How does #PinePhone handle Arm64 Interrupts? Let's find out ... With a little help from Apache #NuttX RTOS

https://lupyuen.github.io/articles/interrupt?1

#PinePhone Interrupts are complicated ... That's why we need a Generic Interrupt Controller to handle them

https://lupyuen.github.io/articles/interrupt?2#generic-interrupt-controller

Generic Interrupt Controller in #PinePhone is particularly problematic ... It was created 11 years ago for 32-bit Arm CPUs!

https://lupyuen.github.io/articles/interrupt?3#allwinner-a64-gic

Finding the Generic Interrupt Controller on #PinePhone

https://lupyuen.github.io/articles/interrupt?3#allwinner-a64-gic

#NuttX RTOS supports Generic Interrupt Controller version 2 ... We hacked it to run on #PinePhone

https://lupyuen.github.io/articles/interrupt?4#gic-version-2

#NuttX's Generic Interrupt Controller for Arm32 ... Seems to run on #PinePhone with a few tweaks

https://lupyuen.github.io/articles/interrupt?4#gic-version-2

Let's test our Generic Interrupt Controller on #QEMU ... Before running on #PinePhone

https://lupyuen.github.io/articles/interrupt?5#test-pinephone-gic-with-qemu

Dumping the #QEMU Device Tree ... Reveals the address of Generic Interrupt Controller

https://lupyuen.github.io/articles/interrupt?5#test-pinephone-gic-with-qemu

Why did the System Timer freeze #PinePhone? Let's find out!

https://lupyuen.github.io/articles/interrupt?6#pinephone-hangs-at-startup

Troubleshooting the Timer Interrupt on #PinePhone

https://lupyuen.github.io/articles/interrupt?7#timer-interrupt-isnt-handled

Inside the Arm64 Vector Table on #PinePhone

https://lupyuen.github.io/articles/interrupt?8#arm64-vector-table-is-wrong

Checking our Arm64 Vector Table on #PinePhone ... Yep it's wrong! 🙄

https://lupyuen.github.io/articles/interrupt?8#arm64-vector-table-is-wrong

What's an Arm64 Exception Level ... And why it matters for #PinePhone Interrupts

https://lupyuen.github.io/articles/interrupt?9#exception-levels