xref: /openbmc/linux/arch/mips/pci/pci-legacy.c (revision 8730046c)
1 /*
2  * This program is free software; you can redistribute	it and/or modify it
3  * under  the terms of	the GNU General	 Public License as published by the
4  * Free Software Foundation;  either version 2 of the  License, or (at your
5  * option) any later version.
6  *
7  * Copyright (C) 2003, 04, 11 Ralf Baechle (ralf@linux-mips.org)
8  * Copyright (C) 2011 Wind River Systems,
9  *   written by Ralf Baechle (ralf@linux-mips.org)
10  */
11 #include <linux/bug.h>
12 #include <linux/kernel.h>
13 #include <linux/mm.h>
14 #include <linux/bootmem.h>
15 #include <linux/export.h>
16 #include <linux/init.h>
17 #include <linux/types.h>
18 #include <linux/pci.h>
19 #include <linux/of_address.h>
20 
21 #include <asm/cpu-info.h>
22 
23 /*
24  * If PCI_PROBE_ONLY in pci_flags is set, we don't change any PCI resource
25  * assignments.
26  */
27 
28 /*
29  * The PCI controller list.
30  */
31 static LIST_HEAD(controllers);
32 
33 static int pci_initialized;
34 
35 /*
36  * We need to avoid collisions with `mirrored' VGA ports
37  * and other strange ISA hardware, so we always want the
38  * addresses to be allocated in the 0x000-0x0ff region
39  * modulo 0x400.
40  *
41  * Why? Because some silly external IO cards only decode
42  * the low 10 bits of the IO address. The 0x00-0xff region
43  * is reserved for motherboard devices that decode all 16
44  * bits, so it's ok to allocate at, say, 0x2800-0x28ff,
45  * but we want to try to avoid allocating at 0x2900-0x2bff
46  * which might have be mirrored at 0x0100-0x03ff..
47  */
48 resource_size_t
49 pcibios_align_resource(void *data, const struct resource *res,
50 		       resource_size_t size, resource_size_t align)
51 {
52 	struct pci_dev *dev = data;
53 	struct pci_controller *hose = dev->sysdata;
54 	resource_size_t start = res->start;
55 
56 	if (res->flags & IORESOURCE_IO) {
57 		/* Make sure we start at our min on all hoses */
58 		if (start < PCIBIOS_MIN_IO + hose->io_resource->start)
59 			start = PCIBIOS_MIN_IO + hose->io_resource->start;
60 
61 		/*
62 		 * Put everything into 0x00-0xff region modulo 0x400
63 		 */
64 		if (start & 0x300)
65 			start = (start + 0x3ff) & ~0x3ff;
66 	} else if (res->flags & IORESOURCE_MEM) {
67 		/* Make sure we start at our min on all hoses */
68 		if (start < PCIBIOS_MIN_MEM + hose->mem_resource->start)
69 			start = PCIBIOS_MIN_MEM + hose->mem_resource->start;
70 	}
71 
72 	return start;
73 }
74 
75 static void pcibios_scanbus(struct pci_controller *hose)
76 {
77 	static int next_busno;
78 	static int need_domain_info;
79 	LIST_HEAD(resources);
80 	struct pci_bus *bus;
81 
82 	if (hose->get_busno && pci_has_flag(PCI_PROBE_ONLY))
83 		next_busno = (*hose->get_busno)();
84 
85 	pci_add_resource_offset(&resources,
86 				hose->mem_resource, hose->mem_offset);
87 	pci_add_resource_offset(&resources,
88 				hose->io_resource, hose->io_offset);
89 	pci_add_resource_offset(&resources,
90 				hose->busn_resource, hose->busn_offset);
91 	bus = pci_scan_root_bus(NULL, next_busno, hose->pci_ops, hose,
92 				&resources);
93 	hose->bus = bus;
94 
95 	need_domain_info = need_domain_info || pci_domain_nr(bus);
96 	set_pci_need_domain_info(hose, need_domain_info);
97 
98 	if (!bus) {
99 		pci_free_resource_list(&resources);
100 		return;
101 	}
102 
103 	next_busno = bus->busn_res.end + 1;
104 	/* Don't allow 8-bit bus number overflow inside the hose -
105 	   reserve some space for bridges. */
106 	if (next_busno > 224) {
107 		next_busno = 0;
108 		need_domain_info = 1;
109 	}
110 
111 	/*
112 	 * We insert PCI resources into the iomem_resource and
113 	 * ioport_resource trees in either pci_bus_claim_resources()
114 	 * or pci_bus_assign_resources().
