[PATCH 4.17 217/324] gpu: host1x: Skip IOMMU initialization if firewall is enabled

From: Greg Kroah-Hartman
Date: Thu Aug 23 2018 - 04:59:37 EST


4.17-stable review patch. If anyone has any objections, please let me know.

------------------

From: Dmitry Osipenko <digetx@xxxxxxxxx>

[ Upstream commit 4466b1f0e022f94a026bd700fee34bff15cdc4ef ]

Host1x's CDMA can't access the command buffers if IOMMU and Host1x
firewall are enabled in the kernels config because firewall doesn't map
the copied buffer into IOVA space. Fix this by skipping IOMMU
initialization if firewall is enabled as firewall merges sparse cmdbufs
into a single contiguous buffer and hence IOMMU isn't needed in this case.

Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/host1x/dev.c | 3 +++
1 file changed, 3 insertions(+)

--- a/drivers/gpu/host1x/dev.c
+++ b/drivers/gpu/host1x/dev.c
@@ -218,6 +218,9 @@ static int host1x_probe(struct platform_
return err;
}

+ if (IS_ENABLED(CONFIG_TEGRA_HOST1X_FIREWALL))
+ goto skip_iommu;
+
host->group = iommu_group_get(&pdev->dev);
if (host->group) {
struct iommu_domain_geometry *geometry;