Re: [PATCH RESEND 1/1] x86/of: Add support for boot time interrupt mode config

From: Andy Shevchenko
Date: Mon Nov 14 2022 - 04:44:58 EST


On Mon, Nov 14, 2022 at 05:20:06PM +0800, Rahul Tanwar wrote:
> Presently, init/boot time interrupt delivery mode is enumerated only
> for ACPI enabled systems by parsing MADT table or for older systems
> by parsing MP table. But for OF based x86 systems, it is assumed &
> fixed to legacy PIC mode.
>
> Add support for configuration of init time interrupt delivery mode for
> x86 OF based systems by introducing a new optional boolean property
> 'intel,no-imcr' for interrupt-controller node of local APIC. This
> property emulates IMCRP Bit 7 of MP feature info byte 2 of MP
> floating pointer structure.
>
> Defaults to legacy PIC mode if absent. Configures it to virtual wire
> compatibility mode if present.

...

> + if (of_property_read_bool(dn, "intel,no-imcr")) {

I can't find this property in the Documentation/devicetree/bindings.

Moreover, I prefer to see positive one, something like:

intel,virtual-wire-bla-bla-bla

Please consult with DT people on how properly name it.

> + pr_info(" Virtual Wire compatibility mode.\n");
> + pic_mode = 0;
> + } else {
> + pr_info(" IMCR and PIC compatibility mode.\n");
> + pic_mode = 1;
> + }

--
With Best Regards,
Andy Shevchenko