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Message-ID: <ea67da10-0e8d-47d1-992c-484977d152b6@gmail.com>
Date:   Tue, 5 Dec 2023 11:06:07 -0800
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Subject: Re: [PATCH 4/4] memory: brcmstb_dpfe: introduce best-effort API
 detection
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To:     Markus Mayer <mmayer@broadcom.com>,
        Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
        Florian Fainelli <florian.fainelli@broadcom.com>,
        Rob Herring <robh+dt@kernel.org>,
        Conor Dooley <conor+dt@kernel.org>
Cc:     Linux ARM Kernel List <linux-arm-kernel@lists.infradead.org>,
        Device Tree Mailing List <devicetree@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
References: <20231205184741.3092376-1-mmayer@broadcom.com>
 <20231205184741.3092376-5-mmayer@broadcom.com>
From:   Florian Fainelli <f.fainelli@gmail.com>
In-Reply-To: <20231205184741.3092376-5-mmayer@broadcom.com>
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On 12/5/23 10:47, Markus Mayer wrote:
> Add a best-effort probe function that tries all known DPFE versions to
> see if one might actually work. This helps in cases where device tree
> doesn't provide the proper version information for whatever reason. In
> that case, the driver may still be able to register if one of the known
> API versions ends up working.
> 
> Caveat: we have to skip "v1" during our best effort attempts. This is
> due to the fact that attempting a firmware download as required by v1
> will result in a memory access violation on anything but v1 hardware.
> This would crash the kernel. Since we don't know the HW version, we need
> to play it safe and skip v1.
> 
> Signed-off-by: Markus Mayer <mmayer@broadcom.com>

Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
-- 
Florian