[linux-block.git] / drivers / pci / bus.c

// SPDX-License-Identifier: GPL-2.0
/*
 * From setup-res.c, by:
 *	Dave Rusling (david.rusling@reo.mts.dec.com)
 *	David Mosberger (davidm@cs.arizona.edu)
 *	David Miller (davem@redhat.com)
 *	Ivan Kokshaysky (ink@jurassic.park.msu.ru)
 */
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/of.h>
#include <linux/proc_fs.h>
#include <linux/slab.h>

#include "pci.h"

void pci_add_resource_offset(struct list_head *resources, struct resource *res,
			     resource_size_t offset)
{
	struct resource_entry *entry;

	entry = resource_list_create_entry(res, 0);
	if (!entry) {
		pr_err("PCI: can't add host bridge window %pR\n", res);
		return;
	}

	entry->offset = offset;
	resource_list_add_tail(entry, resources);
}
EXPORT_SYMBOL(pci_add_resource_offset);

void pci_add_resource(struct list_head *resources, struct resource *res)
{
	pci_add_resource_offset(resources, res, 0);
}
EXPORT_SYMBOL(pci_add_resource);

void pci_free_resource_list(struct list_head *resources)
{
	resource_list_free(resources);
}
EXPORT_SYMBOL(pci_free_resource_list);

void pci_bus_add_resource(struct pci_bus *bus, struct resource *res,
			  unsigned int flags)
{
	struct pci_bus_resource *bus_res;

	bus_res = kzalloc(sizeof(struct pci_bus_resource), GFP_KERNEL);
	if (!bus_res) {
		dev_err(&bus->dev, "can't add %pR resource\n", res);
		return;
	}

	bus_res->res = res;
	bus_res->flags = flags;
	list_add_tail(&bus_res->list, &bus->resources);
}

struct resource *pci_bus_resource_n(const struct pci_bus *bus, int n)
{
	struct pci_bus_resource *bus_res;

	if (n < PCI_BRIDGE_RESOURCE_NUM)
		return bus->resource[n];

	n -= PCI_BRIDGE_RESOURCE_NUM;
	list_for_each_entry(bus_res, &bus->resources, list) {
		if (n-- == 0)
			return bus_res->res;
	}
	return NULL;
}
EXPORT_SYMBOL_GPL(pci_bus_resource_n);

void pci_bus_remove_resource(struct pci_bus *bus, struct resource *res)
{
	struct pci_bus_resource *bus_res, *tmp;
	int i;

	for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
		if (bus->resource[i] == res) {
			bus->resource[i] = NULL;
			return;
		}
	}

	list_for_each_entry_safe(bus_res, tmp, &bus->resources, list) {
		if (bus_res->res == res) {
			list_del(&bus_res->list);
			kfree(bus_res);
			return;
		}
	}
}

void pci_bus_remove_resources(struct pci_bus *bus)
{
	int i;
	struct pci_bus_resource *bus_res, *tmp;

	for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
		bus->resource[i] = NULL;

	list_for_each_entry_safe(bus_res, tmp, &bus->resources, list) {
		list_del(&bus_res->list);
		kfree(bus_res);
	}
}

int devm_request_pci_bus_resources(struct device *dev,
				   struct list_head *resources)
{
	struct resource_entry *win;
	struct resource *parent, *res;
	int err;

	resource_list_for_each_entry(win, resources) {
		res = win->res;
		switch (resource_type(res)) {
		case IORESOURCE_IO:
			parent = &ioport_resource;
			break;
		case IORESOURCE_MEM:
			parent = &iomem_resource;
			break;
		default:
			continue;
		}

		err = devm_request_resource(dev, parent, res);
		if (err)
			return err;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(devm_request_pci_bus_resources);

static struct pci_bus_region pci_32_bit = {0, 0xffffffffULL};
#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
static struct pci_bus_region pci_64_bit = {0,
				(pci_bus_addr_t) 0xffffffffffffffffULL};
static struct pci_bus_region pci_high = {(pci_bus_addr_t) 0x100000000ULL,
				(pci_bus_addr_t) 0xffffffffffffffffULL};
#endif

