1 // SPDX-License-Identifier: GPL-2.0-or-later
5 * Copyright (C) 2001 Todd Inglett, IBM Corporation
7 * PCI manipulation via device_nodes.
9 #include <linux/kernel.h>
10 #include <linux/pci.h>
11 #include <linux/string.h>
12 #include <linux/export.h>
13 #include <linux/init.h>
14 #include <linux/gfp.h>
18 #include <asm/pci-bridge.h>
19 #include <asm/ppc-pci.h>
20 #include <asm/firmware.h>
24 * The function is used to find the firmware data of one
25 * specific PCI device, which is attached to the indicated
26 * PCI bus. For VFs, their firmware data is linked to that
27 * one of PF's bridge. For other devices, their firmware
28 * data is linked to that of their bridge.
30 static struct pci_dn *pci_bus_to_pdn(struct pci_bus *bus)
33 struct device_node *dn;
37 * We probably have virtual bus which doesn't
38 * have associated bridge.
42 if (pci_is_root_bus(pbus) || pbus->self)
49 * Except virtual bus, all PCI buses should
52 dn = pci_bus_to_OF_node(pbus);
53 pdn = dn ? PCI_DN(dn) : NULL;
58 struct pci_dn *pci_get_pdn_by_devfn(struct pci_bus *bus,
61 struct device_node *dn = NULL;
62 struct pci_dn *parent, *pdn;
63 struct pci_dev *pdev = NULL;
65 /* Fast path: fetch from PCI device */
66 list_for_each_entry(pdev, &bus->devices, bus_list) {
67 if (pdev->devfn == devfn) {
68 if (pdev->dev.archdata.pci_data)
69 return pdev->dev.archdata.pci_data;
71 dn = pci_device_to_OF_node(pdev);
76 /* Fast path: fetch from device node */
77 pdn = dn ? PCI_DN(dn) : NULL;
81 /* Slow path: fetch from firmware data hierarchy */
82 parent = pci_bus_to_pdn(bus);
86 list_for_each_entry(pdn, &parent->child_list, list) {
87 if (pdn->busno == bus->number &&
95 struct pci_dn *pci_get_pdn(struct pci_dev *pdev)
97 struct device_node *dn;
98 struct pci_dn *parent, *pdn;
100 /* Search device directly */
101 if (pdev->dev.archdata.pci_data)
102 return pdev->dev.archdata.pci_data;
104 /* Check device node */
105 dn = pci_device_to_OF_node(pdev);
106 pdn = dn ? PCI_DN(dn) : NULL;
111 * VFs don't have device nodes. We hook their
112 * firmware data to PF's bridge.
114 parent = pci_bus_to_pdn(pdev->bus);
118 list_for_each_entry(pdn, &parent->child_list, list) {
119 if (pdn->busno == pdev->bus->number &&
120 pdn->devfn == pdev->devfn)
128 static struct eeh_dev *eeh_dev_init(struct pci_dn *pdn)
130 struct eeh_dev *edev;
132 /* Allocate EEH device */
133 edev = kzalloc(sizeof(*edev), GFP_KERNEL);
137 /* Associate EEH device with OF node */
140 edev->bdfn = (pdn->busno << 8) | pdn->devfn;
141 edev->controller = pdn->phb;
145 #endif /* CONFIG_EEH */
147 #ifdef CONFIG_PCI_IOV
148 static struct pci_dn *add_one_sriov_vf_pdn(struct pci_dn *parent,
149 int busno, int devfn)
153 /* Except PHB, we always have the parent */
157 pdn = kzalloc(sizeof(*pdn), GFP_KERNEL);
161 pdn->phb = parent->phb;
162 pdn->parent = parent;
165 pdn->pe_number = IODA_INVALID_PE;
166 INIT_LIST_HEAD(&pdn->child_list);
167 INIT_LIST_HEAD(&pdn->list);
168 list_add_tail(&pdn->list, &parent->child_list);
173 struct pci_dn *add_sriov_vf_pdns(struct pci_dev *pdev)
175 struct pci_dn *parent, *pdn;
178 /* Only support IOV for now */
179 if (WARN_ON(!pdev->is_physfn))
182 /* Check if VFs have been populated */
183 pdn = pci_get_pdn(pdev);
184 if (!pdn || (pdn->flags & PCI_DN_FLAG_IOV_VF))
187 pdn->flags |= PCI_DN_FLAG_IOV_VF;
188 parent = pci_bus_to_pdn(pdev->bus);
192 for (i = 0; i < pci_sriov_get_totalvfs(pdev); i++) {
193 struct eeh_dev *edev __maybe_unused;
195 pdn = add_one_sriov_vf_pdn(parent,
196 pci_iov_virtfn_bus(pdev, i),
