Re: [PATCH v4 01/10] dt-bindings: irq: sun6i-r: Split the binding from sun7i-nmi

[Rob Herring]

On Mon, 11 Jan 2021 23:59:41 -0600, Samuel Holland wrote:
> The R_INTC in the A31 and newer sun8i/sun50i SoCs has additional
> functionality compared to the sun7i/sun9i NMI controller. Among other
> things, it multiplexes access to up to 128 interrupts corresponding to
> (and in parallel to) the first 128 GIC SPIs. This means the NMI is no
> longer the lowest-numbered hwirq at this irqchip, since it is SPI 32 or
> 96 (depending on SoC). hwirq 0 now corresponds to SPI 0, usually UART0.
> 
> To allow access to all multiplexed IRQs, the R_INTC requires a new
> binding where the interrupt number matches the GIC interrupt number.
> Otherwise, interrupts with hwirq numbers below the NMI would not be
> representable in the device tree.
> 
> For simplicity, copy the three-cell GIC binding; this disambiguates
> interrupt 0 in the old binding (the NMI) from interrupt 0 in the new
> binding (SPI 0) by the number of cells.
> 
> Because the H6 R_INTC has a different mapping from multiplexed IRQs to
> top-level register bits, it is no longer compatible with the A31 R_INTC.
> 
> Signed-off-by: Samuel Holland <samuel@xxxxxxxxxxxx>
> ---
>  .../allwinner,sun6i-a31-r-intc.yaml           | 66 +++++++++++++++++++
>  .../allwinner,sun7i-a20-sc-nmi.yaml           | 10 ---
>  2 files changed, 66 insertions(+), 10 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/interrupt-controller/allwinner,sun6i-a31-r-intc.yaml
> 

Reviewed-by: Rob Herring <robh@xxxxxxxxxx>