Added support for PCI prefetchable region and BARs
If a host controller sets up a region as prefetchable and
a device's BAR denotes it as prefetchable, allocate the
BAR into the prefetch region.

If a BAR is prefetchable and no prefetchable region has
been setup by the controller we fall back to allocating
the BAR into the normally memory region.
Patch by Kumar Gala 11 Jan 2006
diff --git a/drivers/pci_auto.c b/drivers/pci_auto.c
index 3302457..15f7432 100644
--- a/drivers/pci_auto.c
+++ b/drivers/pci_auto.c
@@ -77,6 +77,7 @@
 void pciauto_setup_device(struct pci_controller *hose,
 			  pci_dev_t dev, int bars_num,
 			  struct pci_region *mem,
+			  struct pci_region *prefetch,
 			  struct pci_region *io)
 {
 	unsigned int bar_value, bar_response, bar_size;
@@ -111,7 +112,10 @@
 				found_mem64 = 1;
 
 			bar_size = ~(bar_response & PCI_BASE_ADDRESS_MEM_MASK) + 1;
-			bar_res = mem;
+			if (prefetch && (bar_response & PCI_BASE_ADDRESS_MEM_PREFETCH))
+				bar_res = prefetch;
+			else
+				bar_res = mem;
 
 			DEBUGF("PCI Autoconfig: BAR %d, Mem, size=0x%x, ", bar_nr, bar_size);
 		}
@@ -148,6 +152,7 @@
 					 pci_dev_t dev, int sub_bus)
 {
 	struct pci_region *pci_mem = hose->pci_mem;
+	struct pci_region *pci_prefetch = hose->pci_prefetch;
 	struct pci_region *pci_io = hose->pci_io;
 	unsigned int cmdstat;
 
@@ -169,6 +174,21 @@
 		cmdstat |= PCI_COMMAND_MEMORY;
 	}
 
+	if (pci_prefetch) {
+		/* Round memory allocator to 1MB boundary */
+		pciauto_region_align(pci_prefetch, 0x100000);
+
+		/* Set up memory and I/O filter limits, assume 32-bit I/O space */
+		pci_hose_write_config_word(hose, dev, PCI_PREF_MEMORY_BASE,
+					(pci_prefetch->bus_lower & 0xfff00000) >> 16);
+
+		cmdstat |= PCI_COMMAND_MEMORY;
+	} else {
+		/* We don't support prefetchable memory for now, so disable */
+		pci_hose_write_config_word(hose, dev, PCI_PREF_MEMORY_BASE, 0x1000);
+		pci_hose_write_config_word(hose, dev, PCI_PREF_MEMORY_LIMIT, 0x1000);
+	}
+
 	if (pci_io) {
 		/* Round I/O allocator to 4KB boundary */
 		pciauto_region_align(pci_io, 0x1000);
@@ -181,10 +201,6 @@
 		cmdstat |= PCI_COMMAND_IO;
 	}
 
-	/* We don't support prefetchable memory for now, so disable */
-	pci_hose_write_config_word(hose, dev, PCI_PREF_MEMORY_BASE, 0x1000);
-	pci_hose_write_config_word(hose, dev, PCI_PREF_MEMORY_LIMIT, 0x1000);
-
 	/* Enable memory and I/O accesses, enable bus master */
 	pci_hose_write_config_dword(hose, dev, PCI_COMMAND, cmdstat | PCI_COMMAND_MASTER);
 }
@@ -193,6 +209,7 @@
 					  pci_dev_t dev, int sub_bus)
 {
 	struct pci_region *pci_mem = hose->pci_mem;
+	struct pci_region *pci_prefetch = hose->pci_prefetch;
 	struct pci_region *pci_io = hose->pci_io;
 
 	/* Configure bus number registers */
@@ -206,6 +223,14 @@
 					(pci_mem->bus_lower-1) >> 16);
 	}
 
+	if (pci_prefetch) {
+		/* Round memory allocator to 1MB boundary */
+		pciauto_region_align(pci_prefetch, 0x100000);
+
+		pci_hose_write_config_word(hose, dev, PCI_PREF_MEMORY_LIMIT,
+					(pci_prefetch->bus_lower-1) >> 16);
+	}
+
 	if (pci_io) {
 		/* Round I/O allocator to 4KB boundary */
 		pciauto_region_align(pci_io, 0x1000);
@@ -239,6 +264,11 @@
 			    hose->pci_mem->size < hose->regions[i].size)
 				hose->pci_mem = hose->regions + i;
 			break;
+		case (PCI_REGION_MEM | PCI_REGION_PREFETCH):
+			if (!hose->pci_prefetch ||
+			    hose->pci_prefetch->size < hose->regions[i].size)
+				hose->pci_prefetch = hose->regions + i;
+			break;
 		}
 	}
 
@@ -251,6 +281,14 @@
 		    hose->pci_mem->bus_start + hose->pci_mem->size - 1);
 	}
 
+	if (hose->pci_prefetch) {
+		pciauto_region_init(hose->pci_prefetch);
+
+		DEBUGF("PCI Autoconfig: Prefetchable Memory region: [%lx-%lx]\n",
+		    hose->pci_prefetch->bus_start,
+		    hose->pci_prefetch->bus_start + hose->pci_prefetch->size - 1);
+	}
+
 	if (hose->pci_io) {
 		pciauto_region_init(hose->pci_io);
 
@@ -275,7 +313,7 @@
 	switch(class) {
 	case PCI_CLASS_BRIDGE_PCI:
 		hose->current_busno++;
-		pciauto_setup_device(hose, dev, 2, hose->pci_mem, hose->pci_io);
+		pciauto_setup_device(hose, dev, 2, hose->pci_mem, hose->pci_prefetch, hose->pci_io);
 
 		DEBUGF("PCI Autoconfig: Found P2P bridge, device %d\n", PCI_DEV(dev));
 
@@ -301,12 +339,12 @@
 			return sub_bus;
 		}
 
-		pciauto_setup_device(hose, dev, 6, hose->pci_mem, hose->pci_io);
+		pciauto_setup_device(hose, dev, 6, hose->pci_mem, hose->pci_prefetch, hose->pci_io);
 		break;
 
 	case PCI_CLASS_BRIDGE_CARDBUS:
 		/* just do a minimal setup of the bridge, let the OS take care of the rest */
-		pciauto_setup_device(hose, dev, 0, hose->pci_mem, hose->pci_io);
+		pciauto_setup_device(hose, dev, 0, hose->pci_mem, hose->pci_prefetch, hose->pci_io);
 
 		DEBUGF("PCI Autoconfig: Found P2CardBus bridge, device %d\n", PCI_DEV(dev));
 
@@ -328,11 +366,11 @@
 		 * the PIMMR window to be allocated (BAR0 - 1MB size)
 		 */
 		DEBUGF("PCI Autoconfig: Broken bridge found, only minimal config\n");
-		pciauto_setup_device(hose, dev, 0, hose->pci_mem, hose->pci_io);
+		pciauto_setup_device(hose, dev, 0, hose->pci_mem, hose->pci_prefetch, hose->pci_io);
 		break;
 #endif
 	default:
-		pciauto_setup_device(hose, dev, 6, hose->pci_mem, hose->pci_io);
+		pciauto_setup_device(hose, dev, 6, hose->pci_mem, hose->pci_prefetch, hose->pci_io);
 		break;
 	}