tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Generic PCI host driver common code
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public License
14 * along with this program. If not, see <http://www.gnu.org/licenses/>.
15 *
16 * Copyright (C) 2014 ARM Limited
17 *
18 * Author: Will Deacon <will.deacon@arm.com>
19 */
20
21#include <linux/kernel.h>
22#include <linux/of_address.h>
23#include <linux/of_pci.h>
24#include <linux/pci-ecam.h>
25#include <linux/platform_device.h>
26
27static int gen_pci_parse_request_of_pci_ranges(struct device *dev,
28 struct list_head *resources, struct resource **bus_range)
29{
30 int err, res_valid = 0;
31 struct device_node *np = dev->of_node;
32 resource_size_t iobase;
33 struct resource_entry *win, *tmp;
34
35 err = of_pci_get_host_bridge_resources(np, 0, 0xff, resources, &iobase);
36 if (err)
37 return err;
38
39 err = devm_request_pci_bus_resources(dev, resources);
40 if (err)
41 return err;
42
43 resource_list_for_each_entry_safe(win, tmp, resources) {
44 struct resource *res = win->res;
45
46 switch (resource_type(res)) {
47 case IORESOURCE_IO:
48 err = pci_remap_iospace(res, iobase);
49 if (err) {
50 dev_warn(dev, "error %d: failed to map resource %pR\n",
51 err, res);
52 resource_list_destroy_entry(win);
53 }
54 break;
55 case IORESOURCE_MEM:
56 res_valid |= !(res->flags & IORESOURCE_PREFETCH);
57 break;
58 case IORESOURCE_BUS:
59 *bus_range = res;
60 break;
61 }
62 }
63
64 if (res_valid)
65 return 0;
66
67 dev_err(dev, "non-prefetchable memory resource required\n");
68 return -EINVAL;
69}
70
71static void gen_pci_unmap_cfg(void *ptr)
72{
73 pci_ecam_free((struct pci_config_window *)ptr);
74}
75
76static struct pci_config_window *gen_pci_init(struct device *dev,
77 struct list_head *resources, struct pci_ecam_ops *ops)
78{
79 int err;
80 struct resource cfgres;
81 struct resource *bus_range = NULL;
82 struct pci_config_window *cfg;
83
84 /* Parse our PCI ranges and request their resources */
85 err = gen_pci_parse_request_of_pci_ranges(dev, resources, &bus_range);
86 if (err)
87 goto err_out;
88
89 err = of_address_to_resource(dev->of_node, 0, &cfgres);
90 if (err) {
91 dev_err(dev, "missing \"reg\" property\n");
92 goto err_out;
93 }
94
95 cfg = pci_ecam_create(dev, &cfgres, bus_range, ops);
96 if (IS_ERR(cfg)) {
97 err = PTR_ERR(cfg);
98 goto err_out;
99 }
100
101 err = devm_add_action(dev, gen_pci_unmap_cfg, cfg);
102 if (err) {
103 gen_pci_unmap_cfg(cfg);
104 goto err_out;
105 }
106 return cfg;
107
108err_out:
109 pci_free_resource_list(resources);
110 return ERR_PTR(err);
111}
112
113int pci_host_common_probe(struct platform_device *pdev,
114 struct pci_ecam_ops *ops)
115{
116 const char *type;
117 struct device *dev = &pdev->dev;
118 struct device_node *np = dev->of_node;
119 struct pci_bus *bus, *child;
120 struct pci_config_window *cfg;
121 struct list_head resources;
122
123 type = of_get_property(np, "device_type", NULL);
124 if (!type || strcmp(type, "pci")) {
125 dev_err(dev, "invalid \"device_type\" %s\n", type);
126 return -EINVAL;
127 }
128
129 of_pci_check_probe_only();
130
131 /* Parse and map our Configuration Space windows */
132 INIT_LIST_HEAD(&resources);
133 cfg = gen_pci_init(dev, &resources, ops);
134 if (IS_ERR(cfg))
135 return PTR_ERR(cfg);
136
137 /* Do not reassign resources if probe only */
138 if (!pci_has_flag(PCI_PROBE_ONLY))
139 pci_add_flags(PCI_REASSIGN_ALL_RSRC | PCI_REASSIGN_ALL_BUS);
140
141 bus = pci_scan_root_bus(dev, cfg->busr.start, &ops->pci_ops, cfg,
142 &resources);
143 if (!bus) {
144 dev_err(dev, "Scanning rootbus failed");
145 return -ENODEV;
146 }
147
148#ifdef CONFIG_ARM
149 pci_fixup_irqs(pci_common_swizzle, of_irq_parse_and_map_pci);
150#endif
151
152 /*
153 * We insert PCI resources into the iomem_resource and
154 * ioport_resource trees in either pci_bus_claim_resources()
155 * or pci_bus_assign_resources().
156 */
157 if (pci_has_flag(PCI_PROBE_ONLY)) {
158 pci_bus_claim_resources(bus);
159 } else {
160 pci_bus_size_bridges(bus);
161 pci_bus_assign_resources(bus);
162
163 list_for_each_entry(child, &bus->children, node)
164 pcie_bus_configure_settings(child);
165 }
166
167 pci_bus_add_devices(bus);
168 return 0;
169}