1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Generic PCI host driver common code
4 *
5 * Copyright (C) 2014 ARM Limited
6 *
7 * Author: Will Deacon <will.deacon@arm.com>
8 */
9
10#include <linux/kernel.h>
11#include <linux/module.h>
12#include <linux/of.h>
13#include <linux/of_address.h>
14#include <linux/of_pci.h>
15#include <linux/pci-ecam.h>
16#include <linux/platform_device.h>
17
18static void gen_pci_unmap_cfg(void *ptr)
19{
20	pci_ecam_free((struct pci_config_window *)ptr);
21}
22
23static struct pci_config_window *gen_pci_init(struct device *dev,
24		struct pci_host_bridge *bridge, const struct pci_ecam_ops *ops)
25{
26	int err;
27	struct resource cfgres;
28	struct resource_entry *bus;
29	struct pci_config_window *cfg;
30
31	err = of_address_to_resource(dev->of_node, 0, &cfgres);
32	if (err) {
33		dev_err(dev, "missing \"reg\" property\n");
34		return ERR_PTR(err);
35	}
36
37	bus = resource_list_first_type(&bridge->windows, IORESOURCE_BUS);
38	if (!bus)
39		return ERR_PTR(-ENODEV);
40
41	cfg = pci_ecam_create(dev, &cfgres, bus->res, ops);
42	if (IS_ERR(cfg))
43		return cfg;
44
45	err = devm_add_action_or_reset(dev, gen_pci_unmap_cfg, cfg);
46	if (err)
47		return ERR_PTR(err);
48
49	return cfg;
50}
51
52int pci_host_common_probe(struct platform_device *pdev)
53{
54	struct device *dev = &pdev->dev;
55	struct pci_host_bridge *bridge;
56	struct pci_config_window *cfg;
57	const struct pci_ecam_ops *ops;
58
59	ops = of_device_get_match_data(&pdev->dev);
60	if (!ops)
61		return -ENODEV;
62
63	bridge = devm_pci_alloc_host_bridge(dev, 0);
64	if (!bridge)
65		return -ENOMEM;
66
67	platform_set_drvdata(pdev, bridge);
68
69	of_pci_check_probe_only();
70
71	/* Parse and map our Configuration Space windows */
72	cfg = gen_pci_init(dev, bridge, ops);
73	if (IS_ERR(cfg))
74		return PTR_ERR(cfg);
75
76	/* Do not reassign resources if probe only */
77	if (!pci_has_flag(PCI_PROBE_ONLY))
78		pci_add_flags(PCI_REASSIGN_ALL_BUS);
79
80	bridge->sysdata = cfg;
81	bridge->ops = (struct pci_ops *)&ops->pci_ops;
82	bridge->msi_domain = true;
83
84	return pci_host_probe(bridge);
85}
86EXPORT_SYMBOL_GPL(pci_host_common_probe);
87
88void pci_host_common_remove(struct platform_device *pdev)
89{
90	struct pci_host_bridge *bridge = platform_get_drvdata(pdev);
91
92	pci_lock_rescan_remove();
93	pci_stop_root_bus(bridge->bus);
94	pci_remove_root_bus(bridge->bus);
95	pci_unlock_rescan_remove();
96}
97EXPORT_SYMBOL_GPL(pci_host_common_remove);
98
99MODULE_LICENSE("GPL v2");
100