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v3.5.6
  1/*
  2 *	drivers/pci/bus.c
  3 *
  4 * From setup-res.c, by:
  5 *	Dave Rusling (david.rusling@reo.mts.dec.com)
  6 *	David Mosberger (davidm@cs.arizona.edu)
  7 *	David Miller (davem@redhat.com)
  8 *	Ivan Kokshaysky (ink@jurassic.park.msu.ru)
  9 */
 10#include <linux/module.h>
 11#include <linux/kernel.h>
 12#include <linux/pci.h>
 13#include <linux/errno.h>
 14#include <linux/ioport.h>
 15#include <linux/proc_fs.h>
 16#include <linux/init.h>
 17#include <linux/slab.h>
 18
 19#include "pci.h"
 20
 21void pci_add_resource_offset(struct list_head *resources, struct resource *res,
 22			     resource_size_t offset)
 23{
 24	struct pci_host_bridge_window *window;
 25
 26	window = kzalloc(sizeof(struct pci_host_bridge_window), GFP_KERNEL);
 27	if (!window) {
 28		printk(KERN_ERR "PCI: can't add host bridge window %pR\n", res);
 29		return;
 30	}
 31
 32	window->res = res;
 33	window->offset = offset;
 34	list_add_tail(&window->list, resources);
 35}
 36EXPORT_SYMBOL(pci_add_resource_offset);
 37
 38void pci_add_resource(struct list_head *resources, struct resource *res)
 39{
 40	pci_add_resource_offset(resources, res, 0);
 41}
 42EXPORT_SYMBOL(pci_add_resource);
 43
 44void pci_free_resource_list(struct list_head *resources)
 45{
 46	struct pci_host_bridge_window *window, *tmp;
 47
 48	list_for_each_entry_safe(window, tmp, resources, list) {
 49		list_del(&window->list);
 50		kfree(window);
 51	}
 52}
 53EXPORT_SYMBOL(pci_free_resource_list);
 54
 55void pci_bus_add_resource(struct pci_bus *bus, struct resource *res,
 56			  unsigned int flags)
 57{
 58	struct pci_bus_resource *bus_res;
 59
 60	bus_res = kzalloc(sizeof(struct pci_bus_resource), GFP_KERNEL);
 61	if (!bus_res) {
 62		dev_err(&bus->dev, "can't add %pR resource\n", res);
 63		return;
 64	}
 65
 66	bus_res->res = res;
 67	bus_res->flags = flags;
 68	list_add_tail(&bus_res->list, &bus->resources);
 69}
 70
 71struct resource *pci_bus_resource_n(const struct pci_bus *bus, int n)
 72{
 73	struct pci_bus_resource *bus_res;
 74
 75	if (n < PCI_BRIDGE_RESOURCE_NUM)
 76		return bus->resource[n];
 77
 78	n -= PCI_BRIDGE_RESOURCE_NUM;
 79	list_for_each_entry(bus_res, &bus->resources, list) {
 80		if (n-- == 0)
 81			return bus_res->res;
 82	}
 83	return NULL;
 84}
 85EXPORT_SYMBOL_GPL(pci_bus_resource_n);
 86
 87void pci_bus_remove_resources(struct pci_bus *bus)
 88{
 89	int i;
 
 90
 91	for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
 92		bus->resource[i] = NULL;
 93
 94	pci_free_resource_list(&bus->resources);
 
 
 
 95}
 96
 97/**
 98 * pci_bus_alloc_resource - allocate a resource from a parent bus
 99 * @bus: PCI bus
100 * @res: resource to allocate
101 * @size: size of resource to allocate
102 * @align: alignment of resource to allocate
103 * @min: minimum /proc/iomem address to allocate
104 * @type_mask: IORESOURCE_* type flags
105 * @alignf: resource alignment function
106 * @alignf_data: data argument for resource alignment function
107 *
108 * Given the PCI bus a device resides on, the size, minimum address,
109 * alignment and type, try to find an acceptable resource allocation
110 * for a specific device resource.
111 */
112int
113pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
114		resource_size_t size, resource_size_t align,
115		resource_size_t min, unsigned int type_mask,
116		resource_size_t (*alignf)(void *,
117					  const struct resource *,
118					  resource_size_t,
119					  resource_size_t),
120		void *alignf_data)
 