/*
 * @res contains CPU addresses.  Clip it so the corresponding bus addresses
 * on @bus are entirely within @region.  This is used to control the bus
 * addresses of resources we allocate, e.g., we may need a resource that
 * can be mapped by a 32-bit BAR.
 */
static void pci_clip_resource_to_region(struct pci_bus *bus,
					struct resource *res,
					struct pci_bus_region *region)
{
	struct pci_bus_region r;

	pcibios_resource_to_bus(bus, &r, res);
	if (r.start < region->start)
		r.start = region->start;
	if (r.end > region->end)
		r.end = region->end;

	if (r.end < r.start)
		res->end = res->start - 1;
	else
		pcibios_bus_to_resource(bus, res, &r);
}

static int pci_bus_alloc_from_region(struct pci_bus *bus, struct resource *res,
		resource_size_t size, resource_size_t align,
		resource_size_t min, unsigned long type_mask,
		resource_size_t (*alignf)(void *,
					  const struct resource *,
					  resource_size_t,
					  resource_size_t),
		void *alignf_data,
		struct pci_bus_region *region)
{
	struct resource *r, avail;
	resource_size_t max;
	int ret;

	type_mask |= IORESOURCE_TYPE_BITS;

	pci_bus_for_each_resource(bus, r) {
		resource_size_t min_used = min;

		if (!r)
			continue;

		/* type_mask must match */
		if ((res->flags ^ r->flags) & type_mask)
			continue;

		/* We cannot allocate a non-prefetching resource
		   from a pre-fetching area */
		if ((r->flags & IORESOURCE_PREFETCH) &&
		    !(res->flags & IORESOURCE_PREFETCH))
			continue;

		avail = *r;
		pci_clip_resource_to_region(bus, &avail, region);

		/*
		 * "min" is typically PCIBIOS_MIN_IO or PCIBIOS_MIN_MEM to
		 * protect badly documented motherboard resources, but if
		 * this is an already-configured bridge window, its start
		 * overrides "min".
		 */
		if (avail.start)
			min_used = avail.start;

		max = avail.end;

		/* Don't bother if available space isn't large enough */
		if (size > max - min_used + 1)
			continue;

		/* Ok, try it out.. */
		ret = allocate_resource(r, res, size, min_used, max,
					align, alignf, alignf_data);
		if (ret == 0)
			return 0;
	}
	return -ENOMEM;
}

/**
 * pci_bus_alloc_resource - allocate a resource from a parent bus
 * @bus: PCI bus
 * @res: resource to allocate
 * @size: size of resource to allocate
 * @align: alignment of resource to allocate
 * @min: minimum /proc/iomem address to allocate
 * @type_mask: IORESOURCE_* type flags
 * @alignf: resource alignment function
 * @alignf_data: data argument for resource alignment function
 *
 * Given the PCI bus a device resides on, the size, minimum address,
 * alignment and type, try to find an acceptable resource allocation
 * for a specific device resource.
 */
int pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
		resource_size_t size, resource_size_t align,
		resource_size_t min, unsigned long type_mask,
		resource_size_t (*alignf)(void *,
					  const struct resource *,
					  resource_size_t,
					  resource_size_t),
		void *alignf_data)
{
#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
	int rc;

	if (res->flags & IORESOURCE_MEM_64) {
		rc = pci_bus_alloc_from_region(bus, res, size, align, min,
					       type_mask, alignf, alignf_data,
					       &pci_high);
		if (rc == 0)
			return 0;

		return pci_bus_alloc_from_region(bus, res, size, align, min,
						 type_mask, alignf, alignf_data,
						 &pci_64_bit);
	}
#endif

	return pci_bus_alloc_from_region(bus, res, size, align, min,
					 type_mask, alignf, alignf_data,
					 &pci_32_bit);
}
EXPORT_SYMBOL(pci_bus_alloc_resource);

