blob: c9d4d3a7b0fecba0d73cb5642b7be789b6f035ad [file] [log] [blame]
#define pr_fmt(fmt) "OF: PCI: " fmt
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/of_pci.h>
#include <linux/slab.h>
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)) {
return node2;
return NULL;
* 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)
unsigned int size;
const __be32 *reg;
reg = of_get_property(np, "reg", &size);
if (!reg || size < 5 * sizeof(__be32))
return -EINVAL;
return (be32_to_cpup(reg) >> 8) & 0xff;
* 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)
const __be32 *values;
int len;
values = of_get_property(node, "bus-range", &len);
if (!values || len < sizeof(*values) * 2)
return -EINVAL;
res->name = node->name;
res->start = be32_to_cpup(values++);
res->end = be32_to_cpup(values);
res->flags = IORESOURCE_BUS;
return 0;
* 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)
const __be32 *value;
int len;
u16 domain;
value = of_get_property(node, "linux,pci-domain", &len);
if (!value || len < sizeof(*value))
return -EINVAL;
domain = (u16)be32_to_cpup(value);
return domain;
* 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;
* 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");
if (val)
pr_info("PROBE_ONLY %sabled\n", val ? "en" : "dis");
#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 IO 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 %s ranges:\n", dev->full_name);
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 %s, using %pR\n",
dev->full_name, 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 */
snprintf(range_type, 4, " IO");
else if ((range.flags & IORESOURCE_TYPE_BITS) == IORESOURCE_MEM)
snprintf(range_type, 4, "MEM");
snprintf(range_type, 4, "err");
pr_info(" %s %#010llx..%#010llx -> %#010llx\n", range_type,
range.cpu_addr, range.cpu_addr + range.size - 1,
* If we failed translation or got a zero-sized region
* then skip this range
if (range.cpu_addr == OF_BAD_ADDR || range.size == 0)
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) {
if (resource_type(res) == IORESOURCE_IO) {
if (!io_base) {
pr_err("I/O range found for %s. Please provide an io_base pointer to save CPU base address\n",
err = -EINVAL;
goto conversion_failed;
if (*io_base != (resource_size_t)OF_BAD_ADDR)
pr_warn("More than one I/O resource converted for %s. CPU base address for old range lost!\n",
*io_base = range.cpu_addr;
pci_add_resource_offset(resources, res, res->start - range.pci_addr);
return 0;
resource_list_for_each_entry(window, resources)
return err;
#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("%s: Error: Bad %s length: %d\n", np->full_name,
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("%s: Invalid %s translation - %s-mask (0x%x) ignores rid-base (0x%x)\n",
np->full_name, map_name, map_name,
map_mask, rid_base);
return -EFAULT;
if (masked_rid < rid_base || masked_rid >= rid_base + rid_len)
phandle_node = of_find_node_by_phandle(phandle);
if (!phandle_node)
return -ENODEV;
if (target) {
if (*target)
*target = phandle_node;
if (*target != phandle_node)
if (id_out)
*id_out = masked_rid - rid_base + out_base;
pr_debug("%s: %s, using mask %08x, rid-base: %08x, out-base: %08x, length: %08x, rid: %08x -> %08x\n",
np->full_name, map_name, map_mask, rid_base, out_base,
rid_len, rid, *id_out);
return 0;
pr_err("%s: Invalid %s translation - no match for rid 0x%x on %s\n",
np->full_name, map_name, rid,
target && *target ? (*target)->full_name : "any target");
return -EFAULT;