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/of_address.h>
12 #include <linux/of_pci.h>
13 #include <linux/pci-ecam.h>
14 #include <linux/platform_device.h>
15
gen_pci_unmap_cfg(void * ptr)16 static void gen_pci_unmap_cfg(void *ptr)
17 {
18 pci_ecam_free((struct pci_config_window *)ptr);
19 }
20
gen_pci_init(struct device * dev,struct list_head * resources,struct pci_ecam_ops * ops)21 static struct pci_config_window *gen_pci_init(struct device *dev,
22 struct list_head *resources, struct pci_ecam_ops *ops)
23 {
24 int err;
25 struct resource cfgres;
26 struct resource *bus_range = NULL;
27 struct pci_config_window *cfg;
28
29 /* Parse our PCI ranges and request their resources */
30 err = pci_parse_request_of_pci_ranges(dev, resources, &bus_range);
31 if (err)
32 return ERR_PTR(err);
33
34 err = of_address_to_resource(dev->of_node, 0, &cfgres);
35 if (err) {
36 dev_err(dev, "missing \"reg\" property\n");
37 goto err_out;
38 }
39
40 cfg = pci_ecam_create(dev, &cfgres, bus_range, ops);
41 if (IS_ERR(cfg)) {
42 err = PTR_ERR(cfg);
43 goto err_out;
44 }
45
46 err = devm_add_action(dev, gen_pci_unmap_cfg, cfg);
47 if (err) {
48 gen_pci_unmap_cfg(cfg);
49 goto err_out;
50 }
51 return cfg;
52
53 err_out:
54 pci_free_resource_list(resources);
55 return ERR_PTR(err);
56 }
57
pci_host_common_probe(struct platform_device * pdev,struct pci_ecam_ops * ops)58 int pci_host_common_probe(struct platform_device *pdev,
59 struct pci_ecam_ops *ops)
60 {
61 const char *type;
62 struct device *dev = &pdev->dev;
63 struct device_node *np = dev->of_node;
64 struct pci_host_bridge *bridge;
65 struct pci_config_window *cfg;
66 struct list_head resources;
67 int ret;
68
69 bridge = devm_pci_alloc_host_bridge(dev, 0);
70 if (!bridge)
71 return -ENOMEM;
72
73 type = of_get_property(np, "device_type", NULL);
74 if (!type || strcmp(type, "pci")) {
75 dev_err(dev, "invalid \"device_type\" %s\n", type);
76 return -EINVAL;
77 }
78
79 of_pci_check_probe_only();
80
81 /* Parse and map our Configuration Space windows */
82 cfg = gen_pci_init(dev, &resources, ops);
83 if (IS_ERR(cfg))
84 return PTR_ERR(cfg);
85
86 /* Do not reassign resources if probe only */
87 if (!pci_has_flag(PCI_PROBE_ONLY))
88 pci_add_flags(PCI_REASSIGN_ALL_BUS);
89
90 list_splice_init(&resources, &bridge->windows);
91 bridge->dev.parent = dev;
92 bridge->sysdata = cfg;
93 bridge->busnr = cfg->busr.start;
94 bridge->ops = &ops->pci_ops;
95 bridge->map_irq = of_irq_parse_and_map_pci;
96 bridge->swizzle_irq = pci_common_swizzle;
97
98 ret = pci_host_probe(bridge);
99 if (ret < 0) {
100 pci_free_resource_list(&resources);
101 return ret;
102 }
103
104 platform_set_drvdata(pdev, bridge->bus);
105 return 0;
106 }
107
pci_host_common_remove(struct platform_device * pdev)108 int pci_host_common_remove(struct platform_device *pdev)
109 {
110 struct pci_bus *bus = platform_get_drvdata(pdev);
111
112 pci_lock_rescan_remove();
113 pci_stop_root_bus(bus);
114 pci_remove_root_bus(bus);
115 pci_unlock_rescan_remove();
116
117 return 0;
118 }
119