As __start must be placed at a precise location, a separate, explicit
input section is needed to guarantee this.
Why is this an issue ? NuttX uses --entry=__start which puts __start in
its correct location, but out-of-tree builds won't work, so it more robust
to use an explicit section for the startup code and enforce its placement
in the linker script.
When I try to set priorities in certain programs, such as init_priority(HIGH_PRIORITY), I've noticed that during linking, there's no guarantee that the programs will be compiled in the sequence I've specified based on priority. This has led to some runtime errors in my program.
I realized that in the ld file, when initializing dynamic arrays, there's no assurance of initializing init_array.* before init_array. This has resulted in runtime errors in the program. Consequently, I've rearranged the init_array.* in the ld file of NuttX to be placed before init_array and added a SORT operation to init_array.* to ensure accurate initialization based on priorities during linking.
Summary:
Keeping this option out of depend on any common serial.
Using the option, need to implement xxx_lowputc.S/c.
You can also logging the booting message through rewriting
fake arm64_lowputc with other debug method (eg semihosting,
ARM debug channel etc).
Signed-off-by: qinwei1 <qinwei1@xiaomi.com>
Summary:
Adding virtual evaluate platform FVP. This FVP board configuration
will be used to emulate generic ARM64v8-R (Cotex-R82)series hardware
platform and provide support for these devices:
- GICv3 interrupt controllers for ARMv8-r
- PL011 UART controller(FVP)
Note:
1. ostest is PASSED at fvp ( single core and SMP)
2. the FVP tools can be download from ARM site, please check FVP
board readme.txt
TODO: merge PL011 UART driver to common place
Signed-off-by: qinwei1 <qinwei1@xiaomi.com>