115 	 */
116 	if (pci_has_flag(PCI_PROBE_ONLY)) {
117 		pci_bus_claim_resources(bus);
118 	} else {
119 		pci_bus_size_bridges(bus);
120 		pci_bus_assign_resources(bus);
121 	}
122 	pci_bus_add_devices(bus);
123 }
124 
125 #ifdef CONFIG_OF
126 void pci_load_of_ranges(struct pci_controller *hose, struct device_node *node)
127 {
128 	struct of_pci_range range;
129 	struct of_pci_range_parser parser;
130 
131 	pr_info("PCI host bridge %s ranges:\n", node->full_name);
132 	hose->of_node = node;
133 
134 	if (of_pci_range_parser_init(&parser, node))
135 		return;
136 
137 	for_each_of_pci_range(&parser, &range) {
138 		struct resource *res = NULL;
139 
140 		switch (range.flags & IORESOURCE_TYPE_BITS) {
141 		case IORESOURCE_IO:
142 			pr_info("  IO 0x%016llx..0x%016llx\n",
143 				range.cpu_addr,
144 				range.cpu_addr + range.size - 1);
145 			hose->io_map_base =
146 				(unsigned long)ioremap(range.cpu_addr,
147 						       range.size);
148 			res = hose->io_resource;
149 			break;
150 		case IORESOURCE_MEM:
151 			pr_info(" MEM 0x%016llx..0x%016llx\n",
152 				range.cpu_addr,
153 				range.cpu_addr + range.size - 1);
154 			res = hose->mem_resource;
155 			break;
156 		}
157 		if (res != NULL)
158 			of_pci_range_to_resource(&range, node, res);
159 	}
160 }
161 
162 struct device_node *pcibios_get_phb_of_node(struct pci_bus *bus)
163 {
164 	struct pci_controller *hose = bus->sysdata;
165 
166 	return of_node_get(hose->of_node);
167 }
168 #endif
169 
170 static DEFINE_MUTEX(pci_scan_mutex);
171 
172 void register_pci_controller(struct pci_controller *hose)
173 {
174 	struct resource *parent;
175 
176 	parent = hose->mem_resource->parent;
177 	if (!parent)
178 		parent = &iomem_resource;
179 
180 	if (request_resource(parent, hose->mem_resource) < 0)
181 		goto out;
182 
183 	parent = hose->io_resource->parent;
184 	if (!parent)
185 		parent = &ioport_resource;
186 
187 	if (request_resource(parent, hose->io_resource) < 0) {
188 		release_resource(hose->mem_resource);
189 		goto out;
190 	}
191 
192 	INIT_LIST_HEAD(&hose->list);
193 	list_add(&hose->list, &controllers);
194 
195 	/*
196 	 * Do not panic here but later - this might happen before console init.
197 	 */
198 	if (!hose->io_map_base) {
199 		printk(KERN_WARNING
200 		       "registering PCI controller with io_map_base unset\n");
201 	}
202 
203 	/*
204 	 * Scan the bus if it is register after the PCI subsystem
205 	 * initialization.
206 	 */
207 	if (pci_initialized) {
208 		mutex_lock(&pci_scan_mutex);
209 		pcibios_scanbus(hose);
210 		mutex_unlock(&pci_scan_mutex);
211 	}
212 
213 	return;
214 
215 out:
216 	printk(KERN_WARNING
217 	       "Skipping PCI bus scan due to resource conflict\n");
218 }
219 
220 static int __init pcibios_init(void)
221 {
222 	struct pci_controller *hose;
223 
224 	/* Scan all of the recorded PCI controllers.  */
225 	list_for_each_entry(hose, &controllers, list)
226 		pcibios_scanbus(hose);
227 
228 	pci_fixup_irqs(pci_common_swizzle, pcibios_map_irq);
229 
230 	pci_initialized = 1;
231 
232 	return 0;
233 }
234 
235 subsys_initcall(pcibios_init);
236 
237 static int pcibios_enable_resources(struct pci_dev *dev, int mask)
238 {
239 	u16 cmd, old_cmd;
240 	int idx;
241 	struct resource *r;
242 
243 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
244 	old_cmd = cmd;
245 	for (idx=0; idx < PCI_NUM_RESOURCES; idx++) {
246 		/* Only set up the requested stuff */
247 		if (!(mask & (1<<idx)))
248 			continue;
249 
250 		r = &dev->resource[idx];
251 		if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
252 			continue;
253 		if ((idx == PCI_ROM_RESOURCE) &&
254 				(!(r->flags & IORESOURCE_ROM_ENABLE)))
255 			continue;
256 		if (!r->start && r->end) {
257 			printk(KERN_ERR "PCI: Device %s not available "
258 			       "because of resource collisions\n",
259 			       pci_name(dev));
260 			return -EINVAL;
261 		}
262 		if (r->flags & IORESOURCE_IO)
263 			cmd |= PCI_COMMAND_IO;
264 		if (r->flags & IORESOURCE_MEM)
265 			cmd |= PCI_COMMAND_MEMORY;
266 	}
267 	if (cmd != old_cmd) {
268 		printk("PCI: Enabling device %s (%04x -> %04x)\n",
269 		       pci_name(dev), old_cmd, cmd);
270 		pci_write_config_word(dev, PCI_COMMAND, cmd);
271 	}
272 	return 0;
273 }
274 
275 int pcibios_enable_device(struct pci_dev *dev, int mask)
276 {
277 	int err;
278 
279 	if ((err = pcibios_enable_resources(dev, mask)) < 0)
280 		return err;
281 
282 	return pcibios_plat_dev_init(dev);
283 }
284 
285 void pcibios_fixup_bus(struct pci_bus *bus)
286 {
287 	struct pci_dev *dev = bus->self;
288 
289 	if (pci_has_flag(PCI_PROBE_ONLY) && dev &&
290 	    (dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
291 		pci_read_bridge_bases(bus);
292 	}
293 }
294 
295 char * (*pcibios_plat_setup)(char *str) __initdata;
296 
297 char *__init pcibios_setup(char *str)
298 {
299 	if (pcibios_plat_setup)
300 		return pcibios_plat_setup(str);
301 	return str;
302 }
303