1 // SPDX-License-Identifier: GPL-2.0+
3 * PCI <-> OF mapping helpers
5 * Copyright 2011 IBM Corp.
7 #define pr_fmt(fmt) "PCI: OF: " fmt
9 #include <linux/irqdomain.h>
10 #include <linux/kernel.h>
11 #include <linux/pci.h>
13 #include <linux/of_irq.h>
14 #include <linux/of_address.h>
15 #include <linux/of_pci.h>
18 void pci_set_of_node(struct pci_dev
*dev
)
20 if (!dev
->bus
->dev
.of_node
)
22 dev
->dev
.of_node
= of_pci_find_child_device(dev
->bus
->dev
.of_node
,
26 void pci_release_of_node(struct pci_dev
*dev
)
28 of_node_put(dev
->dev
.of_node
);
29 dev
->dev
.of_node
= NULL
;
32 void pci_set_bus_of_node(struct pci_bus
*bus
)
34 if (bus
->self
== NULL
)
35 bus
->dev
.of_node
= pcibios_get_phb_of_node(bus
);
37 bus
->dev
.of_node
= of_node_get(bus
->self
->dev
.of_node
);
40 void pci_release_bus_of_node(struct pci_bus
*bus
)
42 of_node_put(bus
->dev
.of_node
);
43 bus
->dev
.of_node
= NULL
;
46 struct device_node
* __weak
pcibios_get_phb_of_node(struct pci_bus
*bus
)
48 /* This should only be called for PHBs */
49 if (WARN_ON(bus
->self
|| bus
->parent
))
53 * Look for a node pointer in either the intermediary device we
54 * create above the root bus or its own parent. Normally only
55 * the later is populated.
57 if (bus
->bridge
->of_node
)
58 return of_node_get(bus
->bridge
->of_node
);
59 if (bus
->bridge
->parent
&& bus
->bridge
->parent
->of_node
)
60 return of_node_get(bus
->bridge
->parent
->of_node
);
64 struct irq_domain
*pci_host_bridge_of_msi_domain(struct pci_bus
*bus
)
66 #ifdef CONFIG_IRQ_DOMAIN
69 if (!bus
->dev
.of_node
)
72 /* Start looking for a phandle to an MSI controller. */
73 d
= of_msi_get_domain(&bus
->dev
, bus
->dev
.of_node
, DOMAIN_BUS_PCI_MSI
);
78 * If we don't have an msi-parent property, look for a domain
79 * directly attached to the host bridge.
81 d
= irq_find_matching_host(bus
->dev
.of_node
, DOMAIN_BUS_PCI_MSI
);
85 return irq_find_host(bus
->dev
.of_node
);
91 static inline int __of_pci_pci_compare(struct device_node
*node
,
96 devfn
= of_pci_get_devfn(node
);
100 return devfn
== data
;
103 struct device_node
*of_pci_find_child_device(struct device_node
*parent
,
106 struct device_node
*node
, *node2
;
108 for_each_child_of_node(parent
, node
) {
109 if (__of_pci_pci_compare(node
, devfn
))
112 * Some OFs create a parent node "multifunc-device" as
113 * a fake root for all functions of a multi-function
114 * device we go down them as well.
116 if (!strcmp(node
->name
, "multifunc-device")) {
117 for_each_child_of_node(node
, node2
) {
118 if (__of_pci_pci_compare(node2
, devfn
)) {
127 EXPORT_SYMBOL_GPL(of_pci_find_child_device
);
130 * of_pci_get_devfn() - Get device and function numbers for a device node
133 * Parses a standard 5-cell PCI resource and returns an 8-bit value that can
134 * be passed to the PCI_SLOT() and PCI_FUNC() macros to extract the device
135 * and function numbers respectively. On error a negative error code is
138 int of_pci_get_devfn(struct device_node
*np
)
143 error
= of_property_read_u32_array(np
, "reg", reg
, ARRAY_SIZE(reg
));
147 return (reg
[0] >> 8) & 0xff;
149 EXPORT_SYMBOL_GPL(of_pci_get_devfn
);
152 * of_pci_parse_bus_range() - parse the bus-range property of a PCI device
154 * @res: address to a struct resource to return the bus-range
156 * Returns 0 on success or a negative error-code on failure.
158 int of_pci_parse_bus_range(struct device_node
*node
, struct resource
*res
)
163 error
= of_property_read_u32_array(node
, "bus-range", bus_range
,
164 ARRAY_SIZE(bus_range
));
168 res
->name
= node
->name
;
169 res
->start
= bus_range
[0];
170 res
->end
= bus_range
[1];
171 res
->flags
= IORESOURCE_BUS
;
175 EXPORT_SYMBOL_GPL(of_pci_parse_bus_range
);
178 * This function will try to obtain the host bridge domain number by
179 * finding a property called "linux,pci-domain" of the given device node.
