1 files changed, 54 insertions, 14 deletions

diff --git a/drivers/pci/of.c b/drivers/pci/of.c
index 51e3dd0ea5ab..dacea3fc5128 100644
--- a/drivers/pci/of.c
+++ b/drivers/pci/of.c
@@ -6,6 +6,7 @@
  */
 #define pr_fmt(fmt)	"PCI: OF: " fmt
 
+#include <linux/cleanup.h>
 #include <linux/irqdomain.h>
 #include <linux/kernel.h>
 #include <linux/pci.h>
@@ -13,6 +14,7 @@
 #include <linux/of_irq.h>
 #include <linux/of_address.h>
 #include <linux/of_pci.h>
+#include <linux/platform_device.h>
 #include "pci.h"
 
 #ifdef CONFIG_PCI
@@ -25,16 +27,20 @@
  */
 int pci_set_of_node(struct pci_dev *dev)
 {
-	struct device_node *node;
-
 	if (!dev->bus->dev.of_node)
 		return 0;
 
-	node = of_pci_find_child_device(dev->bus->dev.of_node, dev->devfn);
+	struct device_node *node __free(device_node) =
+		of_pci_find_child_device(dev->bus->dev.of_node, dev->devfn);
 	if (!node)
 		return 0;
 
-	device_set_node(&dev->dev, of_fwnode_handle(node));
+	struct device *pdev __free(put_device) =
+		bus_find_device_by_of_node(&platform_bus_type, node);
+	if (pdev)
+		dev->bus->dev.of_node_reused = true;
+
+	device_set_node(&dev->dev, of_fwnode_handle(no_free_ptr(node)));
 	return 0;
 }
 
@@ -234,27 +240,61 @@ int of_get_pci_domain_nr(struct device_node *node)
 EXPORT_SYMBOL_GPL(of_get_pci_domain_nr);
 
 /**
- * of_pci_check_probe_only - Setup probe only mode if linux,pci-probe-only
- *                           is present and valid
+ * of_pci_preserve_config - Return true if the boot configuration needs to
+ *                          be preserved
+ * @node: Device tree node.
+ *
+ * Look for "linux,pci-probe-only" property for a given PCI controller's
+ * node and return true if found. Also look in the chosen node if the
+ * property is not found in the given controller's node.  Having this
+ * property ensures that the kernel doesn't reconfigure the BARs and bridge
+ * windows that are already done by the platform firmware.
+ *
+ * Return: true if the property exists; false otherwise.
  */
-void of_pci_check_probe_only(void)
+bool of_pci_preserve_config(struct device_node *node)
 {
-	u32 val;
+	u32 val = 0;
 	int ret;
 
-	ret = of_property_read_u32(of_chosen, "linux,pci-probe-only", &val);
+	if (!node) {
+		pr_warn("device node is NULL, trying with of_chosen\n");
+		node = of_chosen;
+	}
+
+retry:
+	ret = of_property_read_u32(node, "linux,pci-probe-only", &val);
 	if (ret) {
-		if (ret == -ENODATA || ret == -EOVERFLOW)
-			pr_warn("linux,pci-probe-only without valid value, ignoring\n");
-		return;
+		if (ret == -ENODATA || ret == -EOVERFLOW) {
+			pr_warn("Incorrect value for linux,pci-probe-only in %pOF, ignoring\n",
+				node);
+			return false;
+		}
+		if (ret == -EINVAL) {
+			if (node == of_chosen)
+				return false;
+
+			node = of_chosen;
+			goto retry;
+		}
 	}
 
 	if (val)
+		return true;
+	else
+		return false;
+}
+
+/**
+ * of_pci_check_probe_only - Setup probe only mode if linux,pci-probe-only
+ *                           is present and valid
+ */
+void of_pci_check_probe_only(void)
+{
+	if (of_pci_preserve_config(of_chosen))
 		pci_add_flags(PCI_PROBE_ONLY);
 	else
 		pci_clear_flags(PCI_PROBE_ONLY);
-
-	pr_info("PROBE_ONLY %s\n", val ? "enabled" : "disabled");
 }
 EXPORT_SYMBOL_GPL(of_pci_check_probe_only);