3dd024f384
Currently, the KERNEL_DEBUG_TIMESTAMPS is not working as expected at rebuild. That is, even if we set it to "1", the kernel build time is not changed. The problem could be reproduced by the following steps. 1. bitbake core-image-minimal; start image and check `uname -a` output. 2. set in local.conf: KERNEL_DEBUG_TIMESTAMPS = "1" 3. bitbake core-image-minimal; start image and check `uname -a` output. It's expected that after enabling KERNEL_DEBUG_TIMESTAMPS, the kernel build time will be set to current date. But it's not. This is because the compile.h was not re-generated when do_compile task was re-executed. In mkcompile_h, we have: """ # Only replace the real compile.h if the new one is different, # in order to preserve the timestamp and avoid unnecessary # recompilations. # We don't consider the file changed if only the date/time changed, # unless KBUILD_BUILD_TIMESTAMP was explicitly set (e.g. for # reproducible builds with that value referring to a commit timestamp). # A kernel config change will increase the generation number, thus # causing compile.h to be updated (including date/time) due to the # changed comment in the # first line. """ It has made it very clear that it will not be re-generated unless we have KBUILD_BUILD_TIMESTAMP set explicitly. So we set this variable explicitly in do_compile to fix this issue. (From OE-Core rev: 640ac18b2daed698adbf849a5aef55f5de9e5db5) Signed-off-by: Chen Qi <Qi.Chen@windriver.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> (cherry picked from commit 1b68c2d2d385013a1c535ef81172494302a36d74) Signed-off-by: Steve Sakoman <steve@sakoman.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Poky
Poky is an integration of various components to form a pre-packaged build system and development environment which is used as a development and validation tool by the Yocto Project. It features support for building customised embedded style device images and custom containers. There are reference demo images ranging from X11/GTK+ to Weston, commandline and more. The system supports cross-architecture application development using QEMU emulation and a standalone toolchain and SDK suitable for IDE integration.
Additional information on the specifics of hardware that Poky supports is available in README.hardware. Further hardware support can easily be added in the form of BSP layers which extend the systems capabilities in a modular way. Many layers are available and can be found through the layer index.
As an integration layer Poky consists of several upstream projects such as BitBake, OpenEmbedded-Core, Yocto documentation, the 'meta-yocto' layer which has configuration and hardware support components. These components are all part of the Yocto Project and OpenEmbedded ecosystems.
The Yocto Project has extensive documentation about the system including a reference manual which can be found at https://docs.yoctoproject.org/
OpenEmbedded is the build architecture used by Poky and the Yocto project. For information about OpenEmbedded, see the OpenEmbedded website.
Contribution Guidelines
The project works using a mailing list patch submission process. Patches should be sent to the mailing list for the repository the components originate from (see below). Throughout the Yocto Project, the README files in the component in question should detail where to send patches, who the maintainers are and where bugs should be reported.
A guide to submitting patches to OpenEmbedded is available at:
https://www.openembedded.org/wiki/How_to_submit_a_patch_to_OpenEmbedded
There is good documentation on how to write/format patches at:
https://www.openembedded.org/wiki/Commit_Patch_Message_Guidelines
Where to Send Patches
As Poky is an integration repository (built using a tool called combo-layer), patches against the various components should be sent to their respective upstreams:
OpenEmbedded-Core (files in meta/, meta-selftest/, meta-skeleton/, scripts/):
- Git repository: https://git.openembedded.org/openembedded-core/
- Mailing list: openembedded-core@lists.openembedded.org
BitBake (files in bitbake/):
- Git repository: https://git.openembedded.org/bitbake/
- Mailing list: bitbake-devel@lists.openembedded.org
Documentation (files in documentation/):
- Git repository: https://git.yoctoproject.org/cgit/cgit.cgi/yocto-docs/
- Mailing list: docs@lists.yoctoproject.org
meta-yocto (files in meta-poky/, meta-yocto-bsp/):
- Git repository: https://git.yoctoproject.org/cgit/cgit.cgi/meta-yocto
- Mailing list: poky@lists.yoctoproject.org
If in doubt, check the openembedded-core git repository for the content you intend to modify as most files are from there unless clearly one of the above categories. Before sending, be sure the patches apply cleanly to the current git repository branch in question.