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Date:   Wed, 19 Feb 2020 11:09:13 +0100
From:   Joerg Roedel <joro@8bytes.org>
To:     Kai-Heng Feng <kai.heng.feng@canonical.com>
Cc:     Alex Deucher <alexander.deucher@amd.com>,
        "open list:AMD IOMMU (AMD-VI)" <iommu@lists.linux-foundation.org>,
        open list <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v3] iommu/amd: Disable IOMMU on Stoney Ridge systems
Message-ID: <20200219100913.GA1961@8bytes.org>
References: <20200210075115.14838-1-kai.heng.feng@canonical.com>
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On Mon, Feb 10, 2020 at 03:51:15PM +0800, Kai-Heng Feng wrote:
> Serious screen flickering when Stoney Ridge outputs to a 4K monitor.
> 
> Use identity-mapping and PCI ATS doesn't help this issue.
> 
> According to Alex Deucher, IOMMU isn't enabled on Windows, so let's do
> the same here to avoid screen flickering on 4K monitor.
> 
> Cc: Alex Deucher <alexander.deucher@amd.com>
> Bug: https://gitlab.freedesktop.org/drm/amd/issues/961
> Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>

Applied, thanks.