Message-ID: <88a3fa09-60cb-bb3c-c392-286efd983627@collabora.com>
Date:   Wed, 22 Feb 2023 10:13:45 +0100
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Subject: Re: [PATCH v2 06/10] dt-bindings: gpu: mali-bifrost: Add a compatible
 for MediaTek MT8186
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To:     Chen-Yu Tsai <wenst@chromium.org>
Cc:     airlied@gmail.com, daniel@ffwll.ch, robh+dt@kernel.org,
        krzysztof.kozlowski+dt@linaro.org, steven.price@arm.com,
        alyssa.rosenzweig@collabora.com, matthias.bgg@gmail.com,
        robh@kernel.org, dri-devel@lists.freedesktop.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        linux-mediatek@lists.infradead.org
References: <20230221153740.1620529-1-angelogioacchino.delregno@collabora.com>
 <20230221153740.1620529-7-angelogioacchino.delregno@collabora.com>
 <CAGXv+5Ed-5Nq0zNzCGzez3fnW2yxW7zFx9B6k58Y4yb8P+hvpw@mail.gmail.com>
From:   AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>
In-Reply-To: <CAGXv+5Ed-5Nq0zNzCGzez3fnW2yxW7zFx9B6k58Y4yb8P+hvpw@mail.gmail.com>
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Il 22/02/23 09:37, Chen-Yu Tsai ha scritto:
> On Tue, Feb 21, 2023 at 11:37 PM AngeloGioacchino Del Regno
> <angelogioacchino.delregno@collabora.com> wrote:
>>
>> Get GPU support on MT8186 by adding its compatible.
>>
>> Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
>> ---
>>   Documentation/devicetree/bindings/gpu/arm,mali-bifrost.yaml | 5 +++++
>>   1 file changed, 5 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/gpu/arm,mali-bifrost.yaml b/Documentation/devicetree/bindings/gpu/arm,mali-bifrost.yaml
>> index be18b161959b..43a841d4e94d 100644
>> --- a/Documentation/devicetree/bindings/gpu/arm,mali-bifrost.yaml
>> +++ b/Documentation/devicetree/bindings/gpu/arm,mali-bifrost.yaml
>> @@ -15,6 +15,11 @@ properties:
>>
>>     compatible:
>>       oneOf:
>> +      - items:
>> +          - enum:
>> +              - mediatek,mt8186-mali
>> +          - const: mediatek,mt8183b-mali
>> +          - const: arm,mali-bifrost # Mali Bifrost GPU model/revision is fully discoverable
> 
> The MT8186 has Mali-G52 MC2 2EE, while the MT8183 has Mali-G72 MP3.

Keeping in mind the obvious - which is that G52 and G72 are both Bifrost....

> So we actually need a new entry with two power domains.
> 

...This is my node for MT8186:

		gpu: gpu@13040000 {
			compatible = "mediatek,mt8186-mali",
				     "mediatek,mt8183b-mali",
				     "arm,mali-bifrost";
			reg = <0 0x13040000 0 0x4000>;

			clocks = <&mfgsys CLK_MFG_BG3D>;
			interrupts = <GIC_SPI 276 IRQ_TYPE_LEVEL_HIGH 0>,
				     <GIC_SPI 275 IRQ_TYPE_LEVEL_HIGH 0>,
				     <GIC_SPI 274 IRQ_TYPE_LEVEL_HIGH 0>;
			interrupt-names = "job", "mmu", "gpu";
			power-domains = <&spm MT8186_POWER_DOMAIN_MFG1>,
					<&spm MT8186_POWER_DOMAIN_MFG2>,
					<&spm MT8186_POWER_DOMAIN_MFG3>;
			power-domain-names = "core0", "core1", "core2";

			/* Please ignore speedbin, that's for another time :-) */
			nvmem-cells = <&gpu_volt_bin>;
			nvmem-cell-names = "speed-bin";
			#cooling-cells = <2>;
		};

There are three MFG power domains... MFG2 and MFG3 are parents of MFG1, on that
I agree, but we can avoid adding a new entry just for MT8186 and use the MT8183-b
one while still being technically correct.

Besides, Mali G52 and Mali G72 are both Bifrost... so I don't think that this
commit is incorrect. For the sake of simplicity, I would push on getting this
one picked.

Unless there are any real-strong opinions against...

Regards,
Angelo

> Our downstream Mali driver & DT use just that.
> 
> ChenYu