/*
 * The @idx resource of @dev should be a PCI-PCI bridge window.  If this
 * resource fits inside a window of an upstream bridge, do nothing.  If it
 * overlaps an upstream window but extends outside it, clip the resource so
 * it fits completely inside.
 */
bool pci_bus_clip_resource(struct pci_dev *dev, int idx)
{
	struct pci_bus *bus = dev->bus;
	struct resource *res = &dev->resource[idx];
	struct resource orig_res = *res;
	struct resource *r;

	pci_bus_for_each_resource(bus, r) {
		resource_size_t start, end;

		if (!r)
			continue;

		if (resource_type(res) != resource_type(r))
			continue;

		start = max(r->start, res->start);
		end = min(r->end, res->end);

		if (start > end)
			continue;	/* no overlap */

		if (res->start == start && res->end == end)
			return false;	/* no change */

		res->start = start;
		res->end = end;
		res->flags &= ~IORESOURCE_UNSET;
		orig_res.flags &= ~IORESOURCE_UNSET;
		pci_info(dev, "%pR clipped to %pR\n", &orig_res, res);

		return true;
	}

	return false;
}

void __weak pcibios_resource_survey_bus(struct pci_bus *bus) { }

void __weak pcibios_bus_add_device(struct pci_dev *pdev) { }

/**
 * pci_bus_add_device - start driver for a single device
 * @dev: device to add
 *
 * This adds add sysfs entries and start device drivers
 */
void pci_bus_add_device(struct pci_dev *dev)
{
	struct device_node *dn = dev->dev.of_node;
	int retval;

	/*
	 * Can not put in pci_device_add yet because resources
	 * are not assigned yet for some devices.
	 */
	pcibios_bus_add_device(dev);
	pci_fixup_device(pci_fixup_final, dev);
	if (pci_is_bridge(dev))
		of_pci_make_dev_node(dev);
	pci_create_sysfs_dev_files(dev);
	pci_proc_attach_device(dev);
	pci_bridge_d3_update(dev);

	dev->match_driver = !dn || of_device_is_available(dn);
	retval = device_attach(&dev->dev);
	if (retval < 0 && retval != -EPROBE_DEFER)
		pci_warn(dev, "device attach failed (%d)\n", retval);

	pci_dev_assign_added(dev, true);
}
EXPORT_SYMBOL_GPL(pci_bus_add_device);

/**
 * pci_bus_add_devices - start driver for PCI devices
 * @bus: bus to check for new devices
 *
 * Start driver for PCI devices and add some sysfs entries.
 */
void pci_bus_add_devices(const struct pci_bus *bus)
{
	struct pci_dev *dev;
	struct pci_bus *child;

	list_for_each_entry(dev, &bus->devices, bus_list) {
		/* Skip already-added devices */
		if (pci_dev_is_added(dev))
			continue;
		pci_bus_add_device(dev);
	}

	list_for_each_entry(dev, &bus->devices, bus_list) {
		/* Skip if device attach failed */
		if (!pci_dev_is_added(dev))
			continue;
		child = dev->subordinate;
		if (child)
			pci_bus_add_devices(child);
	}
}
EXPORT_SYMBOL(pci_bus_add_devices);

/** pci_walk_bus - walk devices on/under bus, calling callback.
 *  @top      bus whose devices should be walked
 *  @cb       callback to be called for each device found
 *  @userdata arbitrary pointer to be passed to callback.
 *
 *  Walk the given bus, including any bridged devices
 *  on buses under this bus.  Call the provided callback
 *  on each device found.
 *
 *  We check the return of @cb each time. If it returns anything
 *  other than 0, we break out.
 *
 */
void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
		  void *userdata)
{
	struct pci_dev *dev;
	struct pci_bus *bus;
	struct list_head *next;
	int retval;