121{
122	int i, ret = -ENOMEM;
123	struct resource *r;
124	resource_size_t max = -1;
125
126	type_mask |= IORESOURCE_IO | IORESOURCE_MEM;
127
128	/* don't allocate too high if the pref mem doesn't support 64bit*/
129	if (!(res->flags & IORESOURCE_MEM_64))
130		max = PCIBIOS_MAX_MEM_32;
131
132	pci_bus_for_each_resource(bus, r, i) {
133		if (!r)
134			continue;
135
136		/* type_mask must match */
137		if ((res->flags ^ r->flags) & type_mask)
138			continue;
139
140		/* We cannot allocate a non-prefetching resource
141		   from a pre-fetching area */
142		if ((r->flags & IORESOURCE_PREFETCH) &&
143		    !(res->flags & IORESOURCE_PREFETCH))
144			continue;
145
 
 
 
 
 
 
 
 
 
 
 
 
 
 
146		/* Ok, try it out.. */
147		ret = allocate_resource(r, res, size,
148					r->start ? : min,
149					max, align,
150					alignf, alignf_data);
151		if (ret == 0)
152			break;
153	}
154	return ret;
155}
156
157/**
158 * pci_bus_add_device - add a single device
159 * @dev: device to add
 
 
 
 
 
 
 
160 *
161 * This adds a single pci device to the global
162 * device list and adds sysfs and procfs entries
 
163 */
164int pci_bus_add_device(struct pci_dev *dev)
 
 
 
 
 
 
 
165{
166	int retval;
167	retval = device_add(&dev->dev);
168	if (retval)
169		return retval;
170
171	dev->is_added = 1;
172	pci_proc_attach_device(dev);
173	pci_create_sysfs_dev_files(dev);
174	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
175}
176
 
 
177/**
178 * pci_bus_add_child - add a child bus
179 * @bus: bus to add
180 *
181 * This adds sysfs entries for a single bus
182 */
183int pci_bus_add_child(struct pci_bus *bus)
184{
185	int retval;
186
187	if (bus->bridge)
188		bus->dev.parent = bus->bridge;
189
190	retval = device_register(&bus->dev);
191	if (retval)
192		return retval;
 
193
194	bus->is_added = 1;
 
 
195
196	/* Create legacy_io and legacy_mem files for this bus */
197	pci_create_legacy_files(bus);
198
199	return retval;
200}
201
202/**
203 * pci_bus_add_devices - insert newly discovered PCI devices
204 * @bus: bus to check for new devices
205 *
206 * Add newly discovered PCI devices (which are on the bus->devices
207 * list) to the global PCI device list, add the sysfs and procfs
208 * entries.  Where a bridge is found, add the discovered bus to
209 * the parents list of child buses, and recurse (breadth-first
210 * to be compatible with 2.4)
211 *
212 * Call hotplug for each new devices.
213 */
214void pci_bus_add_devices(const struct pci_bus *bus)
215{
216	struct pci_dev *dev;
217	struct pci_bus *child;
218	int retval;
219
220	list_for_each_entry(dev, &bus->devices, bus_list) {
221		/* Skip already-added devices */
222		if (dev->is_added)
223			continue;
224		retval = pci_bus_add_device(dev);
225		if (retval)
226			dev_err(&dev->dev, "Error adding device, continuing\n");
 