197 pci_iov_virtfn_devfn(pdev, i));
199 dev_warn(&pdev->dev, "%s: Cannot create firmware data for VF#%d\n",
205 /* Create the EEH device for the VF */
206 edev = eeh_dev_init(pdn);
209 /* FIXME: these should probably be populated by the EEH probe */
212 #endif /* CONFIG_EEH */
214 return pci_get_pdn(pdev);
217 void remove_sriov_vf_pdns(struct pci_dev *pdev)
219 struct pci_dn *parent;
220 struct pci_dn *pdn, *tmp;
223 /* Only support IOV PF for now */
224 if (WARN_ON(!pdev->is_physfn))
227 /* Check if VFs have been populated */
228 pdn = pci_get_pdn(pdev);
229 if (!pdn || !(pdn->flags & PCI_DN_FLAG_IOV_VF))
232 pdn->flags &= ~PCI_DN_FLAG_IOV_VF;
233 parent = pci_bus_to_pdn(pdev->bus);
238 * We might introduce flag to pci_dn in future
239 * so that we can release VF's firmware data in
242 for (i = 0; i < pci_sriov_get_totalvfs(pdev); i++) {
243 struct eeh_dev *edev __maybe_unused;
245 list_for_each_entry_safe(pdn, tmp,
246 &parent->child_list, list) {
247 if (pdn->busno != pci_iov_virtfn_bus(pdev, i) ||
248 pdn->devfn != pci_iov_virtfn_devfn(pdev, i))
253 * Release EEH state for this VF. The PCI core
254 * has already torn down the pci_dev for this VF, but
255 * we're responsible to removing the eeh_dev since it
256 * has the same lifetime as the pci_dn that spawned it.
258 edev = pdn_to_eeh_dev(pdn);
261 * We allocate pci_dn's for the totalvfs count,
262 * but only only the vfs that were activated
263 * have a configured PE.
266 eeh_pe_tree_remove(edev);
271 #endif /* CONFIG_EEH */
273 if (!list_empty(&pdn->list))
274 list_del(&pdn->list);
280 #endif /* CONFIG_PCI_IOV */
282 struct pci_dn *pci_add_device_node_info(struct pci_controller *hose,
283 struct device_node *dn)
285 const __be32 *type = of_get_property(dn, "ibm,pci-config-space-type", NULL);
287 struct device_node *parent;
290 struct eeh_dev *edev;
293 pdn = kzalloc(sizeof(*pdn), GFP_KERNEL);
298 pdn->pe_number = IODA_INVALID_PE;
299 regs = of_get_property(dn, "reg", NULL);
301 u32 addr = of_read_number(regs, 1);
303 /* First register entry is addr (00BBSS00) */
304 pdn->busno = (addr >> 16) & 0xff;
305 pdn->devfn = (addr >> 8) & 0xff;
308 /* vendor/device IDs and class code */
309 regs = of_get_property(dn, "vendor-id", NULL);
310 pdn->vendor_id = regs ? of_read_number(regs, 1) : 0;
311 regs = of_get_property(dn, "device-id", NULL);
312 pdn->device_id = regs ? of_read_number(regs, 1) : 0;
313 regs = of_get_property(dn, "class-code", NULL);
314 pdn->class_code = regs ? of_read_number(regs, 1) : 0;
316 /* Extended config space */
317 pdn->pci_ext_config_space = (type && of_read_number(type, 1) == 1);
319 /* Create EEH device */
321 edev = eeh_dev_init(pdn);
328 /* Attach to parent node */
329 INIT_LIST_HEAD(&pdn->child_list);
330 INIT_LIST_HEAD(&pdn->list);
331 parent = of_get_parent(dn);
332 pdn->parent = parent ? PCI_DN(parent) : NULL;
335 list_add_tail(&pdn->list, &pdn->parent->child_list);
339 EXPORT_SYMBOL_GPL(pci_add_device_node_info);
341 void pci_remove_device_node_info(struct device_node *dn)
343 struct pci_dn *pdn = dn ? PCI_DN(dn) : NULL;
344 struct device_node *parent;
345 struct pci_dev *pdev;
347 struct eeh_dev *edev = pdn_to_eeh_dev(pdn);
356 WARN_ON(!list_empty(&pdn->child_list));
357 list_del(&pdn->list);
359 /* Drop the parent pci_dn's ref to our backing dt node */
360 parent = of_get_parent(dn);
365 * At this point we *might* still have a pci_dev that was
366 * instantiated from this pci_dn. So defer free()ing it until
367 * the pci_dev's release function is called.
