INTERRUPT MANAGEMENT FOR THE V3D ENGINE(9)

✨ Interrupt management for the V3D engine ✨

okay bestie, welcome to section 9 of the Kernel API Manual — this is the V3D engine interrupt-management page, and it’s lowkey iconic 💅. No cap, it’s all about how the driver handles interrupts from the V3D engine.

So here’s the register tea ☕: we have an interrupt status register (V3D_INTCTL) which reports interrupts, and where writing 1 bits clears those interrupts. There are also a pair of interrupt registers (V3D_INTENA/V3D_INTDIS) where writing a 1 to their bits enables or disables that specific interrupt, and 0s written are ignored — reading either one returns the set of enabled interrupts. periodt. 🫶

Here’s what we do for each interrupt vibe, in order:

• When we take a binning flush done interrupt, we need to submit the next frame for binning and move the finished frame to the render thread. 🎀
• When we take a render frame interrupt, we need to wake the processes waiting for some frame to be done, and get the next frame submitted ASAP (so the hardware doesn’t sit idle when there’s work to do). 🔥
• When we take the binner out of memory interrupt, we need to allocate some new memory and pass it to the binner so that the current job can make progress. 🌸

👀 SEE ALSO 👀

Kernel file: ./drivers/gpu/drm/vc4/vc4_irq.c

🎀 cute little sign-off, bestie: source/version is ./drivers/gpu/drm/vc4, the date is October 2026, and the footer title is Interrupt m...e V3D engine(9). byeee 💜