diff options
Diffstat (limited to 'drivers/pci/bus.c')
-rw-r--r-- | drivers/pci/bus.c | 424 |
1 files changed, 424 insertions, 0 deletions
diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c new file mode 100644 index 000000000..87a2829df --- /dev/null +++ b/drivers/pci/bus.c @@ -0,0 +1,424 @@ +// 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/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) { + printk(KERN_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_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) +{ + int i, ret; + struct resource *r, avail; + resource_size_t max; + + type_mask |= IORESOURCE_TYPE_BITS; + + pci_bus_for_each_resource(bus, r, i) { + 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; + + /* 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; + int i; + + pci_bus_for_each_resource(bus, r, i) { + 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_printk(KERN_DEBUG, 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) +{ + 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); + pci_create_sysfs_dev_files(dev); + pci_proc_attach_device(dev); + pci_bridge_d3_update(dev); + + dev->match_driver = true; + 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; +} +EXPORT_SYMBOL(pci_bus_get); + +void pci_bus_put(struct pci_bus *bus) +{ + if (bus) + put_device(&bus->dev); +} +EXPORT_SYMBOL(pci_bus_put); |