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Date:   Fri, 23 Oct 2020 12:21:49 +0100
From:   Will Deacon <will@kernel.org>
To:     Yong Wu <yong.wu@mediatek.com>
Cc:     Joerg Roedel <joro@8bytes.org>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        Rob Herring <robh+dt@kernel.org>,
        Robin Murphy <robin.murphy@arm.com>,
        Krzysztof Kozlowski <krzk@kernel.org>,
        Evan Green <evgreen@chromium.org>,
        Tomasz Figa <tfiga@google.com>,
        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, youlin.pei@mediatek.com,
        Nicolas Boichat <drinkcat@chromium.org>, anan.sun@mediatek.com,
        chao.hao@mediatek.com, ming-fan.chen@mediatek.com,
        Greg Kroah-Hartman <gregkh@google.com>, kernel-team@android.com
Subject: Re: [PATCH v3 11/24] iommu/io-pgtable-arm-v7s: Quad lvl1 pgtable for
 MediaTek
Message-ID: <20201023112148.GB20933@willie-the-truck>
References: <20200930070647.10188-1-yong.wu@mediatek.com>
 <20200930070647.10188-12-yong.wu@mediatek.com>
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On Wed, Sep 30, 2020 at 03:06:34PM +0800, Yong Wu wrote:
> The standard input iova bits is 32. MediaTek quad the lvl1 pagetable
> (4 * lvl1). No change for lvl2 pagetable. Then the iova bits can reach
> 34bit.
> 
> Signed-off-by: Yong Wu <yong.wu@mediatek.com>
> ---
>  drivers/iommu/io-pgtable-arm-v7s.c | 13 ++++++++++---
>  drivers/iommu/mtk_iommu.c          |  2 +-
>  2 files changed, 11 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/iommu/io-pgtable-arm-v7s.c b/drivers/iommu/io-pgtable-arm-v7s.c
> index 8362fdf76657..306bae2755ed 100644
> --- a/drivers/iommu/io-pgtable-arm-v7s.c
> +++ b/drivers/iommu/io-pgtable-arm-v7s.c
> @@ -50,10 +50,17 @@
>   */
>  #define ARM_V7S_ADDR_BITS		32

If we rename this to _ARM_V7S_ADDR_BITS can we then have ARM_V7S_ADDR_BITS
take a cfg parameter and move the arm_v7s_is_mtk_enabled() check in there?
Same for _ARM_V7S_LVL_BITS.

That would avoid scattering arm_v7s_is_mtk_enabled() into all the users.

Will