staging: rtl8188eu: rename HalSetBrateCfg() - style
[linux/fpc-iii.git] / drivers / pci / of.c
blob1836b8ddf292e569c36a3acfad74a2ba8e843cfd
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * PCI <-> OF mapping helpers
5 * Copyright 2011 IBM Corp.
6 */
7 #define pr_fmt(fmt) "PCI: OF: " fmt
9 #include <linux/irqdomain.h>
10 #include <linux/kernel.h>
11 #include <linux/pci.h>
12 #include <linux/of.h>
13 #include <linux/of_irq.h>
14 #include <linux/of_address.h>
15 #include <linux/of_pci.h>
16 #include "pci.h"
18 void pci_set_of_node(struct pci_dev *dev)
20 if (!dev->bus->dev.of_node)
21 return;
22 dev->dev.of_node = of_pci_find_child_device(dev->bus->dev.of_node,
23 dev->devfn);
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);
36 else
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))
50 return NULL;
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);
61 return NULL;
64 struct irq_domain *pci_host_bridge_of_msi_domain(struct pci_bus *bus)
66 #ifdef CONFIG_IRQ_DOMAIN
67 struct irq_domain *d;
69 if (!bus->dev.of_node)
70 return NULL;
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);
74 if (d)
75 return d;
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);
82 if (d)
83 return d;
85 return irq_find_host(bus->dev.of_node);
86 #else
87 return NULL;
88 #endif
91 static inline int __of_pci_pci_compare(struct device_node *node,
92 unsigned int data)
94 int devfn;
96 devfn = of_pci_get_devfn(node);
97 if (devfn < 0)
98 return 0;
100 return devfn == data;
103 struct device_node *of_pci_find_child_device(struct device_node *parent,
104 unsigned int devfn)
106 struct device_node *node, *node2;
108 for_each_child_of_node(parent, node) {
109 if (__of_pci_pci_compare(node, devfn))
110 return node;
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)) {
119 of_node_put(node);
120 return node2;
125 return NULL;
127 EXPORT_SYMBOL_GPL(of_pci_find_child_device);
130 * of_pci_get_devfn() - Get device and function numbers for a device node
131 * @np: 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
136 * returned.
138 int of_pci_get_devfn(struct device_node *np)
140 u32 reg[5];
141 int error;
143 error = of_property_read_u32_array(np, "reg", reg, ARRAY_SIZE(reg));
144 if (error)
145 return error;
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
153 * @node: device node
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)
160 u32 bus_range[2];
161 int error;
163 error = of_property_read_u32_array(node, "bus-range", bus_range,
164 ARRAY_SIZE(bus_range));
165 if (error)
166 return error;
168 res->name = node->name;
169 res->start = bus_range[0];
170 res->end = bus_range[1];
171 res->flags = IORESOURCE_BUS;
173 return 0;
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)
188 u32 domain;
189 int error;
191 error = of_property_read_u32(node, "linux,pci-domain", &domain);
192 if (error)
193 return error;
195 return (u16)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)
210 u32 max_link_speed;
212 if (of_property_read_u32(node, "max-link-speed", &max_link_speed) ||
213 max_link_speed > 4)
214 return -EINVAL;
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)
226 u32 val;
227 int ret;
229 ret = of_property_read_u32(of_chosen, "linux,pci-probe-only", &val);
230 if (ret) {
231 if (ret == -ENODATA || ret == -EOVERFLOW)
232 pr_warn("linux,pci-probe-only without valid value, ignoring\n");
233 return;
236 if (val)
237 pci_add_flags(PCI_PROBE_ONLY);
238 else
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, tmp_res;
270 struct resource *bus_range;
271 struct of_pci_range range;
272 struct of_pci_range_parser parser;
273 char range_type[4];
274 int err;
276 if (io_base)
277 *io_base = (resource_size_t)OF_BAD_ADDR;
279 bus_range = devm_kzalloc(dev, sizeof(*bus_range), GFP_KERNEL);
280 if (!bus_range)
281 return -ENOMEM;
283 dev_info(dev, "host bridge %pOF ranges:\n", dev_node);
285 err = of_pci_parse_bus_range(dev_node, bus_range);
286 if (err) {
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);
292 } else {
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);
300 if (err)
301 goto failed;
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");
310 else
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)
321 continue;
323 err = of_pci_range_to_resource(&range, dev_node, &tmp_res);
324 if (err)
325 continue;
327 res = devm_kmemdup(dev, &tmp_res, sizeof(tmp_res), GFP_KERNEL);
328 if (!res) {
329 err = -ENOMEM;
330 goto failed;
333 if (resource_type(res) == IORESOURCE_IO) {
334 if (!io_base) {
335 dev_err(dev, "I/O range found for %pOF. Please provide an io_base pointer to save CPU base address\n",
336 dev_node);
337 err = -EINVAL;
338 goto failed;
340 if (*io_base != (resource_size_t)OF_BAD_ADDR)
341 dev_warn(dev, "More than one I/O resource converted for %pOF. CPU base address for old range lost!\n",
342 dev_node);
343 *io_base = range.cpu_addr;
346 pci_add_resource_offset(resources, res, res->start - range.pci_addr);
349 return 0;
351 failed:
352 pci_free_resource_list(resources);
353 return err;
355 EXPORT_SYMBOL_GPL(devm_of_pci_get_host_bridge_resources);
356 #endif /* CONFIG_OF_ADDRESS */
359 * of_pci_map_rid - Translate a requester ID through a downstream mapping.
