linux-kernel - Re: [Patch V2] memory: tegra: Remove clients SID override programming

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Message-ID: <cf5422a7-351a-6780-ff7f-e20bc81f94c7@linaro.org>
Date:   Tue, 22 Nov 2022 12:14:34 +0100
From:   Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>
To:     Ashish Mhetre <amhetre@...dia.com>, thierry.reding@...il.com,
        jonathanh@...dia.com, dmitry.osipenko@...labora.com,
        linux-kernel@...r.kernel.org, linux-tegra@...r.kernel.org
Subject: Re: [Patch V2] memory: tegra: Remove clients SID override programming

On 22/11/2022 06:31, Ashish Mhetre wrote:
> On newer Tegra releases, early boot SID override programming and SID
> override programming during resume is handled by bootloader.
> Also, SID override is programmed on-demand during probe_finalize() call
> of IOMMU which is done in tegra186_mc_client_sid_override() in this same
> file. This function does it more correctly by checking if write is
> permitted on SID override register. It also checks if SID override
> register is already written with correct value and skips re-writing it
> in that case.
> Hence, removing the SID override programming of all clients.
> 
> Fixes: 393d66fd2cac ("memory: tegra: Implement SID override programming")

I could not get from commit msg what is the bug being fixed. You just
said "more correctly", but usually things are either correct or not.
What are visible effects of the bug?

Otherwise it sounds more like optimization or a bit better approach, but
not a bugfix.

Best regards,
Krzysztof