Re: port-arm/57104: "intrctl affinity" does not function on Raspberry Pi 4 and other ARM boards

[Sad Clouds <cryintothebluesky%gmail.com@localhost>]

The following reply was made to PR port-arm/57104; it has been noted by GNATS.

From: Sad Clouds <cryintothebluesky%gmail.com@localhost>
To: Brad Spencer <brad%anduin.eldar.org@localhost>
Cc: gnats-bugs%netbsd.org@localhost, port-arm-maintainer%netbsd.org@localhost,
 gnats-admin%netbsd.org@localhost, netbsd-bugs%netbsd.org@localhost
Subject: Re: port-arm/57104: "intrctl affinity" does not function on
 Raspberry Pi 4 and other ARM boards
Date: Sat, 10 Dec 2022 17:29:48 +0000

 On Sat, 10 Dec 2022 11:38:20 -0500
 Brad Spencer <brad%anduin.eldar.org@localhost> wrote:
 
 > I think that this may be a hardware limitation of the RPI SOC.  If I
 > remember correctly the RPI can only deliver hard interrupts to CPU0.
 
 This post suggest that at least on Linux, interrupt affinity can be set
 for Raspberry Pi 4. You cannot pin one interrupt to multiple CPUs, but
 you can pin it to any one CPU, as long as it is one CPU per interrupt.
 
 https://tomcore.io/docs/articles/RaspberryPI/raspberry-pi-4b-network-performance/