	bus = top;
	down_read(&pci_bus_sem);
	next = top->devices.next;
	for (;;) {
		if (next == &bus->devices) {
			/* end of this bus, go up or finish */
			if (bus == top)
				break;
			next = bus->self->bus_list.next;
			bus = bus->self->bus;
			continue;
		}
		dev = list_entry(next, struct pci_dev, bus_list);
		if (dev->subordinate) {
			/* this is a pci-pci bridge, do its devices next */
			next = dev->subordinate->devices.next;
			bus = dev->subordinate;
		} else
			next = dev->bus_list.next;

		retval = cb(dev, userdata);
		if (retval)
			break;
	}
	up_read(&pci_bus_sem);
}
EXPORT_SYMBOL_GPL(pci_walk_bus);

struct pci_bus *pci_bus_get(struct pci_bus *bus)
{
	if (bus)
		get_device(&bus->dev);
	return bus;
}

void pci_bus_put(struct pci_bus *bus)
{
	if (bus)
		put_device(&bus->dev);
}
Commit	Line	Data
7328c8f4	1	// SPDX-License-Identifier: GPL-2.0
1da177e4	2	/*
1da177e4 LT	3	* From setup-res.c, by:
	4	* Dave Rusling (david.rusling@reo.mts.dec.com)
	5	* David Mosberger (davidm@cs.arizona.edu)
	6	* David Miller (davem@redhat.com)
	7	* Ivan Kokshaysky (ink@jurassic.park.msu.ru)
	8	*/
	9	#include <linux/module.h>
	10	#include <linux/kernel.h>
	11	#include <linux/pci.h>
	12	#include <linux/errno.h>
	13	#include <linux/ioport.h>
1a8c251c	14	#include <linux/of.h>
1da177e4	15	#include <linux/proc_fs.h>
5a0e3ad6	16	#include <linux/slab.h>
1da177e4 LT	17
	18	#include "pci.h"
	19
0efd5aab BH	20	void pci_add_resource_offset(struct list_head resources, struct resource res,
0efd5aab BH	21	resource_size_t offset)
45ca9e97	22	{
14d76b68	23	struct resource_entry *entry;
45ca9e97	24
14d76b68 JL	25	entry = resource_list_create_entry(res, 0);
14d76b68 JL	26	if (!entry) {
25da8dba	27	pr_err("PCI: can't add host bridge window %pR\n", res);
45ca9e97 BH	28	return;
	29	}
	30
14d76b68 JL	31	entry->offset = offset;
14d76b68 JL	32	resource_list_add_tail(entry, resources);
0efd5aab BH	33	}
	34	EXPORT_SYMBOL(pci_add_resource_offset);
	35
	36	void pci_add_resource(struct list_head resources, struct resource res)
	37	{
	38	pci_add_resource_offset(resources, res, 0);
45ca9e97 BH	39	}
	40	EXPORT_SYMBOL(pci_add_resource);
	41
	42	void pci_free_resource_list(struct list_head *resources)
	43	{
14d76b68	44	resource_list_free(resources);
45ca9e97 BH	45	}
	46	EXPORT_SYMBOL(pci_free_resource_list);
	47
2fe2abf8 BH	48	void pci_bus_add_resource(struct pci_bus bus, struct resource res,
	49	unsigned int flags)
	50	{
	51	struct pci_bus_resource *bus_res;
	52
	53	bus_res = kzalloc(sizeof(struct pci_bus_resource), GFP_KERNEL);
	54	if (!bus_res) {
	55	dev_err(&bus->dev, "can't add %pR resource\n", res);
	56	return;
	57	}
	58
	59	bus_res->res = res;
	60	bus_res->flags = flags;
	61	list_add_tail(&bus_res->list, &bus->resources);
	62	}
	63
	64	struct resource pci_bus_resource_n(const struct pci_bus bus, int n)
	65	{
	66	struct pci_bus_resource *bus_res;
	67
	68	if (n < PCI_BRIDGE_RESOURCE_NUM)
	69	return bus->resource[n];
	70
	71	n -= PCI_BRIDGE_RESOURCE_NUM;
	72	list_for_each_entry(bus_res, &bus->resources, list) {
