1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * New-style PCI core.
4 *
5 * Copyright (c) 2004 - 2009 Paul Mundt
6 * Copyright (c) 2002 M. R. Brown
7 *
8 * Modelled after arch/mips/pci/pci.c:
9 * Copyright (C) 2003, 04 Ralf Baechle (ralf@linux-mips.org)
10 */
11 #include <linux/kernel.h>
12 #include <linux/mm.h>
13 #include <linux/pci.h>
14 #include <linux/init.h>
15 #include <linux/types.h>
16 #include <linux/dma-debug.h>
17 #include <linux/io.h>
18 #include <linux/mutex.h>
19 #include <linux/spinlock.h>
20 #include <linux/export.h>
21
22 unsigned long PCIBIOS_MIN_IO = 0x0000;
23 unsigned long PCIBIOS_MIN_MEM = 0;
24
25 /*
26 * The PCI controller list.
27 */
28 static struct pci_channel *hose_head, **hose_tail = &hose_head;
29
30 static int pci_initialized;
31
pcibios_scanbus(struct pci_channel * hose)32 static void pcibios_scanbus(struct pci_channel *hose)
33 {
34 static int next_busno;
35 static int need_domain_info;
36 LIST_HEAD(resources);
37 struct resource *res;
38 resource_size_t offset;
39 int i, ret;
40 struct pci_host_bridge *bridge;
41
42 bridge = pci_alloc_host_bridge(0);
43 if (!bridge)
44 return;
45
46 for (i = 0; i < hose->nr_resources; i++) {
47 res = hose->resources + i;
48 offset = 0;
49 if (res->flags & IORESOURCE_DISABLED)
50 continue;
51 if (res->flags & IORESOURCE_IO)
52 offset = hose->io_offset;
53 else if (res->flags & IORESOURCE_MEM)
54 offset = hose->mem_offset;
55 pci_add_resource_offset(&resources, res, offset);
56 }
57
58 list_splice_init(&resources, &bridge->windows);
59 bridge->dev.parent = NULL;
60 bridge->sysdata = hose;
61 bridge->busnr = next_busno;
62 bridge->ops = hose->pci_ops;
63 bridge->swizzle_irq = pci_common_swizzle;
64 bridge->map_irq = pcibios_map_platform_irq;
65
66 ret = pci_scan_root_bus_bridge(bridge);
67 if (ret) {
68 pci_free_host_bridge(bridge);
69 return;
70 }
71
72 hose->bus = bridge->bus;
73
74 need_domain_info = need_domain_info || hose->index;
75 hose->need_domain_info = need_domain_info;
76
77 next_busno = hose->bus->busn_res.end + 1;
78 /* Don't allow 8-bit bus number overflow inside the hose -
79 reserve some space for bridges. */
80 if (next_busno > 224) {
81 next_busno = 0;
82 need_domain_info = 1;
83 }
84
85 pci_bus_size_bridges(hose->bus);
86 pci_bus_assign_resources(hose->bus);
87 pci_bus_add_devices(hose->bus);
88 }
89
90 /*
91 * This interrupt-safe spinlock protects all accesses to PCI
92 * configuration space.
93 */
94 DEFINE_RAW_SPINLOCK(pci_config_lock);
95 static DEFINE_MUTEX(pci_scan_mutex);
96
register_pci_controller(struct pci_channel * hose)97 int register_pci_controller(struct pci_channel *hose)
98 {
99 int i;
100
101 for (i = 0; i < hose->nr_resources; i++) {
102 struct resource *res = hose->resources + i;
103
104 if (res->flags & IORESOURCE_DISABLED)
105 continue;
106
107 if (res->flags & IORESOURCE_IO) {
108 if (request_resource(&ioport_resource, res) < 0)
109 goto out;
110 } else {
111 if (request_resource(&iomem_resource, res) < 0)
112 goto out;
113 }
114 }
115
116 *hose_tail = hose;
117 hose_tail = &hose->next;
118
119 /*
120 * Do not panic here but later - this might happen before console init.
121 */
122 if (!hose->io_map_base) {
123 printk(KERN_WARNING
124 "registering PCI controller with io_map_base unset\n");
125 }
126
127 /*
128 * Setup the ERR/PERR and SERR timers, if available.
129 */
130 pcibios_enable_timers(hose);
131
132 /*
133 * Scan the bus if it is register after the PCI subsystem
134 * initialization.
135 */
136 if (pci_initialized) {
137 mutex_lock(&pci_scan_mutex);
138 pcibios_scanbus(hose);
139 mutex_unlock(&pci_scan_mutex);
140 }
141
142 return 0;
143
144 out:
145 for (--i; i >= 0; i--)
146 release_resource(&hose->resources[i]);
147
148 printk(KERN_WARNING "Skipping PCI bus scan due to resource conflict\n");
149 return -1;
150 }
151
pcibios_init(void)152 static int __init pcibios_init(void)
153 {
154 struct pci_channel *hose;
155
156 /* Scan all of the recorded PCI controllers. */
157 for (hose = hose_head; hose; hose = hose->next)
158 pcibios_scanbus(hose);
159
160 pci_initialized = 1;
161
162 return 0;
163 }
164 subsys_initcall(pcibios_init);
165
166 /*
167 * We need to avoid collisions with `mirrored' VGA ports
168 * and other strange ISA hardware, so we always want the
169 * addresses to be allocated in the 0x000-0x0ff region
170 * modulo 0x400.
