[PATCH v3 03/19] iommu/tegra: gart: Ignore devices without IOMMU phandle in DT

From: Dmitry Osipenko <digetx@gmail.com>
To: Joerg Roedel <joro@8bytes.org>,
	Robin Murphy <robin.murphy@arm.com>,
	Thierry Reding <thierry.reding@gmail.com>,
	Jonathan Hunter <jonathanh@nvidia.com>,
	Rob Herring <robh+dt@kernel.org>
Cc: iommu@lists.linux-foundation.org, devicetree@vger.kernel.org,
	linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH v3 03/19] iommu/tegra: gart: Ignore devices without IOMMU phandle in DT
Date: Sat, 18 Aug 2018 18:54:14 +0300	[thread overview]
Message-ID: <20180818155430.5586-4-digetx@gmail.com> (raw)
In-Reply-To: <20180818155430.5586-1-digetx@gmail.com>

GART can't handle all devices, hence ignore devices that aren't related
to GART. IOMMU phandle must be explicitly assign to devices in the device
tree.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
 drivers/iommu/tegra-gart.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/tegra-gart.c b/drivers/iommu/tegra-gart.c
index e9524ed264cf..f6cf5cd5aaca 100644
--- a/drivers/iommu/tegra-gart.c
+++ b/drivers/iommu/tegra-gart.c
@@ -342,8 +342,12 @@ static bool gart_iommu_capable(enum iommu_cap cap)
 
 static int gart_iommu_add_device(struct device *dev)
 {
-	struct iommu_group *group = iommu_group_get_for_dev(dev);
+	struct iommu_group *group;
 
+	if (!dev->iommu_fwspec)
+		return -ENODEV;
+
+	group = iommu_group_get_for_dev(dev);
 	if (IS_ERR(group))
 		return PTR_ERR(group);
 
@@ -360,6 +364,12 @@ static void gart_iommu_remove_device(struct device *dev)
 	iommu_device_unlink(&gart_handle->iommu, dev);
 }
 
+static int gart_iommu_of_xlate(struct device *dev,
+			       struct of_phandle_args *args)
+{
+	return 0;
+}
+
 static const struct iommu_ops gart_iommu_ops = {
 	.capable	= gart_iommu_capable,
 	.domain_alloc	= gart_iommu_domain_alloc,
@@ -373,6 +383,7 @@ static const struct iommu_ops gart_iommu_ops = {
 	.unmap		= gart_iommu_unmap,
 	.iova_to_phys	= gart_iommu_iova_to_phys,
 	.pgsize_bitmap	= GART_IOMMU_PGSIZES,
+	.of_xlate	= gart_iommu_of_xlate,
 };
 
 static int tegra_gart_suspend(struct device *dev)
@@ -438,6 +449,7 @@ static int tegra_gart_probe(struct platform_device *pdev)
 	}
 
 	iommu_device_set_ops(&gart->iommu, &gart_iommu_ops);
+	iommu_device_set_fwnode(&gart->iommu, dev->fwnode);
 
 	ret = iommu_device_register(&gart->iommu);
 	if (ret) {
-- 
2.18.0

