Hi guys,
I am a newbie of seL4 and I am trying to get some understanding of it.
So, my first question is about the build system of seL4:
1. Why cmake has been taken to build it? I think there are at least two
shortcomings about current build system based on CMakeLists.txt:
- Some build options were implied in the CMakeLists.txt. It's not
easy to get a complete and comprehensive understanding of all the
options. And some options depends on other options. Such as,
./init-build.sh -DPLATFORM=odroidc2 -DAARCH64=1
A new guys couldn't get a support list of PLATFORM option, and
know AARCH64 is only for ARMv8 SoC easily.
- There are too much branches of platform or SoC Architectures. Such
as:
if(KernelArchARM)
include_directories("include/arch/arm/armv/${KernelArmArmV}/")
include_directories("include/arch/arm/armv/${KernelArmArmV}/${KernelWordSize}")
endif()
if(KernelArmMach STREQUAL "exynos")
include_directories("include/plat/exynos_common/")
endif()
if(KernelArchRiscV)
include_directories("include/arch/${KernelArch}/arch/${KernelWordSize}")
include_directories("include/plat/${KernelPlatform}/plat/${KernelWordSize}")
endif()
Linux Build System places the special build options and source files
into the directory related with each architectures, and will
generated a configure file (.config) during building. It's very good
in my opinion.
In Android Build System, a given project building inherits a common
build options set, and update these parts only related the given
project. It's very good for integration.
And I want to know if there is a plan to update the build system or
accept patches from volunteer?
2. I notice that, all kernel source files have been concatenated into a
kernel_all.c, and compile the kernel_all.c. Is there some special
reason for this step? It's a slight strange for me?
Anyway, I am a new guy. I just want to understand it and if I could
provide something to change it. Any comments are appreciated.
Thanks,
Jerry
