Intel IOMMU Suspend/Resume Support - Interrupt Remapping
This patch enables suspend/resume for interrupt remapping. During suspend,
interrupt remapping is disabled. When resume, interrupt remapping is enabled
again.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/pci/intr_remapping.c b/drivers/pci/intr_remapping.c
index b041a40..c26633d 100644
--- a/drivers/pci/intr_remapping.c
+++ b/drivers/pci/intr_remapping.c
@@ -470,7 +470,7 @@
/*
* Disable Interrupt Remapping.
*/
-static void disable_intr_remapping(struct intel_iommu *iommu)
+static void iommu_disable_intr_remapping(struct intel_iommu *iommu)
{
unsigned long flags;
u32 sts;
@@ -478,6 +478,12 @@
if (!ecap_ir_support(iommu->ecap))
return;
+ /*
+ * global invalidation of interrupt entry cache before disabling
+ * interrupt-remapping.
+ */
+ qi_global_iec(iommu);
+
spin_lock_irqsave(&iommu->register_lock, flags);
sts = dmar_readq(iommu->reg + DMAR_GSTS_REG);
@@ -511,7 +517,7 @@
* Disable intr remapping and queued invalidation, if already
* enabled prior to OS handover.
*/
- disable_intr_remapping(iommu);
+ iommu_disable_intr_remapping(iommu);
dmar_disable_qi(iommu);
}
@@ -639,3 +645,54 @@
return ir_supported;
}
+
+void disable_intr_remapping(void)
+{
+ struct dmar_drhd_unit *drhd;
+ struct intel_iommu *iommu = NULL;
+
+ /*
+ * Disable Interrupt-remapping for all the DRHD's now.
+ */
+ for_each_iommu(iommu, drhd) {
+ if (!ecap_ir_support(iommu->ecap))
+ continue;
+
+ iommu_disable_intr_remapping(iommu);
+ }
+}
+
+int reenable_intr_remapping(int eim)
+{
+ struct dmar_drhd_unit *drhd;
+ int setup = 0;
+ struct intel_iommu *iommu = NULL;
+
+ for_each_iommu(iommu, drhd)
+ if (iommu->qi)
+ dmar_reenable_qi(iommu);
+
+ /*
+ * Setup Interrupt-remapping for all the DRHD's now.
+ */
+ for_each_iommu(iommu, drhd) {
+ if (!ecap_ir_support(iommu->ecap))
+ continue;
+
+ /* Set up interrupt remapping for iommu.*/
+ iommu_set_intr_remapping(iommu, eim);
+ setup = 1;
+ }
+
+ if (!setup)
+ goto error;
+
+ return 0;
+
+error:
+ /*
+ * handle error condition gracefully here!
+ */
+ return -1;
+}
+