	73	if (n-- == 0)
	74	return bus_res->res;
	75	}
	76	return NULL;
	77	}
	78	EXPORT_SYMBOL_GPL(pci_bus_resource_n);
	79
ab909509 NS	80	void pci_bus_remove_resource(struct pci_bus bus, struct resource res)
	81	{
	82	struct pci_bus_resource bus_res, tmp;
	83	int i;
	84
	85	for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
	86	if (bus->resource[i] == res) {
	87	bus->resource[i] = NULL;
	88	return;
	89	}
	90	}
	91
	92	list_for_each_entry_safe(bus_res, tmp, &bus->resources, list) {
	93	if (bus_res->res == res) {
	94	list_del(&bus_res->list);
	95	kfree(bus_res);
	96	return;
	97	}
	98	}
	99	}
	100
2fe2abf8 BH	101	void pci_bus_remove_resources(struct pci_bus *bus)
2fe2abf8 BH	102	{
2fe2abf8	103	int i;
817a2685	104	struct pci_bus_resource bus_res, tmp;
2fe2abf8 BH	105
2fe2abf8 BH	106	for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
7736a05a	107	bus->resource[i] = NULL;
2fe2abf8	108
817a2685 YL	109	list_for_each_entry_safe(bus_res, tmp, &bus->resources, list) {
	110	list_del(&bus_res->list);
	111	kfree(bus_res);
	112	}
2fe2abf8 BH	113	}
2fe2abf8 BH	114
950334bc BH	115	int devm_request_pci_bus_resources(struct device *dev,
	116	struct list_head *resources)
	117	{
	118	struct resource_entry *win;
	119	struct resource parent, res;
	120	int err;
	121
	122	resource_list_for_each_entry(win, resources) {
	123	res = win->res;
	124	switch (resource_type(res)) {
	125	case IORESOURCE_IO:
	126	parent = &ioport_resource;
	127	break;
	128	case IORESOURCE_MEM:
	129	parent = &iomem_resource;
	130	break;
	131	default:
	132	continue;
	133	}
	134
	135	err = devm_request_resource(dev, parent, res);
	136	if (err)
	137	return err;
	138	}
	139
	140	return 0;
	141	}
	142	EXPORT_SYMBOL_GPL(devm_request_pci_bus_resources);
	143
f75b99d5	144	static struct pci_bus_region pci_32_bit = {0, 0xffffffffULL};
8e639079	145	#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
f75b99d5	146	static struct pci_bus_region pci_64_bit = {0,
3a9ad0b4 YL	147	(pci_bus_addr_t) 0xffffffffffffffffULL};
	148	static struct pci_bus_region pci_high = {(pci_bus_addr_t) 0x100000000ULL,
	149	(pci_bus_addr_t) 0xffffffffffffffffULL};
f75b99d5 YL	150	#endif
	151
	152	/*
	153	* @res contains CPU addresses. Clip it so the corresponding bus addresses
	154	* on @bus are entirely within @region. This is used to control the bus
	155	* addresses of resources we allocate, e.g., we may need a resource that
	156	* can be mapped by a 32-bit BAR.
1da177e4	157	*/
f75b99d5 YL	158	static void pci_clip_resource_to_region(struct pci_bus *bus,
	159	struct resource *res,
	160	struct pci_bus_region *region)
	161	{
	162	struct pci_bus_region r;
	163
	164	pcibios_resource_to_bus(bus, &r, res);
	165	if (r.start < region->start)
	166	r.start = region->start;
	167	if (r.end > region->end)
	168	r.end = region->end;
	169
	170	if (r.end < r.start)
	171	res->end = res->start - 1;
	172	else
	173	pcibios_bus_to_resource(bus, res, &r);
	174	}
	175
	176	static int pci_bus_alloc_from_region(struct pci_bus bus, struct resource res,
