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Message-ID: <a4e66e61-35c4-adb5-fb65-e1f076bbe6ba@collabora.com>
Date:   Fri, 18 Feb 2022 09:41:37 +0100
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Subject: Re: [PATCH 2/2] iommu/mediatek: Add mt8186 iommu support
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To:     Yong Wu <yong.wu@mediatek.com>
Cc:     Robin Murphy <robin.murphy@arm.com>,
        Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>,
        Tomasz Figa <tfiga@chromium.org>,
        linux-mediatek@lists.infradead.org, srv_heupstream@mediatek.com,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        iommu@lists.linux-foundation.org,
        Hsin-Yi Wang <hsinyi@chromium.org>, youlin.pei@mediatek.com,
        anan.sun@mediatek.com, xueqi.zhang@mediatek.com,
        yen-chang.chen@mediatek.com, mingyuan.ma@mediatek.com,
        yf.wang@mediatek.com, libo.kang@mediatek.com,
        chengci.xu@mediatek.com, Joerg Roedel <joro@8bytes.org>,
        Rob Herring <robh+dt@kernel.org>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        Will Deacon <will@kernel.org>
References: <20220125093244.18230-1-yong.wu@mediatek.com>
 <20220125093244.18230-3-yong.wu@mediatek.com>
 <b52a1df8-58f4-baa2-cfb6-9c56244caa0f@collabora.com>
 <01cc69cdf7773962140c01fe37b12ab2c9491c25.camel@mediatek.com>
 <0e430d1e-ee25-1b3d-4a2c-8641db255adb@collabora.com>
 <8b63983222a4a304586a7b880379fcf4a7036c4a.camel@mediatek.com>
From:   AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>
In-Reply-To: <8b63983222a4a304586a7b880379fcf4a7036c4a.camel@mediatek.com>
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Il 18/02/22 04:32, Yong Wu ha scritto:
> On Mon, 2022-01-31 at 10:25 +0100, AngeloGioacchino Del Regno wrote:
>> Il 28/01/22 10:39, Yong Wu ha scritto:
>>> On Thu, 2022-01-27 at 12:28 +0100, AngeloGioacchino Del Regno
>>> wrote:
>>>> Il 25/01/22 10:32, Yong Wu ha scritto:
>>>>> Add mt8186 iommu supports.
>>>>>
>>>>> Signed-off-by: Anan Sun <anan.sun@mediatek.com>
>>>>> Signed-off-by: Yong Wu <yong.wu@mediatek.com>
>>>>> ---
>>>>>     drivers/iommu/mtk_iommu.c | 17 +++++++++++++++++
>>>>>     1 file changed, 17 insertions(+)
>>>
>>> [snip]
>>>
>>>>>     static const struct mtk_iommu_plat_data mt8192_data = {
>>>>>     	.m4u_plat       = M4U_MT8192,
>>>>>     	.flags          = HAS_BCLK | HAS_SUB_COMM_2BITS |
>>>>> OUT_ORDER_WR_EN |
>>>>> @@ -1470,6 +1486,7 @@ static const struct of_device_id
>>>>> mtk_iommu_of_ids[] = {
>>>>>     	{ .compatible = "mediatek,mt8167-m4u", .data =
>>>>> &mt8167_data},
>>>>>     	{ .compatible = "mediatek,mt8173-m4u", .data =
>>>>> &mt8173_data},
>>>>>     	{ .compatible = "mediatek,mt8183-m4u", .data =
>>>>> &mt8183_data},
>>>>> +	{ .compatible = "mediatek,mt8186-iommu-mm", .data =
>>>>> &mt8186_data_mm},
>>>>
>>>> Hello!
>>>>
>>>> Is there any particular reason why this compatible is not
>>>> "mediatek,mt8186-m4u"?
>>>
>>> There is no special reason. In the previous SoC, We only support MM
>>> IOMMU, it was called by "m4u". In the lastest SoC, We have the
>>> other
>>> types IOMMU, like for INFRA masters and APU, thus they are called
>>> "mm
>>> iommu", "infra iommu" and "apu iommu". Of course, "m4u" means "mm
>>> iommu".
>>>
>>
>> I suggest, at this point, to change it to "mediatek,mt8186-m4u" for
>> naming
>> consistency with the other bindings and to avoid any kind of
>> confusion.
> 
> Understand. But we don't call it "m4u" anymore. I'd not like to use a
> outdated name. For readable, I could add a comment like this:
> 
> { .compatible = "mediatek,mt8186-iommu-mm", xx}, /* iommu-mm: m4u */
> 
> Is this ok for you?
> Thanks.
> 

Ok, go on with that.

Cheers,
Angelo

>> Thank you!
>>
>>>>
>>>> Thanks,
>>>> Angelo
>>>>
>>>>>     	{ .compatible = "mediatek,mt8192-m4u", .data =
>>>>> &mt8192_data},
>>>>>     	{ .compatible = "mediatek,mt8195-iommu-infra", .data =
>>>>> &mt8195_data_infra},
>>>>>     	{ .compatible = "mediatek,mt8195-iommu-vdo",   .data =
>>>>> &mt8195_data_vdo},
>>>>
>>>> _______________________________________________
>>>> Linux-mediatek mailing list
>>>> Linux-mediatek@lists.infradead.org
>>>> http://lists.infradead.org/mailman/listinfo/linux-mediatek
>>
>>
>