From 8344b568f5bdc7ee1bba909de3294c6348c36056 Mon Sep 17 00:00:00 2001 From: Alex Chiang Date: Tue, 10 Jun 2008 15:30:42 -0600 Subject: PCI: ACPI PCI slot detection driver Detect all physical PCI slots as described by ACPI, and create entries in /sys/bus/pci/slots/. Not all physical slots are hotpluggable, and the acpiphp module does not detect them. Now we know the physical PCI geography of our system, without caring about hotplug. [kaneshige.kenji@jp.fujitsu.com: export-kobject_rename-for-pci_hotplug_core] Signed-off-by: Kenji Kaneshige Acked-by: Greg KH [akpm@linux-foundation.org: build fix] [akpm@linux-foundation.org: fix build with CONFIG_DMI=n] Signed-off-by: Alex Chiang Cc: Greg KH Cc: Kristen Carlson Accardi Cc: Len Brown Acked-by: Len Brown Acked-by: Kenji Kaneshige Signed-off-by: Andrew Morton Signed-off-by: Andrew Morton Signed-off-by: Jesse Barnes --- drivers/acpi/pci_slot.c | 368 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 368 insertions(+) create mode 100644 drivers/acpi/pci_slot.c (limited to 'drivers/acpi/pci_slot.c') diff --git a/drivers/acpi/pci_slot.c b/drivers/acpi/pci_slot.c new file mode 100644 index 000000000000..b9ab030a52d5 --- /dev/null +++ b/drivers/acpi/pci_slot.c @@ -0,0 +1,368 @@ +/* + * pci_slot.c - ACPI PCI Slot Driver + * + * The code here is heavily leveraged from the acpiphp module. + * Thanks to Matthew Wilcox for much guidance. + * Thanks to Kenji Kaneshige for code + * review and fixes. + * + * Copyright (C) 2007 Alex Chiang + * Copyright (C) 2007 Hewlett-Packard Development Company, L.P. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * 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., + * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +static int debug; +static int check_sta_before_sun; + +#define DRIVER_VERSION "0.1" +#define DRIVER_AUTHOR "Alex Chiang " +#define DRIVER_DESC "ACPI PCI Slot Detection Driver" +MODULE_AUTHOR(DRIVER_AUTHOR); +MODULE_DESCRIPTION(DRIVER_DESC); +MODULE_LICENSE("GPL"); +MODULE_PARM_DESC(debug, "Debugging mode enabled or not"); +module_param(debug, bool, 0644); + +#define _COMPONENT ACPI_PCI_COMPONENT +ACPI_MODULE_NAME("pci_slot"); + +#define MY_NAME "pci_slot" +#define err(format, arg...) printk(KERN_ERR "%s: " format , MY_NAME , ## arg) +#define info(format, arg...) printk(KERN_INFO "%s: " format , MY_NAME , ## arg) +#define dbg(format, arg...) \ + do { \ + if (debug) \ + printk(KERN_DEBUG "%s: " format, \ + MY_NAME , ## arg); \ + } while (0) + +#define SLOT_NAME_SIZE 20 /* Inspired by #define in acpiphp.h */ + +struct acpi_pci_slot { + acpi_handle root_handle; /* handle of the root bridge */ + struct pci_slot *pci_slot; /* corresponding pci_slot */ + struct list_head list; /* node in the list of slots */ +}; + +static int acpi_pci_slot_add(acpi_handle handle); +static void acpi_pci_slot_remove(acpi_handle handle); + +static LIST_HEAD(slot_list); +static DEFINE_MUTEX(slot_list_lock); +static struct acpi_pci_driver acpi_pci_slot_driver = { + .add = acpi_pci_slot_add, + .remove = acpi_pci_slot_remove, +}; + +static int +check_slot(acpi_handle handle, int *device, unsigned long *sun) +{ + int retval = 0; + unsigned long adr, sta; + acpi_status status; + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; + + acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer); + dbg("Checking slot on path: %s\n", (char *)buffer.pointer); + + if (check_sta_before_sun) { + /* If SxFy doesn't have _STA, we just assume it's there */ + status = acpi_evaluate_integer(handle, "_STA", NULL, &sta); + if (ACPI_SUCCESS(status) && !