diff --git a/arch/powerpc/include/asm/pci-bridge.h b/arch/powerpc/include/asm/pci-bridge.h
index 0694f73..8b11b5b 100644
--- a/arch/powerpc/include/asm/pci-bridge.h
+++ b/arch/powerpc/include/asm/pci-bridge.h
@@ -39,11 +39,6 @@
 	resource_size_t io_base_phys;
 	resource_size_t pci_io_size;
 
-	/* Some machines (PReP) have a non 1:1 mapping of
-	 * the PCI memory space in the CPU bus space
-	 */
-	resource_size_t pci_mem_offset;
-
 	/* Some machines have a special region to forward the ISA
 	 * "memory" cycles such as VGA memory regions. Left to 0
 	 * if unsupported
@@ -86,6 +81,7 @@
 	 */
 	struct resource	io_resource;
 	struct resource mem_resources[3];
+	resource_size_t mem_offset[3];
 	int global_number;		/* PCI domain number */
 
 	resource_size_t dma_window_base_cur;
diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
index cf00588..f5c5c90 100644
--- a/arch/powerpc/kernel/pci-common.c
+++ b/arch/powerpc/kernel/pci-common.c
@@ -786,22 +786,8 @@
 				hose->isa_mem_size = size;
 			}
 
-			/* We get the PCI/Mem offset from the first range or
-			 * the, current one if the offset came from an ISA
-			 * hole. If they don't match, bugger.
-			 */
-			if (memno == 0 ||
-			    (isa_hole >= 0 && pci_addr != 0 &&
-			     hose->pci_mem_offset == isa_mb))
-				hose->pci_mem_offset = cpu_addr - pci_addr;
-			else if (pci_addr != 0 &&
-				 hose->pci_mem_offset != cpu_addr - pci_addr) {
-				printk(KERN_INFO
-				       " \\--> Skipped (offset mismatch) !\n");
-				continue;
-			}
-
 			/* Build resource */
+			hose->mem_offset[memno] = cpu_addr - pci_addr;
 			res = &hose->mem_resources[memno++];
 			res->flags = IORESOURCE_MEM;
 			if (pci_space & 0x40000000)
@@ -817,20 +803,6 @@
 			res->child = NULL;
 		}
 	}
-
-	/* If there's an ISA hole and the pci_mem_offset is -not- matching
-	 * the ISA hole offset, then we need to remove the ISA hole from
-	 * the resource list for that brige
-	 */
-	if (isa_hole >= 0 && hose->pci_mem_offset != isa_mb) {
-		unsigned int next = isa_hole + 1;
-		printk(KERN_INFO " Removing ISA hole at 0x%016llx\n", isa_mb);
-		if (next < memno)
-			memmove(&hose->mem_resources[isa_hole],
-				&hose->mem_resources[next],
-				sizeof(struct resource) * (memno - next));
-		hose->mem_resources[--memno].flags = 0;
-	}
 }
 
 /* Decide whether to display the domain number in /proc */
@@ -916,6 +888,7 @@
 	struct pci_controller *hose = pci_bus_to_host(bus);
 	struct pci_dev *dev = bus->self;
 	resource_size_t offset;
+	struct pci_bus_region region;
 	u16 command;
 	int i;
 
@@ -925,10 +898,10 @@
 
 	/* Job is a bit different between memory and IO */
 	if (res->flags & IORESOURCE_MEM) {
-		/* If the BAR is non-0 (res != pci_mem_offset) then it's probably been
-		 * initialized by somebody
-		 */
-		if (res->start != hose->pci_mem_offset)
+		pcibios_resource_to_bus(dev, &region, res);
+
+		/* If the BAR is non-0 then it's probably been initialized */
+		if (region.start != 0)
 			return 0;
 
 		/* The BAR is 0, let's check if memory decoding is enabled on
@@ -940,11 +913,11 @@
 
