1// SPDX-License-Identifier: GPL-2.0
2#include <linux/init.h>
3#include <linux/pci.h>
4#include <linux/range.h>
5
6#include "bus_numa.h"
7
8LIST_HEAD(pci_root_infos);
9
10static struct pci_root_info *x86_find_pci_root_info(int bus)
11{
12 struct pci_root_info *info;
13
14 list_for_each_entry(info, &pci_root_infos, list)
15 if (info->busn.start == bus)
16 return info;
17
18 return NULL;
19}
20
21int x86_pci_root_bus_node(int bus)
22{
23 struct pci_root_info *info = x86_find_pci_root_info(bus);
24
25 if (!info)
26 return NUMA_NO_NODE;
27
28 return info->node;
29}
30
31void x86_pci_root_bus_resources(int bus, struct list_head *resources)
32{
33 struct pci_root_info *info = x86_find_pci_root_info(bus);
34 struct pci_root_res *root_res;
35 struct resource_entry *window;
36 bool found = false;
37
38 if (!info)
39 goto default_resources;
40
41 printk(KERN_DEBUG "PCI: root bus %02x: hardware-probed resources\n",
42 bus);
43
44 /* already added by acpi ? */
45 resource_list_for_each_entry(window, resources)
46 if (window->res->flags & IORESOURCE_BUS) {
47 found = true;
48 break;
49 }
50
51 if (!found)
52 pci_add_resource(resources, res: &info->busn);
53
54 list_for_each_entry(root_res, &info->resources, list)
55 pci_add_resource(resources, res: &root_res->res);
56
57 return;
58
59default_resources:
60 /*
61 * We don't have any host bridge aperture information from the
62 * "native host bridge drivers," e.g., amd_bus or broadcom_bus,
63 * so fall back to the defaults historically used by pci_create_bus().
64 */
65 printk(KERN_DEBUG "PCI: root bus %02x: using default resources\n", bus);
66 pci_add_resource(resources, res: &ioport_resource);
67 pci_add_resource(resources, res: &iomem_resource);
68}
69
70struct pci_root_info __init *alloc_pci_root_info(int bus_min, int bus_max,
71 int node, int link)
72{
73 struct pci_root_info *info;
74
75 info = kzalloc(size: sizeof(*info), GFP_KERNEL);
76
77 if (!info)
78 return info;
79
80 sprintf(buf: info->name, fmt: "PCI Bus #%02x", bus_min);
81
82 INIT_LIST_HEAD(list: &info->resources);
83 info->busn.name = info->name;
84 info->busn.start = bus_min;
85 info->busn.end = bus_max;
86 info->busn.flags = IORESOURCE_BUS;
87 info->node = node;
88 info->link = link;
89
90 list_add_tail(new: &info->list, head: &pci_root_infos);
91
92 return info;
93}
94
95void update_res(struct pci_root_info *info, resource_size_t start,
96 resource_size_t end, unsigned long flags, int merge)
97{
98 struct resource *res;
99 struct pci_root_res *root_res;
100
101 if (start > end)
102 return;
103
104 if (start == RESOURCE_SIZE_MAX)
105 return;
106
107 if (!merge)
108 goto addit;
109
110 /* try to merge it with old one */
111 list_for_each_entry(root_res, &info->resources, list) {
112 resource_size_t final_start, final_end;
113 resource_size_t common_start, common_end;
114
115 res = &root_res->res;
116 if (res->flags != flags)
117 continue;
118
119 common_start = max(res->start, start);
120 common_end = min(res->end, end);
121 if (common_start > common_end + 1)
122 continue;
123
124 final_start = min(res->start, start);
125 final_end = max(res->end, end);
126
127 res->start = final_start;
128 res->end = final_end;
129 return;
130 }
131
132addit:
133
134 /* need to add that */
135 root_res = kzalloc(size: sizeof(*root_res), GFP_KERNEL);
136 if (!root_res)
137 return;
138
139 res = &root_res->res;
140 res->name = info->name;
141 res->flags = flags;
142 res->start = start;
143 res->end = end;
144
145 list_add_tail(new: &root_res->list, head: &info->resources);
146}
147

source code of linux/arch/x86/pci/bus_numa.c