e31dd6e4	177	resource_size_t size, resource_size_t align,
664c2848	178	resource_size_t min, unsigned long type_mask,
b26b2d49	179	resource_size_t (alignf)(void ,
3b7a17fc	180	const struct resource *,
b26b2d49 DB	181	resource_size_t,
b26b2d49 DB	182	resource_size_t),
f75b99d5 YL	183	void *alignf_data,
f75b99d5 YL	184	struct pci_bus_region *region)
1da177e4	185	{
f75b99d5 YL	186	struct resource *r, avail;
f75b99d5 YL	187	resource_size_t max;
02992064	188	int ret;
1da177e4	189
aa11fc58	190	type_mask \|= IORESOURCE_TYPE_BITS;
1da177e4	191
02992064	192	pci_bus_for_each_resource(bus, r) {
3460baa6 CB	193	resource_size_t min_used = min;
3460baa6 CB	194
6db45b76 BH	195	if (!r)
	196	continue;
	197
1da177e4 LT	198	/* type_mask must match */
	199	if ((res->flags ^ r->flags) & type_mask)
	200	continue;
	201
	202	/* We cannot allocate a non-prefetching resource
	203	from a pre-fetching area */
	204	if ((r->flags & IORESOURCE_PREFETCH) &&
	205	!(res->flags & IORESOURCE_PREFETCH))
	206	continue;
	207
f75b99d5 YL	208	avail = *r;
f75b99d5 YL	209	pci_clip_resource_to_region(bus, &avail, region);
f75b99d5	210
36e097a8 BH	211	/*
	212	* "min" is typically PCIBIOS_MIN_IO or PCIBIOS_MIN_MEM to
	213	* protect badly documented motherboard resources, but if
	214	* this is an already-configured bridge window, its start
	215	* overrides "min".
	216	*/
f75b99d5	217	if (avail.start)
3460baa6	218	min_used = avail.start;
f75b99d5 YL	219
f75b99d5 YL	220	max = avail.end;
36e097a8	221
5c5fb3c3 BH	222	/* Don't bother if available space isn't large enough */
	223	if (size > max - min_used + 1)
	224	continue;
	225
1da177e4	226	/* Ok, try it out.. */
3460baa6	227	ret = allocate_resource(r, res, size, min_used, max,
36e097a8	228	align, alignf, alignf_data);
1da177e4	229	if (ret == 0)
f75b99d5	230	return 0;
1da177e4	231	}
f75b99d5 YL	232	return -ENOMEM;
	233	}
	234
	235	/**
	236	* pci_bus_alloc_resource - allocate a resource from a parent bus
	237	* @bus: PCI bus
	238	* @res: resource to allocate
	239	* @size: size of resource to allocate
	240	* @align: alignment of resource to allocate
	241	* @min: minimum /proc/iomem address to allocate
	242	* @type_mask: IORESOURCE_* type flags
	243	* @alignf: resource alignment function
	244	* @alignf_data: data argument for resource alignment function
	245	*
	246	* Given the PCI bus a device resides on, the size, minimum address,
	247	* alignment and type, try to find an acceptable resource allocation
	248	* for a specific device resource.
	249	*/
d56dbf5b	250	int pci_bus_alloc_resource(struct pci_bus bus, struct resource res,
f75b99d5	251	resource_size_t size, resource_size_t align,
664c2848	252	resource_size_t min, unsigned long type_mask,
f75b99d5 YL	253	resource_size_t (alignf)(void ,
	254	const struct resource *,
	255	resource_size_t,
	256	resource_size_t),
	257	void *alignf_data)
	258	{
8e639079	259	#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
d56dbf5b YL	260	int rc;
	261
	262	if (res->flags & IORESOURCE_MEM_64) {
	263	rc = pci_bus_alloc_from_region(bus, res, size, align, min,
