[PATCH 4.2.y-ckt 5/5] powerpc/pseries: Fix PCI config address for DDW

[Kamal Mostafa]

4.2.8-ckt13 -stable review patch.  If anyone has any objections, please let me know.

---8<------------------------------------------------------------

From: Gavin Shan <gwshan@xxxxxxxxxxxxxxxxxx>

commit 8a934efe94347eee843aeea65bdec8077a79e259 upstream.

In commit 8445a87f7092 "powerpc/iommu: Remove the dependency on EEH
struct in DDW mechanism", the PE address was replaced with the PCI
config address in order to remove dependency on EEH. According to PAPR
spec, firmware (pHyp or QEMU) should accept "xxBBSSxx" format PCI config
address, not "xxxxBBSS" provided by the patch. Note that "BB" is PCI bus
number and "SS" is the combination of slot and function number.

This fixes the PCI address passed to DDW RTAS calls.

Fixes: 8445a87f7092 ("powerpc/iommu: Remove the dependency on EEH struct in DDW mechanism")
Reported-by: Guilherme G. Piccoli <gpiccoli@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Gavin Shan <gwshan@xxxxxxxxxxxxxxxxxx>
Tested-by: Guilherme G. Piccoli <gpiccoli@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
 arch/powerpc/platforms/pseries/iommu.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c
index 34ee145..cd148c3 100644
--- a/arch/powerpc/platforms/pseries/iommu.c
+++ b/arch/powerpc/platforms/pseries/iommu.c
@@ -928,7 +928,7 @@ static int query_ddw(struct pci_dev *dev, const u32 *ddw_avail,
 	dn = pci_device_to_OF_node(dev);
 	pdn = PCI_DN(dn);
 	buid = pdn->phb->buid;
-	cfg_addr = (pdn->busno << 8) | pdn->devfn;
+	cfg_addr = ((pdn->busno << 16) | (pdn->devfn << 8));
 
 	ret = rtas_call(ddw_avail[0], 3, 5, (u32 *)query,
 		  cfg_addr, BUID_HI(buid), BUID_LO(buid));
@@ -957,7 +957,7 @@ static int create_ddw(struct pci_dev *dev, const u32 *ddw_avail,
 	dn = pci_device_to_OF_node(dev);
 	pdn = PCI_DN(dn);
 	buid = pdn->phb->buid;
-	cfg_addr = (pdn->busno << 8) | pdn->devfn;
+	cfg_addr = ((pdn->busno << 16) | (pdn->devfn << 8));
 
 	do {
 		/* extra outputs are LIOBN and dma-addr (hi, lo) */
-- 
2.7.4