linux-kernel - Re: [PATCH 1/6] dt-bindings: interrupt-controller: apple,aic: Add apple,aic2 support

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <fbb54509-c32c-ecc9-53d3-664168699e17@marcan.st>
Date:   Sat, 11 Dec 2021 21:52:05 +0900
From:   Hector Martin <marcan@...can.st>
To:     Marc Zyngier <maz@...nel.org>
Cc:     Rob Herring <robh@...nel.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        Sven Peter <sven@...npeter.dev>,
        Alyssa Rosenzweig <alyssa@...enzweig.io>,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        devicetree@...r.kernel.org
Subject: Re: [PATCH 1/6] dt-bindings: interrupt-controller: apple,aic: Add
 apple,aic2 support

On 11/12/2021 21.44, Marc Zyngier wrote:
> On Sat, 11 Dec 2021 12:28:10 +0000,
> Hector Martin <marcan@...can.st> wrote:
>>
>> On 10/12/2021 02.28, Rob Herring wrote:
>>> On Thu, Dec 09, 2021 at 01:32:44PM +0900, Hector Martin wrote:
>> <snip>
>>>> +  - if:
>>>> +      properties:
>>>> +        compatible:
>>>> +          contains:
>>>> +            enum:
>>>> +              - apple,aic2
>>>> +    then:
>>>> +      required:
>>>> +        - apple,event-reg
>>>
>>> Is this property valid for aic1? If not, you need:
>>>
>>> else:
>>>     not:
>>>       required:
>>>         - apple,event-reg
>>>
>>
>> Thanks, I wasn't sure how to do this. Took me a second to realize how
>> the logic works here, heh.
>>
>>>
>>> I tend to think you should just make this a separate document. There's
>>> not a whole lot of sharing (compared to any other interrupt controller).
>>
>> Good point. I just kind of defaulted to this way because the driver is
>> the same (and does share a bunch), but indeed the binding doesn't
>> really reflect any of that. I'll split it off into another document
>> for v2. Might as well make the 4-argument interrupt form mandatory
>> then (we use it for all DTs, even the current 1-die machines, on AICv2
>> SoCs; the driver can handle both but we might as well be stricter with
>> the binding).
> 
> Well, I'm about to add this 4th cell for FIQ signalled interrupts so
> that we can specify an affinity (similarly to what we do with GICv3, 0
> meaning no specific affinity and a non-zero phandle indicating a
> specific affinity).
> 
> Generalising the 4-cell even on AICv1 systems would be pretty nice,
> and we can always keep the backward compat as a fallback for old DTs
> (that'd pretty cheap).

The driver still takes both, so that's not an issue; we can certainly 
have the AICv1 binding allow both and the AICv2 one require the 4-cell 
form. That will also make copy/paste between t8103 and t6000 SoCs 
slightly less error-prone, since both will have the extra cell.

-- 
Hector Martin (marcan@...can.st)
Public Key: https://mrcn.st/pub