// SPDX-License-Identifier: GPL-2.0-or-later
/*
* pci_dn.c
*
* Copyright (C) 2001 Todd Inglett, IBM Corporation
*
* PCI manipulation via device_nodes.
*/
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/string.h>
#include <linux/export.h>
#include <linux/init.h>
#include <linux/gfp.h>
#include <linux/of.h>
#include <asm/io.h>
#include <asm/pci-bridge.h>
#include <asm/ppc-pci.h>
#include <asm/firmware.h>
#include <asm/eeh.h>
/*
* The function is used to find the firmware data of one
* specific PCI device, which is attached to the indicated
* PCI bus. For VFs, their firmware data is linked to that
* one of PF's bridge. For other devices, their firmware
* data is linked to that of their bridge.
*/
static struct pci_dn *pci_bus_to_pdn(struct pci_bus *bus)
{
struct pci_bus *pbus;
struct device_node *dn;
struct pci_dn *pdn;
/*
* We probably have virtual bus which doesn't
* have associated bridge.
*/
pbus = bus;
while (pbus) {
if (pci_is_root_bus(pbus) || pbus->self)
break;
pbus = pbus->parent;
}
/*
* Except virtual bus, all PCI buses should
* have device nodes.
*/
dn = pci_bus_to_OF_node(pbus);
pdn = dn ? PCI_DN(dn) : NULL;
return pdn;
}
struct pci_dn *pci_get_pdn_by_devfn(struct pci_bus *bus,
int devfn)
{
struct device_node *dn = NULL;
struct pci_dn *parent, *pdn;
struct pci_dev *pdev = NULL;
/* Fast path: fetch from PCI device */
list_for_each_entry(pdev, &bus->devices, bus_list) {
if (pdev->devfn == devfn) {
if (pdev->dev.archdata.pci_data)
return pdev->dev.archdata.pci_data;
dn = pci_device_to_OF_node(pdev);
break;
}
}
/* Fast path: fetch from device node */
pdn = dn ? PCI_DN(dn) : NULL;
if (pdn)
return pdn;
/* Slow path: fetch from firmware data hierarchy */
parent = pci_bus_to_pdn(bus);
if (!parent)
return NULL;
list_for_each_entry(pdn, &parent->child_list, list) {
if (pdn->busno == bus->number &&
pdn->devfn == devfn)
return pdn;
}
return NULL;
}
struct pci_dn *pci_get_pdn(struct pci_dev *pdev)
{
struct device_node *dn;
struct pci_dn *parent, *pdn;
/* Search device directly */
if (pdev->dev.archdata.pci_data)
return pdev->dev.archdata.pci_data;
/* Check device node */
dn = pci_device_to_OF_node(pdev);
pdn = dn ? PCI_DN(dn) : NULL;
if (pdn)
return pdn;
/*
* VFs don't have device nodes. We hook their
* firmware data to PF's bridge.
*/
parent = pci_bus_to_pdn(pdev->bus);
if (!parent)
return NULL;
list_for_each_entry(pdn, &parent->child_list, list) {
if (pdn->busno == pdev->bus->number &&
pdn->devfn == pdev->devfn)
return pdn;
}
return NULL;
}
#ifdef CONFIG_EEH
static struct eeh_dev *eeh_dev_init(struct pci_dn *pdn)
{
struct eeh_dev *edev;
/* Allocate EEH device */
edev = kzalloc(sizeof(*edev), GFP_KERNEL);
if (!edev)
return NULL;
/* Associate EEH device with OF node */
pdn->edev = edev;
edev->pdn = pdn;
edev->bdfn = (pdn->busno << 8) | pdn->devfn;
edev->controller = pdn->phb;
return edev;
}
#endif /* CONFIG_EEH */
#ifdef CONFIG_PCI_IOV
static struct pci_dn *add_one_sriov_vf_pdn(struct pci_dn *parent,
int busno, int devfn)
{
struct pci_dn *pdn;
/* Except PHB, we always have the parent */
if (!parent)
return NULL;
pdn = kzalloc(sizeof(*pdn), GFP_KERNEL);
if (!pdn)
return NULL;
pdn->phb = parent->phb;
pdn->parent = parent;
pdn->busno = busno;
pdn->devfn = devfn;
pdn->pe_number = IODA_INVALID_PE;
INIT_LIST_HEAD(&pdn->child_list);
INIT_LIST_HEAD(&pdn->list);
list_add_tail(&pdn->list, &parent->child_list);
return pdn;
}
struct pci_dn *add_sriov_vf_pdns(struct pci_dev *pdev)
{
struct pci_dn *parent, *pdn;
int i;
/* Only support IOV for now */
if (WARN_ON(!pdev->is_physfn))
return NULL;
/* Check if VFs have been populated */
pdn = pci_get_pdn(pdev);
if (!pdn || (pdn->flags & PCI_DN_FLAG_IOV_VF))
return NULL;
pdn->flags |= PCI_DN_FLAG_IOV_VF;
parent = pci_bus_to_pdn(pdev->bus);
if (!parent)
return NULL;
for (i = 0; i < pci_sriov_get_totalvfs(pdev); i++) {
struct eeh_dev *edev __maybe_unused;
pdn = add_one_sriov_vf_pdn(parent,
