1 files changed, 564 insertions, 7 deletions

diff --git a/drivers/pci/of.c b/drivers/pci/of.c
index e112da11630e..a28355c273ae 100644
--- a/drivers/pci/of.c
+++ b/drivers/pci/of.c
@@ -1,19 +1,17 @@
+// SPDX-License-Identifier: GPL-2.0+
 /*
  * PCI <-> OF mapping helpers
  *
  * Copyright 2011 IBM Corp.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
  */
+#define pr_fmt(fmt)	"PCI: OF: " fmt
 
 #include <linux/irqdomain.h>
 #include <linux/kernel.h>
 #include <linux/pci.h>
 #include <linux/of.h>
 #include <linux/of_irq.h>
+#include <linux/of_address.h>
 #include <linux/of_pci.h>
 #include "pci.h"
 
@@ -51,8 +49,9 @@ struct device_node * __weak pcibios_get_phb_of_node(struct pci_bus *bus)
 	if (WARN_ON(bus->self || bus->parent))
 		return NULL;
 
-	/* Look for a node pointer in either the intermediary device we
-	 * create above the root bus or it's own parent. Normally only
+	/*
+	 * Look for a node pointer in either the intermediary device we
+	 * create above the root bus or its own parent. Normally only
 	 * the later is populated.
 	 */
 	if (bus->bridge->of_node)
@@ -88,3 +87,561 @@ struct irq_domain *pci_host_bridge_of_msi_domain(struct pci_bus *bus)
 	return NULL;
 #endif
 }
+
+static inline int __of_pci_pci_compare(struct device_node *node,
+				       unsigned int data)
+{
+	int devfn;
+
+	devfn = of_pci_get_devfn(node);
+	if (devfn < 0)
+		return 0;
+
+	return devfn == data;
+}
+
+struct device_node *of_pci_find_child_device(struct device_node *parent,
+					     unsigned int devfn)
+{
+	struct device_node *node, *node2;
+
+	for_each_child_of_node(parent, node) {
+		if (__of_pci_pci_compare(node, devfn))
+			return node;
+		/*
+		 * Some OFs create a parent node "multifunc-device" as
+		 * a fake root for all functions of a multi-function
+		 * device we go down them as well.
+		 */
+		if (!strcmp(node->name, "multifunc-device")) {
+			for_each_child_of_node(node, node2) {
+				if (__of_pci_pci_compare(node2, devfn)) {
+					of_node_put(node);
+					return node2;
+				}
+			}
+		}
+	}
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(of_pci_find_child_device);
+
+/**
+ * of_pci_get_devfn() - Get device and function numbers for a device node
+ * @np: device node
+ *
+ * Parses a standard 5-cell PCI resource and returns an 8-bit value that can
+ * be passed to the PCI_SLOT() and PCI_FUNC() macros to extract the device
+ * and function numbers respectively. On error a negative error code is
+ * returned.
+ */
+int of_pci_get_devfn(struct device_node *np)
+{
+	u32 reg[5];
+	int error;
+
+	error = of_property_read_u32_array(np, "reg", reg, ARRAY_SIZE(reg));
+	if (error)
+		return error;
+
+	return (reg[0] >> 8) & 0xff;
+}
+EXPORT_SYMBOL_GPL(of_pci_get_devfn);
+
+/**
+ * of_pci_parse_bus_range() - parse the bus-range property of a PCI device
+ * @node: device node
+ * @res: address to a struct resource to return the bus-range
+ *
+ * Returns 0 on success or a negative error-code on failure.
+ */
+int of_pci_parse_bus_range(struct device_node *node, struct resource *res)
+{
+	u32 bus_range[2];
+	int error;
+
+	error = of_property_read_u32_array(node, "bus-range", bus_range,
+					   ARRAY_SIZE(bus_range));
+	if (error)
+		return error;
+
+	res->name = node->name;
+	res->start = bus_range[0];
+	res->end = bus_range[1];
+	res->flags = IORESOURCE_BUS;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(of_pci_parse_bus_range);
+
+/**
+ * This function will try to obtain the host bridge domain number by
+ * finding a property called "linux,pci-domain" of the given device node.