227	}
228
229	list_for_each_entry(dev, &bus->devices, bus_list) {
230		BUG_ON(!dev->is_added);
231
232		child = dev->subordinate;
233		/*
234		 * If there is an unattached subordinate bus, attach
235		 * it and then scan for unattached PCI devices.
236		 */
237		if (!child)
238			continue;
239		if (list_empty(&child->node)) {
240			down_write(&pci_bus_sem);
241			list_add_tail(&child->node, &dev->bus->children);
242			up_write(&pci_bus_sem);
243		}
244		pci_bus_add_devices(child);
245
246		/*
247		 * register the bus with sysfs as the parent is now
248		 * properly registered.
249		 */
250		if (child->is_added)
251			continue;
252		retval = pci_bus_add_child(child);
253		if (retval)
254			dev_err(&dev->dev, "Error adding bus, continuing\n");
255	}
256}
257
258void pci_enable_bridges(struct pci_bus *bus)
259{
260	struct pci_dev *dev;
261	int retval;
262
263	list_for_each_entry(dev, &bus->devices, bus_list) {
264		if (dev->subordinate) {
265			if (!pci_is_enabled(dev)) {
266				retval = pci_enable_device(dev);
267				if (retval)
268					dev_err(&dev->dev, "Error enabling bridge (%d), continuing\n", retval);
269				pci_set_master(dev);
270			}
271			pci_enable_bridges(dev->subordinate);
272		}
273	}
274}
275
276/** pci_walk_bus - walk devices on/under bus, calling callback.
277 *  @top      bus whose devices should be walked
278 *  @cb       callback to be called for each device found
279 *  @userdata arbitrary pointer to be passed to callback.
280 *
281 *  Walk the given bus, including any bridged devices
282 *  on buses under this bus.  Call the provided callback
283 *  on each device found.
284 *
285 *  We check the return of @cb each time. If it returns anything
286 *  other than 0, we break out.
287 *
288 */
289void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
290		  void *userdata)
291{
292	struct pci_dev *dev;
293	struct pci_bus *bus;
294	struct list_head *next;
295	int retval;
296
297	bus = top;
298	down_read(&pci_bus_sem);
299	next = top->devices.next;
300	for (;;) {
301		if (next == &bus->devices) {
302			/* end of this bus, go up or finish */
303			if (bus == top)
304				break;
305			next = bus->self->bus_list.next;
306			bus = bus->self->bus;
307			continue;
308		}
309		dev = list_entry(next, struct pci_dev, bus_list);
310		if (dev->subordinate) {
311			/* this is a pci-pci bridge, do its devices next */
312			next = dev->subordinate->devices.next;
313			bus = dev->subordinate;
314		} else
315			next = dev->bus_list.next;
316
317		/* Run device routines with the device locked */
318		device_lock(&dev->dev);
319		retval = cb(dev, userdata);
320		device_unlock(&dev->dev);
321		if (retval)
322			break;
323	}
324	up_read(&pci_bus_sem);
325}
326EXPORT_SYMBOL_GPL(pci_walk_bus);
327
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
328EXPORT_SYMBOL(pci_bus_alloc_resource);
329EXPORT_SYMBOL_GPL(pci_bus_add_device);
330EXPORT_SYMBOL(pci_bus_add_devices);
331EXPORT_SYMBOL(pci_enable_bridges);
v3.15
  1/*
  2 *	drivers/pci/bus.c
  3 *
  4 * From setup-res.c, by:
  5 *	Dave Rusling (david.rusling@reo.mts.dec.com)
  6 *	David Mosberger (davidm@cs.arizona.edu)
  7 *	David Miller (davem@redhat.com)
  8 *	Ivan Kokshaysky (ink@jurassic.park.msu.ru)
  9 */
 10#include <linux/module.h>
 11#include <linux/kernel.h>
 12#include <linux/pci.h>
 13#include <linux/errno.h>
 14#include <linux/ioport.h>
 15#include <linux/proc_fs.h>
 16#include <linux/init.h>
 17#include <linux/slab.h>
 18
 19#include "pci.h"
 20
 21void pci_add_resource_offset(struct list_head *resources, struct resource *res,
 22			     resource_size_t offset)
 23{
 24	struct pci_host_bridge_window *window;
 25
 26	window = kzalloc(sizeof(struct pci_host_bridge_window), GFP_KERNEL);
 27	if (!window) {
 28		printk(KERN_ERR "PCI: can't add host bridge window %pR\n", res);
 29		return;
 30	}
 31
 32	window->res = res;
 33	window->offset = offset;
 34	list_add_tail(&window->list, resources);
 35}
 36EXPORT_SYMBOL(pci_add_resource_offset);
 37
 38void pci_add_resource(struct list_head *resources, struct resource *res)
 39{
 40	pci_add_resource_offset(resources, res, 0);
 41}
 42EXPORT_SYMBOL(pci_add_resource);
 43
 44void pci_free_resource_list(struct list_head *resources)
 45{
 46	struct pci_host_bridge_window *window, *tmp;
 47
 48	list_for_each_entry_safe(window, tmp, resources, list) {
 49		list_del(&window->list);
 50		kfree(window);
 51	}
 52}
 53EXPORT_SYMBOL(pci_free_resource_list);
 54
 55void pci_bus_add_resource(struct pci_bus *bus, struct resource *res,
 56			  unsigned int flags)
 57{
 58	struct pci_bus_resource *bus_res;
 59
 60	bus_res = kzalloc(sizeof(struct pci_bus_resource), GFP_KERNEL);
 61	if (!bus_res) {
 62		dev_err(&bus->dev, "can't add %pR resource\n", res);
 63		return;
 64	}
 65
 66	bus_res->res = res;
 67	bus_res->flags = flags;
 68	list_add_tail(&bus_res->list, &bus->resources);
 69}
 70
 71struct resource *pci_bus_resource_n(const struct pci_bus *bus, int n)
 72{
 73	struct pci_bus_resource *bus_res;
 74
 75	if (n < PCI_BRIDGE_RESOURCE_NUM)
 76		return bus->resource[n];
 77
 78	n -= PCI_BRIDGE_RESOURCE_NUM;
 79	list_for_each_entry(bus_res, &bus->resources, list) {
 80		if (n-- == 0)
 81			return bus_res->res;
 82	}
 83	return NULL;
 84}
 85EXPORT_SYMBOL_GPL(pci_bus_resource_n);
 86
 87void pci_bus_remove_resources(struct pci_bus *bus)
 88{
 89	int i;
 90	struct pci_bus_resource *bus_res, *tmp;
 91
 92	for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
 93		bus->resource[i] = NULL;
 94
 95	list_for_each_entry_safe(bus_res, tmp, &bus->resources, list) {
 96		list_del(&bus_res->list);
 97		kfree(bus_res);
 98	}
 99}
100
101static struct pci_bus_region pci_32_bit = {0, 0xffffffffULL};
102#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
103static struct pci_bus_region pci_64_bit = {0,
104				(dma_addr_t) 0xffffffffffffffffULL};
105static struct pci_bus_region pci_high = {(dma_addr_t) 0x100000000ULL,
106				(dma_addr_t) 0xffffffffffffffffULL};
107#endif
108
109/*
110 * @res contains CPU addresses.  Clip it so the corresponding bus addresses
111 * on @bus are entirely within @region.  This is used to control the bus
112 * addresses of resources we allocate, e.g., we may need a resource that
113 * can be mapped by a 32-bit BAR.
 