181 * @node: device tree node with the domain information
183 * Returns the associated domain number from DT in the range [0-0xffff], or
184 * a negative value if the required property is not found.
186 int of_get_pci_domain_nr(struct device_node
*node
)
191 error
= of_property_read_u32(node
, "linux,pci-domain", &domain
);
197 EXPORT_SYMBOL_GPL(of_get_pci_domain_nr
);
200 * This function will try to find the limitation of link speed by finding
201 * a property called "max-link-speed" of the given device node.
203 * @node: device tree node with the max link speed information
205 * Returns the associated max link speed from DT, or a negative value if the
206 * required property is not found or is invalid.
208 int of_pci_get_max_link_speed(struct device_node
*node
)
212 if (of_property_read_u32(node
, "max-link-speed", &max_link_speed
) ||
216 return max_link_speed
;
218 EXPORT_SYMBOL_GPL(of_pci_get_max_link_speed
);
221 * of_pci_check_probe_only - Setup probe only mode if linux,pci-probe-only
222 * is present and valid
224 void of_pci_check_probe_only(void)
229 ret
= of_property_read_u32(of_chosen
, "linux,pci-probe-only", &val
);
231 if (ret
== -ENODATA
|| ret
== -EOVERFLOW
)
232 pr_warn("linux,pci-probe-only without valid value, ignoring\n");
237 pci_add_flags(PCI_PROBE_ONLY
);
239 pci_clear_flags(PCI_PROBE_ONLY
);
241 pr_info("PROBE_ONLY %sabled\n", val
? "en" : "dis");
243 EXPORT_SYMBOL_GPL(of_pci_check_probe_only
);
245 #if defined(CONFIG_OF_ADDRESS)
247 * devm_of_pci_get_host_bridge_resources() - Resource-managed parsing of PCI
248 * host bridge resources from DT
249 * @dev: host bridge device
250 * @busno: bus number associated with the bridge root bus
251 * @bus_max: maximum number of buses for this bridge
252 * @resources: list where the range of resources will be added after DT parsing
253 * @io_base: pointer to a variable that will contain on return the physical
254 * address for the start of the I/O range. Can be NULL if the caller doesn't
255 * expect I/O ranges to be present in the device tree.
257 * This function will parse the "ranges" property of a PCI host bridge device
258 * node and setup the resource mapping based on its content. It is expected
259 * that the property conforms with the Power ePAPR document.
261 * It returns zero if the range parsing has been successful or a standard error
262 * value if it failed.
264 int devm_of_pci_get_host_bridge_resources(struct device
*dev
,
265 unsigned char busno
, unsigned char bus_max
,
266 struct list_head
*resources
, resource_size_t
*io_base
)
268 struct device_node
*dev_node
= dev
->of_node
;
269 struct resource
*res
;
270 struct resource
*bus_range
;
271 struct of_pci_range range
;
272 struct of_pci_range_parser parser
;
277 *io_base
= (resource_size_t
)OF_BAD_ADDR
;
279 bus_range
= devm_kzalloc(dev
, sizeof(*bus_range
), GFP_KERNEL
);
283 dev_info(dev
, "host bridge %pOF ranges:\n", dev_node
);
285 err
= of_pci_parse_bus_range(dev_node
, bus_range
);
287 bus_range
->start
= busno
;
288 bus_range
->end
= bus_max
;
289 bus_range
->flags
= IORESOURCE_BUS
;
290 dev_info(dev
, " No bus range found for %pOF, using %pR\n",
291 dev_node
, bus_range
);
293 if (bus_range
->end
> bus_range
->start
+ bus_max
)
294 bus_range
->end
= bus_range
->start
+ bus_max
;
296 pci_add_resource(resources
, bus_range
);
298 /* Check for ranges property */
299 err
= of_pci_range_parser_init(&parser
, dev_node
);
303 dev_dbg(dev
, "Parsing ranges property...\n");
304 for_each_of_pci_range(&parser
, &range
) {
305 /* Read next ranges element */
306 if ((range
.flags
& IORESOURCE_TYPE_BITS
) == IORESOURCE_IO
)
307 snprintf(range_type
, 4, " IO");
308 else if ((range
.flags
& IORESOURCE_TYPE_BITS
) == IORESOURCE_MEM
)
309 snprintf(range_type
, 4, "MEM");
311 snprintf(range_type
, 4, "err");
312 dev_info(dev
, " %s %#010llx..%#010llx -> %#010llx\n",
313 range_type
, range
.cpu_addr
,
314 range
.cpu_addr
+ range
.size
- 1, range
.pci_addr
);
317 * If we failed translation or got a zero-sized region
318 * then skip this range
320 if (range
.cpu_addr
== OF_BAD_ADDR
|| range
.size
== 0)
323 res
= devm_kzalloc(dev
, sizeof(struct resource
), GFP_KERNEL
);
329 err
= of_pci_range_to_resource(&range
, dev_node
, res
);
331 devm_kfree(dev
, res
);
335 if (resource_type(res
) == IORESOURCE_IO
) {
337 dev_err(dev
, "I/O range found for %pOF. Please provide an io_base pointer to save CPU base address\n",
342 if (*io_base
!= (resource_size_t
)OF_BAD_ADDR
)
343 dev_warn(dev
, "More than one I/O resource converted for %pOF. CPU base address for old range lost!\n",
345 *io_base
= range
.cpu_addr
;
348 pci_add_resource_offset(resources
, res
, res
->start
- range
.pci_addr
);
354 pci_free_resource_list(resources
);
357 EXPORT_SYMBOL_GPL(devm_of_pci_get_host_bridge_resources
);
358 #endif /* CONFIG_OF_ADDRESS */
361 * of_pci_map_rid - Translate a requester ID through a downstream mapping.
