Remove master device from the IOMMU. This will be helpful when removing the
overlay nodes using dynamic programming during run time.
Signed-off-by: Vikram Garhwal <vikram.garh...@amd.com>
Reviewed-by: Michal Orzel <michal.or...@amd.com>
---
xen/drivers/passthrough/device_tree.c | 41 +++++++++++++++++++++++++++
xen/include/xen/iommu.h | 2 ++
2 files changed, 43 insertions(+)
diff --git a/xen/drivers/passthrough/device_tree.c
b/xen/drivers/passthrough/device_tree.c
index f3867ef1a6..46f9080c8f 100644
--- a/xen/drivers/passthrough/device_tree.c
+++ b/xen/drivers/passthrough/device_tree.c
@@ -125,6 +125,47 @@ int iommu_release_dt_devices(struct domain *d)
return 0;
}
+int iommu_remove_dt_device(struct dt_device_node *np)
+{
+ const struct iommu_ops *ops = iommu_get_ops();
+ struct device *dev = dt_to_dev(np);
+ int rc;
+
+ if ( !ops )
+ return -EOPNOTSUPP;
+
+ spin_lock(&dtdevs_lock);
+
+ if ( iommu_dt_device_is_assigned_locked(np) )
+ {
+ rc = -EBUSY;
+ goto fail;
+ }
+
+ /*
+ * The driver which supports generic IOMMU DT bindings must have this
+ * callback implemented.
+ */
+ if ( !ops->remove_device )
+ {
+ rc = -EOPNOTSUPP;
+ goto fail;
+ }
+
+ /*
+ * Remove master device from the IOMMU if latter is present and available.
+ * The driver is responsible for removing is_protected flag.
+ */
+ rc = ops->remove_device(0, dev);
+
+ if ( !rc )
+ iommu_fwspec_free(dev);
+
+fail:
+ spin_unlock(&dtdevs_lock);
+ return rc;
+}
+
int iommu_add_dt_device(struct dt_device_node *np)
{
const struct iommu_ops *ops = iommu_get_ops();
diff --git a/xen/include/xen/iommu.h b/xen/include/xen/iommu.h
index 76add226ec..6ba8d73966 100644
--- a/xen/include/xen/iommu.h
+++ b/xen/include/xen/iommu.h
@@ -219,6 +219,8 @@ int iommu_deassign_dt_device(struct domain *d, struct
dt_device_node *dev);
int iommu_dt_domain_init(struct domain *d);
int iommu_release_dt_devices(struct domain *d);
+int iommu_remove_dt_device(struct dt_device_node *np);
+
/*
* Helper to add master device to the IOMMU using generic IOMMU DT bindings.
*
--
2.17.1