369 pdev = pci_get_domain_bus_and_slot(pdn->phb->global_number,
370 pdn->busno, pdn->devfn);
372 /* NB: pdev has a ref to dn */
373 pci_dbg(pdev, "marked pdn (from %pOF) as dead\n", dn);
374 pdn->flags |= PCI_DN_FLAG_DEAD;
382 EXPORT_SYMBOL_GPL(pci_remove_device_node_info);
385 * Traverse a device tree stopping each PCI device in the tree.
386 * This is done depth first. As each node is processed, a "pre"
387 * function is called and the children are processed recursively.
389 * The "pre" func returns a value. If non-zero is returned from
390 * the "pre" func, the traversal stops and this value is returned.
391 * This return value is useful when using traverse as a method of
394 * NOTE: we do not run the func for devices that do not appear to
395 * be PCI except for the start node which we assume (this is good
396 * because the start node is often a phb which may be missing PCI
398 * We use the class-code as an indicator. If we run into
399 * one of these nodes we also assume its siblings are non-pci for
402 void *pci_traverse_device_nodes(struct device_node *start,
403 void *(*fn)(struct device_node *, void *),
406 struct device_node *dn, *nextdn;
409 /* We started with a phb, iterate all childs */
410 for (dn = start->child; dn; dn = nextdn) {
411 const __be32 *classp;
415 classp = of_get_property(dn, "class-code", NULL);
417 class = of_read_number(classp, 1);
425 /* If we are a PCI bridge, go down */
426 if (dn->child && ((class >> 8) == PCI_CLASS_BRIDGE_PCI ||
427 (class >> 8) == PCI_CLASS_BRIDGE_CARDBUS))
428 /* Depth first...do children */
430 else if (dn->sibling)
431 /* ok, try next sibling instead. */
432 nextdn = dn->sibling;
434 /* Walk up to next valid sibling. */
439 } while (dn->sibling == NULL);
440 nextdn = dn->sibling;
445 EXPORT_SYMBOL_GPL(pci_traverse_device_nodes);
447 static struct pci_dn *pci_dn_next_one(struct pci_dn *root,
450 struct list_head *next = pdn->child_list.next;
452 if (next != &pdn->child_list)
453 return list_entry(next, struct pci_dn, list);
459 next = pdn->list.next;
460 if (next != &pdn->parent->child_list)
466 return list_entry(next, struct pci_dn, list);
469 void *traverse_pci_dn(struct pci_dn *root,
470 void *(*fn)(struct pci_dn *, void *),
473 struct pci_dn *pdn = root;
476 /* Only scan the child nodes */
477 for (pdn = pci_dn_next_one(root, pdn); pdn;
478 pdn = pci_dn_next_one(root, pdn)) {
487 static void *add_pdn(struct device_node *dn, void *data)
489 struct pci_controller *hose = data;
492 pdn = pci_add_device_node_info(hose, dn);
494 return ERR_PTR(-ENOMEM);
500 * pci_devs_phb_init_dynamic - setup pci devices under this PHB
501 * phb: pci-to-host bridge (top-level bridge connecting to cpu)
503 * This routine is called both during boot, (before the memory
504 * subsystem is set up, before kmalloc is valid) and during the
505 * dynamic lpar operation of adding a PHB to a running system.
507 void pci_devs_phb_init_dynamic(struct pci_controller *phb)
509 struct device_node *dn = phb->dn;
512 /* PHB nodes themselves must not match */
513 pdn = pci_add_device_node_info(phb, dn);
515 pdn->devfn = pdn->busno = -1;
516 pdn->vendor_id = pdn->device_id = pdn->class_code = 0;
521 /* Update dn->phb ptrs for new phb and children devices */
522 pci_traverse_device_nodes(dn, add_pdn, phb);
526 * pci_devs_phb_init - Initialize phbs and pci devs under them.
528 * This routine walks over all phb's (pci-host bridges) on the
529 * system, and sets up assorted pci-related structures
530 * (including pci info in the device node structs) for each
531 * pci device found underneath. This routine runs once,
532 * early in the boot sequence.
534 static int __init pci_devs_phb_init(void)
536 struct pci_controller *phb, *tmp;
538 /* This must be done first so the device nodes have valid pci info! */
539 list_for_each_entry_safe(phb, tmp, &hose_list, list_node)
540 pci_devs_phb_init_dynamic(phb);
545 core_initcall(pci_devs_phb_init);
547 static void pci_dev_pdn_setup(struct pci_dev *pdev)
551 if (pdev->dev.archdata.pci_data)
554 /* Setup the fast path */
555 pdn = pci_get_pdn(pdev);
556 pdev->dev.archdata.pci_data = pdn;
558 DECLARE_PCI_FIXUP_EARLY(PCI_ANY_ID, PCI_ANY_ID, pci_dev_pdn_setup);