1 /* 2 * pci_slot.c - ACPI PCI Slot Driver 3 * 4 * The code here is heavily leveraged from the acpiphp module. 5 * Thanks to Matthew Wilcox <matthew@wil.cx> for much guidance. 6 * Thanks to Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> for code 7 * review and fixes. 8 * 9 * Copyright (C) 2007-2008 Hewlett-Packard Development Company, L.P. 10 * Alex Chiang <achiang@hp.com> 11 * 12 * Copyright (C) 2013 Huawei Tech. Co., Ltd. 13 * Jiang Liu <jiang.liu@huawei.com> 14 * 15 * This program is free software; you can redistribute it and/or modify it 16 * under the terms and conditions of the GNU General Public License, 17 * version 2, as published by the Free Software Foundation. 18 * 19 * This program is distributed in the hope that it will be useful, but 20 * WITHOUT ANY WARRANTY; without even the implied warranty of 21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 22 * General Public License for more details. 23 */ 24 25 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 26 27 #include <linux/kernel.h> 28 #include <linux/init.h> 29 #include <linux/slab.h> 30 #include <linux/types.h> 31 #include <linux/list.h> 32 #include <linux/pci.h> 33 #include <linux/acpi.h> 34 #include <linux/dmi.h> 35 #include <linux/pci-acpi.h> 36 37 static int check_sta_before_sun; 38 39 #define _COMPONENT ACPI_PCI_COMPONENT 40 ACPI_MODULE_NAME("pci_slot"); 41 42 #define SLOT_NAME_SIZE 21 /* Inspired by #define in acpiphp.h */ 43 44 struct acpi_pci_slot { 45 struct pci_slot *pci_slot; /* corresponding pci_slot */ 46 struct list_head list; /* node in the list of slots */ 47 }; 48 49 static LIST_HEAD(slot_list); 50 static DEFINE_MUTEX(slot_list_lock); 51 52 static int 53 check_slot(acpi_handle handle, unsigned long long *sun) 54 { 55 int device = -1; 56 unsigned long long adr, sta; 57 acpi_status status; 58 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 59 60 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer); 61 pr_debug("Checking slot on path: %s\n", (char *)buffer.pointer); 62 63 if (check_sta_before_sun) { 64 /* If SxFy doesn't have _STA, we just assume it's there */ 65 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta); 66 if (ACPI_SUCCESS(status) && !(sta & ACPI_STA_DEVICE_PRESENT)) 67 goto out; 68 } 69 70 status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr); 71 if (ACPI_FAILURE(status)) { 72 pr_debug("_ADR returned %d on %s\n", 73 status, (char *)buffer.pointer); 74 goto out; 75 } 76 77 /* No _SUN == not a slot == bail */ 78 status = acpi_evaluate_integer(handle, "_SUN", NULL, sun); 79 if (ACPI_FAILURE(status)) { 80 pr_debug("_SUN returned %d on %s\n", 81 status, (char *)buffer.pointer); 82 goto out; 83 } 84 85 device = (adr >> 16) & 0xffff; 86 out: 87 kfree(buffer.pointer); 88 return device; 89 } 90 91 /* 92 * Check whether handle has an associated slot and create PCI slot if it has. 93 */ 94 static acpi_status 95 register_slot(acpi_handle handle, u32 lvl, void *context, void **rv) 96 { 97 int device; 98 unsigned long long sun; 99 char name[SLOT_NAME_SIZE]; 100 struct acpi_pci_slot *slot; 101 struct pci_slot *pci_slot; 102 struct pci_bus *pci_bus = context; 103 104 device = check_slot(handle, &sun); 105 if (device < 0) 106 return AE_OK; 107 108 /* 109 * There may be multiple PCI functions associated with the same slot. 110 * Check whether PCI slot has already been created for this PCI device. 111 */ 112 list_for_each_entry(slot, &slot_list, list) { 113 pci_slot = slot->pci_slot; 114 if (pci_slot->bus == pci_bus && pci_slot->number == device) 115 return AE_OK; 116 } 117 118 slot = kmalloc(sizeof(*slot), GFP_KERNEL); 119 if (!slot) 120 return AE_OK; 121 122 snprintf(name, sizeof(name), "%llu", sun); 123 pci_slot = pci_create_slot(pci_bus, device, name, NULL); 124 if (IS_ERR(pci_slot)) { 125 pr_err("pci_create_slot returned %ld\n", PTR_ERR(pci_slot)); 126 kfree(slot); 127 return AE_OK; 128 } 129 130 slot->pci_slot = pci_slot; 131 list_add(&slot->list, &slot_list); 132 133 get_device(&pci_bus->dev); 134 135 pr_debug("%p, pci_bus: %x, device: %d, name: %s\n", 136 pci_slot, pci_bus->number, device, name); 137 138 return AE_OK; 139 } 140 141 void acpi_pci_slot_enumerate(struct pci_bus *bus) 142 { 143 acpi_handle handle = ACPI_HANDLE(bus->bridge); 144 145 if (handle) { 146 mutex_lock(&slot_list_lock); 147 acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1, 148 register_slot, NULL, bus, NULL); 149 mutex_unlock(&slot_list_lock); 150 } 151 } 152 153 void acpi_pci_slot_remove(struct pci_bus *bus) 154 { 155 struct acpi_pci_slot *slot, *tmp; 156 157 mutex_lock(&slot_list_lock); 158 list_for_each_entry_safe(slot, tmp, &slot_list, list) { 159 if (slot->pci_slot->bus == bus) { 160 list_del(&slot->list); 161 pci_destroy_slot(slot->pci_slot); 162 put_device(&bus->dev); 163 kfree(slot); 164 } 165 } 166 mutex_unlock(&slot_list_lock); 167 } 168 169 static int do_sta_before_sun(const struct dmi_system_id *d) 170 { 171 pr_info("%s detected: will evaluate _STA before calling _SUN\n", 172 d->ident); 173 check_sta_before_sun = 1; 174 return 0; 175 } 176 177 static struct dmi_system_id acpi_pci_slot_dmi_table[] __initdata = { 178 /* 179 * Fujitsu Primequest machines will return 1023 to indicate an 180 * error if the _SUN method is evaluated on SxFy objects that 181 * are not present (as indicated by _STA), so for those machines, 182 * we want to check _STA before evaluating _SUN. 183 */ 184 { 185 .callback = do_sta_before_sun, 186 .ident = "Fujitsu PRIMEQUEST", 187 .matches = { 188 DMI_MATCH(DMI_BIOS_VENDOR, "FUJITSU LIMITED"), 189 DMI_MATCH(DMI_BIOS_VERSION, "PRIMEQUEST"), 190 }, 191 }, 192 {} 193 }; 194 195 void __init acpi_pci_slot_init(void) 196 { 197 dmi_check_system(acpi_pci_slot_dmi_table); 198 } 199