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Date:   Tue, 12 Sep 2023 11:18:20 +0100
From:   Will Deacon <will@kernel.org>
To:     Mukesh Ojha <quic_mojha@quicinc.com>
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Subject: Re: [REBASE PATCH v5 08/17] arm64: mm: Add dynamic ramoops region
 support through command line
Message-ID: <20230912101820.GA10884@willie-the-truck>
References: <1694429639-21484-1-git-send-email-quic_mojha@quicinc.com>
 <1694429639-21484-9-git-send-email-quic_mojha@quicinc.com>
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On Mon, Sep 11, 2023 at 04:23:50PM +0530, Mukesh Ojha wrote:
> The reserved memory region for ramoops is assumed to be at a fixed
> and known location when read from the devicetree. This may not be
> required for something like Qualcomm's minidump which is interested
> in knowing addresses of ramoops region but it does not put hard
> requirement of address being fixed as most of it's SoC does not
> support warm reset and does not use pstorefs at all instead it has
> firmware way of collecting ramoops region if it gets to know the
> address and register it with apss minidump table which is sitting
> in shared memory region in DDR and firmware will have access to
> these table during reset and collects it on crash of SoC.
> 
> So, add the support of reserving ramoops region to be dynamically
> allocated early during boot if it is request through command line
> via 'dyn_ramoops_size=' and fill up reserved resource structure and
> export the structure, so that it can be read by ramoops driver.
> 
> Signed-off-by: Mukesh Ojha <quic_mojha@quicinc.com>
> ---
>  arch/arm64/mm/init.c       | 94 ++++++++++++++++++++++++++++++++++++++++++++++

Why does this need to be in the arch code? There's absolutely nothing
arm64-specific here.

Will