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littlekernel / lk

LK embedded kernel
MIT License
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arm_gic: GICv3 support? #242

Open lecopzer opened 5 years ago

lecopzer commented 5 years ago

Hello, I have a question about ARM GIC:

Do lk need GICv3 support in dev/interrupt/arm_gic ?

Or we have to init GICv3 in ATF before load lk loaded as S-EL1 OS and not to init GICv3 in lk?

mu578 commented 5 years ago

reference missing:

https://static.docs.arm.com/dai0492/b/GICv3_Software_Overview_Official_Release_B.pdf

lecopzer commented 5 years ago

Thanks a lot for reference. But I wonder whether the GICv3 init should be done inside lk or have to depends on ATF

Thanks for reply

mu578 commented 5 years ago

my 2 cents in lk; going to sleep.

travisg commented 5 years ago

Indeed, GICv3 support is needed the moment it is brought up on a GIC v3 based machine. Can be tested on qemu if told to emulate V3.

GICv3 is pretty close to 2, but different enough that it's worth making a copy of the v2 driver and modifying it.

travisg commented 5 years ago

We made a gicv3 driver for zircon, so probably simpler to just back port it from there.