Lots of baremetal is about booting the VC4 and then switching the ARM on and doing stuff on the ARM.
OpenCL on VC4 has got me thinking about the GPU/QPU
Has anyone blinked a GPIO LED with QPU code?
Activity led is initially under VPU control on boot?
Been wondering if the QPU's could be used as real time controllers
Nanokernel's in QPU?
I have not seen QPU specific timers, VPU's have any?
I assume the ThreedX OS is running in one VPU after bootcode.bin is running.
This would leave the other VPU free, unless the ThreadX is running multicores