+ *
+ * @node: device tree node with the domain information
+ *
+ * Returns the associated domain number from DT in the range [0-0xffff], or
+ * a negative value if the required property is not found.
+ */
+int of_get_pci_domain_nr(struct device_node *node)
+{
+	u32 domain;
+	int error;
+
+	error = of_property_read_u32(node, "linux,pci-domain", &domain);
+	if (error)
+		return error;
+
+	return (u16)domain;
+}
+EXPORT_SYMBOL_GPL(of_get_pci_domain_nr);
+
+/**
+ * This function will try to find the limitation of link speed by finding
+ * a property called "max-link-speed" of the given device node.
+ *
+ * @node: device tree node with the max link speed information
+ *
+ * Returns the associated max link speed from DT, or a negative value if the
+ * required property is not found or is invalid.
+ */
+int of_pci_get_max_link_speed(struct device_node *node)
+{
+	u32 max_link_speed;
+
+	if (of_property_read_u32(node, "max-link-speed", &max_link_speed) ||
+	    max_link_speed > 4)
+		return -EINVAL;
+
+	return max_link_speed;
+}
+EXPORT_SYMBOL_GPL(of_pci_get_max_link_speed);
+
+/**
+ * of_pci_check_probe_only - Setup probe only mode if linux,pci-probe-only
+ *                           is present and valid
+ */
+void of_pci_check_probe_only(void)
+{
+	u32 val;
+	int ret;
+
+	ret = of_property_read_u32(of_chosen, "linux,pci-probe-only", &val);
+	if (ret) {
+		if (ret == -ENODATA || ret == -EOVERFLOW)
+			pr_warn("linux,pci-probe-only without valid value, ignoring\n");
+		return;
+	}
+
+	if (val)
+		pci_add_flags(PCI_PROBE_ONLY);
+	else
+		pci_clear_flags(PCI_PROBE_ONLY);
+
+	pr_info("PROBE_ONLY %sabled\n", val ? "en" : "dis");
+}
+EXPORT_SYMBOL_GPL(of_pci_check_probe_only);
+
+#if defined(CONFIG_OF_ADDRESS)
+/**
+ * of_pci_get_host_bridge_resources - Parse PCI host bridge resources from DT
+ * @dev: device node of the host bridge having the range property
+ * @busno: bus number associated with the bridge root bus
+ * @bus_max: maximum number of buses for this bridge
+ * @resources: list where the range of resources will be added after DT parsing
+ * @io_base: pointer to a variable that will contain on return the physical
+ * address for the start of the I/O range. Can be NULL if the caller doesn't
+ * expect I/O ranges to be present in the device tree.
+ *
+ * It is the caller's job to free the @resources list.
+ *
+ * This function will parse the "ranges" property of a PCI host bridge device
+ * node and setup the resource mapping based on its content. It is expected
+ * that the property conforms with the Power ePAPR document.
+ *
+ * It returns zero if the range parsing has been successful or a standard error
+ * value if it failed.
+ */
+int of_pci_get_host_bridge_resources(struct device_node *dev,
+			unsigned char busno, unsigned char bus_max,
+			struct list_head *resources, resource_size_t *io_base)
+{
+	struct resource_entry *window;
+	struct resource *res;
+	struct resource *bus_range;
+	struct of_pci_range range;
+	struct of_pci_range_parser parser;
+	char range_type[4];
+	int err;
+
+	if (io_base)
+		*io_base = (resource_size_t)OF_BAD_ADDR;
+
+	bus_range = kzalloc(sizeof(*bus_range), GFP_KERNEL);
+	if (!bus_range)
+		return -ENOMEM;
+
+	pr_info("host bridge %pOF ranges:\n", dev);
+
+	err = of_pci_parse_bus_range(dev, bus_range);
+	if (err) {
+		bus_range->start = busno;
+		bus_range->end = bus_max;
+		bus_range->flags = IORESOURCE_BUS;
+		pr_info("  No bus range found for %pOF, using %pR\n",
+			dev, bus_range);
+	} else {
+		if (bus_range->end > bus_range->start + bus_max)
+			bus_range->end = bus_range->start + bus_max;
+	}
