• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 Ralf Baechle (ralf@linux-mips.org)
8  */
9 #include <linux/kernel.h>
10 #include <linux/mm.h>
11 #include <linux/bootmem.h>
12 #include <linux/init.h>
13 #include <linux/types.h>
14 #include <linux/pci.h>
15 
16 /*
17  * Indicate whether we respect the PCI setup left by the firmware.
18  *
19  * Make this long-lived  so that we know when shutting down
20  * whether we probed only or not.
21  */
22 int pci_probe_only;
23 
24 #define PCI_ASSIGN_ALL_BUSSES	1
25 
26 unsigned int pci_probe = PCI_ASSIGN_ALL_BUSSES;
27 
28 /*
29  * The PCI controller list.
30  */
31 
32 static struct pci_controller *hose_head, **hose_tail = &hose_head;
33 
34 unsigned long PCIBIOS_MIN_IO	= 0x0000;
35 unsigned long PCIBIOS_MIN_MEM	= 0;
36 
37 static int pci_initialized;
38 
39 /*
40  * We need to avoid collisions with `mirrored' VGA ports
41  * and other strange ISA hardware, so we always want the
42  * addresses to be allocated in the 0x000-0x0ff region
43  * modulo 0x400.
44  *
45  * Why? Because some silly external IO cards only decode
46  * the low 10 bits of the IO address. The 0x00-0xff region
47  * is reserved for motherboard devices that decode all 16
48  * bits, so it's ok to allocate at, say, 0x2800-0x28ff,
49  * but we want to try to avoid allocating at 0x2900-0x2bff
50  * which might have be mirrored at 0x0100-0x03ff..
51  */
52 void
pcibios_align_resource(void * data,struct resource * res,resource_size_t size,resource_size_t align)53 pcibios_align_resource(void *data, struct resource *res,
54 		       resource_size_t size, resource_size_t align)
55 {
56 	struct pci_dev *dev = data;
57 	struct pci_controller *hose = dev->sysdata;
58 	resource_size_t start = res->start;
59 
60 	if (res->flags & IORESOURCE_IO) {
61 		/* Make sure we start at our min on all hoses */
62 		if (start < PCIBIOS_MIN_IO + hose->io_resource->start)
63 			start = PCIBIOS_MIN_IO + hose->io_resource->start;
64 
65 		/*
66 		 * Put everything into 0x00-0xff region modulo 0x400
67 		 */
68 		if (start & 0x300)
69 			start = (start + 0x3ff) & ~0x3ff;
70 	} else if (res->flags & IORESOURCE_MEM) {
71 		/* Make sure we start at our min on all hoses */
72 		if (start < PCIBIOS_MIN_MEM + hose->mem_resource->start)
73 			start = PCIBIOS_MIN_MEM + hose->mem_resource->start;
74 	}
75 
76 	res->start = start;
77 }
78 
pcibios_scanbus(struct pci_controller * hose)79 static void __devinit pcibios_scanbus(struct pci_controller *hose)
80 {
81 	static int next_busno;
82 	static int need_domain_info;
83 	struct pci_bus *bus;
84 
85 	if (!hose->iommu)
86 		PCI_DMA_BUS_IS_PHYS = 1;
87 
88 	if (hose->get_busno && pci_probe_only)
89 		next_busno = (*hose->get_busno)();
90 
91 	bus = pci_scan_bus(next_busno, hose->pci_ops, hose);
92 	hose->bus = bus;
93 
94 	need_domain_info = need_domain_info || hose->index;
95 	hose->need_domain_info = need_domain_info;
96 	if (bus) {
97 		next_busno = bus->subordinate + 1;
98 		/* Don't allow 8-bit bus number overflow inside the hose -
99 		   reserve some space for bridges. */
100 		if (next_busno > 224) {
101 			next_busno = 0;
102 			need_domain_info = 1;
103 		}
104 
105 		if (!pci_probe_only) {
106 			pci_bus_size_bridges(bus);
107 			pci_bus_assign_resources(bus);
108 			pci_enable_bridges(bus);
109 		}
110 	}
111 }
112 
113 static DEFINE_MUTEX(pci_scan_mutex);
114 
register_pci_controller(struct pci_controller * hose)115 void __devinit register_pci_controller(struct pci_controller *hose)
116 {
117 	if (request_resource(&iomem_resource, hose->mem_resource) < 0)
118 		goto out;
119 	if (request_resource(&ioport_resource, hose->io_resource) < 0) {
120 		release_resource(hose->mem_resource);
121 		goto out;
122 	}
123 
124 	*hose_tail = hose;
125 	hose_tail = &hose->next;
126 
127 	/*
128 	 * Do not panic here but later - this might hapen before console init.
