RE: [PATCH] sh: Avoid using IRQ0 on SH3 and SH4

From: David Laight
Date: Wed Jul 12 2023 - 04:12:18 EST


From: John Paul Adrian Glaubitz
> Sent: 09 July 2023 00:13
....
> Looking at arch/sh/boards/mach-r2d/irq.c, there is some IRQ translation going
> on and maybe that's the part where we need to correct the offset by 16?

Would it be less problematic to use (say) 16 for IRQ_0
leaving IRQ_1+ as 1+ ?

At least that would only cause issues for code that needed
to use IRQ_0.

(It has to be said that making IRQ 0 invalid seemed wrong
to me. x86 (IBM PC) gets away with it because IRQ 0 is
always assigned to platform specific hardware.)

David

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