// SPDX-License-Identifier: GPL-2.0
/*
* From setup-res.c, by:
* Dave Rusling ([email protected])
* David Mosberger ([email protected])
* David Miller ([email protected])
* Ivan Kokshaysky ([email protected])
*/
#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/of_platform.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_alignf alignf,
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_alignf alignf,
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);
if (dev_of_node(&dev->dev) && pci_is_bridge(dev)) {
retval = of_platform_populate(dev_of_node(&dev->dev), NULL, NULL,
&dev->dev);
if (retval)
pci_err(dev, "failed to populate child OF nodes (%d)\n",
retval);
}
}
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);
static void __pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
void *userdata, bool locked)
{
struct pci_dev *dev;
struct pci_bus *bus;
struct list_head *next;
int retval;
bus = top;
if (!locked)
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;
}
if (!locked)
up_read(&pci_bus_sem);
}
/**
* 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)
{
__pci_walk_bus(top, cb, userdata, false);
}
EXPORT_SYMBOL_GPL(pci_walk_bus);
void pci_walk_bus_locked(struct pci_bus *top, int (*cb)(struct pci_dev *, void *), void *userdata)
{
lockdep_assert_held(&pci_bus_sem);
__pci_walk_bus(top, cb, userdata, true);
}
EXPORT_SYMBOL_GPL(pci_walk_bus_locked);
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);
}
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