Patches for xenomai & Robert C Nelson Kernel for Xenomai
Installation steps:
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Get Robert C Nelson Kernel build environment first - tag v3.13.4-bone5 from git://github.com/RobertCNelson/linux-dev.git
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Get Xenomai master from git://git.xenomai.org/xenomai-2.6.git
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Build default Robert C Nelson kernel running the script build_kernel.sh (this will download all the required tools, sources, patches etc.). This step is not strictly necessary, because it is sufficient to get the tools and patch the kernel, but building default Robert's kernel guarantees that the all necessary patches will be aplied
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After the patches were applied in previous step you can give tag to the patched Robert's kernel tree - cd KERNEL; git tag 3.13.4-bone5
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in directory KERNEL apply patch v3.13.4-bone5_ipipe.patch.gz zcat v3.13.4-bone5_ipipe.patch.gz | patch -p1
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copy/overwrite right config from repo stored in directory configs/ to directory KERNEL overwriting files .config & .config.old - the config includes only basic drivers & has all debug enabled I wanted. When somebody wishes to change it please change the settings concerning debugging. Warning!!! Ipipe debugging/tracing options seem to be very expensive in CPU time.
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go to your Xenomai repo from step (2)
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apply patch xenomai-2.6.3_master_3.13.patch.gz to xenomai cd ${XENO_DIR}; zcat xenomai-2.6.3_master_3.13.patch.gz | patch -p1
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installa xenomai as usual: ./scripts/prepare-kernel.sh --kernel=${RCNKernelPath}, etc...
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rebuild & install the kernel in BBB (there are various places where it is described - eewiki is one of those ).
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test & eventually enjoy (surely moderately, because there are some serious flaws, mosty concerning mmc read / writes with external SDcard).
The flaws:
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the version is completely unsupported by Xenomai or IPIPE teams! Please don't bother the guys with any problems concerning the patches.
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xeno_rtdmtest & xeno_klat seem to introduce plenty of trouble concerning system stability. I had to rewrite rootfs because of FS errors caused by MMC subsystem malfunction. So !!!BE CAREFUL!!! and make a backup before playing with the xenomai version. I've seen something like "[ 240.244050] omap_hsmmc 48060000.mmc: MMC start dma failure" and later it was not funny anymore!
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only BBB is handled with the patch - the rest of the platforms at least partially. I've join'ed not applied ipipe-3.10 patches in ipipe-3.10-patches_skipped.patch.gz for somebody who wishes to apply the rest or apply the patches for some other platforms similar to BBB.
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during heavy IO load I've seen "Unable to handle kernel NULL pointer dereference at virtual address 000004fc" in dmesg. the dereference was in function cleanup_event(). I've seen it only once, but haven't performed the testing well.
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test xenomai/bin/regression/native/sigdebug gives error "relaxed mutex owner FAILURE rt_task_body:102: rt_mutex_acquire returned 0 instead of -4 - Success" therefore I'm not sure about rt_mutex handling quality at all.
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loadig xeno_klat can cause immidiate system freeze
In directory configs/ are stored config files for kernel rebuild. The ones don't include all possible driver configurations, but include some debugging options for ipipe / xenomai, also for some am335x peripherals.
In directory tests/ xenomai test results are stored.