xref: /linux/drivers/pci/controller/pci-host-common.c (revision d19deabe5a4566851f6ecade5ebd2e63c3248cf2)
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  
18  static void gen_pci_unmap_cfg(void *ptr)
19  {
20  	pci_ecam_free((struct pci_config_window *)ptr);
21  }
22  
23  static 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  
52  int 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  }
86  EXPORT_SYMBOL_GPL(pci_host_common_probe);
87  
88  void 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  }
97  EXPORT_SYMBOL_GPL(pci_host_common_remove);
98  
99  MODULE_LICENSE("GPL v2");
100