129 	 */
130 	if (!hose->io_map_base) {
131 		printk(KERN_WARNING
132 		       "registering PCI controller with io_map_base unset\n");
133 	}
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;
146 
147 out:
148 	printk(KERN_WARNING
149 	       "Skipping PCI bus scan due to resource conflict\n");
150 }
151 
pcibios_init(void)152 static int __init pcibios_init(void)
153 {
154 	struct pci_controller *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_fixup_irqs(pci_common_swizzle, pcibios_map_irq);
161 
162 	pci_initialized = 1;
163 
164 	return 0;
165 }
166 
167 subsys_initcall(pcibios_init);
168 
pcibios_enable_resources(struct pci_dev * dev,int mask)169 static int pcibios_enable_resources(struct pci_dev *dev, int mask)
170 {
171 	u16 cmd, old_cmd;
172 	int idx;
173 	struct resource *r;
174 
175 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
176 	old_cmd = cmd;
177 	for (idx=0; idx < PCI_NUM_RESOURCES; idx++) {
178 		/* Only set up the requested stuff */
179 		if (!(mask & (1<<idx)))
180 			continue;
181 
182 		r = &dev->resource[idx];
183 		if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
184 			continue;
185 		if ((idx == PCI_ROM_RESOURCE) &&
186 				(!(r->flags & IORESOURCE_ROM_ENABLE)))
187 			continue;
188 		if (!r->start && r->end) {
189 			printk(KERN_ERR "PCI: Device %s not available "
190 			       "because of resource collisions\n",
191 			       pci_name(dev));
192 			return -EINVAL;
193 		}
194 		if (r->flags & IORESOURCE_IO)
195 			cmd |= PCI_COMMAND_IO;
196 		if (r->flags & IORESOURCE_MEM)
197 			cmd |= PCI_COMMAND_MEMORY;
198 	}
199 	if (cmd != old_cmd) {
200 		printk("PCI: Enabling device %s (%04x -> %04x)\n",
201 		       pci_name(dev), old_cmd, cmd);
202 		pci_write_config_word(dev, PCI_COMMAND, cmd);
203 	}
204 	return 0;
205 }
206 
207 /*
208  *  If we set up a device for bus mastering, we need to check the latency
209  *  timer as certain crappy BIOSes forget to set it properly.
210  */
211 static unsigned int pcibios_max_latency = 255;
212 
pcibios_set_master(struct pci_dev * dev)213 void pcibios_set_master(struct pci_dev *dev)
214 {
215 	u8 lat;
216 	pci_read_config_byte(dev, PCI_LATENCY_TIMER, &lat);
217 	if (lat < 16)
218 		lat = (64 <= pcibios_max_latency) ? 64 : pcibios_max_latency;
219 	else if (lat > pcibios_max_latency)
220 		lat = pcibios_max_latency;
221 	else
222 		return;
223 	printk(KERN_DEBUG "PCI: Setting latency timer of device %s to %d\n",
224 	       pci_name(dev), lat);
225 	pci_write_config_byte(dev, PCI_LATENCY_TIMER, lat);
226 }
227 
pcibios_assign_all_busses(void)228 unsigned int pcibios_assign_all_busses(void)
229 {
230 	return (pci_probe & PCI_ASSIGN_ALL_BUSSES) ? 1 : 0;
231 }
232 
pcibios_enable_device(struct pci_dev * dev,int mask)233 int pcibios_enable_device(struct pci_dev *dev, int mask)
234 {
235 	int err;
236 
237 	if ((err = pcibios_enable_resources(dev, mask)) < 0)
238 		return err;
239 
240 	return pcibios_plat_dev_init(dev);
241 }
242 
pcibios_fixup_device_resources(struct pci_dev * dev,struct pci_bus * bus)243 static void pcibios_fixup_device_resources(struct pci_dev *dev,
244 	struct pci_bus *bus)
245 {
246 	/* Update device resources.  */
247 	struct pci_controller *hose = (struct pci_controller *)bus->sysdata;
248 	unsigned long offset = 0;
249 	int i;
250 
251 	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
252 		if (!dev->resource[i].start)
253 			continue;
254 		if (dev->resource[i].flags & IORESOURCE_PCI_FIXED)
255 			continue;
256 		if (dev->resource[i].flags & IORESOURCE_IO)
257 			offset = hose->io_offset;
258 		else if (dev->resource[i].flags & IORESOURCE_MEM)