 		/* Memory decoding is enabled and the BAR is 0. If any of the bridge
 		 * resources covers that starting address (0 then it's good enough for
-		 * us for memory
+		 * us for memory space)
 		 */
 		for (i = 0; i < 3; i++) {
 			if ((hose->mem_resources[i].flags & IORESOURCE_MEM) &&
-			    hose->mem_resources[i].start == hose->pci_mem_offset)
+			    hose->mem_resources[i].start == hose->mem_offset[i])
 				return 0;
 		}
 
@@ -1381,10 +1354,9 @@
 
  no_io:
 	/* Check for memory */
-	offset = hose->pci_mem_offset;
-	pr_debug("hose mem offset: %016llx\n", (unsigned long long)offset);
 	for (i = 0; i < 3; i++) {
 		pres = &hose->mem_resources[i];
+		offset = hose->mem_offset[i];
 		if (!(pres->flags & IORESOURCE_MEM))
 			continue;
 		pr_debug("hose mem res: %pR\n", pres);
@@ -1524,6 +1496,7 @@
 					struct list_head *resources)
 {
 	struct resource *res;
+	resource_size_t offset;
 	int i;
 
 	/* Hookup PHB IO resource */
@@ -1533,51 +1506,37 @@
 		printk(KERN_WARNING "PCI: I/O resource not set for host"
 		       " bridge %s (domain %d)\n",
 		       hose->dn->full_name, hose->global_number);
-#ifdef CONFIG_PPC32
-		/* Workaround for lack of IO resource only on 32-bit */
-		res->start = (unsigned long)hose->io_base_virt - isa_io_base;
-		res->end = res->start + IO_SPACE_LIMIT;
-		res->flags = IORESOURCE_IO;
-#endif /* CONFIG_PPC32 */
-	}
-	if (res->flags) {
-		pr_debug("PCI: PHB IO resource    = %016llx-%016llx [%lx]\n",
+	} else {
+		offset = pcibios_io_space_offset(hose);
+
+		pr_debug("PCI: PHB IO resource    = %08llx-%08llx [%lx] off 0x%08llx\n",
 			 (unsigned long long)res->start,
 			 (unsigned long long)res->end,
-			 (unsigned long)res->flags);
-		pci_add_resource_offset(resources, res, pcibios_io_space_offset(hose));
-
-		pr_debug("PCI: PHB IO  offset     = %08lx\n",
-			 (unsigned long)hose->io_base_virt - _IO_BASE);
+			 (unsigned long)res->flags,
+			 (unsigned long long)offset);
+		pci_add_resource_offset(resources, res, offset);
 	}
 
 	/* Hookup PHB Memory resources */
 	for (i = 0; i < 3; ++i) {
 		res = &hose->mem_resources[i];
 		if (!res->flags) {
-			if (i > 0)
-				continue;
 			printk(KERN_ERR "PCI: Memory resource 0 not set for "
 			       "host bridge %s (domain %d)\n",
 			       hose->dn->full_name, hose->global_number);
-#ifdef CONFIG_PPC32
-			/* Workaround for lack of MEM resource only on 32-bit */
-			res->start = hose->pci_mem_offset;
-			res->end = (resource_size_t)-1LL;
-			res->flags = IORESOURCE_MEM;
-#endif /* CONFIG_PPC32 */
+			continue;
 		}
-		if (res->flags) {
-			pr_debug("PCI: PHB MEM resource %d = %016llx-%016llx [%lx]\n", i,
-				 (unsigned long long)res->start,
-				 (unsigned long long)res->end,
-				 (unsigned long)res->flags);
-			pci_add_resource_offset(resources, res, hose->pci_mem_offset);
-		}
-	}
+		offset = hose->mem_offset[i];
 
