xref: /linux/arch/sh/drivers/pci/pci.c (revision e9f0878c4b2004ac19581274c1ae4c61ae3ca70e)
1 /*
2  * New-style PCI core.
3  *
4  * Copyright (c) 2004 - 2009  Paul Mundt
5  * Copyright (c) 2002  M. R. Brown
6  *
7  * Modelled after arch/mips/pci/pci.c:
8  *  Copyright (C) 2003, 04 Ralf Baechle (ralf@linux-mips.org)
9  *
10  * This file is subject to the terms and conditions of the GNU General Public
11  * License.  See the file "COPYING" in the main directory of this archive
12  * for more details.
13  */
14 #include <linux/kernel.h>
15 #include <linux/mm.h>
16 #include <linux/pci.h>
17 #include <linux/init.h>
18 #include <linux/types.h>
19 #include <linux/dma-debug.h>
20 #include <linux/io.h>
21 #include <linux/mutex.h>
22 #include <linux/spinlock.h>
23 #include <linux/export.h>
24 
25 unsigned long PCIBIOS_MIN_IO = 0x0000;
26 unsigned long PCIBIOS_MIN_MEM = 0;
27 
28 /*
29  * The PCI controller list.
30  */
31 static struct pci_channel *hose_head, **hose_tail = &hose_head;
32 
33 static int pci_initialized;
34 
35 static void pcibios_scanbus(struct pci_channel *hose)
36 {
37 	static int next_busno;
38 	static int need_domain_info;
39 	LIST_HEAD(resources);
40 	struct resource *res;
41 	resource_size_t offset;
42 	int i, ret;
43 	struct pci_host_bridge *bridge;
44 
45 	bridge = pci_alloc_host_bridge(0);
46 	if (!bridge)
47 		return;
48 
49 	for (i = 0; i < hose->nr_resources; i++) {
50 		res = hose->resources + i;
51 		offset = 0;
52 		if (res->flags & IORESOURCE_DISABLED)
53 			continue;
54 		if (res->flags & IORESOURCE_IO)
55 			offset = hose->io_offset;
56 		else if (res->flags & IORESOURCE_MEM)
57 			offset = hose->mem_offset;
58 		pci_add_resource_offset(&resources, res, offset);
59 	}
60 
61 	list_splice_init(&resources, &bridge->windows);
62 	bridge->dev.parent = NULL;
63 	bridge->sysdata = hose;
64 	bridge->busnr = next_busno;
65 	bridge->ops = hose->pci_ops;
66 	bridge->swizzle_irq = pci_common_swizzle;
67 	bridge->map_irq = pcibios_map_platform_irq;
68 
69 	ret = pci_scan_root_bus_bridge(bridge);
70 	if (ret) {
71 		pci_free_host_bridge(bridge);
72 		return;
73 	}
74 
75 	hose->bus = bridge->bus;
76 
77 	need_domain_info = need_domain_info || hose->index;
78 	hose->need_domain_info = need_domain_info;
79 
80 	next_busno = hose->bus->busn_res.end + 1;
81 	/* Don't allow 8-bit bus number overflow inside the hose -
82 	   reserve some space for bridges. */
83 	if (next_busno > 224) {
84 		next_busno = 0;
85 		need_domain_info = 1;
86 	}
87 
88 	pci_bus_size_bridges(hose->bus);
89 	pci_bus_assign_resources(hose->bus);
90 	pci_bus_add_devices(hose->bus);
91 }
92 
93 /*
94  * This interrupt-safe spinlock protects all accesses to PCI
95  * configuration space.
96  */
97 DEFINE_RAW_SPINLOCK(pci_config_lock);
98 static DEFINE_MUTEX(pci_scan_mutex);
99 
100 int register_pci_controller(struct pci_channel *hose)
101 {
102 	int i;
103 
104 	for (i = 0; i < hose->nr_resources; i++) {
105 		struct resource *res = hose->resources + i;
106 
107 		if (res->flags & IORESOURCE_DISABLED)
108 			continue;
109 
110 		if (res->flags & IORESOURCE_IO) {
111 			if (request_resource(&ioport_resource, res) < 0)
112 				goto out;
113 		} else {
114 			if (request_resource(&iomem_resource, res) < 0)
115 				goto out;
116 		}
117 	}
118 
119 	*hose_tail = hose;
120 	hose_tail = &hose->next;
121 
122 	/*
123 	 * Do not panic here but later - this might happen before console init.
124 	 */
125 	if (!hose->io_map_base) {
126 		printk(KERN_WARNING
127 		       "registering PCI controller with io_map_base unset\n");
128 	}
129 
130 	/*
131 	 * Setup the ERR/PERR and SERR timers, if available.
132 	 */
133 	pcibios_enable_timers(hose);
134 
135 	/*
136 	 * Scan the bus if it is register after the PCI subsystem
137 	 * initialization.
