOOT/overlays/

sudo cp arch/arm/boot/dts/overlays/README $BOOT/overlays/

--- mainline kernel & modules install ---

sudo make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- INSTALL_MOD_PATH=$ROOTFS modules_install

cp arch/arm/boot/zImage $BOOT/$KERNEL.img

cp arch/arm/boot/dts/bcm2836-rpi-2-b.dtb $BOOT

--- ubuntu bootstrap ---

directions derived in part from https://wiki.ubuntu.com/ARM/RootfsFromScratch/QemuDebootstrap

and in part from http://wiki.xen.org/wiki/Xen_ARM_with_Virtualization_Extensions/RootFilesystem

sudo mount -o remount,dev $ROOTFS

sudo debootstrap --foreign --arch=armhf --include=ca-certificates --variant=minbase wily $ROOTFS http://us.ports.ubuntu.com/

todo: leaving off --variant=minbase produces errors, so exclude python3 and resolvconf

unused options:

--verbose

--components=main,restricted,universe,multiverse

fakeroot

http://archive.raspbian.com/raspbian

http://ports.ubuntu.com/ubuntu-ports/

--no-check-gpg

try to see if this gets rid of the "Keyring file not available at /usr/share/keyrings/ubuntu-archive-keyring.gpg; switching to https mirror https://mirrors.kernel.org/debian" warning?

--keyring=/usr/share/keyrings/ubuntu-archive-keyring.gpg

... nope it didn't.

sudo cp `which qemu-arm-static` $ROOTFS/usr/bin/

sudo chroot $ROOTFS

/debootstrap/debootstrap --second-stage

unused commands:

sudo mount -t proc proc $ROOTFS/proc

sudo cp /etc/resolv.conf $ROOTFS/etc/resolv.conf

exit

sudo chroot $ROOTFS

passwd

adduser stew

echo "stew-pi" > /etc/hostname

not needed: echo "127.0.0.1 localhost qemu" > /etc/hosts

todo: sources.list

sudo rm $ROOTFS/usr/bin/qemu-arm-static

--- u-boot ---

git clone --depth 1 git://git.denx.de/u-boot.git

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- clean

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- mrproper

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- rpi_2_defconfig

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- menuconfig

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- -j 8

cp ./u-boot.bin $BOOT

./tools/mkimage -A arm -O linux -T script -C none -n boot.scr -d ../stewconfig/boot-mainline.scr $BOOT/boot.scr.uimg

./tools/mkimage -A arm -O linux -T script -C none -n boot.scr -d ../stewconfig/boot-xen.scr $BOOT/boot.scr.uimg

unused mkimage options:

-a 0x00000000

-e 0x00000000

-n "RPi2 Boot Script"

boot-rpi.scr:

boot-mainline.scr:

boot-xen.scr (broken):

--- rpi firmware & config ---

cd ..

git clone --depth 1 git://github.com/raspberrypi/firmware.git

cp firmware/boot/bootcode.bin $BOOT

cp firmware/boot/start.elf $BOOT

cp firmware/boot/fixup.dat $BOOT

cp stewconfig/cmdline.txt $BOOT

rpi loader: cp stewconfig/config.txt $BOOT

u-boot: cp stewconfig/config_u-boot.txt $BOOT/config.txt

sudo cp stewconfig/fstab $ROOTFS/etc/fstab

cmdline.txt:

dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait

config_u-boot.txt:

kernel=u-boot.bin

fstab:

--- unmount stuff ---

sudo umount $BOOT

sudo umount $ROOTFS

sudo kpartx -d /mnt/ramdisk/minimal.img

sudo losetup -d /dev/loop0

shasum /mnt/ramdisk/minimal.img

mv /mnt/ramdisk/minimal.img .

sudo umount /mnt/ramdisk

--- xen (broken) ---

required libs

sudo apt-get install zlib1g-dev python-dev libncurses5-dev libssl-dev libx11-dev uuid-dev libyajl-dev libaio-dev libglib2.0-dev libpixman-1-dev pkg-config bridge-utils iproute bison flex gettext iasl libc6-dev libc6-dev-i386

optional libs

sudo apt-get install ocaml-nox ocaml-findlib cmake markdown figlet libsystemd-daemon-dev libnl-3-200 libnl-3-dev

links

http://wiki.xen.org/wiki/Category:XenARM

http://wiki.xen.org/wiki/Xen_ARM_with_Virtualization_Extensions

http://wiki.xen.org/wiki/Dom0_Kernels_for_Xen

http://wiki.xen.org/wiki/XenParavirtOps

http://wiki.xen.org/wiki/Mainline_Linux_Kernel_Configs

git clone --depth 1 git://xenbits.xen.org/xen.git

docs/misc/arm/early-printk.txt: rpi: printk with pl011 for Raspberry Pi 2

xen/arch/arm/Rules.mk: EARLY_PRINTK_rpi            := pl011,0x7e201000,115200

make XEN_TARGET_ARCH=arm32 CROSS_COMPILE=arm-linux-gnueabihf- CONFIG_EARLY_PRINTK=rpi clean

make XEN_TARGET_ARCH=arm32 CROSS_COMPILE=arm-linux-gnueabihf- CONFIG_EARLY_PRINTK=rpi mrproper

make -C xen XEN_TARGET_ARCH=arm32 CROSS_COMPILE=arm-linux-gnueabihf- CONFIG_EARLY_PRINTK=rpi menuconfig

make XEN_TARGET_ARCH=arm32 CROSS_COMPILE=arm-linux-gnueabihf- CONFIG_EARLY_PRINTK=rpi dist-xen

