xref: /openbmc/linux/arch/x86/pci/bus_numa.c (revision 3a83e4e6)
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 
8 LIST_HEAD(pci_root_infos);
9 
10 static 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 
21 int 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 
31 void 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 
59 default_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 
70 struct 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 
95 void 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 == MAX_RESOURCE)
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 
132 addit:
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