Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org,
        Matias Zuniga <matias.nicolas.zc@gmail.com>,
        Thierry Reding <treding@nvidia.com>,
        Dmitry Osipenko <digetx@gmail.com>,
        Krzysztof Kozlowski <krzk@kernel.org>
Subject: [PATCH 5.9 353/391] memory: tegra: Remove GPU from DRM IOMMU group
Date:   Tue,  3 Nov 2020 21:36:44 +0100
Message-Id: <20201103203410.956450253@linuxfoundation.org>
In-Reply-To: <20201103203348.153465465@linuxfoundation.org>
References: <20201103203348.153465465@linuxfoundation.org>
User-Agent: quilt/0.66
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Thierry Reding <treding@nvidia.com>

commit ea90f66f2a8629dde07328df0b8314aae5e54a47 upstream.

Commit 63a613fdb16c ("memory: tegra: Add gr2d and gr3d to DRM IOMMU
group") added the GPU to the DRM IOMMU group, which doesn't make any
sense. This causes problems when Nouveau tries to attach to the SMMU
and causes it to fall back to using the DMA API.

Remove the GPU from the DRM groups to restore the old behaviour. The
GPU should always have its own IOMMU domain to make sure it can map
buffers into contiguous chunks (for big page support) without getting
in the way of mappings from the DRM group.

Cc: <stable@vger.kernel.org>
Fixes: 63a613fdb16c ("memory: tegra: Add gr2d and gr3d to DRM IOMMU group")
Reported-by: Matias Zuniga <matias.nicolas.zc@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20200901153248.1831263-1-thierry.reding@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/memory/tegra/tegra124.c |    1 -
 1 file changed, 1 deletion(-)

--- a/drivers/memory/tegra/tegra124.c
+++ b/drivers/memory/tegra/tegra124.c
@@ -957,7 +957,6 @@ static const struct tegra_smmu_swgroup t
 static const unsigned int tegra124_group_drm[] = {
 	TEGRA_SWGROUP_DC,
 	TEGRA_SWGROUP_DCB,
-	TEGRA_SWGROUP_GPU,
 	TEGRA_SWGROUP_VIC,
 };