Root complex node in IORT has a bit telling whether it supports ATS or
not. Store this bit in the IOMMU fwspec when setting up a device, so it
can be accessed later by an IOMMU driver.
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@xxxxxxx>
---
drivers/acpi/arm64/iort.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index c5fecf97ee2f..e7d2d156d78f 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -720,6 +720,14 @@ void iort_set_dma_mask(struct device *dev)
dev->dma_mask = &dev->coherent_dma_mask;
}
+static bool iort_pci_rc_supports_ats(struct acpi_iort_node *node)
+{
+ struct acpi_iort_root_complex *pci_rc;
+
+ pci_rc = (struct acpi_iort_root_complex *)node->node_data;
+ return pci_rc->ats_attribute & ACPI_IORT_ATS_SUPPORTED;
+}
+
/**
* iort_iommu_configure - Set-up IOMMU configuration for a device.
*
@@ -752,6 +760,8 @@ const struct iommu_ops *iort_iommu_configure(struct device *dev)
ops = iort_iommu_xlate(dev, parent, streamid);
+ if (!IS_ERR_OR_NULL(ops) && iort_pci_rc_supports_ats(node))
+ dev->iommu_fwspec->flags |= IOMMU_FWSPEC_PCI_RC_SUPPORTS_ATS;
} else {
int i = 0;
--
2.12.1
