From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Move code for processing DT IOMMU specifier to a separate helper.
This helper will be re-used for adding PCI devices by the subsequent
patches as we will need exact the same actions for processing
DT PCI-IOMMU specifier.
While at it introduce NO_IOMMU to avoid magic "1".
Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Signed-off-by: Stewart Hildebrand <stewart.hildebrand@amd.com>
Signed-off-by: Mykyta Poturai <mykyta_poturai@epam.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
---
v6->v7:
* explained NO_IOMMU in comments
v5->v6:
* pass ops parameter to iommu_dt_xlate()
* add Julien's R-b
v4->v5:
* rebase on top of "dynamic node programming using overlay dtbo" series
* move #define NO_IOMMU 1 to header
* s/these/this/ inside comment
v3->v4:
* make dt_phandle_args *iommu_spec const
* move !ops->add_device check to helper
v2->v3:
* no change
v1->v2:
* no change
downstream->v1:
* trivial rebase
* s/dt_iommu_xlate/iommu_dt_xlate/
(cherry picked from commit c26bab0415ca303df86aba1d06ef8edc713734d3 from
the downstream branch poc/pci-passthrough from
https://gitlab.com/xen-project/people/bmarquis/xen-arm-poc.git)
---
xen/drivers/passthrough/device_tree.c | 48 +++++++++++++++++----------
xen/include/xen/iommu.h | 3 ++
2 files changed, 33 insertions(+), 18 deletions(-)
diff --git a/xen/drivers/passthrough/device_tree.c b/xen/drivers/passthrough/device_tree.c
index 075fb25a37..4c35281d98 100644
--- a/xen/drivers/passthrough/device_tree.c
+++ b/xen/drivers/passthrough/device_tree.c
@@ -137,6 +137,30 @@ int iommu_release_dt_devices(struct domain *d)
return 0;
}
+static int iommu_dt_xlate(struct device *dev,
+ const struct dt_phandle_args *iommu_spec,
+ const struct iommu_ops *ops)
+{
+ int rc;
+
+ if ( !ops->dt_xlate )
+ return -EINVAL;
+
+ if ( !dt_device_is_available(iommu_spec->np) )
+ return NO_IOMMU;
+
+ rc = iommu_fwspec_init(dev, &iommu_spec->np->dev);
+ if ( rc )
+ return rc;
+
+ /*
+ * Provide DT IOMMU specifier which describes the IOMMU master
+ * interfaces of that device (device IDs, etc) to the driver.
+ * The driver is responsible to decide how to interpret them.
+ */
+ return ops->dt_xlate(dev, iommu_spec);
+}
+
int iommu_remove_dt_device(struct dt_device_node *np)
{
const struct iommu_ops *ops = iommu_get_ops();
@@ -146,7 +170,7 @@ int iommu_remove_dt_device(struct dt_device_node *np)
ASSERT(rw_is_locked(&dt_host_lock));
if ( !iommu_enabled )
- return 1;
+ return NO_IOMMU;
if ( !ops )
return -EOPNOTSUPP;
@@ -187,12 +211,12 @@ int iommu_add_dt_device(struct dt_device_node *np)
const struct iommu_ops *ops = iommu_get_ops();
struct dt_phandle_args iommu_spec;
struct device *dev = dt_to_dev(np);
- int rc = 1, index = 0;
+ int rc = NO_IOMMU, index = 0;
ASSERT(system_state < SYS_STATE_active || rw_is_locked(&dt_host_lock));
if ( !iommu_enabled )
- return 1;
+ return NO_IOMMU;
if ( !ops )
return -EINVAL;
@@ -215,27 +239,15 @@ int iommu_add_dt_device(struct dt_device_node *np)
{
/*
* The driver which supports generic IOMMU DT bindings must have
- * these callback implemented.
+ * this callback implemented.
*/
- if ( !ops->add_device || !ops->dt_xlate )
+ if ( !ops->add_device )
{
rc = -EINVAL;
goto fail;
}
- if ( !dt_device_is_available(iommu_spec.np) )
- break;
-
- rc = iommu_fwspec_init(dev, &iommu_spec.np->dev);
- if ( rc )
- break;
-
- /*
- * Provide DT IOMMU specifier which describes the IOMMU master
- * interfaces of that device (device IDs, etc) to the driver.
- * The driver is responsible to decide how to interpret them.
- */
- rc = ops->dt_xlate(dev, &iommu_spec);
+ rc = iommu_dt_xlate(dev, &iommu_spec, ops);
if ( rc )
break;
diff --git a/xen/include/xen/iommu.h b/xen/include/xen/iommu.h
index b928c67e19..c3b8df9815 100644
--- a/xen/include/xen/iommu.h
+++ b/xen/include/xen/iommu.h
@@ -238,6 +238,9 @@ int iommu_do_dt_domctl(struct xen_domctl *domctl, struct domain *d,
*/
int iommu_remove_dt_device(struct dt_device_node *np);
+/* Error code for reporting no IOMMU is present */
+#define NO_IOMMU 1
+
#endif /* HAS_DEVICE_TREE */
struct page_info;
--
2.34.1