pci_iov_virtfn_bus(pdev, i),
pci_iov_virtfn_devfn(pdev, i));
if (!pdn) {
dev_warn(&pdev->dev, "%s: Cannot create firmware data for VF#%d\n",
__func__, i);
return NULL;
}
#ifdef CONFIG_EEH
/* Create the EEH device for the VF */
edev = eeh_dev_init(pdn);
BUG_ON(!edev);
/* FIXME: these should probably be populated by the EEH probe */
edev->physfn = pdev;
edev->vf_index = i;
#endif /* CONFIG_EEH */
}
return pci_get_pdn(pdev);
}
void remove_sriov_vf_pdns(struct pci_dev *pdev)
{
struct pci_dn *parent;
struct pci_dn *pdn, *tmp;
int i;
/* Only support IOV PF for now */
if (WARN_ON(!pdev->is_physfn))
return;
/* Check if VFs have been populated */
pdn = pci_get_pdn(pdev);
if (!pdn || !(pdn->flags & PCI_DN_FLAG_IOV_VF))
return;
pdn->flags &= ~PCI_DN_FLAG_IOV_VF;
parent = pci_bus_to_pdn(pdev->bus);
if (!parent)
return;
/*
* We might introduce flag to pci_dn in future
* so that we can release VF's firmware data in
* a batch mode.
*/
for (i = 0; i < pci_sriov_get_totalvfs(pdev); i++) {
struct eeh_dev *edev __maybe_unused;
list_for_each_entry_safe(pdn, tmp,
&parent->child_list, list) {
if (pdn->busno != pci_iov_virtfn_bus(pdev, i) ||
pdn->devfn != pci_iov_virtfn_devfn(pdev, i))
continue;
#ifdef CONFIG_EEH
/*
* Release EEH state for this VF. The PCI core
* has already torn down the pci_dev for this VF, but
* we're responsible to removing the eeh_dev since it
* has the same lifetime as the pci_dn that spawned it.
*/
edev = pdn_to_eeh_dev(pdn);
if (edev) {
/*
* We allocate pci_dn's for the totalvfs count,
* but only the vfs that were activated
* have a configured PE.
*/
if (edev->pe)
eeh_pe_tree_remove(edev);
pdn->edev = NULL;
kfree(edev);
}
#endif /* CONFIG_EEH */
if (!list_empty(&pdn->list))
list_del(&pdn->list);
kfree(pdn);
}
}
}
#endif /* CONFIG_PCI_IOV */
struct pci_dn *pci_add_device_node_info(struct pci_controller *hose,
struct device_node *dn)
{
const __be32 *type = of_get_property(dn, "ibm,pci-config-space-type", NULL);
const __be32 *regs;
struct device_node *parent;
struct pci_dn *pdn;
#ifdef CONFIG_EEH
struct eeh_dev *edev;
#endif
pdn = kzalloc(sizeof(*pdn), GFP_KERNEL);
if (pdn == NULL)
return NULL;
dn->data = pdn;
pdn->phb = hose;
pdn->pe_number = IODA_INVALID_PE;
regs = of_get_property(dn, "reg", NULL);
if (regs) {
u32 addr = of_read_number(regs, 1);
/* First register entry is addr (00BBSS00) */
pdn->busno = (addr >> 16) & 0xff;
pdn->devfn = (addr >> 8) & 0xff;
}
/* vendor/device IDs and class code */
regs = of_get_property(dn, "vendor-id", NULL);
pdn->vendor_id = regs ? of_read_number(regs, 1) : 0;
regs = of_get_property(dn, "device-id", NULL);
pdn->device_id = regs ? of_read_number(regs, 1) : 0;
regs = of_get_property(dn, "class-code", NULL);
pdn->class_code = regs ? of_read_number(regs, 1) : 0;
/* Extended config space */
pdn->pci_ext_config_space = (type && of_read_number(type, 1) == 1);
/* Create EEH device */
#ifdef CONFIG_EEH
edev = eeh_dev_init(pdn);
if (!edev) {
kfree(pdn);
return NULL;
}
#endif
/* Attach to parent node */
INIT_LIST_HEAD(&pdn->child_list);
INIT_LIST_HEAD(&pdn->list);
parent = of_get_parent(dn);
pdn->parent = parent ? PCI_DN(parent) : NULL;
of_node_put(parent);
if (pdn->parent)
list_add_tail(&pdn->list, &pdn->parent->child_list);
return pdn;
}
EXPORT_SYMBOL_GPL(pci_add_device_node_info);
void pci_remove_device_node_info(struct device_node *dn)
{
struct pci_dn *pdn = dn ? PCI_DN(dn) : NULL;
struct device_node *parent;
struct pci_dev *pdev;
#ifdef CONFIG_EEH
struct eeh_dev *edev = pdn_to_eeh_dev(pdn);
if (edev)
edev->pdn = NULL;
#endif
if (!pdn)
return;
WARN_ON(!list_empty(&pdn->child_list));
list_del(&pdn->list);
/* Drop the parent pci_dn's ref to our backing dt node */
parent = of_get_parent(dn);
if (parent)
of_node_put(parent);
/*
* At this point we *might* still have a pci_dev that was
* instantiated from this pci_dn. So defer free()ing it until
* the pci_dev's release function is called.
