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);
+}