+	pci_add_resource(resources, bus_range);
+
+	/* Check for ranges property */
+	err = of_pci_range_parser_init(&parser, dev);
+	if (err)
+		goto parse_failed;
+
+	pr_debug("Parsing ranges property...\n");
+	for_each_of_pci_range(&parser, &range) {
+		/* Read next ranges element */
+		if ((range.flags & IORESOURCE_TYPE_BITS) == IORESOURCE_IO)
+			snprintf(range_type, 4, " IO");
+		else if ((range.flags & IORESOURCE_TYPE_BITS) == IORESOURCE_MEM)
+			snprintf(range_type, 4, "MEM");
+		else
+			snprintf(range_type, 4, "err");
+		pr_info("  %s %#010llx..%#010llx -> %#010llx\n", range_type,
+			range.cpu_addr, range.cpu_addr + range.size - 1,
+			range.pci_addr);
+
+		/*
+		 * If we failed translation or got a zero-sized region
+		 * then skip this range
+		 */
+		if (range.cpu_addr == OF_BAD_ADDR || range.size == 0)
+			continue;
+
+		res = kzalloc(sizeof(struct resource), GFP_KERNEL);
+		if (!res) {
+			err = -ENOMEM;
+			goto parse_failed;
+		}
+
+		err = of_pci_range_to_resource(&range, dev, res);
+		if (err) {
+			kfree(res);
+			continue;
+		}
+
+		if (resource_type(res) == IORESOURCE_IO) {
+			if (!io_base) {
+				pr_err("I/O range found for %pOF. Please provide an io_base pointer to save CPU base address\n",
+					dev);
+				err = -EINVAL;
+				goto conversion_failed;
+			}
+			if (*io_base != (resource_size_t)OF_BAD_ADDR)
+				pr_warn("More than one I/O resource converted for %pOF. CPU base address for old range lost!\n",
+					dev);
+			*io_base = range.cpu_addr;
+		}
+
+		pci_add_resource_offset(resources, res,	res->start - range.pci_addr);
+	}
+
+	return 0;
+
+conversion_failed:
+	kfree(res);
+parse_failed:
+	resource_list_for_each_entry(window, resources)
+		kfree(window->res);
+	pci_free_resource_list(resources);
+	return err;
+}
+EXPORT_SYMBOL_GPL(of_pci_get_host_bridge_resources);
+#endif /* CONFIG_OF_ADDRESS */
+
+/**
+ * of_pci_map_rid - Translate a requester ID through a downstream mapping.
+ * @np: root complex device node.
+ * @rid: PCI requester ID to map.
+ * @map_name: property name of the map to use.
+ * @map_mask_name: optional property name of the mask to use.
+ * @target: optional pointer to a target device node.
+ * @id_out: optional pointer to receive the translated ID.
+ *
+ * Given a PCI requester ID, look up the appropriate implementation-defined
+ * platform ID and/or the target device which receives transactions on that
+ * ID, as per the "iommu-map" and "msi-map" bindings. Either of @target or
+ * @id_out may be NULL if only the other is required. If @target points to
+ * a non-NULL device node pointer, only entries targeting that node will be
+ * matched; if it points to a NULL value, it will receive the device node of
+ * the first matching target phandle, with a reference held.
+ *
+ * Return: 0 on success or a standard error code on failure.
+ */
+int of_pci_map_rid(struct device_node *np, u32 rid,
+		   const char *map_name, const char *map_mask_name,
+		   struct device_node **target, u32 *id_out)
+{
+	u32 map_mask, masked_rid;
+	int map_len;
+	const __be32 *map = NULL;
+
+	if (!np || !map_name || (!target && !id_out))
+		return -EINVAL;
+
+	map = of_get_property(np, map_name, &map_len);
+	if (!map) {
+		if (target)
+			return -ENODEV;
+		/* Otherwise, no map implies no translation */
+		*id_out = rid;
+		return 0;
+	}
+
+	if (!map_len || map_len % (4 * sizeof(*map))) {
+		pr_err("%pOF: Error: Bad %s length: %d\n", np,
+			map_name, map_len);
+		return -EINVAL;
+	}
+
+	/* The default is to select all bits. */
+	map_mask = 0xffffffff;
+
+	/*
+	 * Can be overridden by "{iommu,msi}-map-mask" property.