*/
pdev = pci_get_domain_bus_and_slot(pdn->phb->global_number,
pdn->busno, pdn->devfn);
if (pdev) {
/* NB: pdev has a ref to dn */
pci_dbg(pdev, "marked pdn (from %pOF) as dead\n", dn);
pdn->flags |= PCI_DN_FLAG_DEAD;
} else {
dn->data = NULL;
kfree(pdn);
}
pci_dev_put(pdev);
}
EXPORT_SYMBOL_GPL(pci_remove_device_node_info);
/*
* Traverse a device tree stopping each PCI device in the tree.
* This is done depth first. As each node is processed, a "pre"
* function is called and the children are processed recursively.
*
* The "pre" func returns a value. If non-zero is returned from
* the "pre" func, the traversal stops and this value is returned.
* This return value is useful when using traverse as a method of
* finding a device.
*
* NOTE: we do not run the func for devices that do not appear to
* be PCI except for the start node which we assume (this is good
* because the start node is often a phb which may be missing PCI
* properties).
* We use the class-code as an indicator. If we run into
* one of these nodes we also assume its siblings are non-pci for
* performance.
*/
void *pci_traverse_device_nodes(struct device_node *start,
void *(*fn)(struct device_node *, void *),
void *data)
{
struct device_node *dn, *nextdn;
void *ret;
/* We started with a phb, iterate all childs */
for (dn = start->child; dn; dn = nextdn) {
const __be32 *classp;
u32 class = 0;
nextdn = NULL;
classp = of_get_property(dn, "class-code", NULL);
if (classp)
class = of_read_number(classp, 1);
if (fn) {
ret = fn(dn, data);
if (ret)
return ret;
}
/* If we are a PCI bridge, go down */
if (dn->child && ((class >> 8) == PCI_CLASS_BRIDGE_PCI ||
(class >> 8) == PCI_CLASS_BRIDGE_CARDBUS))
/* Depth first...do children */
nextdn = dn->child;
else if (dn->sibling)
/* ok, try next sibling instead. */
nextdn = dn->sibling;
if (!nextdn) {
/* Walk up to next valid sibling. */
do {
dn = dn->parent;
if (dn == start)
return NULL;
} while (dn->sibling == NULL);
nextdn = dn->sibling;
}
}
return NULL;
}
EXPORT_SYMBOL_GPL(pci_traverse_device_nodes);
static void *add_pdn(struct device_node *dn, void *data)
{
struct pci_controller *hose = data;
struct pci_dn *pdn;
pdn = pci_add_device_node_info(hose, dn);
if (!pdn)
return ERR_PTR(-ENOMEM);
return NULL;
}
/**
* pci_devs_phb_init_dynamic - setup pci devices under this PHB
* phb: pci-to-host bridge (top-level bridge connecting to cpu)
*
* This routine is called both during boot, (before the memory
* subsystem is set up, before kmalloc is valid) and during the
* dynamic lpar operation of adding a PHB to a running system.
*/
void pci_devs_phb_init_dynamic(struct pci_controller *phb)
{
struct device_node *dn = phb->dn;
struct pci_dn *pdn;
/* PHB nodes themselves must not match */
pdn = pci_add_device_node_info(phb, dn);
if (pdn) {
pdn->devfn = pdn->busno = -1;
pdn->vendor_id = pdn->device_id = pdn->class_code = 0;
pdn->phb = phb;
phb->pci_data = pdn;
}
/* Update dn->phb ptrs for new phb and children devices */
pci_traverse_device_nodes(dn, add_pdn, phb);
}
static void pci_dev_pdn_setup(struct pci_dev *pdev)
{
struct pci_dn *pdn;
if (pdev->dev.archdata.pci_data)
return;
/* Setup the fast path */
pdn = pci_get_pdn(pdev);
pdev->dev.archdata.pci_data = pdn;
}
DECLARE_PCI_FIXUP_EARLY(PCI_ANY_ID, PCI_ANY_ID, pci_dev_pdn_setup);
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