-	pr_debug("PCI: PHB MEM offset     = %016llx\n",
-		 (unsigned long long)hose->pci_mem_offset);
+
+		pr_debug("PCI: PHB MEM resource %d = %08llx-%08llx [%lx] off 0x%08llx\n", i,
+			 (unsigned long long)res->start,
+			 (unsigned long long)res->end,
+			 (unsigned long)res->flags,
+			 (unsigned long long)offset);
+
+		pci_add_resource_offset(resources, res, offset);
+	}
 }
 
 /*
diff --git a/arch/powerpc/kernel/pci_32.c b/arch/powerpc/kernel/pci_32.c
index e37c215..432459c 100644
--- a/arch/powerpc/kernel/pci_32.c
+++ b/arch/powerpc/kernel/pci_32.c
@@ -295,7 +295,7 @@
 	case IOBASE_BRIDGE_NUMBER:
 		return (long)hose->first_busno;
 	case IOBASE_MEMORY:
-		return (long)hose->pci_mem_offset;
+		return (long)hose->mem_offset[0];
 	case IOBASE_IO:
 		return (long)hose->io_base_phys;
 	case IOBASE_ISA_IO:
diff --git a/arch/powerpc/kernel/pci_64.c b/arch/powerpc/kernel/pci_64.c
index 51a133a..873050d 100644
--- a/arch/powerpc/kernel/pci_64.c
+++ b/arch/powerpc/kernel/pci_64.c
@@ -246,7 +246,7 @@
 	case IOBASE_BRIDGE_NUMBER:
 		return (long)hose->first_busno;
 	case IOBASE_MEMORY:
-		return (long)hose->pci_mem_offset;
+		return (long)hose->mem_offset[0];
 	case IOBASE_IO:
 		return (long)hose->io_base_phys;
 	case IOBASE_ISA_IO:
diff --git a/arch/powerpc/platforms/embedded6xx/mpc10x.h b/arch/powerpc/platforms/embedded6xx/mpc10x.h
index b30a6a3..b290b63 100644
--- a/arch/powerpc/platforms/embedded6xx/mpc10x.h
+++ b/arch/powerpc/platforms/embedded6xx/mpc10x.h
@@ -81,17 +81,6 @@
 #define	MPC10X_MAPB_PCI_MEM_OFFSET	(MPC10X_MAPB_ISA_MEM_BASE -	\
 					 MPC10X_MAPB_PCI_MEM_START)
 
-/* Set hose members to values appropriate for the mem map used */
-#define	MPC10X_SETUP_HOSE(hose, map) {					\
-	(hose)->pci_mem_offset = MPC10X_MAP##map##_PCI_MEM_OFFSET;	\
-	(hose)->io_space.start = MPC10X_MAP##map##_PCI_IO_START;	\
-	(hose)->io_space.end = MPC10X_MAP##map##_PCI_IO_END;		\
-	(hose)->mem_space.start = MPC10X_MAP##map##_PCI_MEM_START;	\
-	(hose)->mem_space.end = MPC10X_MAP##map##_PCI_MEM_END;		\
-	(hose)->io_base_virt = (void *)MPC10X_MAP##map##_ISA_IO_BASE;	\
-}
-
-
 /* Miscellaneous Configuration register offsets */
 #define	MPC10X_CFG_PIR_REG		0x09
 #define	MPC10X_CFG_PIR_HOST_BRIDGE	0x00
diff --git a/arch/powerpc/platforms/powermac/pci.c b/arch/powerpc/platforms/powermac/pci.c
index 2b8af75..cf7009b 100644
--- a/arch/powerpc/platforms/powermac/pci.c
+++ b/arch/powerpc/platforms/powermac/pci.c
@@ -824,6 +824,7 @@
 			hose->mem_resources[cur].name = hose->dn->full_name;
 			hose->mem_resources[cur].start = base;
 			hose->mem_resources[cur].end = end;
+			hose->mem_offset[cur] = 0;
 			DBG("  %d: 0x%08lx-0x%08lx\n", cur, base, end);
 		} else {
 			DBG("   :           -0x%08lx\n", end);
@@ -866,7 +867,6 @@
 	hose->io_resource.start = 0;
 	hose->io_resource.end = 0x003fffff;
 	hose->io_resource.flags = IORESOURCE_IO;
-	hose->pci_mem_offset = 0;
 	hose->first_busno = 0;
 	hose->last_busno = 0xef;
 
diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index 97b08fc..1da578b 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -915,11 +915,14 @@
 				index++;
 			}
 		} else if (res->flags & IORESOURCE_MEM) {
+			/* WARNING: Assumes M32 is mem region 0 in PHB. We need to
+			 * harden that algorithm when we start supporting M64
+			 */
 			region.start = res->start -
-				       hose->pci_mem_offset -
+				       hose->mem_offset[0] -
 				       phb->ioda.m32_pci_base;
 			region.end   = res->end -
-				       hose->pci_mem_offset -
+				       hose->mem_offset[0] -
 				       phb->ioda.m32_pci_base;
 			index = region.start / phb->ioda.m32_segsize;
 
@@ -1115,8 +1118,7 @@
 	phb->ioda.m32_size += 0x10000;
 
 	phb->ioda.m32_segsize = phb->ioda.m32_size / phb->ioda.total_pe;
-	phb->ioda.m32_pci_base = hose->mem_resources[0].start -
-		hose->pci_mem_offset;
+	phb->ioda.m32_pci_base = hose->mem_resources[0].start - hose->mem_offset[0];
 	phb->ioda.io_size = hose->pci_io_size;
 	phb->ioda.io_segsize = phb->ioda.io_size / phb->ioda.total_pe;
 	phb->ioda.io_pci_base = 0; /* XXX calculate this ? */
diff --git a/arch/powerpc/platforms/wsp/wsp_pci.c b/arch/powerpc/platforms/wsp/wsp_pci.c
index 8e22f56..62cb527 100644
--- a/arch/powerpc/platforms/wsp/wsp_pci.c
+++ b/arch/powerpc/platforms/wsp/wsp_pci.c
@@ -502,7 +502,7 @@
 		 (~(hose->mem_resources[0].end -
 		    hose->mem_resources[0].start)) & 0x3ffffff0000ul);
 	out_be64(hose->cfg_data + PCIE_REG_M32A_START_ADDR,
-		 (hose->mem_resources[0].start - hose->pci_mem_offset) | 1);
+		 (hose->mem_resources[0].start - hose->mem_offset[0]) | 1);
 
 	/* Clear all TVT entries
 	 *
diff --git a/arch/powerpc/sysdev/fsl_pci.c b/arch/powerpc/sysdev/fsl_pci.c
index cffe7ed..028ac1f 100644
--- a/arch/powerpc/sysdev/fsl_pci.c
+++ b/arch/powerpc/sysdev/fsl_pci.c
@@ -178,7 +178,7 @@
 	struct ccsr_pci __iomem *pci = hose->private_data;
 	int i, j, n, mem_log, win_idx = 3, start_idx = 1, end_idx = 4;
 	u64 mem, sz, paddr_hi = 0;
-	u64 paddr_lo = ULLONG_MAX;
+	u64 offset = 0, paddr_lo = ULLONG_MAX;
 	u32 pcicsrbar = 0, pcicsrbar_sz;
 	u32 piwar = PIWAR_EN | PIWAR_PF | PIWAR_TGI_LOCAL |
 			PIWAR_READ_SNOOP | PIWAR_WRITE_SNOOP;
@@ -208,8 +208,9 @@
 		paddr_lo = min(paddr_lo, (u64)hose->mem_resources[i].start);
 		paddr_hi = max(paddr_hi, (u64)hose->mem_resources[i].end);
 
