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Date: Mon, 29 Apr 2024 07:34:05 +0530
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Subject: Re: [PATCH] arm64/sysreg: Update ID_AA64MMFR2_EL1 register
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To: Mark Brown <broonie@kernel.org>, Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org, catalin.marinas@arm.com,
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References: <20240419021325.2880384-1-anshuman.khandual@arm.com>
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 <ZidEalY_V3bXhJrJ@finisterre.sirena.org.uk>
From: Anshuman Khandual <anshuman.khandual@arm.com>
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On 4/23/24 10:47, Mark Brown wrote:
> On Mon, Apr 22, 2024 at 06:16:13PM +0100, Will Deacon wrote:
>> On Mon, Apr 22, 2024 at 08:38:40AM +0530, Anshuman Khandual wrote:
> 
>>> This is not being used currently but will be required for upcoming
>>> features. I was under the impression that register fields (atleast
>>> for the ID registers) should be kept updated, with latest released
>>> spec ? Besides lately arch/arm64/tools/sysreg serves as very good
>>> reference for all necessary register fields.
> 
>> Why? The linux headers aren't documenting the architecture.
> 
> I don't know that it's something that we should be doing apropos of
> nothing but if people have done updates and they're not unreasonbly
> complicated to review it does seem useful to integrate them to avoid
> duplicated work.  There have been some issues with that around the ID
> registers (which are going to be on the places most prone to this I
> guess).

The other problem is by not updating the individual register fields with
the latest spec, it also gives an wrong impression about that field, and
also might create confusion.