Some platforms may support ACPI name-space enumerated devices
that are capable of generating DMA requests. Platforms which
support DMA remapping explicitly declares any such DMA-capable
ACPI name-space devices in the platform through ACPI Name-space
Device Declaration (ANDD) structure and enumerate them through
the Device Scope of the appropriate remapping hardware unit.
Signed-off-by: Lu Baolu <baolu...@linux.intel.com>
---
drivers/iommu/intel-iommu.c | 45 +++++++++++++++++++++++++++++++++++++
1 file changed, 45 insertions(+)
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index b7f5a6390be6..7f9cf9188f5f 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -4816,6 +4816,48 @@ static int __init platform_optin_force_iommu(void)
return 1;
}
+static int __init probe_acpi_namespace_devices(void)
+{
+ struct dmar_drhd_unit *drhd;
+ struct intel_iommu *iommu;
+ struct device *dev;
+ int i, ret = 0;
+
+ for_each_active_iommu(iommu, drhd) {
+ for_each_active_dev_scope(drhd->devices,
+ drhd->devices_cnt, i, dev) {
+ struct acpi_device_physical_node *pn;
+ struct iommu_group *group;
+ struct acpi_device *adev;
+
+ if (dev->bus != &acpi_bus_type)
+ continue;
+
+ adev = to_acpi_device(dev);
+ mutex_lock(&adev->physical_node_lock);
+ list_for_each_entry(pn,
+ &adev->physical_node_list, node) {
+ group = iommu_group_get(pn->dev);
+ if (group) {
+ iommu_group_put(group);
+ continue;
+ }
+
+ pn->dev->bus->iommu_ops = &intel_iommu_ops;
+ ret = iommu_probe_device(pn->dev);
+ if (ret)
+ break;
+ }
+ mutex_unlock(&adev->physical_node_lock);
+
+ if (ret)
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
int __init intel_iommu_init(void)
{
int ret = -ENODEV;
@@ -4928,6 +4970,9 @@ int __init intel_iommu_init(void)
cpuhp_setup_state(CPUHP_IOMMU_INTEL_DEAD, "iommu/intel:dead", NULL,
intel_iommu_cpu_dead);
+ if (probe_acpi_namespace_devices())
+ pr_warn("ACPI name space devices didn't probe correctly\n");
+
/* Finally, we enable the DMA remapping hardware. */
for_each_iommu(iommu, drhd) {
if (!translation_pre_enabled(iommu))
--
2.17.1