-		n = setup_one_atmu(pci, j, &hose->mem_resources[i],
-				   hose->pci_mem_offset);
+		/* We assume all memory resources have the same offset */
+		offset = hose->mem_offset[i];
+		n = setup_one_atmu(pci, j, &hose->mem_resources[i], offset);
 
 		if (n < 0 || j >= 5) {
 			pr_err("Ran out of outbound PCI ATMUs for resource %d!\n", i);
@@ -239,8 +240,8 @@
 	}
 
 	/* convert to pci address space */
-	paddr_hi -= hose->pci_mem_offset;
-	paddr_lo -= hose->pci_mem_offset;
+	paddr_hi -= offset;
+	paddr_lo -= offset;
 
 	if (paddr_hi == paddr_lo) {
 		pr_err("%s: No outbound window space\n", name);
diff --git a/arch/powerpc/sysdev/ppc4xx_pci.c b/arch/powerpc/sysdev/ppc4xx_pci.c
index 56e8b3c..64603a1 100644
--- a/arch/powerpc/sysdev/ppc4xx_pci.c
+++ b/arch/powerpc/sysdev/ppc4xx_pci.c
@@ -257,6 +257,7 @@
 	/* Setup outbound memory windows */
 	for (i = j = 0; i < 3; i++) {
 		struct resource *res = &hose->mem_resources[i];
+		resource_size_t offset = hose->mem_offset[i];
 
 		/* we only care about memory windows */
 		if (!(res->flags & IORESOURCE_MEM))
@@ -270,7 +271,7 @@
 		/* Configure the resource */
 		if (ppc4xx_setup_one_pci_PMM(hose, reg,
 					     res->start,
-					     res->start - hose->pci_mem_offset,
+					     res->start - offset,
 					     resource_size(res),
 					     res->flags,
 					     j) == 0) {
@@ -279,7 +280,7 @@
 			/* If the resource PCI address is 0 then we have our
 			 * ISA memory hole
 			 */
-			if (res->start == hose->pci_mem_offset)
+			if (res->start == offset)
 				found_isa_hole = 1;
 		}
 	}
@@ -457,6 +458,7 @@
 	/* Setup outbound memory windows */
 	for (i = j = 0; i < 3; i++) {
 		struct resource *res = &hose->mem_resources[i];
+		resource_size_t offset = hose->mem_offset[i];
 
 		/* we only care about memory windows */
 		if (!(res->flags & IORESOURCE_MEM))
@@ -470,7 +472,7 @@
 		/* Configure the resource */
 		if (ppc4xx_setup_one_pcix_POM(hose, reg,
 					      res->start,
-					      res->start - hose->pci_mem_offset,
+					      res->start - offset,
 					      resource_size(res),
 					      res->flags,
 					      j) == 0) {
@@ -479,7 +481,7 @@
 			/* If the resource PCI address is 0 then we have our
 			 * ISA memory hole
 			 */
-			if (res->start == hose->pci_mem_offset)
+			if (res->start == offset)
 				found_isa_hole = 1;
 		}
 	}
@@ -1792,6 +1794,7 @@
 	/* Setup outbound memory windows */
 	for (i = j = 0; i < 3; i++) {
 		struct resource *res = &hose->mem_resources[i];
+		resource_size_t offset = hose->mem_offset[i];
 
 		/* we only care about memory windows */
 		if (!(res->flags & IORESOURCE_MEM))
@@ -1805,7 +1808,7 @@
 		/* Configure the resource */
 		if (ppc4xx_setup_one_pciex_POM(port, hose, mbase,
 					       res->start,
-					       res->start - hose->pci_mem_offset,
+					       res->start - offset,
 					       resource_size(res),
 					       res->flags,
 					       j) == 0) {
@@ -1814,7 +1817,7 @@
 			/* If the resource PCI address is 0 then we have our
 			 * ISA memory hole
 			 */
-			if (res->start == hose->pci_mem_offset)
+			if (res->start == offset)
 				found_isa_hole = 1;
 		}
 	}