On 30/04/2019 16:02, Rob Herring wrote: > On Tue, Apr 30, 2019 at 7:13 AM Geert Uytterhoeven > <geert+renesas@xxxxxxxxx> wrote: >> >> Add DT bindings for the Renesas RZ/A1 Interrupt Controller. >> >> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx> >> --- >> v2: >> - Add "renesas,gic-spi-base", >> - Document RZ/A2M. >> --- >> .../renesas,rza1-irqc.txt | 30 +++++++++++++++++++ >> 1 file changed, 30 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/interrupt-controller/renesas,rza1-irqc.txt >> >> diff --git a/Documentation/devicetree/bindings/interrupt-controller/renesas,rza1-irqc.txt b/Documentation/devicetree/bindings/interrupt-controller/renesas,rza1-irqc.txt >> new file mode 100644 >> index 0000000000000000..ea8ddb6955338ccd >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/interrupt-controller/renesas,rza1-irqc.txt >> @@ -0,0 +1,30 @@ >> +DT bindings for the Renesas RZ/A1 Interrupt Controller >> + >> +The RZ/A1 Interrupt Controller is a front-end for the GIC found on Renesas >> +RZ/A1 and RZ/A2 SoCs: >> + - IRQ sense select for 8 external interrupts, 1:1-mapped to 8 GIC SPI >> + interrupts, >> + - NMI edge select. >> + >> +Required properties: >> + - compatible: Must be "renesas,<soctype>-irqc", and "renesas,rza1-irqc" as >> + fallback. >> + Examples with soctypes are: >> + - "renesas,r7s72100-irqc" (RZ/A1H) >> + - "renesas,r7s9210-irqc" (RZ/A2M) >> + - #interrupt-cells: Must be 2 (an interrupt index and flags, as defined >> + in interrupts.txt in this directory) >> + - interrupt-controller: Marks the device as an interrupt controller >> + - reg: Base address and length of the memory resource used by the interrupt >> + controller >> + - renesas,gic-spi-base: Lowest GIC SPI interrupt number this block maps to. > > Why isn't this just an 'interrupts' property? That's likely because of kernel limitations. The DT code does an of_populate() on any device that it finds, parse the "interrupts" propertiy, resulting in the irq_descs being populated. That creates havoc, as these interrupts are not for this device, but for something that is connected to it. This is merely a bridge of some sort. Furthermore, this is a rather long established practice: gic-v2m, gic-v3-mbi, mediatek,sysirq, mediatek,cirq... All the bits of glue that for one reason or another plug onto the GIC use the same method. > Plus, without 'interrupts' walking the hierarchy is broken. Erm... Which hierarchy? Thanks, M. -- Jazz is not dead. It just smells funny...