360 * @np: root complex device node.
361 * @rid: PCI requester ID to map.
362 * @map_name: property name of the map to use.
363 * @map_mask_name: optional property name of the mask to use.
364 * @target: optional pointer to a target device node.
365 * @id_out: optional pointer to receive the translated ID.
367 * Given a PCI requester ID, look up the appropriate implementation-defined
368 * platform ID and/or the target device which receives transactions on that
369 * ID, as per the "iommu-map" and "msi-map" bindings. Either of @target or
370 * @id_out may be NULL if only the other is required. If @target points to
371 * a non-NULL device node pointer, only entries targeting that node will be
372 * matched; if it points to a NULL value, it will receive the device node of
373 * the first matching target phandle, with a reference held.
375 * Return: 0 on success or a standard error code on failure.
377 int of_pci_map_rid(struct device_node *np, u32 rid,
378 const char *map_name, const char *map_mask_name,
379 struct device_node **target, u32 *id_out)
381 u32 map_mask, masked_rid;
382 int map_len;
383 const __be32 *map = NULL;
385 if (!np || !map_name || (!target && !id_out))
386 return -EINVAL;
388 map = of_get_property(np, map_name, &map_len);
389 if (!map) {
390 if (target)
391 return -ENODEV;
392 /* Otherwise, no map implies no translation */
393 *id_out = rid;
394 return 0;
397 if (!map_len || map_len % (4 * sizeof(*map))) {
398 pr_err("%pOF: Error: Bad %s length: %d\n", np,
399 map_name, map_len);
400 return -EINVAL;
403 /* The default is to select all bits. */
404 map_mask = 0xffffffff;
407 * Can be overridden by "{iommu,msi}-map-mask" property.
408 * If of_property_read_u32() fails, the default is used.
410 if (map_mask_name)
411 of_property_read_u32(np, map_mask_name, &map_mask);
413 masked_rid = map_mask & rid;
414 for ( ; map_len > 0; map_len -= 4 * sizeof(*map), map += 4) {
415 struct device_node *phandle_node;
416 u32 rid_base = be32_to_cpup(map + 0);
417 u32 phandle = be32_to_cpup(map + 1);
418 u32 out_base = be32_to_cpup(map + 2);
419 u32 rid_len = be32_to_cpup(map + 3);
421 if (rid_base & ~map_mask) {
422 pr_err("%pOF: Invalid %s translation - %s-mask (0x%x) ignores rid-base (0x%x)\n",
423 np, map_name, map_name,
424 map_mask, rid_base);
425 return -EFAULT;
428 if (masked_rid < rid_base || masked_rid >= rid_base + rid_len)
429 continue;
431 phandle_node = of_find_node_by_phandle(phandle);
432 if (!phandle_node)
433 return -ENODEV;
435 if (target) {
436 if (*target)
437 of_node_put(phandle_node);
438 else
439 *target = phandle_node;
441 if (*target != phandle_node)
442 continue;
445 if (id_out)
446 *id_out = masked_rid - rid_base + out_base;
448 pr_debug("%pOF: %s, using mask %08x, rid-base: %08x, out-base: %08x, length: %08x, rid: %08x -> %08x\n",
449 np, map_name, map_mask, rid_base, out_base,
450 rid_len, rid, masked_rid - rid_base + out_base);
451 return 0;
454 pr_err("%pOF: Invalid %s translation - no match for rid 0x%x on %pOF\n",
455 np, map_name, rid, target && *target ? *target : NULL);
456 return -EFAULT;
459 #if IS_ENABLED(CONFIG_OF_IRQ)
461 * of_irq_parse_pci - Resolve the interrupt for a PCI device
462 * @pdev: the device whose interrupt is to be resolved
463 * @out_irq: structure of_irq filled by this function
465 * This function resolves the PCI interrupt for a given PCI device. If a
466 * device-node exists for a given pci_dev, it will use normal OF tree
467 * walking. If not, it will implement standard swizzling and walk up the
468 * PCI tree until an device-node is found, at which point it will finish
469 * resolving using the OF tree walking.
471 static int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq)
473 struct device_node *dn, *ppnode;
474 struct pci_dev *ppdev;
475 __be32 laddr[3];
476 u8 pin;
477 int rc;
480 * Check if we have a device node, if yes, fallback to standard
481 * device tree parsing
483 dn = pci_device_to_OF_node(pdev);
484 if (dn) {
485 rc = of_irq_parse_one(dn, 0, out_irq);
486 if (!rc)
487 return rc;
491 * Ok, we don't, time to have fun. Let's start by building up an
492 * interrupt spec. we assume #interrupt-cells is 1, which is standard
493 * for PCI. If you do different, then don't use that routine.