362 * @np: root complex device node.
363 * @rid: PCI requester ID to map.
364 * @map_name: property name of the map to use.
365 * @map_mask_name: optional property name of the mask to use.
366 * @target: optional pointer to a target device node.
367 * @id_out: optional pointer to receive the translated ID.
369 * Given a PCI requester ID, look up the appropriate implementation-defined
370 * platform ID and/or the target device which receives transactions on that
371 * ID, as per the "iommu-map" and "msi-map" bindings. Either of @target or
372 * @id_out may be NULL if only the other is required. If @target points to
373 * a non-NULL device node pointer, only entries targeting that node will be
374 * matched; if it points to a NULL value, it will receive the device node of
375 * the first matching target phandle, with a reference held.
377 * Return: 0 on success or a standard error code on failure.
379 int of_pci_map_rid(struct device_node
*np
, u32 rid
,
380 const char *map_name
, const char *map_mask_name
,
381 struct device_node
**target
, u32
*id_out
)
383 u32 map_mask
, masked_rid
;
385 const __be32
*map
= NULL
;
387 if (!np
|| !map_name
|| (!target
&& !id_out
))
390 map
= of_get_property(np
, map_name
, &map_len
);
394 /* Otherwise, no map implies no translation */
399 if (!map_len
|| map_len
% (4 * sizeof(*map
))) {
400 pr_err("%pOF: Error: Bad %s length: %d\n", np
,
405 /* The default is to select all bits. */
406 map_mask
= 0xffffffff;
409 * Can be overridden by "{iommu,msi}-map-mask" property.
410 * If of_property_read_u32() fails, the default is used.
413 of_property_read_u32(np
, map_mask_name
, &map_mask
);
415 masked_rid
= map_mask
& rid
;
416 for ( ; map_len
> 0; map_len
-= 4 * sizeof(*map
), map
+= 4) {
417 struct device_node
*phandle_node
;
418 u32 rid_base
= be32_to_cpup(map
+ 0);
419 u32 phandle
= be32_to_cpup(map
+ 1);
420 u32 out_base
= be32_to_cpup(map
+ 2);
421 u32 rid_len
= be32_to_cpup(map
+ 3);
423 if (rid_base
& ~map_mask
) {
424 pr_err("%pOF: Invalid %s translation - %s-mask (0x%x) ignores rid-base (0x%x)\n",
425 np
, map_name
, map_name
,
430 if (masked_rid
< rid_base
|| masked_rid
>= rid_base
+ rid_len
)
433 phandle_node
= of_find_node_by_phandle(phandle
);
439 of_node_put(phandle_node
);
441 *target
= phandle_node
;
443 if (*target
!= phandle_node
)
448 *id_out
= masked_rid
- rid_base
+ out_base
;
450 pr_debug("%pOF: %s, using mask %08x, rid-base: %08x, out-base: %08x, length: %08x, rid: %08x -> %08x\n",
451 np
, map_name
, map_mask
, rid_base
, out_base
,
452 rid_len
, rid
, masked_rid
- rid_base
+ out_base
);
456 pr_err("%pOF: Invalid %s translation - no match for rid 0x%x on %pOF\n",
457 np
, map_name
, rid
, target
&& *target
? *target
: NULL
);
461 #if IS_ENABLED(CONFIG_OF_IRQ)
463 * of_irq_parse_pci - Resolve the interrupt for a PCI device
464 * @pdev: the device whose interrupt is to be resolved
465 * @out_irq: structure of_irq filled by this function
467 * This function resolves the PCI interrupt for a given PCI device. If a
468 * device-node exists for a given pci_dev, it will use normal OF tree
469 * walking. If not, it will implement standard swizzling and walk up the
470 * PCI tree until an device-node is found, at which point it will finish
471 * resolving using the OF tree walking.