114 */
115static void pci_clip_resource_to_region(struct pci_bus *bus,
116					struct resource *res,
117					struct pci_bus_region *region)
118{
119	struct pci_bus_region r;
120
121	pcibios_resource_to_bus(bus, &r, res);
122	if (r.start < region->start)
123		r.start = region->start;
124	if (r.end > region->end)
125		r.end = region->end;
126
127	if (r.end < r.start)
128		res->end = res->start - 1;
129	else
130		pcibios_bus_to_resource(bus, res, &r);
131}
132
133static int pci_bus_alloc_from_region(struct pci_bus *bus, struct resource *res,
134		resource_size_t size, resource_size_t align,
135		resource_size_t min, unsigned long type_mask,
136		resource_size_t (*alignf)(void *,
137					  const struct resource *,
138					  resource_size_t,
139					  resource_size_t),
140		void *alignf_data,
141		struct pci_bus_region *region)
142{
143	int i, ret;
144	struct resource *r, avail;
145	resource_size_t max;
146
147	type_mask |= IORESOURCE_TYPE_BITS;
 
 
 
 
148
149	pci_bus_for_each_resource(bus, r, i) {
150		if (!r)
151			continue;
152
153		/* type_mask must match */
154		if ((res->flags ^ r->flags) & type_mask)
155			continue;
156
157		/* We cannot allocate a non-prefetching resource
158		   from a pre-fetching area */
159		if ((r->flags & IORESOURCE_PREFETCH) &&
160		    !(res->flags & IORESOURCE_PREFETCH))
161			continue;
162
163		avail = *r;
164		pci_clip_resource_to_region(bus, &avail, region);
165
166		/*
167		 * "min" is typically PCIBIOS_MIN_IO or PCIBIOS_MIN_MEM to
168		 * protect badly documented motherboard resources, but if
169		 * this is an already-configured bridge window, its start
170		 * overrides "min".
171		 */
172		if (avail.start)
173			min = avail.start;
174
175		max = avail.end;
176
177		/* Ok, try it out.. */
178		ret = allocate_resource(r, res, size, min, max,
179					align, alignf, alignf_data);
 
 
180		if (ret == 0)
181			return 0;
182	}
183	return -ENOMEM;
184}
185
186/**
187 * pci_bus_alloc_resource - allocate a resource from a parent bus
188 * @bus: PCI bus
189 * @res: resource to allocate
190 * @size: size of resource to allocate
191 * @align: alignment of resource to allocate
192 * @min: minimum /proc/iomem address to allocate
193 * @type_mask: IORESOURCE_* type flags
194 * @alignf: resource alignment function
195 * @alignf_data: data argument for resource alignment function
196 *
197 * Given the PCI bus a device resides on, the size, minimum address,
198 * alignment and type, try to find an acceptable resource allocation
199 * for a specific device resource.
200 */
201int pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
202		resource_size_t size, resource_size_t align,
203		resource_size_t min, unsigned long type_mask,
204		resource_size_t (*alignf)(void *,
205					  const struct resource *,
206					  resource_size_t,
207					  resource_size_t),
208		void *alignf_data)
209{
210#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
211	int rc;
 
