[yocto] custom linux kernel recipe

Tue Aug 30 04:33:24 PDT 2016

Thanks for your answer Bruce !

I've applied the patch you've mentioned 
(http://git.yoctoproject.org/cgit/cgit.cgi/poky-contrib/commit/?h=zedd/kernel&id=0fe665e69983fe9ef38319deedcb78ecd7b165cf) 
to my recipe, linux-stable_4.7.bb, providing the dtb:

KERNEL_DEVICETREE_qemuarm = "versatile-pb.dtb"
QEMU_DTB_qemuarm = "zImage-versatile-pb"

I've also updated my runqemu-internal script to add the dtb file to the 
qemu options.
For some reason the QEMU_DTB variable is empty so I hard coded the dtb 
filename just to make a test.

So now, when running the qemuarm machine, the dtb file is provided with 
the "dtb" parameter.
The result is the same, a black screen.
As mentioned, my recipe is using the 4.7.2 kernel: the Latest Stable Kernel

Then I applied the patch to the linux-yocto-dev.bb recipe (I'm on 
krogoth) - this is using kernel 4.8
This boots correctly - without the dtb patch the result is the same: 
black screen.

But I'm stuck with the 4.7.2 kernel - the Latest Stable Kernel, any 
suggestions on how to accomplish this ? It looks like the patch is not 
enough for kernel 4.7.2.