	264	type_mask, alignf, alignf_data,
	265	&pci_high);
	266	if (rc == 0)
	267	return 0;
	268
f75b99d5 YL	269	return pci_bus_alloc_from_region(bus, res, size, align, min,
	270	type_mask, alignf, alignf_data,
	271	&pci_64_bit);
1da177e4	272	}
f75b99d5 YL	273	#endif
	274
	275	return pci_bus_alloc_from_region(bus, res, size, align, min,
	276	type_mask, alignf, alignf_data,
	277	&pci_32_bit);
1da177e4	278	}
b7fe9434	279	EXPORT_SYMBOL(pci_bus_alloc_resource);
1da177e4	280
0f7e7aee YL	281	/*
	282	* The @idx resource of @dev should be a PCI-PCI bridge window. If this
	283	* resource fits inside a window of an upstream bridge, do nothing. If it
	284	* overlaps an upstream window but extends outside it, clip the resource so
	285	* it fits completely inside.
	286	*/
	287	bool pci_bus_clip_resource(struct pci_dev *dev, int idx)
	288	{
	289	struct pci_bus *bus = dev->bus;
	290	struct resource *res = &dev->resource[idx];
	291	struct resource orig_res = *res;
	292	struct resource *r;
0f7e7aee	293
02992064	294	pci_bus_for_each_resource(bus, r) {
0f7e7aee YL	295	resource_size_t start, end;
	296
	297	if (!r)
	298	continue;
	299
	300	if (resource_type(res) != resource_type(r))
	301	continue;
	302
	303	start = max(r->start, res->start);
	304	end = min(r->end, res->end);
	305
	306	if (start > end)
	307	continue; /* no overlap */
	308
	309	if (res->start == start && res->end == end)
	310	return false; /* no change */
	311
	312	res->start = start;
	313	res->end = end;
b838b39e BH	314	res->flags &= ~IORESOURCE_UNSET;
b838b39e BH	315	orig_res.flags &= ~IORESOURCE_UNSET;
34c6b710	316	pci_info(dev, "%pR clipped to %pR\n", &orig_res, res);
0f7e7aee YL	317
	318	return true;
	319	}
	320
	321	return false;
	322	}
	323
3c449ed0 YL	324	void __weak pcibios_resource_survey_bus(struct pci_bus *bus) { }
3c449ed0 YL	325
7b77061f WY	326	void __weak pcibios_bus_add_device(struct pci_dev *pdev) { }
7b77061f WY	327
1da177e4	328	/**
4f535093	329	* pci_bus_add_device - start driver for a single device
1da177e4 LT	330	* @dev: device to add
1da177e4 LT	331	*
4f535093	332	* This adds add sysfs entries and start device drivers
1da177e4	333	*/
c893d133	334	void pci_bus_add_device(struct pci_dev *dev)
1da177e4	335	{
1a8c251c	336	struct device_node *dn = dev->dev.of_node;
b19441af	337	int retval;
735bff10	338
4f535093 YL	339	/*
	340	* Can not put in pci_device_add yet because resources
	341	* are not assigned yet for some devices.
	342	*/
7b77061f	343	pcibios_bus_add_device(dev);
e253aaf0	344	pci_fixup_device(pci_fixup_final, dev);
407d1a51 LH	345	if (pci_is_bridge(dev))
407d1a51 LH	346	of_pci_make_dev_node(dev);
4f535093	347	pci_create_sysfs_dev_files(dev);
ef37702e	348	pci_proc_attach_device(dev);
1ed276a7	349	pci_bridge_d3_update(dev);
1da177e4	350
1a8c251c	351	dev->match_driver = !dn \|\| of_device_is_available(dn);
58d9a38f	352	retval = device_attach(&dev->dev);
2194bc7c	353	if (retval < 0 && retval != -EPROBE_DEFER)
7506dc79	354	pci_warn(dev, "device attach failed (%d)\n", retval);
58d9a38f	355
