of: unittest: Add pci_dt_testdrv pci driver

pci_dt_testdrv is bound to QEMU PCI Test Device. It reads
overlay_pci_node fdt fragment and apply it to Test Device. Then it
calls of_platform_default_populate() to populate the platform
devices.

Tested-by: Herve Codina <herve.codina@bootlin.com>
Signed-off-by: Lizhi Hou <lizhi.hou@amd.com>
Link: https://lore.kernel.org/r/1692120000-46900-6-git-send-email-lizhi.hou@amd.com
Signed-off-by: Rob Herring <robh@kernel.org>

3 files changed, 213 insertions, 1 deletions

diff --git a/drivers/of/unittest-data/Makefile b/drivers/of/unittest-data/Makefile
index ea5f4da68e23..1aa875088159 100644
--- a/drivers/of/unittest-data/Makefile
+++ b/drivers/of/unittest-data/Makefile
@@ -32,7 +32,8 @@ obj-$(CONFIG_OF_OVERLAY) += overlay.dtbo.o \
 			    overlay_gpio_02b.dtbo.o \
 			    overlay_gpio_03.dtbo.o \
 			    overlay_gpio_04a.dtbo.o \
-			    overlay_gpio_04b.dtbo.o
+			    overlay_gpio_04b.dtbo.o \
+			    overlay_pci_node.dtbo.o
 
 # enable creation of __symbols__ node
 DTC_FLAGS_overlay += -@
diff --git a/drivers/of/unittest-data/overlay_pci_node.dtso b/drivers/of/unittest-data/overlay_pci_node.dtso
new file mode 100644
index 000000000000..c05e52e9e44a
--- /dev/null
+++ b/drivers/of/unittest-data/overlay_pci_node.dtso
@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: GPL-2.0
+/dts-v1/;
+/ {
+	fragment@0 {
+		target-path="";
+		__overlay__ {
+			#address-cells = <3>;
+			#size-cells = <2>;
+			pci-ep-bus@0 {
+				compatible = "simple-bus";
+				#address-cells = <1>;
+				#size-cells = <1>;
+				ranges = <0x0 0x0 0x0 0x0 0x1000>;
+				reg = <0 0 0 0 0>;
+				unittest-pci@100 {
+					compatible = "unittest-pci";
+					reg = <0x100 0x200>;
+				};
+			};
+		};
+	};
+};
diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c
index b87dca37b5ec..939e33afc668 100644
--- a/drivers/of/unittest.c
+++ b/drivers/of/unittest.c
@@ -22,6 +22,7 @@
 #include <linux/slab.h>
 #include <linux/device.h>
 #include <linux/platform_device.h>
+#include <linux/pci.h>
 #include <linux/kernel.h>
 
 #include <linux/i2c.h>
@@ -3326,6 +3327,7 @@ OVERLAY_INFO_EXTERN(overlay_gpio_02b);
 OVERLAY_INFO_EXTERN(overlay_gpio_03);
 OVERLAY_INFO_EXTERN(overlay_gpio_04a);
 OVERLAY_INFO_EXTERN(overlay_gpio_04b);
+OVERLAY_INFO_EXTERN(overlay_pci_node);
 OVERLAY_INFO_EXTERN(overlay_bad_add_dup_node);
 OVERLAY_INFO_EXTERN(overlay_bad_add_dup_prop);
 OVERLAY_INFO_EXTERN(overlay_bad_phandle);
@@ -3361,6 +3363,7 @@ static struct overlay_info overlays[] = {
 	OVERLAY_INFO(overlay_gpio_03, 0),
 	OVERLAY_INFO(overlay_gpio_04a, 0),
 	OVERLAY_INFO(overlay_gpio_04b, 0),
+	OVERLAY_INFO(overlay_pci_node, 0),
 	OVERLAY_INFO(overlay_bad_add_dup_node, -EINVAL),
 	OVERLAY_INFO(overlay_bad_add_dup_prop, -EINVAL),
 	OVERLAY_INFO(overlay_bad_phandle, -EINVAL),
@@ -3731,6 +3734,191 @@ static inline __init void of_unittest_overlay_high_level(void) {}
 