Thanks in advance.
Mircea

On 08/29/2016 04:02 PM, Bruce Ashfield wrote:
> On 2016-08-29 07:34 AM, Mircea Gliga wrote:
>> Hi
>>
>> I'm using krogoth and trying to create a qemu arm machine with the
>> latest stable kernel 4.7.2.
>> I created a recipe,recipes-kernel/linux/linux-stable_4.7.bb, in my layer
>> with the following contents:
>>
>> ---
>> inherit kernel
>> require recipes-kernel/linux/linux-yocto.inc
>>
>> FILESEXTRAPATHS_prepend := "${THISDIR}/${PN}-${PV}:"
>>
>> KBRANCH ?= "linux-4.7.y"
>>
>> SRCREV ?= "84fae3f89282ce86a0c0da30e35fe66dbcadda6f"
>>
>> KBRANCH_sama5d4-xplained ?= "linux-4.7.y"
>> SRCREV_machine_sama5d4-xplained ?=
>> "84fae3f89282ce86a0c0da30e35fe66dbcadda6f"
>>
>> KERNEL_DEVICETREE_sama5d4-xplained = "at91-sama5d4_xplained.dtb"
>>
>> KBRANCH_qemuarm ?= "linux-4.7.y"
>>
>> SRC_URI =
>> "git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git;bareclone=1;branch=${KBRANCH}" 
>>
>>
>>
>> SRC_URI += "file://defconfig"
>>
>> LINUX_VERSION = "4.7.2"
>> PV = "${LINUX_VERSION}+git${SRCPV}"
>>
>> COMPATIBLE_MACHINE = "sama5d4-xplained|qemuarm"
>> ---
>>
>> As you can see, I'm planning to use this recipe for multiple machines.
>>
>> In the recipes-kernel/linux/linux-stable-4.7/qemuarm/ directory I copied
>> the defconfig file.
>> I've created this defconfig file by:
>> * sourcing my build environment, from my build directory: source
>> build-qemu/tmp/environment-setup-armv5e-poky-linux-gnueabi
>> * running "make vexpress_defconfig" in the kernel build directory. (I've
>> used this tutorial
>> https://balau82.wordpress.com/2012/03/31/compile-linux-kernel-3-2-for-arm-and-emulate-with-qemu/ 
>>
>> )
>> This outputed:
>>
>> ---
>> $ make vexpress_defconfig
>>   GEN     ./Makefile
>> #
>> # configuration written to .config
>> #
>> ---
>>
>> * renamed .config to defconfig and then copy it in
>> recipes-kernel/linux/linux-stable-4.7/qemuarm/
>>
>> In my local.conf I've added, in order to use my custom kernel for the
>> qemu machine:
>>
>> ---
>> MACHINE ??= "qemuarm"
>> PREFERRED_PROVIDER_virtual/kernel_qemuarm ?= "linux-stable"
>> ---
>>
>> Everything builds without errors (bitbake linux-stable), but when I
>> start qemu (runqemu qemuarm) I only get a black screen in the QEMU 
>> window.
>> This is the output of $ runqemu qemuarm:
>> ---
>> Continuing with the following parameters:
>> KERNEL:
>> [/home/user/yocto-k/build-qemu/tmp/deploy/images/qemuarm/zImage-qemuarm.bin] 
>>
>>
>> ROOTFS:
>> [/home/user/yocto-k/build-qemu/tmp/deploy/images/qemuarm/custom-minimal-image-qemuarm-20160823102657.rootfs.ext4] 
>>
>>
>> FSTYPE: [ext4]
>> Setting up tap interface under sudo
>> [sudo] password for user:
>> Acquiring lockfile for tap0...
>> Running qemu-system-arm...
>> /home/user/yocto-k/build-qemu/tmp/sysroots/x86_64-linux/usr/bin/qemu-system-arm 
>>
>> -kernel
>> /home/user/yocto-k/build-qemu/tmp/deploy/images/qemuarm/zImage-qemuarm.bin 
>>
>> -net nic,model=virtio -net
>> tap,vlan=0,ifname=tap0,script=no,downscript=no -M versatilepb -drive
>> file=/home/user/yocto-k/build-qemu/tmp/deploy/images/qemuarm/custom-minimal-image-qemuarm-20160823102657.rootfs.ext4,if=virtio,format=raw 
>>
>> -no-reboot -show-cursor -usb -usbdevice tablet -no-reboot -m 128 -serial
>> mon:vc -serial null -append "root=/dev/vda rw console=ttyAMA0,115200
>> console=tty ip=192.168.7.2::192.168.7.1:255.255.255.0 mem=128M
>> highres=off rootfstype=ext4 "
>> ---
>>
>> This is my build configuration:
>> Build Configuration:
>> BB_VERSION        = "1.30.0"
>> BUILD_SYS         = "x86_64-linux"
>> NATIVELSBSTRING   = "universal"
>> TARGET_SYS        = "arm-poky-linux-gnueabi"
>> MACHINE           = "qemuarm"
>> DISTRO            = "poky"
>> DISTRO_VERSION    = "2.1.1"
>> TUNE_FEATURES     = "arm armv5 thumb dsp"
>> TARGET_FPU        = "soft"
>> meta
>> meta-poky
>> meta-yocto-bsp    = "krogoth:12eb72ee3b02f826a156ff4e396c770f2b93571e"
>> meta-smartcom     = "master:121dbfb9f416de8442bbad1dc150271fd50b38e6"
>> meta-atmel        = "krogoth:01ff01073dd8fa1463b7841fb0a8caa44559acdd"
>> meta-oe
>> meta-networking
>> meta-python       = "krogoth:247b1267bbe95719cd4877d2d3cfbaf2a2f4865a"
>>
>>
>> When I use the default linux-yocto as the preferred kernel (v 4.4)
>> everything works as expected.
>> Do you have any suggestions? Is there a problem with the defconfig file
>> provided ?
>> What is the proper way of creating this defconfig file for qemuarm ?
>> I also tried using the .config file created when building
>> linux-yocto_4.4 but got the same result.
>> I tried the defconfig used for the
>
> You need a variant of the patch I'm going to submit later today:
>
> http://git.yoctoproject.org/cgit/cgit.cgi/poky-contrib/commit/?h=zedd/kernel&id=0fe665e69983fe9ef38319deedcb78ecd7b165cf 
>
>
> I'm about to bump linux-yocto to 4.8, which ran into the device tree
> changes for the versatile/vexpress class boards. You are seeing the
> same thing.
>
>
> Bruce
>
>
>>
>> Thanks !
>>
>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.yoctoproject.org/pipermail/yocto/attachments/20160830/d54850e9/attachment.html>