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Diffstat (limited to 'arch/ppc64/kernel/pci_dn.c')
| -rw-r--r-- | arch/ppc64/kernel/pci_dn.c | 198 |
1 files changed, 198 insertions, 0 deletions
diff --git a/arch/ppc64/kernel/pci_dn.c b/arch/ppc64/kernel/pci_dn.c new file mode 100644 index 000000000000..ec345462afc3 --- /dev/null +++ b/arch/ppc64/kernel/pci_dn.c @@ -0,0 +1,198 @@ +/* + * pci_dn.c + * + * Copyright (C) 2001 Todd Inglett, IBM Corporation + * + * PCI manipulation via device_nodes. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ +#include <linux/kernel.h> +#include <linux/pci.h> +#include <linux/string.h> +#include <linux/init.h> + +#include <asm/io.h> +#include <asm/prom.h> +#include <asm/pci-bridge.h> +#include <asm/pSeries_reconfig.h> + +#include "pci.h" + +/* + * Traverse_func that inits the PCI fields of the device node. + * NOTE: this *must* be done before read/write config to the device. + */ +static void * __devinit update_dn_pci_info(struct device_node *dn, void *data) +{ + struct pci_controller *phb = data; + int *type = (int *)get_property(dn, "ibm,pci-config-space-type", NULL); + u32 *regs; + + dn->phb = phb; + regs = (u32 *)get_property(dn, "reg", NULL); + if (regs) { + /* First register entry is addr (00BBSS00) */ + dn->busno = (regs[0] >> 16) & 0xff; + dn->devfn = (regs[0] >> 8) & 0xff; + } + + dn->pci_ext_config_space = (type && *type == 1); + return NULL; +} + +/* + * 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 *traverse_pci_devices(struct device_node *start, traverse_func pre, + void *data) +{ + struct device_node *dn, *nextdn; + void *ret; + + /* We started with a phb, iterate all childs */ + for (dn = start->child; dn; dn = nextdn) { + u32 *classp, class; + + nextdn = NULL; + classp = (u32 *)get_property(dn, "class-code", NULL); + class = classp ? *classp : 0; + + if (pre && ((ret = pre(dn, data)) != NULL)) + 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; +} + +void __devinit pci_devs_phb_init_dynamic(struct pci_controller *phb) +{ + struct device_node * dn = (struct device_node *) phb->arch_data; + + /* PHB nodes themselves must not match */ + dn->devfn = dn->busno = -1; + dn->phb = phb; + + /* Update dn->phb ptrs for new phb and children devices */ + traverse_pci_devices(dn, update_dn_pci_info, phb); +} + +/* + * Traversal func that looks for a <busno,devfcn> value. + * If found, the device_node is returned (thus terminating the traversal). + */ +static void *is_devfn_node(struct device_node *dn, void *data) +{ + int busno = ((unsigned long)data >> 8) & 0xff; + int devfn = ((unsigned long)data) & 0xff; + + return ((devfn == dn->devfn) && (busno == dn->busno)) ? dn : NULL; +} + +/* + * This is the "slow" path for looking up a device_node from a + * pci_dev. It will hunt for the device under its parent's + * phb and then update sysdata for a future fastpath. + * + * It may also do fixups on the actual device since this happens + * on the first read/write. + * + * Note that it also must deal with devices that don't exist. + * In this case it may probe for real hardware ("just in case") + * and add a device_node to the device tree if necessary. + * + */ +struct device_node *fetch_dev_dn(struct pci_dev *dev) +{ + struct device_node *orig_dn = dev->sysdata; + struct pci_controller *phb = orig_dn->phb; /* assume same phb as orig_dn */ + struct device_node *phb_dn; + struct device_node *dn; + unsigned long searchval = (dev->bus->number << 8) | dev->devfn; + + phb_dn = phb->arch_data; + dn = traverse_pci_devices(phb_dn, is_devfn_node, (void *)searchval); + if (dn) + dev->sysdata = dn; + return dn; +} +EXPORT_SYMBOL(fetch_dev_dn); + +static int pci_dn_reconfig_notifier(struct notifier_block *nb, unsigned long action, void *node) +{ + struct device_node *np = node; + int err = NOTIFY_OK; + + switch (action) { + case PSERIES_RECONFIG_ADD: + update_dn_pci_info(np, np->parent->phb); + break; + default: + err = NOTIFY_DONE; + break; + } + return err; +} + +static struct notifier_block pci_dn_reconfig_nb = { + .notifier_call = pci_dn_reconfig_notifier, +}; + +/* + * Actually initialize the phbs. + * The buswalk on this phb has not happened yet. + */ +void __init pci_devs_phb_init(void) +{ + struct pci_controller *phb, *tmp; + + /* This must be done first so the device nodes have valid pci info! */ + list_for_each_entry_safe(phb, tmp, &hose_list, list_node) + pci_devs_phb_init_dynamic(phb); + + pSeries_reconfig_notifier_register(&pci_dn_reconfig_nb); +} |