[PATCH kernel] powerpc/powernv/ioda2: Add devices only from buses which belong to PE

Alexey Kardashevskiy
2015-06-12T06:21:40Z

The existing code puts all devices from a root PE to the same IOMMU group.
However it is a possible situation when subordinate buses belong to
separate PEs, in this case devices from these subordinate buses
should be added to lower level PE rather to the root PE.

This limits pnv_ioda_setup_bus_dma() invocation to only PEs which own
all subordinate buses.

Suggested-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
---

This would be nice to have together with the DDW patchset.
This does not fix anything DDW patchset did, it fixes IOMMU
groups management which is essential for the whole feature to work.

---
arch/powerpc/platforms/powernv/pci-ioda.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index a0b00c1..3b1dc79 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -1702,7 +1702,7 @@ static void pnv_ioda_setup_bus_dma(struct pnv_ioda_pe *pe,
set_iommu_table_base(&dev->dev, pe->table_group.tables[0]);
iommu_add_device(&dev->dev);

- if (dev->subordinate)
+ if ((pe->flags & PNV_IODA_PE_BUS_ALL) && dev->subordinate)
pnv_ioda_setup_bus_dma(pe, dev->subordinate);
}
}
--
2.4.0.rc3.8.gfb3e7d5