259 			offset = hose->mem_offset;
260 
261 		dev->resource[i].start += offset;
262 		dev->resource[i].end += offset;
263 	}
264 }
265 
pcibios_fixup_bus(struct pci_bus * bus)266 void __devinit pcibios_fixup_bus(struct pci_bus *bus)
267 {
268 	/* Propagate hose info into the subordinate devices.  */
269 
270 	struct pci_controller *hose = bus->sysdata;
271 	struct list_head *ln;
272 	struct pci_dev *dev = bus->self;
273 
274 	if (!dev) {
275 		bus->resource[0] = hose->io_resource;
276 		bus->resource[1] = hose->mem_resource;
277 	} else if (pci_probe_only &&
278 		   (dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
279 		pci_read_bridge_bases(bus);
280 		pcibios_fixup_device_resources(dev, bus);
281 	}
282 
283 	for (ln = bus->devices.next; ln != &bus->devices; ln = ln->next) {
284 		dev = pci_dev_b(ln);
285 
286 		if ((dev->class >> 8) != PCI_CLASS_BRIDGE_PCI)
287 			pcibios_fixup_device_resources(dev, bus);
288 	}
289 }
290 
291 void __init
pcibios_update_irq(struct pci_dev * dev,int irq)292 pcibios_update_irq(struct pci_dev *dev, int irq)
293 {
294 	pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
295 }
296 
pcibios_resource_to_bus(struct pci_dev * dev,struct pci_bus_region * region,struct resource * res)297 void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
298 			 struct resource *res)
299 {
300 	struct pci_controller *hose = (struct pci_controller *)dev->sysdata;
301 	unsigned long offset = 0;
302 
303 	if (res->flags & IORESOURCE_IO)
304 		offset = hose->io_offset;
305 	else if (res->flags & IORESOURCE_MEM)
306 		offset = hose->mem_offset;
307 
308 	region->start = res->start - offset;
309 	region->end = res->end - offset;
310 }
311 
312 void __devinit
pcibios_bus_to_resource(struct pci_dev * dev,struct resource * res,struct pci_bus_region * region)313 pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
314 			struct pci_bus_region *region)
315 {
316 	struct pci_controller *hose = (struct pci_controller *)dev->sysdata;
317 	unsigned long offset = 0;
318 
319 	if (res->flags & IORESOURCE_IO)
320 		offset = hose->io_offset;
321 	else if (res->flags & IORESOURCE_MEM)
322 		offset = hose->mem_offset;
323 
324 	res->start = region->start + offset;
325 	res->end = region->end + offset;
326 }
327 
328 #ifdef CONFIG_HOTPLUG
329 EXPORT_SYMBOL(pcibios_resource_to_bus);
330 EXPORT_SYMBOL(pcibios_bus_to_resource);
331 EXPORT_SYMBOL(PCIBIOS_MIN_IO);
332 EXPORT_SYMBOL(PCIBIOS_MIN_MEM);
333 #endif
334 
pci_mmap_page_range(struct pci_dev * dev,struct vm_area_struct * vma,enum pci_mmap_state mmap_state,int write_combine)335 int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
336 			enum pci_mmap_state mmap_state, int write_combine)
337 {
338 	unsigned long prot;
339 
340 	/*
341 	 * I/O space can be accessed via normal processor loads and stores on
342 	 * this platform but for now we elect not to do this and portable
343 	 * drivers should not do this anyway.
344 	 */
345 	if (mmap_state == pci_mmap_io)
346 		return -EINVAL;
347 
348 	/*
349 	 * Ignore write-combine; for now only return uncached mappings.
350 	 */
351 	prot = pgprot_val(vma->vm_page_prot);
352 	prot = (prot & ~_CACHE_MASK) | _CACHE_UNCACHED;
353 	vma->vm_page_prot = __pgprot(prot);
354 
355 	return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
356 		vma->vm_end - vma->vm_start, vma->vm_page_prot);
357 }
358 
359 char * (*pcibios_plat_setup)(char *str) __devinitdata;
360 
pcibios_setup(char * str)361 char *__devinit pcibios_setup(char *str)
362 {
363 	if (pcibios_plat_setup)
364 		return pcibios_plat_setup(str);
365 	return str;
366 }
367