 
212
213	if (res->flags & IORESOURCE_MEM_64) {
214		rc = pci_bus_alloc_from_region(bus, res, size, align, min,
215					       type_mask, alignf, alignf_data,
216					       &pci_high);
217		if (rc == 0)
218			return 0;
219
220		return pci_bus_alloc_from_region(bus, res, size, align, min,
221						 type_mask, alignf, alignf_data,
222						 &pci_64_bit);
223	}
224#endif
225
226	return pci_bus_alloc_from_region(bus, res, size, align, min,
227					 type_mask, alignf, alignf_data,
228					 &pci_32_bit);
229}
230
231void __weak pcibios_resource_survey_bus(struct pci_bus *bus) { }
232
233/**
234 * pci_bus_add_device - start driver for a single device
235 * @dev: device to add
236 *
237 * This adds add sysfs entries and start device drivers
238 */
239int pci_bus_add_device(struct pci_dev *dev)
240{
241	int retval;
242
243	/*
244	 * Can not put in pci_device_add yet because resources
245	 * are not assigned yet for some devices.
246	 */
247	pci_fixup_device(pci_fixup_final, dev);
248	pci_create_sysfs_dev_files(dev);
249	pci_proc_attach_device(dev);
250
251	dev->match_driver = true;
252	retval = device_attach(&dev->dev);
253	WARN_ON(retval < 0);
254
255	dev->is_added = 1;
 
256
257	return 0;
258}
259
260/**
261 * pci_bus_add_devices - start driver for PCI devices
262 * @bus: bus to check for new devices
263 *
264 * Start driver for PCI devices and add some sysfs entries.
 
 
 
 
 
 
265 */
266void pci_bus_add_devices(const struct pci_bus *bus)
267{
268	struct pci_dev *dev;
269	struct pci_bus *child;
270	int retval;
271
272	list_for_each_entry(dev, &bus->devices, bus_list) {
273		/* Skip already-added devices */
274		if (dev->is_added)
275			continue;
276		retval = pci_bus_add_device(dev);
277		if (retval)
278			dev_err(&dev->dev, "Error adding device (%d)\n",
279				retval);
280	}
281
282	list_for_each_entry(dev, &bus->devices, bus_list) {
283		BUG_ON(!dev->is_added);
 
284		child = dev->subordinate;
285		if (child)
286			pci_bus_add_devices(child);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
287	}
288}
289
290/** pci_walk_bus - walk devices on/under bus, calling callback.
291 *  @top      bus whose devices should be walked
292 *  @cb       callback to be called for each device found
293 *  @userdata arbitrary pointer to be passed to callback.
294 *
295 *  Walk the given bus, including any bridged devices
296 *  on buses under this bus.  Call the provided callback
297 *  on each device found.
298 *
299 *  We check the return of @cb each time. If it returns anything
300 *  other than 0, we break out.
301 *
302 */
303void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
304		  void *userdata)
305{
306	struct pci_dev *dev;
307	struct pci_bus *bus;
308	struct list_head *next;
309	int retval;
310
311	bus = top;
312	down_read(&pci_bus_sem);
313	next = top->devices.next;
314	for (;;) {
315		if (next == &bus->devices) {
316			/* end of this bus, go up or finish */
317			if (bus == top)
318				break;
319			next = bus->self->bus_list.next;
320			bus = bus->self->bus;
321			continue;
322		}
323		dev = list_entry(next, struct pci_dev, bus_list);
324		if (dev->subordinate) {
325			/* this is a pci-pci bridge, do its devices next */
326			next = dev->subordinate->devices.next;
327			bus = dev->subordinate;
328		} else
329			next = dev->bus_list.next;
330
 
 
331		retval = cb(dev, userdata);
 
332		if (retval)
333			break;
334	}
335	up_read(&pci_bus_sem);
336}
337EXPORT_SYMBOL_GPL(pci_walk_bus);
338
339struct pci_bus *pci_bus_get(struct pci_bus *bus)
340{
341	if (bus)
342		get_device(&bus->dev);
343	return bus;
344}
345EXPORT_SYMBOL(pci_bus_get);
346
347void pci_bus_put(struct pci_bus *bus)
348{
349	if (bus)
350		put_device(&bus->dev);
351}
352EXPORT_SYMBOL(pci_bus_put);
353
354EXPORT_SYMBOL(pci_bus_alloc_resource);
355EXPORT_SYMBOL_GPL(pci_bus_add_device);
356EXPORT_SYMBOL(pci_bus_add_devices);