 #endif
 
+#ifdef CONFIG_PCI_DYNAMIC_OF_NODES
+
+static int of_unittest_pci_dev_num;
+static int of_unittest_pci_child_num;
+
+/*
+ * PCI device tree node test driver
+ */
+static const struct pci_device_id testdrv_pci_ids[] = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_REDHAT, 0x5), }, /* PCI_VENDOR_ID_REDHAT */
+	{ 0, }
+};
+
+static int testdrv_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+	struct overlay_info *info;
+	struct device_node *dn;
+	int ret, ovcs_id;
+	u32 size;
+
+	dn = pdev->dev.of_node;
+	if (!dn) {
+		dev_err(&pdev->dev, "does not find bus endpoint");
+		return -EINVAL;
+	}
+
+	for (info = overlays; info && info->name; info++) {
+		if (!strcmp(info->name, "overlay_pci_node"))
+			break;
+	}
+	if (!info || !info->name) {
+		dev_err(&pdev->dev, "no overlay data for overlay_pci_node");
+		return -ENODEV;
+	}
+
+	size = info->dtbo_end - info->dtbo_begin;
+	ret = of_overlay_fdt_apply(info->dtbo_begin, size, &ovcs_id, dn);
+	of_node_put(dn);
+	if (ret)
+		return ret;
+
+	of_platform_default_populate(dn, NULL, &pdev->dev);
+	pci_set_drvdata(pdev, (void *)(uintptr_t)ovcs_id);
+
+	return 0;
+}
+
+static void testdrv_remove(struct pci_dev *pdev)
+{
+	int ovcs_id = (int)(uintptr_t)pci_get_drvdata(pdev);
+
+	of_platform_depopulate(&pdev->dev);
+	of_overlay_remove(&ovcs_id);
+}
+
+static struct pci_driver testdrv_driver = {
+	.name = "pci_dt_testdrv",
+	.id_table = testdrv_pci_ids,
+	.probe = testdrv_probe,
+	.remove = testdrv_remove,
+};
+
+static int unittest_pci_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	struct device *dev;
+	u64 exp_addr;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENODEV;
+
+	dev = &pdev->dev;
+	while (dev && !dev_is_pci(dev))
+		dev = dev->parent;
+	if (!dev) {
+		pr_err("unable to find parent device\n");
+		return -ENODEV;
+	}
+
+	exp_addr = pci_resource_start(to_pci_dev(dev), 0) + 0x100;
+	unittest(res->start == exp_addr, "Incorrect translated address %llx, expected %llx\n",
+		 (u64)res->start, exp_addr);
+
+	of_unittest_pci_child_num++;
+
+	return 0;
+}
+
+static const struct of_device_id unittest_pci_of_match[] = {
+	{ .compatible = "unittest-pci" },
+	{ }
+};
+
+static struct platform_driver unittest_pci_driver = {
+	.probe = unittest_pci_probe,
+	.driver = {
+		.name = "unittest-pci",
+		.of_match_table = unittest_pci_of_match,
+	},
+};
+
+static int of_unittest_pci_node_verify(struct pci_dev *pdev, bool add)
+{
+	struct device_node *pnp, *np = NULL;
+	struct device *child_dev;
+	char *path = NULL;
+	const __be32 *reg;
+	int rc = 0;
+
+	pnp = pdev->dev.of_node;
+	unittest(pnp, "Failed creating PCI dt node\n");
+	if (!pnp)
+		return -ENODEV;
+
+	if (add) {
+		path = kasprintf(GFP_KERNEL, "%pOF/pci-ep-bus@0/unittest-pci@100", pnp);
+		np = of_find_node_by_path(path);
+		unittest(np, "Failed to get unittest-pci node under PCI node\n");
+		if (!np) {
+			rc = -ENODEV;
+			goto failed;
+		}
+
+		reg = of_get_property(np, "reg", NULL);
+		unittest(reg, "Failed to get reg property\n");
+		if (!reg)
+			rc = -ENODEV;
+	} else {
+		path = kasprintf(GFP_KERNEL, "%pOF/pci-ep-bus@0", pnp);
+		np = of_find_node_by_path(path);
+		unittest(!np, "Child device tree node is not removed\n");
+		child_dev = device_find_any_child(&pdev->dev);
+		unittest(!child_dev, "Child device is not removed\n");
+	}
+
+failed:
+	kfree(path);
+	if (np)
+		of_node_put(np);
+
+	return rc;
+}
+
+static void __init of_unittest_pci_node(void)
+{
+	struct pci_dev *pdev = NULL;
+	int rc;
+
+	rc = pci_register_driver(&testdrv_driver);
+	unittest(!rc, "Failed to register pci test driver; rc = %d\n", rc);
+	if (rc)
+		return;
+
+	rc = platform_driver_register(&unittest_pci_driver);
+	if (unittest(!rc, "Failed to register unittest pci driver\n")) {
+		pci_unregister_driver(&testdrv_driver);
+		return;
+	}
+
+	while ((pdev = pci_get_device(PCI_VENDOR_ID_REDHAT, 0x5, pdev)) != NULL) {
+		of_unittest_pci_node_verify(pdev, true);
+		of_unittest_pci_dev_num++;
+	}
+	if (pdev)
+		pci_dev_put(pdev);
+
+	unittest(of_unittest_pci_dev_num,
+		 "No test PCI device been found. Please run QEMU with '-device pci-testdev'\n");
+	unittest(of_unittest_pci_dev_num == of_unittest_pci_child_num,
+		 "Child device number %d is not expected %d", of_unittest_pci_child_num,
+		 of_unittest_pci_dev_num);
+
+	platform_driver_unregister(&unittest_pci_driver);
+	pci_unregister_driver(&testdrv_driver);
+
+	while ((pdev = pci_get_device(PCI_VENDOR_ID_REDHAT, 0x5, pdev)) != NULL)
+		of_unittest_pci_node_verify(pdev, false);
+	if (pdev)
+		pci_dev_put(pdev);
+}
+#else
+static void __init of_unittest_pci_node(void) { }
+#endif
+
 static int __init of_unittest(void)
 {
 	struct device_node *np;
@@ -3781,6 +3969,7 @@ static int __init of_unittest(void)
 	of_unittest_platform_populate();
 	of_unittest_overlay();
 	of_unittest_lifecycle();
+	of_unittest_pci_node();
 
 	/* Double check linkage after removing testcase data */
 	of_unittest_check_tree_linkage();