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Date:   Mon, 24 Apr 2023 09:03:35 +0200
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Subject: Re: [PATCH 2/5] arm64: dts: mediatek: cherry: Assign dp-intf aliases
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To:     Chen-Yu Tsai <wenst@chromium.org>
Cc:     matthias.bgg@gmail.com, robh+dt@kernel.org,
        krzysztof.kozlowski+dt@linaro.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-mediatek@lists.infradead.org, kernel@collabora.com
References: <20230420094433.42794-1-angelogioacchino.delregno@collabora.com>
 <20230420094433.42794-3-angelogioacchino.delregno@collabora.com>
 <CAGXv+5EtCdpXtq6q2Cv+QAZPUE6yJiSZhngSc0sftz-_uDrZXw@mail.gmail.com>
From:   AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>
In-Reply-To: <CAGXv+5EtCdpXtq6q2Cv+QAZPUE6yJiSZhngSc0sftz-_uDrZXw@mail.gmail.com>
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Il 21/04/23 08:46, Chen-Yu Tsai ha scritto:
> On Thu, Apr 20, 2023 at 5:45 PM AngeloGioacchino Del Regno
> <angelogioacchino.delregno@collabora.com> wrote:
>>
>> On Cherry boards, the IP at 0x1c015000 (dp_intf0) is used as primary
>> dp-intf, while the other at 0x1c113000 (dp_intf1) is used as secondary:
>> assign them to dp-intf{0,1} aliases respectively.
>>
>> Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
>> ---
>>   arch/arm64/boot/dts/mediatek/mt8195-cherry.dtsi | 2 ++
> 
> This should be applied at the SoC level. The display pipeline is fixed in
> MMSYS, so it applies to all MT8195 devices.
> 

It's fixed in the MMSYS configuration/driver but - as far as I remember (I can
recheck on the datasheets) - the dp_intfX function can be inverted meaning that
the MMSYS paths can be configured such that DP_INTF0 becomes secondary and the
other becomes primary: this is why I am putting that into mt8195-cherry and not
mt8195.dtsi.

Regards,
Angelo

>>   1 file changed, 2 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/mediatek/mt8195-cherry.dtsi b/arch/arm64/boot/dts/mediatek/mt8195-cherry.dtsi
>> index 0820e9ba3829..918380697a9a 100644
>> --- a/arch/arm64/boot/dts/mediatek/mt8195-cherry.dtsi
>> +++ b/arch/arm64/boot/dts/mediatek/mt8195-cherry.dtsi
>> @@ -10,6 +10,8 @@
>>
>>   / {
>>          aliases {
>> +               dp-intf0 = &dp_intf0;
>> +               dp-intf1 = &dp_intf1;
>>                  i2c0 = &i2c0;
>>                  i2c1 = &i2c1;
>>                  i2c2 = &i2c2;
>> --
>> 2.40.0
>>
>>
>