(sta & ACPI_STA_DEVICE_PRESENT)) { + retval = -1; + goto out; + } + } + + status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr); + if (ACPI_FAILURE(status)) { + dbg("_ADR returned %d on %s\n", status, (char *)buffer.pointer); + retval = -1; + goto out; + } + + *device = (adr >> 16) & 0xffff; + + /* No _SUN == not a slot == bail */ + status = acpi_evaluate_integer(handle, "_SUN", NULL, sun); + if (ACPI_FAILURE(status)) { + dbg("_SUN returned %d on %s\n", status, (char *)buffer.pointer); + retval = -1; + goto out; + } + +out: + kfree(buffer.pointer); + return retval; +} + +struct callback_args { + acpi_walk_callback user_function; /* only for walk_p2p_bridge */ + struct pci_bus *pci_bus; + acpi_handle root_handle; +}; + +/* + * register_slot + * + * Called once for each SxFy object in the namespace. Don't worry about + * calling pci_create_slot multiple times for the same pci_bus:device, + * since each subsequent call simply bumps the refcount on the pci_slot. + * + * The number of calls to pci_destroy_slot from unregister_slot is + * symmetrical. + */ +static acpi_status +register_slot(acpi_handle handle, u32 lvl, void *context, void **rv) +{ + int device; + unsigned long sun; + char name[SLOT_NAME_SIZE]; + struct acpi_pci_slot *slot; + struct pci_slot *pci_slot; + struct callback_args *parent_context = context; + struct pci_bus *pci_bus = parent_context->pci_bus; + + if (check_slot(handle, &device, &sun)) + return AE_OK; + + slot = kmalloc(sizeof(*slot), GFP_KERNEL); + if (!slot) { + err("%s: cannot allocate memory\n", __func__); + return AE_OK; + } + + snprintf(name, sizeof(name), "%u", (u32)sun); + pci_slot = pci_create_slot(pci_bus, device, name); + if (IS_ERR(pci_slot)) { + err("pci_create_slot returned %ld\n", PTR_ERR(pci_slot)); + kfree(slot); + } + + slot->root_handle = parent_context->root_handle; + slot->pci_slot = pci_slot; + INIT_LIST_HEAD(&slot->list); + mutex_lock(&slot_list_lock); + list_add(&slot->list, &slot_list); + mutex_unlock(&slot_list_lock); + + dbg("pci_slot: %p, pci_bus: %x, device: %d, name: %s\n", + pci_slot, pci_bus->number, device, name); + + return AE_OK; +} + +/* + * walk_p2p_bridge - discover and walk p2p bridges + * @handle: points to an acpi_pci_root + * @context: p2p_bridge_context pointer + * + * Note that when we call ourselves recursively, we pass a different + * value of pci_bus in the child_context. + */ +static acpi_status +walk_p2p_bridge(acpi_handle handle, u32 lvl, void *context, void **rv) +{ + int device, function; + unsigned long adr; + acpi_status status; + acpi_handle dummy_handle; + acpi_walk_callback user_function; + + struct pci_dev *dev; + struct pci_bus *pci_bus; + struct callback_args child_context; + struct callback_args *parent_context = context; + + pci_bus = parent_context->pci_bus; + user_function = parent_context->user_function; + + status = acpi_get_handle(handle, "_ADR", &dummy_handle); + if (ACPI_FAILURE(status)) + return AE_OK; + + status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr); + if (ACPI_FAILURE(status)) + return AE_OK; + + device = (adr >> 16) & 0xffff; + function = adr & 0xffff; + + dev = pci_get_slot(pci_bus, PCI_DEVFN(device, function)); + if (!dev || !dev->subordinate) + goto out; + + child_context.pci_bus = dev->subordinate; + child_context.user_function = user_function; + child_context.root_handle = parent_context->root_handle; + + dbg("p2p bridge walk, pci_bus = %x\n", dev->subordinate->number); + status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1, + user_function, &child_context, NULL); + if (ACPI_FAILURE(status)) + goto out; + + status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1, + walk_p2p_bridge, &child_context, NULL); +out: + pci_dev_put(dev); + return AE_OK; +} + +/* + * walk_root_bridge - generic root bridge walker + * @handle: points to an acpi_pci_root + * @user_function: user callback for slot objects + * + * Call user_function for all objects underneath this root bridge. + * Walk p2p bridges underneath us and call user_function on those too. + */ +static int +walk_root_bridge(acpi_handle handle, acpi_walk_callback user_function) +{ + int seg, bus; + unsigned long tmp; + acpi_status status; + acpi_handle dummy_handle; + struct pci_bus *pci_bus; + struct callback_args context; + + /* If the bridge doesn't have _STA, we assume it is always there */ + status = acpi_get_handle(handle, "_STA", &dummy_handle); + if (ACPI_SUCCESS(status)) { + status = acpi_evaluate_integer(handle, "_STA", NULL, &tmp); + if (ACPI_FAILURE(status)) { + info("%s: _STA evaluation failure\n", __func__); + return 0; + } + if ((tmp & ACPI_STA_DEVICE_FUNCTIONING) == 0) + /* don't register this object */ + return 0; + } + + status = acpi_evaluate_integer(handle, "_SEG", NULL, &tmp); + seg = ACPI_SUCCESS(status) ? tmp : 0; + + status = acpi_evaluate_integer(handle, "_BBN", NULL, &tmp); + bus = ACPI_SUCCESS(status) ? tmp : 0; + + pci_bus = pci_find_bus(seg, bus); + if (!pci_bus) + return 0; + + context.pci_bus = pci_bus; + context.user_function = user_function; + context.root_handle = handle; + + dbg("root bridge walk, pci_bus = %x\n", pci_bus->number); + status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1, + user_function, &context, NULL); + if (ACPI_FAILURE(status)) + return status; + + status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1, + walk_p2p_bridge, &context, NULL); + if (ACPI_FAILURE(status)) + err("%s: walk_p2p_bridge failure - %d\n", __func__, status); + + return status; +} + +/* + * acpi_pci_slot_add + * @handle: points to an acpi_pci_root + */ +static int +acpi_pci_slot_add(acpi_handle handle) +{ + acpi_status status; + + status = walk_root_bridge(handle, register_slot); + if (ACPI_FAILURE(status)) + err("%s: register_slot failure - %d\n", __func__, status); + + return status; +} + +/* + * acpi_pci_slot_remove + * @handle: points to an acpi_pci_root + */ +static void +acpi_pci_slot_remove(acpi_handle handle) +{ + struct acpi_pci_slot *slot, *tmp; + + mutex_lock(&slot_list_lock); + list_for_each_entry_safe(slot, tmp, &slot_list, list) { + if (slot->root_handle == handle) { + list_del(&slot->list); + pci_destroy_slot(slot->pci_slot); + kfree(slot); + } + } + mutex_unlock(&slot_list_lock); +} + +static int do_sta_before_sun(const struct dmi_system_id *d) +{ + info("%s detected: will evaluate _STA before calling _SUN\n", d->ident); + check_sta_before_sun = 1; + return 0; +} + +static struct dmi_system_id acpi_pci_slot_dmi_table[] __initdata = { + /* + * Fujitsu Primequest machines will return 1023 to indicate an + * error if the _SUN method is evaluated on SxFy objects that + * are not present (as indicated by _STA), so for those machines, + * we want to check _STA before evaluating _SUN. + */ + { + .callback = do_sta_before_sun, + .ident = "Fujitsu PRIMEQUEST", + .matches = { + DMI_MATCH(DMI_BIOS_VENDOR, "FUJITSU LIMITED"), + DMI_MATCH(DMI_BIOS_VERSION, "PRIMEQUEST"), + }, + }, + {} +}; + +static int __init +acpi_pci_slot_init(void) +{ + dmi_check_system(acpi_pci_slot_dmi_table); + acpi_pci_register_driver(&acpi_pci_slot_driver); + return 0; +} + +static void __exit +acpi_pci_slot_exit(void) +{ + acpi_pci_unregister_driver(&acpi_pci_slot_driver); +} + +module_init(acpi_pci_slot_init); +module_exit(acpi_pci_slot_exit); -- cgit v1.2.3