+	 * If of_property_read_u32() fails, the default is used.
+	 */
+	if (map_mask_name)
+		of_property_read_u32(np, map_mask_name, &map_mask);
+
+	masked_rid = map_mask & rid;
+	for ( ; map_len > 0; map_len -= 4 * sizeof(*map), map += 4) {
+		struct device_node *phandle_node;
+		u32 rid_base = be32_to_cpup(map + 0);
+		u32 phandle = be32_to_cpup(map + 1);
+		u32 out_base = be32_to_cpup(map + 2);
+		u32 rid_len = be32_to_cpup(map + 3);
+
+		if (rid_base & ~map_mask) {
+			pr_err("%pOF: Invalid %s translation - %s-mask (0x%x) ignores rid-base (0x%x)\n",
+				np, map_name, map_name,
+				map_mask, rid_base);
+			return -EFAULT;
+		}
+
+		if (masked_rid < rid_base || masked_rid >= rid_base + rid_len)
+			continue;
+
+		phandle_node = of_find_node_by_phandle(phandle);
+		if (!phandle_node)
+			return -ENODEV;
+
+		if (target) {
+			if (*target)
+				of_node_put(phandle_node);
+			else
+				*target = phandle_node;
+
+			if (*target != phandle_node)
+				continue;
+		}
+
+		if (id_out)
+			*id_out = masked_rid - rid_base + out_base;
+
+		pr_debug("%pOF: %s, using mask %08x, rid-base: %08x, out-base: %08x, length: %08x, rid: %08x -> %08x\n",
+			np, map_name, map_mask, rid_base, out_base,
+			rid_len, rid, masked_rid - rid_base + out_base);
+		return 0;
+	}
+
+	pr_err("%pOF: Invalid %s translation - no match for rid 0x%x on %pOF\n",
+		np, map_name, rid, target && *target ? *target : NULL);
+	return -EFAULT;
+}
+
+#if IS_ENABLED(CONFIG_OF_IRQ)
+/**
+ * of_irq_parse_pci - Resolve the interrupt for a PCI device
+ * @pdev:       the device whose interrupt is to be resolved
+ * @out_irq:    structure of_irq filled by this function
+ *
+ * This function resolves the PCI interrupt for a given PCI device. If a
+ * device-node exists for a given pci_dev, it will use normal OF tree
+ * walking. If not, it will implement standard swizzling and walk up the
+ * PCI tree until an device-node is found, at which point it will finish
+ * resolving using the OF tree walking.
+ */
+static int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq)
+{
+	struct device_node *dn, *ppnode;
+	struct pci_dev *ppdev;
+	__be32 laddr[3];
+	u8 pin;
+	int rc;
+
+	/*
+	 * Check if we have a device node, if yes, fallback to standard
+	 * device tree parsing
+	 */
+	dn = pci_device_to_OF_node(pdev);
+	if (dn) {
+		rc = of_irq_parse_one(dn, 0, out_irq);
+		if (!rc)
+			return rc;
+	}
+
+	/*
+	 * Ok, we don't, time to have fun. Let's start by building up an
+	 * interrupt spec.  we assume #interrupt-cells is 1, which is standard
+	 * for PCI. If you do different, then don't use that routine.
+	 */
+	rc = pci_read_config_byte(pdev, PCI_INTERRUPT_PIN, &pin);
+	if (rc != 0)
+		goto err;
+	/* No pin, exit with no error message. */
+	if (pin == 0)
+		return -ENODEV;
+
+	/* Now we walk up the PCI tree */
+	for (;;) {
+		/* Get the pci_dev of our parent */
+		ppdev = pdev->bus->self;
+
+		/* Ouch, it's a host bridge... */
+		if (ppdev == NULL) {
+			ppnode = pci_bus_to_OF_node(pdev->bus);
+
+			/* No node for host bridge ? give up */
+			if (ppnode == NULL) {
+				rc = -EINVAL;
+				goto err;
+			}
+		} else {
+			/* We found a P2P bridge, check if it has a node */
+			ppnode = pci_device_to_OF_node(ppdev);
+		}
+
+		/*
+		 * Ok, we have found a parent with a device-node, hand over to
+		 * the OF parsing code.
