Hi folks, In the t6000/t6001 (M1 Pro / Max) SoCs, Apple introduced a new version of their interrupt controller. This is a significant departure from AICv1 and seems designed to better scale to larger chips. This series adds support for it to the existing AIC driver. Gone are CPU affinities; instead there seems to be some kind of "automagic" dispatch to willing CPU cores, and cores can also opt-out via an IMP-DEF sysreg (!). Right now the bootloader just sets up all cores to accept IRQs, and we ignore all this and let the magic algorithm pick a CPU to accept the IRQ. In the future, we might start making use of these finer-grained capabilities for e.g. better real-time guarantees (CPUs running RT threads might opt out of IRQs). Legacy IPI support is also gone, so this implements Fast IPI support. Fast IPIs are implemented entirely in the CPU core complexes, using FIQs and IMP-DEF sysregs. This is also supported on t8103/M1, so we enable it there too, but we keep the legacy AIC IPI codepath in case it is useful for backporting to older chips. This also adds support for multi-die AIC2 controllers. While no multi-die products exist yet, the AIC2 in t600x is built to support up to 2 dies, and it's pretty clear how it works, so let's implement it. If we're lucky, when multi-die products roll around, this will let us support them with only DT changes. In order to support the extra die dimension, this introduces a 4-argument IRQ phandle form (3-argument is always supported and just implies die 0). All register offsets are computed based on capability register values, which should allow forward-compatibility with future AIC2 variants... except for one. For some inexplicable reason, the number of actually implemented die register sets is nowhere to be found (t600x has 2, but claims 1 die in use and 8 dies max, neither of which is what we need), and this is necessary to compute the event register offset, which is page-aligned after the die register sets. We have no choice but to stick this offset in the device tree... which is the same thing Apple do in their ADT. Hector Martin (6): dt-bindings: interrupt-controller: apple,aic: Add apple,aic2 support irqchip/apple-aic: Add Fast IPI support irqchip/apple-aic: Switch to irq_domain_create_tree and sparse hwirqs irqchip/apple-aic: Dynamically compute register offsets irqchip/apple-aic: Support multiple dies irqchip/apple-aic: Add support for AICv2 .../interrupt-controller/apple,aic.yaml | 62 ++- drivers/irqchip/irq-apple-aic.c | 419 ++++++++++++++---- 2 files changed, 393 insertions(+), 88 deletions(-) -- 2.33.0
