Subject: Re: [PATCH v2 3/5] iommu/mediatek: Remove the power status checking
 in tlb flush all
To:     Dafna Hirschfeld <dafna.hirschfeld@collabora.com>,
        iommu@lists.linux-foundation.org, Yong Wu <yong.wu@mediatek.com>,
        Joerg Roedel <joro@8bytes.org>, Will Deacon <will@kernel.org>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        "moderated list:MEDIATEK IOMMU DRIVER" 
        <linux-mediatek@lists.infradead.org>,
        "moderated list:ARM/Mediatek SoC support" 
        <linux-arm-kernel@lists.infradead.org>,
        open list <linux-kernel@vger.kernel.org>, kernel@collabora.com,
        linux-media@vger.kernel.org, sebastian.reichel@collabora.com
References: <20211208120744.2415-1-dafna.hirschfeld@collabora.com>
 <20211208120744.2415-4-dafna.hirschfeld@collabora.com>
From:   AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>
Message-ID: <10ca4eae-2959-a697-6818-308e04f88e14@collabora.com>
Date:   Mon, 10 Jan 2022 12:43:46 +0100
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Il 08/12/21 13:07, Dafna Hirschfeld ha scritto:
> From: Yong Wu <yong.wu@mediatek.com>
> 
> To simplify the code, Remove the power status checking in the
> tlb_flush_all, remove this:
>     if (pm_runtime_get_if_in_use(data->dev) <= 0)
> 	    continue;
> 
> The mtk_iommu_tlb_flush_all is called from
> a) isr
> b) tlb flush range fail case
> c) iommu_create_device_direct_mappings
> 
> In first two cases, the power and clock are always enabled.
> In the third case tlb flush is unnecessary because in a later patch
> in the series a full flush from the pm_runtime_resume callback is added.
> 
> In addition, writing the tlb control register when the iommu is not resumed
> is ok and the write is ignored.
> 
> Signed-off-by: Yong Wu <yong.wu@mediatek.com>
> [refactor commit log]
> Signed-off-by: Dafna Hirschfeld <dafna.hirschfeld@collabora.com>

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>