+		 * We build a unit address from the linux device to be used for
+		 * resolution. Note that we use the linux bus number which may
+		 * not match your firmware bus numbering.
+		 * Fortunately, in most cases, interrupt-map-mask doesn't
+		 * include the bus number as part of the matching.
+		 * You should still be careful about that though if you intend
+		 * to rely on this function (you ship a firmware that doesn't
+		 * create device nodes for all PCI devices).
+		 */
+		if (ppnode)
+			break;
+
+		/*
+		 * We can only get here if we hit a P2P bridge with no node;
+		 * let's do standard swizzling and try again
+		 */
+		pin = pci_swizzle_interrupt_pin(pdev, pin);
+		pdev = ppdev;
+	}
+
+	out_irq->np = ppnode;
+	out_irq->args_count = 1;
+	out_irq->args[0] = pin;
+	laddr[0] = cpu_to_be32((pdev->bus->number << 16) | (pdev->devfn << 8));
+	laddr[1] = laddr[2] = cpu_to_be32(0);
+	rc = of_irq_parse_raw(laddr, out_irq);
+	if (rc)
+		goto err;
+	return 0;
+err:
+	if (rc == -ENOENT) {
+		dev_warn(&pdev->dev,
+			"%s: no interrupt-map found, INTx interrupts not available\n",
+			__func__);
+		pr_warn_once("%s: possibly some PCI slots don't have level triggered interrupts capability\n",
+			__func__);
+	} else {
+		dev_err(&pdev->dev, "%s: failed with rc=%d\n", __func__, rc);
+	}
+	return rc;
+}
+
+/**
+ * of_irq_parse_and_map_pci() - Decode a PCI IRQ from the device tree and map to a VIRQ
+ * @dev: The PCI device needing an IRQ
+ * @slot: PCI slot number; passed when used as map_irq callback. Unused
+ * @pin: PCI IRQ pin number; passed when used as map_irq callback. Unused
+ *
+ * @slot and @pin are unused, but included in the function so that this
+ * function can be used directly as the map_irq callback to
+ * pci_assign_irq() and struct pci_host_bridge.map_irq pointer
+ */
+int of_irq_parse_and_map_pci(const struct pci_dev *dev, u8 slot, u8 pin)
+{
+	struct of_phandle_args oirq;
+	int ret;
+
+	ret = of_irq_parse_pci(dev, &oirq);
+	if (ret)
+		return 0; /* Proper return code 0 == NO_IRQ */
+
+	return irq_create_of_mapping(&oirq);
+}
+EXPORT_SYMBOL_GPL(of_irq_parse_and_map_pci);
+#endif	/* CONFIG_OF_IRQ */
+
+int pci_parse_request_of_pci_ranges(struct device *dev,
+				    struct list_head *resources,
+				    struct resource **bus_range)
+{
+	int err, res_valid = 0;
+	struct device_node *np = dev->of_node;
+	resource_size_t iobase;
+	struct resource_entry *win, *tmp;
+
+	INIT_LIST_HEAD(resources);
+	err = of_pci_get_host_bridge_resources(np, 0, 0xff, resources, &iobase);
+	if (err)
+		return err;
+
+	err = devm_request_pci_bus_resources(dev, resources);
+	if (err)
+		goto out_release_res;
+
+	resource_list_for_each_entry_safe(win, tmp, resources) {
+		struct resource *res = win->res;
+
+		switch (resource_type(res)) {
+		case IORESOURCE_IO:
+			err = pci_remap_iospace(res, iobase);
+			if (err) {
+				dev_warn(dev, "error %d: failed to map resource %pR\n",
+					 err, res);
+				resource_list_destroy_entry(win);
+			}
+			break;
+		case IORESOURCE_MEM:
+			res_valid |= !(res->flags & IORESOURCE_PREFETCH);
+			break;
+		case IORESOURCE_BUS:
+			if (bus_range)
+				*bus_range = res;
+			break;
+		}
+	}
+
+	if (res_valid)
+		return 0;
+
+	dev_err(dev, "non-prefetchable memory resource required\n");
+	err = -EINVAL;
+
+ out_release_res:
+	pci_free_resource_list(resources);
+	return err;
+}
+