diff --git a/arch/sparc/kernel/pci.c b/arch/sparc/kernel/pci.c
index badf095..4606dc1 100644
--- a/arch/sparc/kernel/pci.c
+++ b/arch/sparc/kernel/pci.c
@@ -654,12 +654,12 @@ struct pci_bus *pci_scan_one_pbm(struct pci_pbm_info *pbm,
 	printk("PCI: Scanning PBM %s\n", node->full_name);
 
 	pci_add_resource_offset(&resources, &pbm->io_space,
-				pbm->io_space.start);
+				pbm->io_offset);
 	pci_add_resource_offset(&resources, &pbm->mem_space,
-				pbm->mem_space.start);
+				pbm->mem_offset);
 	if (pbm->mem64_space.flags)
 		pci_add_resource_offset(&resources, &pbm->mem64_space,
-					pbm->mem_space.start);
+					pbm->mem64_offset);
 	pbm->busn.start = pbm->pci_first_busno;
 	pbm->busn.end	= pbm->pci_last_busno;
 	pbm->busn.flags	= IORESOURCE_BUS;
@@ -733,30 +733,32 @@ int pcibios_enable_device(struct pci_dev *dev, int mask)
 static int __pci_mmap_make_offset_bus(struct pci_dev *pdev, struct vm_area_struct *vma,
 				      enum pci_mmap_state mmap_state)
 {
-	struct pci_pbm_info *pbm = pdev->dev.archdata.host_controller;
-	unsigned long space_size, user_offset, user_size;
-
-	if (mmap_state == pci_mmap_io) {
-		space_size = resource_size(&pbm->io_space);
-	} else {
-		space_size = resource_size(&pbm->mem_space);
-	}
+	unsigned long user_offset, user_size;
+	struct resource res, *root_bus_res;
+	struct pci_bus_region region;
+	struct pci_bus *bus;
 
 	/* Make sure the request is in range. */
 	user_offset = vma->vm_pgoff << PAGE_SHIFT;
 	user_size = vma->vm_end - vma->vm_start;
 
-	if (user_offset >= space_size ||
-	    (user_offset + user_size) > space_size)
+	region.start = user_offset;
+	region.end = user_offset + user_size - 1;
+	memset(&res, 0, sizeof(res));
+	if (mmap_state == pci_mmap_io)
+		res.flags = IORESOURCE_IO;
+	else
+		res.flags = IORESOURCE_MEM;
+
+	pcibios_bus_to_resource(pdev->bus, &res, &region);
+	bus = pdev->bus;
+	while (bus->parent)
+		bus = bus->parent;
+	root_bus_res = pci_find_bus_resource(bus, &res);
+	if (!root_bus_res)
 		return -EINVAL;
 
-	if (mmap_state == pci_mmap_io) {
-		vma->vm_pgoff = (pbm->io_space.start +
-				 user_offset) >> PAGE_SHIFT;
-	} else {
-		vma->vm_pgoff = (pbm->mem_space.start +
-				 user_offset) >> PAGE_SHIFT;
-	}
+	vma->vm_pgoff = res.start >> PAGE_SHIFT;
 
 	return 0;
 }
@@ -977,16 +979,12 @@ void pci_resource_to_user(const struct pci_dev *pdev, int bar,
 			  const struct resource *rp, resource_size_t *start,
 			  resource_size_t *end)
 {
-	struct pci_pbm_info *pbm = pdev->dev.archdata.host_controller;
-	unsigned long offset;
+	struct pci_bus_region region;
 
-	if (rp->flags & IORESOURCE_IO)
-		offset = pbm->io_space.start;
-	else
-		offset = pbm->mem_space.start;
+	pcibios_resource_to_bus(pdev->bus, &region, (struct resource *)rp);
 
-	*start = rp->start - offset;
-	*end = rp->end - offset;
+	*start = region.start;
+	*end = region.end;
 }
 
 void pcibios_set_master(struct pci_dev *dev)
diff --git a/arch/sparc/kernel/pci_common.c b/arch/sparc/kernel/pci_common.c
index 33524c1..76998f8 100644
--- a/arch/sparc/kernel/pci_common.c
+++ b/arch/sparc/kernel/pci_common.c
@@ -410,13 +410,16 @@ void pci_determine_mem_io_space(struct pci_pbm_info *pbm)
 
 	for (i = 0; i < num_pbm_ranges; i++) {
 		const struct linux_prom_pci_ranges *pr = &pbm_ranges[i];
-		unsigned long a, size;
+		unsigned long a, size, region_a;
 		u32 parent_phys_hi, parent_phys_lo;
+		u32 child_phys_mid, child_phys_lo;
 		u32 size_hi, size_lo;
 		int type;
 
 		parent_phys_hi = pr->parent_phys_hi;
 		parent_phys_lo = pr->parent_phys_lo;
+		child_phys_mid = pr->child_phys_mid;
+		child_phys_lo = pr->child_phys_lo;
 		if (tlb_type == hypervisor)
 			parent_phys_hi &= 0x0fffffff;
 
