[PATCH 4/4 Xenial SRU] powerpc/pseries: Fix PCI config address for DDW

[Tim Gardner]

From: Gavin Shan <gwshan at linux.vnet.ibm.com>

BugLink: http://bugs.launchpad.net/bugs/1599250

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")
Cc: stable at vger.kernel.org # v3.4+
Reported-by: Guilherme G. Piccoli <gpiccoli at linux.vnet.ibm.com>
Signed-off-by: Gavin Shan <gwshan at linux.vnet.ibm.com>
Tested-by: Guilherme G. Piccoli <gpiccoli at linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
(cherry picked from commit 8a934efe94347eee843aeea65bdec8077a79e259)
Signed-off-by: Tim Gardner <tim.gardner at canonical.com>
---
 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 b7dfc13..3e8865b 100644
--- a/arch/powerpc/platforms/pseries/iommu.c
+++ b/arch/powerpc/platforms/pseries/iommu.c
@@ -927,7 +927,7 @@ 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));
@@ -956,7 +956,7 @@ 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) */
-- 
1.9.1