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-rw-r--r--drivers/pci/bus.c449
1 files changed, 449 insertions, 0 deletions
diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
new file mode 100644
index 0000000000..9c2137dae4
--- /dev/null
+++ b/drivers/pci/bus.c
@@ -0,0 +1,449 @@
+// 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);
+}