[RFC,v5,4/5] powerpc/iommu: Set IOMMU_GROUP_CAP_ISOLATE_MSIX

Submitted by Alexey Kardashevskiy on Aug. 7, 2017, 7:25 a.m.

Details

Message ID 20170807072548.3023-5-aik@ozlabs.ru
State New
Headers show

Commit Message

Alexey Kardashevskiy Aug. 7, 2017, 7:25 a.m.
This sets IOMMU_GROUP_CAP_ISOLATE_MSIX to a group unconditionally as
there is no IOMMU-capable hardware without such a feature.

On IBM POWERPC (POWER8) [1], PCI host bridge maintains BFDN-to-PE
translation (PE stands for "partitionable endpoint"), and PE index is used
to look at Interrupt Vector Table (IVT) to identify the interrupt server.
Without these translations in place, MSIX messages won't pass PHB.

[1] 3.2.4. MSI Design
http://openpowerfoundation.org/wp-content/uploads/resources/IODA2Spec/IODA2WGSpec-1.0.0-20160217.pdf

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
---
 arch/powerpc/kernel/iommu.c | 1 +
 1 file changed, 1 insertion(+)

Patch hide | download patch | download mbox

diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c
index 233ca3fe4754..dca0a83f1560 100644
--- a/arch/powerpc/kernel/iommu.c
+++ b/arch/powerpc/kernel/iommu.c
@@ -936,6 +936,7 @@  void iommu_register_group(struct iommu_table_group *table_group,
 	if (!name)
 		return;
 	iommu_group_set_name(grp, name);
+	iommu_group_set_caps(grp, 0, IOMMU_GROUP_CAP_ISOLATE_MSIX);
 	kfree(name);
 }