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, &info->busn);
53
54	list_for_each_entry(root_res, &info->resources, list)
55		pci_add_resource(resources, &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, &ioport_resource);
67	pci_add_resource(resources, &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(sizeof(*info), GFP_KERNEL);
76
77	if (!info)
78		return info;
79
80	sprintf(info->name, "PCI Bus #%02x", bus_min);
81
82	INIT_LIST_HEAD(&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(&info->list, &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(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(&root_res->list, &info->resources);
146}
147