PCI: OF: Add generic function to parse and allocate PCI resources

The patch moves the gen_pci_parse_request_of_pci_ranges() function from
drivers/pci/host/pci-host-common.c into drivers/pci/of.c to easily share
common source code between PCI host drivers.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@free-electrons.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

1 files changed, 51 insertions, 0 deletions

diff --git a/drivers/pci/of.c b/drivers/pci/of.c
index e112da11630e..54e210501b73 100644
--- a/drivers/pci/of.c
+++ b/drivers/pci/of.c
@@ -88,3 +88,54 @@ struct irq_domain *pci_host_bridge_of_msi_domain(struct pci_bus *bus)
 	return NULL;
 #endif
 }
+
+int pci_parse_request_of_pci_ranges(struct device *dev,
+				    struct list_head *resources,
+				    struct resource **bus_range)
+{
+	int err, res_valid = 0;
+	struct device_node *np = dev->of_node;
+	resource_size_t iobase;
+	struct resource_entry *win, *tmp;
+
+	INIT_LIST_HEAD(resources);
+	err = of_pci_get_host_bridge_resources(np, 0, 0xff, resources, &iobase);
+	if (err)
+		return err;
+
+	err = devm_request_pci_bus_resources(dev, resources);
+	if (err)
+		goto out_release_res;
+
+	resource_list_for_each_entry_safe(win, tmp, resources) {
+		struct resource *res = win->res;
+
+		switch (resource_type(res)) {
+		case IORESOURCE_IO:
+			err = pci_remap_iospace(res, iobase);
+			if (err) {
+				dev_warn(dev, "error %d: failed to map resource %pR\n",
+					 err, res);
+				resource_list_destroy_entry(win);
+			}
+			break;
+		case IORESOURCE_MEM:
+			res_valid |= !(res->flags & IORESOURCE_PREFETCH);
+			break;
+		case IORESOURCE_BUS:
+			if (bus_range)
+				*bus_range = res;
+			break;
+		}
+	}
+
+	if (res_valid)
+		return 0;
+
+	dev_err(dev, "non-prefetchable memory resource required\n");
+	err = -EINVAL;
+
+ out_release_res:
+	pci_free_resource_list(resources);
+	return err;
+}