Commit 814b58e1 authored by Jean-Philippe Brucker's avatar Jean-Philippe Brucker Committed by Zheng Zengkai
Browse files

PCI: Support ats-supported device-tree property 

maillist inclusion
category: feature
bugzilla: 51855
CVE: NA

Reference: https://jpbrucker.net/git/linux/commit/?h=sva/2021-03-01&id=0e93ed439f6957d7ff821107c16f8dd8e7df0a2c



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

Device-tree declare whether a PCI root-complex supports ATS by setting
the "ats-supported" property. Copy this flag into device fwspec to let
IOMMU drivers quickly check if they can enable ATS for a device.

Signed-off-by: default avatarJean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: default avatarLijun Fang <fanglijun3@huawei.com>
Reviewed-by: default avatarWeilong Chen <chenweilong@huawei.com>
Signed-off-by: default avatarZheng Zengkai <zhengzengkai@huawei.com>
parent 415ccda7

drivers/iommu/of_iommu.c

+10 −0
Original line number Diff line number Diff line
@@ -175,6 +175,14 @@ static int of_iommu_configure_device(struct device_node *master_np, 
		      of_iommu_configure_dev(master_np, dev);

}



static void of_pci_check_device_ats(struct device *dev, struct device_node *np)

{

	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);



	if (fwspec && of_property_read_bool(np, "ats-supported"))

		fwspec->flags |= IOMMU_FWSPEC_PCI_RC_ATS;

}



const struct iommu_ops *of_iommu_configure(struct device *dev,

					   struct device_node *master_np,

					   const u32 *id)
@@ -208,6 +216,8 @@ const struct iommu_ops *of_iommu_configure(struct device *dev, 
		pci_request_acs();

		err = pci_for_each_dma_alias(to_pci_dev(dev),

					     of_pci_iommu_init, &info);

		of_pci_check_device_ats(dev, master_np);



	} else {

		err = of_iommu_configure_device(master_np, dev, id);

	}