dm: pci: Use the correct hose when configuring devices

Only the PCI controller has access to the PCI region information. Make sure
to use the controller (rather than any attached bridges) when configuring
devices.

This corrects a failure to scan and configure devices when driver model is
enabled for PCI.

Also add a comment to explain the problem.

Signed-off-by: Simon Glass <sjg@chromium.org>

drivers/pci/pci-uclass.c

@@ -296,6 +296,7 @@ int pci_auto_config_devices(struct udevice *bus)
 	     !ret && dev;
 	     ret = device_find_next_child(&dev)) {
 		struct pci_child_platdata *pplat;
+		struct pci_controller *ctlr_hose;
 
 		pplat = dev_get_parent_platdata(dev);
 		unsigned int max_bus;
@@ -303,7 +304,10 @@ int pci_auto_config_devices(struct udevice *bus)
 
 		bdf = PCI_ADD_BUS(bus->seq, pplat->devfn);
 		debug("%s: device %s\n", __func__, dev->name);
-		max_bus = pciauto_config_device(hose, bdf);
+
+		/* The root controller has the region information */
+		ctlr_hose = hose->ctlr->uclass_priv;
+		max_bus = pciauto_config_device(ctlr_hose, bdf);
 		sub_bus = max(sub_bus, max_bus);
 	}
 	debug("%s: done\n", __func__);

drivers/pci/pci_common.c

@@ -11,6 +11,7 @@
  */
 
 #include <common.h>
+#include <dm.h>
 #include <errno.h>
 #include <pci.h>
 #include <asm/io.h>
@@ -221,6 +222,11 @@ phys_addr_t pci_hose_bus_to_phys(struct pci_controller *hose,
 		return phys_addr;
 	}
 
+#ifdef CONFIG_DM_PCI
+	/* The root controller has the region information */
+	hose = hose->ctlr->uclass_priv;
+#endif
+
 	/*
 	 * if PCI_REGION_MEM is set we do a two pass search with preference
 	 * on matches that don't have PCI_REGION_SYS_MEMORY set

include/pci.h

@@ -513,6 +513,16 @@ struct pci_controller {
 
 	int indirect_type;
 
+	/*
+	 * TODO(sjg@chromium.org): With driver model we use struct
+	 * pci_controller for both the controller and any bridge devices
+	 * attached to it. But there is only one region list and it is in the
+	 * top-level controller.
+	 *
+	 * This could be changed so that struct pci_controller is only used
+	 * for PCI controllers and a separate UCLASS (or perhaps
+	 * UCLASS_PCI_GENERIC) is used for bridges.
+	 */
 	struct pci_region regions[MAX_PCI_REGIONS];
 	int region_count;