../u-boot/tools/mkimage -A arm -C none -T kernel -n "XEN" -d xen/xen xen-uImage

../u-boot/tools/mkimage -A arm -C none -T kernel -a 0x01C00000 -e 0x01C00000 -n "XEN" -d xen/xen xen-uImage

cp xen-uImage $BOOT

notes below

debug=y

DESTDIR=/some/path

* To build xen and tools using a cross compiler:

./configure --build=x86_64-unknown-linux-gnu --host=aarch64-linux-gnu

make

make install

add some stuff to boot.scr:

mmc dev 0

setenv fdtfile bcm2836-rpi-2-b.dtb

 setenv bootargs "earlyprintk console=tty1 console=ttyAMA0 root=/dev/mmcblk0p2 rootfstype=ext4 rootwait"

setenv xen_addr_r 0x01C00000

 setenv kernel_addr_r 0x01000000

 setenv fdt_addr_r 0x00000100

 setenv xen_bootargs 'sync_console console=dtuart dtuart=/serial@7e201000 dom0_mem=512M'

 setenv dom0_bootargs 'console=hvc0 ignore_loglevel psci=enable clk_ignore_unused root=/dev/mmcblk1p3'

 saveenv

fatload mmc 0:1 ${kernel_addr_r} kernel7.img

fatload mmc 0:1 ${fdt_addr_r} ${fdtfile}

fatload mmc 0:1 $xen_addr_r xen-uImage

 fdt addr $fdt_addr_r

 fdt resize

 fdt set /chosen xen,xen-bootargs \"$xen_bootargs\"

 fdt set /chosen xen,dom0-bootargs \"$dom0_bootargs\"

 fdt mknode /chosen modules

 fdt set /chosen/modules '#address-cells' <1>

 fdt set /chosen/modules '#size-cells' <1>   

 fdt mknode /chosen/modules module@0

 fdt set /chosen/modules/module@0 compatible xen,linux-zimage xen,multiboot-module

 fdt set /chosen/modules/module@0 reg <$kernel_addr_r 0x00c00000>

bootm ${xen_addr_r} - ${fdt_addr_r}

 bootz ${xen_addr_r} - ${fdt_addr_r}

   fdt addr ${fdt_addr_r}

   fdt resize

   

   fdt set /chosen \#address-cells <1>

   fdt set /chosen \#size-cells <1>

   

   fdt mknod /chosen module@0

   fdt set /chosen/module@0 compatible "xen,linux-zimage" "xen,multiboot-module"

   fdt set /chosen/module@0 reg <${kernel_addr_r} 0x00c00000>

   fdt set /chosen/module@0 bootargs "<DOMAIN 0 COMMAND LINE>"

--- reference - interrupt controller info ---

http://lists.infradead.org/pipermail/linux-rpi-kernel/2015-July/thread.html

http://lists.infradead.org/pipermail/linux-rpi-kernel/2015-August/thread.html

linux/Documentation/devicetree/bindings/interrupt-controller/brcm,bcm2836-l1-intc.txt

linux/Documentation/devicetree/bindings/interrupt-controller/brcm,bcm2835-armctrl-ic.txt

linux/Documentation/devicetree/bindings/interrupt-controller/arm,gic.txt

linux/arch/arm/boot/dts/bcm283x.dtsi

linux/arch/arm/boot/dts/bcm2836.dtsi

--- reference - install rpi kernel on raspbian image ---

stew@Stew-SS:~/Desktop/raspi$ sudo losetup /dev/loop0 2016-03-18-raspbian-jessie-lite.img 

stew@Stew-SS:~/Desktop/raspi$ sudo fdisk -l /dev/loop0

Disk /dev/loop0: 1361 MB, 1361051648 bytes

255 heads, 63 sectors/track, 165 cylinders, total 2658304 sectors

Units = sectors of 1 * 512 = 512 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0x6f92008e

      Device Boot      Start         End      Blocks   Id  System

/dev/loop0p1            8192      131071       61440    c  W95 FAT32 (LBA)

60.00 MiB gparted reports fat16, lba flag

/dev/loop0p2          131072     2658303     1263616   83  Linux

1.21 GiB ext4

sudo losetup -o 4194304 /dev/loop0 2016-03-18-raspbian-jessie-lite.img

sudo losetup -o 67108864 /dev/loop1 2016-03-18-raspbian-jessie-lite.img

click on the icon to mount

/media/stew/boot

/media/stew/eda95d8a-9cdd-4224-96d0-890b4791600c

sudo make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- INSTALL_MOD_PATH=/media/stew/eda95d8a-9cdd-4224-96d0-890b4791600c modules_install

sudo cp /media/stew/boot/$KERNEL.img /media/stew/boot/$KERNEL-backup.img

sudo scripts/mkknlimg arch/arm/boot/zImage /media/stew/boot/$KERNEL.img

sudo cp arch/arm/boot/dts/*.dtb /media/stew/boot

sudo cp arch/arm/boot/dts/overlays/*.dtb* /media/stew/boot/overlays/

sudo cp arch/arm/boot/dts/overlays/README /media/stew/boot/overlays/

--- obsolete Busybox (missing init stuff) ---

cd busybox

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- clean

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- mrproper

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- defconfig

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- menuconfig

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- -j 8

sudo make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- CONFIG_PREFIX=$ROOTFS install

sudo mkdir -p $ROOTFS/{etc,boot,proc,sys,mnt,dev}

sudo cp stewconfig/fstab $ROOTFS/etc/fstab

mknod -m 644 myinitfs/dev/console c 5 1

mknod -m 644 myinitfs/dev/loop0 b 7 0