44bda4b7	356	pci_dev_assign_added(dev, true);
876e501a	357	}
b7fe9434	358	EXPORT_SYMBOL_GPL(pci_bus_add_device);
876e501a	359
1da177e4	360	/**
4f535093	361	* pci_bus_add_devices - start driver for PCI devices
1da177e4 LT	362	* @bus: bus to check for new devices
1da177e4 LT	363	*
4f535093	364	* Start driver for PCI devices and add some sysfs entries.
1da177e4	365	*/
c48f1670	366	void pci_bus_add_devices(const struct pci_bus *bus)
1da177e4 LT	367	{
1da177e4 LT	368	struct pci_dev *dev;
3fa16fdb	369	struct pci_bus *child;
1da177e4 LT	370
1da177e4 LT	371	list_for_each_entry(dev, &bus->devices, bus_list) {
8a1bc901	372	/* Skip already-added devices */
44bda4b7	373	if (pci_dev_is_added(dev))
1da177e4	374	continue;
c893d133	375	pci_bus_add_device(dev);
1da177e4 LT	376	}
	377
	378	list_for_each_entry(dev, &bus->devices, bus_list) {
1e398eae	379	/* Skip if device attach failed */
44bda4b7	380	if (!pci_dev_is_added(dev))
1e398eae	381	continue;
3fa16fdb	382	child = dev->subordinate;
981cf9ea JL	383	if (child)
981cf9ea JL	384	pci_bus_add_devices(child);
1da177e4 LT	385	}
1da177e4 LT	386	}
b7fe9434	387	EXPORT_SYMBOL(pci_bus_add_devices);
1da177e4	388
cecf4864 PM	389	/** pci_walk_bus - walk devices on/under bus, calling callback.
	390	* @top bus whose devices should be walked
	391	* @cb callback to be called for each device found
	392	* @userdata arbitrary pointer to be passed to callback.
	393	*
	394	* Walk the given bus, including any bridged devices
	395	* on buses under this bus. Call the provided callback
	396	* on each device found.
70298c6e ZY	397	*
	398	* We check the return of @cb each time. If it returns anything
	399	* other than 0, we break out.
	400	*
cecf4864	401	*/
70298c6e	402	void pci_walk_bus(struct pci_bus top, int (cb)(struct pci_dev , void ),
cecf4864 PM	403	void *userdata)
	404	{
	405	struct pci_dev *dev;
	406	struct pci_bus *bus;
	407	struct list_head *next;
70298c6e	408	int retval;
cecf4864 PM	409
cecf4864 PM	410	bus = top;
d71374da	411	down_read(&pci_bus_sem);
cecf4864 PM	412	next = top->devices.next;
	413	for (;;) {
	414	if (next == &bus->devices) {
	415	/* end of this bus, go up or finish */
	416	if (bus == top)
	417	break;
	418	next = bus->self->bus_list.next;
	419	bus = bus->self->bus;
	420	continue;
	421	}
	422	dev = list_entry(next, struct pci_dev, bus_list);
cecf4864 PM	423	if (dev->subordinate) {
	424	/* this is a pci-pci bridge, do its devices next */
	425	next = dev->subordinate->devices.next;
	426	bus = dev->subordinate;
	427	} else
	428	next = dev->bus_list.next;
cecf4864	429
70298c6e	430	retval = cb(dev, userdata);
70298c6e ZY	431	if (retval)
70298c6e ZY	432	break;
cecf4864	433	}
d71374da	434	up_read(&pci_bus_sem);
cecf4864	435	}
7c94def8	436	EXPORT_SYMBOL_GPL(pci_walk_bus);
cecf4864	437
fe830ef6 JL	438	struct pci_bus pci_bus_get(struct pci_bus bus)
	439	{
	440	if (bus)
	441	get_device(&bus->dev);
	442	return bus;
	443	}
fe830ef6 JL	444
	445	void pci_bus_put(struct pci_bus *bus)
	446	{
	447	if (bus)
	448	put_device(&bus->dev);
	449	}