Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Feedback-ID: i51094778:Fastmail
User-Agent: Cyrus-JMAP/3.7.0-alpha0-1185-g841157300a-fm-20221208.002-g84115730
Mime-Version: 1.0
Message-Id: <bfee5a64-bb7c-43ee-a2ca-7e13421508f4@app.fastmail.com>
In-Reply-To: <fd66fa48-8810-5b8b-c330-8456bdb9de9e@marcan.st>
References: <20230104110013.24738-1-marcan@marcan.st>
 <20230104110013.24738-8-marcan@marcan.st>
 <bebc741d-bcbe-4449-9379-be70fd65b0f0@app.fastmail.com>
 <fd66fa48-8810-5b8b-c330-8456bdb9de9e@marcan.st>
Date:   Thu, 05 Jan 2023 10:45:29 +0100
From:   "Sven Peter" <sven@svenpeter.dev>
To:     "Hector Martin" <marcan@marcan.st>,
        "Joerg Roedel" <joro@8bytes.org>, "Will Deacon" <will@kernel.org>,
        "Robin Murphy" <robin.murphy@arm.com>
Cc:     "Alyssa Rosenzweig" <alyssa@rosenzweig.io>,
        "Janne Grunau" <j@jannau.net>, "Rob Herring" <robh+dt@kernel.org>,
        "Krzysztof Kozlowski" <krzysztof.kozlowski+dt@linaro.org>,
        devicetree@vger.kernel.org, iommu@lists.linux.dev,
        asahi@lists.linux.dev, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 7/7] iommu: dart: Add t8110 DART support
Content-Type: text/plain
Precedence: bulk

Hi,

On Thu, Jan 5, 2023, at 06:19, Hector Martin wrote:
> On 2023/01/04 22:50, Sven Peter wrote:
>> Do you have any more details on this registers? For the 8103 DART
>> we called it _CONFIG but I assume for the t8110 DART it can
>> actually lock different parts of the HW instead of just a global lock?
>
> This is based on R's reverse engineering here:
>
> https://github.com/AsahiLinux/m1n1/blob/main/proxyclient/m1n1/hw/dart8110.py#L87
>
> I don't think they ever fully nailed down exactly what the lock bit
> behavior is, though.

Fair enough, I was mostly curious if it was actually _PROTECT and not just
_CONFIG with different bit assignments. Sounds like it does mostly set up
protections though.


Sven