138 	 */
139 	if (pci_initialized) {
140 		mutex_lock(&pci_scan_mutex);
141 		pcibios_scanbus(hose);
142 		mutex_unlock(&pci_scan_mutex);
143 	}
144 
145 	return 0;
146 
147 out:
148 	for (--i; i >= 0; i--)
149 		release_resource(&hose->resources[i]);
150 
151 	printk(KERN_WARNING "Skipping PCI bus scan due to resource conflict\n");
152 	return -1;
153 }
154 
155 static int __init pcibios_init(void)
156 {
157 	struct pci_channel *hose;
158 
159 	/* Scan all of the recorded PCI controllers.  */
160 	for (hose = hose_head; hose; hose = hose->next)
161 		pcibios_scanbus(hose);
162 
163 	pci_initialized = 1;
164 
165 	return 0;
166 }
167 subsys_initcall(pcibios_init);
168 
169 /*
170  * We need to avoid collisions with `mirrored' VGA ports
171  * and other strange ISA hardware, so we always want the
172  * addresses to be allocated in the 0x000-0x0ff region
173  * modulo 0x400.
174  */
175 resource_size_t pcibios_align_resource(void *data, const struct resource *res,
176 				resource_size_t size, resource_size_t align)
177 {
178 	struct pci_dev *dev = data;
179 	struct pci_channel *hose = dev->sysdata;
180 	resource_size_t start = res->start;
181 
182 	if (res->flags & IORESOURCE_IO) {
183 		if (start < PCIBIOS_MIN_IO + hose->resources[0].start)
184 			start = PCIBIOS_MIN_IO + hose->resources[0].start;
185 
186 		/*
187                  * Put everything into 0x00-0xff region modulo 0x400.
188 		 */
189 		if (start & 0x300)
190 			start = (start + 0x3ff) & ~0x3ff;
191 	}
192 
193 	return start;
194 }
195 
196 static void __init
197 pcibios_bus_report_status_early(struct pci_channel *hose,
198 				int top_bus, int current_bus,
199 				unsigned int status_mask, int warn)
200 {
201 	unsigned int pci_devfn;
202 	u16 status;
203 	int ret;
204 
205 	for (pci_devfn = 0; pci_devfn < 0xff; pci_devfn++) {
206 		if (PCI_FUNC(pci_devfn))
207 			continue;
208 		ret = early_read_config_word(hose, top_bus, current_bus,
209 					     pci_devfn, PCI_STATUS, &status);
210 		if (ret != PCIBIOS_SUCCESSFUL)
211 			continue;
212 		if (status == 0xffff)
213 			continue;
214 
215 		early_write_config_word(hose, top_bus, current_bus,
216 					pci_devfn, PCI_STATUS,
217 					status & status_mask);
218 		if (warn)
219 			printk("(%02x:%02x: %04X) ", current_bus,
220 			       pci_devfn, status);
221 	}
222 }
223 
224 /*
225  * We can't use pci_find_device() here since we are
226  * called from interrupt context.
227  */
228 static void __ref
229 pcibios_bus_report_status(struct pci_bus *bus, unsigned int status_mask,
230 			  int warn)
231 {
232 	struct pci_dev *dev;
233 
234 	list_for_each_entry(dev, &bus->devices, bus_list) {
235 		u16 status;
236 
237 		/*
238 		 * ignore host bridge - we handle
239 		 * that separately
240 		 */
241 		if (dev->bus->number == 0 && dev->devfn == 0)
242 			continue;
243 
244 		pci_read_config_word(dev, PCI_STATUS, &status);
245 		if (status == 0xffff)
246 			continue;
247 
248 		if ((status & status_mask) == 0)
249 			continue;
250 
251 		/* clear the status errors */
252 		pci_write_config_word(dev, PCI_STATUS, status & status_mask);
253 
254 		if (warn)
255 			printk("(%s: %04X) ", pci_name(dev), status);
256 	}
257 
258 	list_for_each_entry(dev, &bus->devices, bus_list)
259 		if (dev->subordinate)
260 			pcibios_bus_report_status(dev->subordinate, status_mask, warn);
261 }
262 
263 void __ref pcibios_report_status(unsigned int status_mask, int warn)
264 {
265 	struct pci_channel *hose;
266 
267 	for (hose = hose_head; hose; hose = hose->next) {
268 		if (unlikely(!hose->bus))
269 			pcibios_bus_report_status_early(hose, hose_head->index,
270 					hose->index, status_mask, warn);
271 		else
272 			pcibios_bus_report_status(hose->bus, status_mask, warn);
273 	}
274 }
275 
276 #ifndef CONFIG_GENERIC_IOMAP
277 
278 void __iomem *__pci_ioport_map(struct pci_dev *dev,
279 			       unsigned long port, unsigned int nr)
280 {
281 	struct pci_channel *chan = dev->sysdata;
282 
283 	if (unlikely(!chan->io_map_base)) {
284 		chan->io_map_base = sh_io_port_base;
285 
286 		if (pci_domains_supported)
287 			panic("To avoid data corruption io_map_base MUST be "
288 			      "set with multiple PCI domains.");
289 	}
290 
291 	return (void __iomem *)(chan->io_map_base + port);
292 }
293 
294 void pci_iounmap(struct pci_dev *dev, void __iomem *addr)
295 {
296 	iounmap(addr);
297 }
298 EXPORT_SYMBOL(pci_iounmap);
299 
300 #endif /* CONFIG_GENERIC_IOMAP */
301 
302 EXPORT_SYMBOL(PCIBIOS_MIN_IO);
303 EXPORT_SYMBOL(PCIBIOS_MIN_MEM);
304