@@ -426,6 +429,8 @@ void pci_determine_mem_io_space(struct pci_pbm_info *pbm)
 		type = (pr->child_phys_hi >> 24) & 0x3;
 		a = (((unsigned long)parent_phys_hi << 32UL) |
 		     ((unsigned long)parent_phys_lo  <<  0UL));
+		region_a = (((unsigned long)child_phys_mid << 32UL) |
+		     ((unsigned long)child_phys_lo  <<  0UL));
 		size = (((unsigned long)size_hi << 32UL) |
 			((unsigned long)size_lo  <<  0UL));
 
@@ -440,6 +445,7 @@ void pci_determine_mem_io_space(struct pci_pbm_info *pbm)
 			pbm->io_space.start = a;
 			pbm->io_space.end = a + size - 1UL;
 			pbm->io_space.flags = IORESOURCE_IO;
+			pbm->io_offset = a - region_a;
 			saw_io = 1;
 			break;
 
@@ -448,6 +454,7 @@ void pci_determine_mem_io_space(struct pci_pbm_info *pbm)
 			pbm->mem_space.start = a;
 			pbm->mem_space.end = a + size - 1UL;
 			pbm->mem_space.flags = IORESOURCE_MEM;
+			pbm->mem_offset = a - region_a;
 			saw_mem = 1;
 			break;
 
@@ -456,6 +463,7 @@ void pci_determine_mem_io_space(struct pci_pbm_info *pbm)
 			pbm->mem64_space.start = a;
 			pbm->mem64_space.end = a + size - 1UL;
 			pbm->mem64_space.flags = IORESOURCE_MEM;
+			pbm->mem64_offset = a - region_a;
 			saw_mem = 1;
 			break;
 
@@ -471,14 +479,22 @@ void pci_determine_mem_io_space(struct pci_pbm_info *pbm)
 		prom_halt();
 	}
 
-	printk("%s: PCI IO[%llx] MEM[%llx]",
-	       pbm->name,
-	       pbm->io_space.start,
-	       pbm->mem_space.start);
+	if (pbm->io_space.flags)
+		printk("%s: PCI IO %pR offset %llx\n",
+		       pbm->name, &pbm->io_space, pbm->io_offset);
+	if (pbm->mem_space.flags)
+		printk("%s: PCI MEM %pR offset %llx\n",
+		       pbm->name, &pbm->mem_space, pbm->mem_offset);
+	if (pbm->mem64_space.flags && pbm->mem_space.flags) {
+		if (pbm->mem64_space.start <= pbm->mem_space.end)
+			pbm->mem64_space.start = pbm->mem_space.end + 1;
+		if (pbm->mem64_space.start > pbm->mem64_space.end)
+			pbm->mem64_space.flags = 0;
+	}
+
 	if (pbm->mem64_space.flags)
-		printk(" MEM64[%llx]",
-		       pbm->mem64_space.start);
-	printk("\n");
+		printk("%s: PCI MEM64 %pR offset %llx\n",
+		       pbm->name, &pbm->mem64_space, pbm->mem64_offset);
 
 	pbm->io_space.name = pbm->mem_space.name = pbm->name;
 	pbm->mem64_space.name = pbm->name;
diff --git a/arch/sparc/kernel/pci_impl.h b/arch/sparc/kernel/pci_impl.h
index 37222ca..2853af7 100644
--- a/arch/sparc/kernel/pci_impl.h
+++ b/arch/sparc/kernel/pci_impl.h
@@ -99,6 +99,10 @@ struct pci_pbm_info {
 	struct resource			mem_space;
 	struct resource			mem64_space;
 	struct resource			busn;
+	/* offset */
+	resource_size_t			io_offset;
+	resource_size_t			mem_offset;
+	resource_size_t			mem64_offset;
 
 	/* Base of PCI Config space, can be per-PBM or shared. */
 	unsigned long			config_space;