171 */
pcibios_align_resource(void * data,const struct resource * res,resource_size_t size,resource_size_t align)172 resource_size_t pcibios_align_resource(void *data, const struct resource *res,
173 resource_size_t size, resource_size_t align)
174 {
175 struct pci_dev *dev = data;
176 struct pci_channel *hose = dev->sysdata;
177 resource_size_t start = res->start;
178
179 if (res->flags & IORESOURCE_IO) {
180 if (start < PCIBIOS_MIN_IO + hose->resources[0].start)
181 start = PCIBIOS_MIN_IO + hose->resources[0].start;
182
183 /*
184 * Put everything into 0x00-0xff region modulo 0x400.
185 */
186 if (start & 0x300)
187 start = (start + 0x3ff) & ~0x3ff;
188 }
189
190 return start;
191 }
192
193 static void __init
pcibios_bus_report_status_early(struct pci_channel * hose,int top_bus,int current_bus,unsigned int status_mask,int warn)194 pcibios_bus_report_status_early(struct pci_channel *hose,
195 int top_bus, int current_bus,
196 unsigned int status_mask, int warn)
197 {
198 unsigned int pci_devfn;
199 u16 status;
200 int ret;
201
202 for (pci_devfn = 0; pci_devfn < 0xff; pci_devfn++) {
203 if (PCI_FUNC(pci_devfn))
204 continue;
205 ret = early_read_config_word(hose, top_bus, current_bus,
206 pci_devfn, PCI_STATUS, &status);
207 if (ret != PCIBIOS_SUCCESSFUL)
208 continue;
209 if (status == 0xffff)
210 continue;
211
212 early_write_config_word(hose, top_bus, current_bus,
213 pci_devfn, PCI_STATUS,
214 status & status_mask);
215 if (warn)
216 printk("(%02x:%02x: %04X) ", current_bus,
217 pci_devfn, status);
218 }
219 }
220
221 /*
222 * We can't use pci_find_device() here since we are
223 * called from interrupt context.
224 */
225 static void __ref
pcibios_bus_report_status(struct pci_bus * bus,unsigned int status_mask,int warn)226 pcibios_bus_report_status(struct pci_bus *bus, unsigned int status_mask,
227 int warn)
228 {
229 struct pci_dev *dev;
230
231 list_for_each_entry(dev, &bus->devices, bus_list) {
232 u16 status;
233
234 /*
235 * ignore host bridge - we handle
236 * that separately
237 */
238 if (dev->bus->number == 0 && dev->devfn == 0)
239 continue;
240
241 pci_read_config_word(dev, PCI_STATUS, &status);
242 if (status == 0xffff)
243 continue;
244
245 if ((status & status_mask) == 0)
246 continue;
247
248 /* clear the status errors */
249 pci_write_config_word(dev, PCI_STATUS, status & status_mask);
250
251 if (warn)
252 printk("(%s: %04X) ", pci_name(dev), status);
253 }
254
255 list_for_each_entry(dev, &bus->devices, bus_list)
256 if (dev->subordinate)
257 pcibios_bus_report_status(dev->subordinate, status_mask, warn);
258 }
259
pcibios_report_status(unsigned int status_mask,int warn)260 void __ref pcibios_report_status(unsigned int status_mask, int warn)
261 {
262 struct pci_channel *hose;
263
264 for (hose = hose_head; hose; hose = hose->next) {
265 if (unlikely(!hose->bus))
266 pcibios_bus_report_status_early(hose, hose_head->index,
267 hose->index, status_mask, warn);
268 else
269 pcibios_bus_report_status(hose->bus, status_mask, warn);
270 }
271 }
272
273 #ifndef CONFIG_GENERIC_IOMAP
274
__pci_ioport_map(struct pci_dev * dev,unsigned long port,unsigned int nr)275 void __iomem *__pci_ioport_map(struct pci_dev *dev,
276 unsigned long port, unsigned int nr)
277 {
278 struct pci_channel *chan = dev->sysdata;
279
280 if (unlikely(!chan->io_map_base)) {
281 chan->io_map_base = sh_io_port_base;
282
283 if (pci_domains_supported)
284 panic("To avoid data corruption io_map_base MUST be "
285 "set with multiple PCI domains.");
286 }
287
288 return (void __iomem *)(chan->io_map_base + port);
289 }
290
pci_iounmap(struct pci_dev * dev,void __iomem * addr)291 void pci_iounmap(struct pci_dev *dev, void __iomem *addr)
292 {
293 iounmap(addr);
294 }
295 EXPORT_SYMBOL(pci_iounmap);
296
297 #endif /* CONFIG_GENERIC_IOMAP */
298
299 EXPORT_SYMBOL(PCIBIOS_MIN_IO);
300 EXPORT_SYMBOL(PCIBIOS_MIN_MEM);
301