495 rc = pci_read_config_byte(pdev, PCI_INTERRUPT_PIN, &pin);
496 if (rc != 0)
497 goto err;
498 /* No pin, exit with no error message. */
499 if (pin == 0)
500 return -ENODEV;
502 /* Now we walk up the PCI tree */
503 for (;;) {
504 /* Get the pci_dev of our parent */
505 ppdev = pdev->bus->self;
507 /* Ouch, it's a host bridge... */
508 if (ppdev == NULL) {
509 ppnode = pci_bus_to_OF_node(pdev->bus);
511 /* No node for host bridge ? give up */
512 if (ppnode == NULL) {
513 rc = -EINVAL;
514 goto err;
516 } else {
517 /* We found a P2P bridge, check if it has a node */
518 ppnode = pci_device_to_OF_node(ppdev);
522 * Ok, we have found a parent with a device-node, hand over to
523 * the OF parsing code.
524 * We build a unit address from the linux device to be used for
525 * resolution. Note that we use the linux bus number which may
526 * not match your firmware bus numbering.
527 * Fortunately, in most cases, interrupt-map-mask doesn't
528 * include the bus number as part of the matching.
529 * You should still be careful about that though if you intend
530 * to rely on this function (you ship a firmware that doesn't
531 * create device nodes for all PCI devices).
533 if (ppnode)
534 break;
537 * We can only get here if we hit a P2P bridge with no node;
538 * let's do standard swizzling and try again
540 pin = pci_swizzle_interrupt_pin(pdev, pin);
541 pdev = ppdev;
544 out_irq->np = ppnode;
545 out_irq->args_count = 1;
546 out_irq->args[0] = pin;
547 laddr[0] = cpu_to_be32((pdev->bus->number << 16) | (pdev->devfn << 8));
548 laddr[1] = laddr[2] = cpu_to_be32(0);
549 rc = of_irq_parse_raw(laddr, out_irq);
550 if (rc)
551 goto err;
552 return 0;
553 err:
554 if (rc == -ENOENT) {
555 dev_warn(&pdev->dev,
556 "%s: no interrupt-map found, INTx interrupts not available\n",
557 __func__);
558 pr_warn_once("%s: possibly some PCI slots don't have level triggered interrupts capability\n",
559 __func__);
560 } else {
561 dev_err(&pdev->dev, "%s: failed with rc=%d\n", __func__, rc);
563 return rc;
567 * of_irq_parse_and_map_pci() - Decode a PCI IRQ from the device tree and map to a VIRQ
568 * @dev: The PCI device needing an IRQ
569 * @slot: PCI slot number; passed when used as map_irq callback. Unused
570 * @pin: PCI IRQ pin number; passed when used as map_irq callback. Unused
572 * @slot and @pin are unused, but included in the function so that this
573 * function can be used directly as the map_irq callback to
574 * pci_assign_irq() and struct pci_host_bridge.map_irq pointer
576 int of_irq_parse_and_map_pci(const struct pci_dev *dev, u8 slot, u8 pin)
578 struct of_phandle_args oirq;
579 int ret;
581 ret = of_irq_parse_pci(dev, &oirq);
582 if (ret)
583 return 0; /* Proper return code 0 == NO_IRQ */
585 return irq_create_of_mapping(&oirq);
587 EXPORT_SYMBOL_GPL(of_irq_parse_and_map_pci);
588 #endif /* CONFIG_OF_IRQ */
590 int pci_parse_request_of_pci_ranges(struct device *dev,
591 struct list_head *resources,
592 struct resource **bus_range)
594 int err, res_valid = 0;
595 resource_size_t iobase;
596 struct resource_entry *win, *tmp;
598 INIT_LIST_HEAD(resources);
599 err = devm_of_pci_get_host_bridge_resources(dev, 0, 0xff, resources,
600 &iobase);
601 if (err)
602 return err;
604 err = devm_request_pci_bus_resources(dev, resources);
605 if (err)
606 goto out_release_res;
608 resource_list_for_each_entry_safe(win, tmp, resources) {
609 struct resource *res = win->res;
611 switch (resource_type(res)) {
612 case IORESOURCE_IO:
613 err = devm_pci_remap_iospace(dev, res, iobase);
614 if (err) {
615 dev_warn(dev, "error %d: failed to map resource %pR\n",
616 err, res);
617 resource_list_destroy_entry(win);
619 break;
620 case IORESOURCE_MEM:
621 res_valid |= !(res->flags & IORESOURCE_PREFETCH);
622 break;
623 case IORESOURCE_BUS:
624 if (bus_range)
625 *bus_range = res;
626 break;
630 if (res_valid)
631 return 0;
633 dev_err(dev, "non-prefetchable memory resource required\n");
634 err = -EINVAL;
636 out_release_res:
637 pci_free_resource_list(resources);
638 return err;