473 static int of_irq_parse_pci(const struct pci_dev
*pdev
, struct of_phandle_args
*out_irq
)
475 struct device_node
*dn
, *ppnode
;
476 struct pci_dev
*ppdev
;
482 * Check if we have a device node, if yes, fallback to standard
483 * device tree parsing
485 dn
= pci_device_to_OF_node(pdev
);
487 rc
= of_irq_parse_one(dn
, 0, out_irq
);
493 * Ok, we don't, time to have fun. Let's start by building up an
494 * interrupt spec. we assume #interrupt-cells is 1, which is standard
495 * for PCI. If you do different, then don't use that routine.
497 rc
= pci_read_config_byte(pdev
, PCI_INTERRUPT_PIN
, &pin
);
500 /* No pin, exit with no error message. */
504 /* Now we walk up the PCI tree */
506 /* Get the pci_dev of our parent */
507 ppdev
= pdev
->bus
->self
;
509 /* Ouch, it's a host bridge... */
511 ppnode
= pci_bus_to_OF_node(pdev
->bus
);
513 /* No node for host bridge ? give up */
514 if (ppnode
== NULL
) {
519 /* We found a P2P bridge, check if it has a node */
520 ppnode
= pci_device_to_OF_node(ppdev
);
524 * Ok, we have found a parent with a device-node, hand over to
525 * the OF parsing code.
526 * We build a unit address from the linux device to be used for
527 * resolution. Note that we use the linux bus number which may
528 * not match your firmware bus numbering.
529 * Fortunately, in most cases, interrupt-map-mask doesn't
530 * include the bus number as part of the matching.
531 * You should still be careful about that though if you intend
532 * to rely on this function (you ship a firmware that doesn't
533 * create device nodes for all PCI devices).
539 * We can only get here if we hit a P2P bridge with no node;
540 * let's do standard swizzling and try again
542 pin
= pci_swizzle_interrupt_pin(pdev
, pin
);
546 out_irq
->np
= ppnode
;
547 out_irq
->args_count
= 1;
548 out_irq
->args
[0] = pin
;
549 laddr
[0] = cpu_to_be32((pdev
->bus
->number
<< 16) | (pdev
->devfn
<< 8));
550 laddr
[1] = laddr
[2] = cpu_to_be32(0);
551 rc
= of_irq_parse_raw(laddr
, out_irq
);
558 "%s: no interrupt-map found, INTx interrupts not available\n",
560 pr_warn_once("%s: possibly some PCI slots don't have level triggered interrupts capability\n",
563 dev_err(&pdev
->dev
, "%s: failed with rc=%d\n", __func__
, rc
);
569 * of_irq_parse_and_map_pci() - Decode a PCI IRQ from the device tree and map to a VIRQ
570 * @dev: The PCI device needing an IRQ
571 * @slot: PCI slot number; passed when used as map_irq callback. Unused
572 * @pin: PCI IRQ pin number; passed when used as map_irq callback. Unused
574 * @slot and @pin are unused, but included in the function so that this
575 * function can be used directly as the map_irq callback to
576 * pci_assign_irq() and struct pci_host_bridge.map_irq pointer
578 int of_irq_parse_and_map_pci(const struct pci_dev
*dev
, u8 slot
, u8 pin
)
580 struct of_phandle_args oirq
;
583 ret
= of_irq_parse_pci(dev
, &oirq
);
585 return 0; /* Proper return code 0 == NO_IRQ */
587 return irq_create_of_mapping(&oirq
);
589 EXPORT_SYMBOL_GPL(of_irq_parse_and_map_pci
);
590 #endif /* CONFIG_OF_IRQ */
592 int pci_parse_request_of_pci_ranges(struct device
*dev
,
593 struct list_head
*resources
,
594 struct resource
**bus_range
)
596 int err
, res_valid
= 0;
597 resource_size_t iobase
;
598 struct resource_entry
*win
, *tmp
;
600 INIT_LIST_HEAD(resources
);
601 err
= devm_of_pci_get_host_bridge_resources(dev
, 0, 0xff, resources
,
606 err
= devm_request_pci_bus_resources(dev
, resources
);
608 goto out_release_res
;
610 resource_list_for_each_entry_safe(win
, tmp
, resources
) {
611 struct resource
*res
= win
->res
;
613 switch (resource_type(res
)) {
615 err
= devm_pci_remap_iospace(dev
, res
, iobase
);
617 dev_warn(dev
, "error %d: failed to map resource %pR\n",
619 resource_list_destroy_entry(win
);
623 res_valid
|= !(res
->flags
& IORESOURCE_PREFETCH
);
635 dev_err(dev
, "non-prefetchable memory resource required\n");
639 pci_free_resource_list(resources
);