On 2022-09-21 11:17, Krzysztof Kozlowski wrote:

On 21/09/2022 12:14, Robin Murphy wrote:

quoted

quoted

+#define SOC_PERIPHERAL_IRQ_NUMBER(na)  (na + 32)
+#define SOC_PERIPHERAL_IRQ(nr, na) GIC_SPI nr SOC_PERIPHERAL_IRQ_NUMBER(na)
   / {
          compatible = "renesas,r9a07g043";
          #address-cells = <2>;

@@ -128,7 +130,7 @@ ssi1: ssi@1004a000 {
                          compatible = "renesas,r9a07g043-ssi",
                                       "renesas,rz-ssi";
                          reg = <0 0x1004a000 0 0x400>;
-                       interrupts = <GIC_SPI 330 IRQ_TYPE_LEVEL_HIGH>,
+                       interrupts = <SOC_PERIPHERAL_IRQ(330, IRQ_TYPE_LEVEL_HIGH)>,

Or any other method like that....

Which will generate the text:

	"interrupts = <GIC_SPI 330 (IRQ_TYPE_LEVEL_HIGH + 32)>,"

(give or take some whitespace)

CPP supports constant expressions in #if and #elif directives, but
macros are purely literal text replacement. It might technically be
achievable with some insane CPP metaprogramming, but for all practical
purposes this is a non-starter unless dtc itself grows the ability to
process arithmetic expressions.

Except I put it into flags, not to IRQ number, it works, so I am not
sure why do you call it non-starter?

Oh, it seems dtc *does* understand arithmetic already, that's what I was 
missing.

$ echo "/dts-v1/;/{foo = <(2 + 3)>;};" | dtc -Odts
/dts-v1/;

/ {
         foo = <0x05>;
};

Thanks for teaching me something new!

Robin.