linux/drivers/acpi/ioapic.c
<<
>>
Prefs
   1/*
   2 * IOAPIC/IOxAPIC/IOSAPIC driver
   3 *
   4 * Copyright (C) 2009 Fujitsu Limited.
   5 * (c) Copyright 2009 Hewlett-Packard Development Company, L.P.
   6 *
   7 * Copyright (C) 2014 Intel Corporation
   8 *
   9 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License version 2 as
  11 * published by the Free Software Foundation.
  12 *
  13 * Based on original drivers/pci/ioapic.c
  14 *      Yinghai Lu <yinghai@kernel.org>
  15 *      Jiang Liu <jiang.liu@intel.com>
  16 */
  17
  18/*
  19 * This driver manages I/O APICs added by hotplug after boot.
  20 * We try to claim all I/O APIC devices, but those present at boot were
  21 * registered when we parsed the ACPI MADT.
  22 */
  23
  24#define pr_fmt(fmt) "ACPI : IOAPIC: " fmt
  25
  26#include <linux/slab.h>
  27#include <linux/acpi.h>
  28#include <linux/pci.h>
  29#include <acpi/acpi.h>
  30
  31struct acpi_pci_ioapic {
  32        acpi_handle     root_handle;
  33        acpi_handle     handle;
  34        u32             gsi_base;
  35        struct resource res;
  36        struct pci_dev  *pdev;
  37        struct list_head list;
  38};
  39
  40static LIST_HEAD(ioapic_list);
  41static DEFINE_MUTEX(ioapic_list_lock);
  42
  43static acpi_status setup_res(struct acpi_resource *acpi_res, void *data)
  44{
  45        struct resource *res = data;
  46        struct resource_win win;
  47
  48        /*
  49         * We might assign this to 'res' later, make sure all pointers are
  50         * cleared before the resource is added to the global list
  51         */
  52        memset(&win, 0, sizeof(win));
  53
  54        res->flags = 0;
  55        if (acpi_dev_filter_resource_type(acpi_res, IORESOURCE_MEM))
  56                return AE_OK;
  57
  58        if (!acpi_dev_resource_memory(acpi_res, res)) {
  59                if (acpi_dev_resource_address_space(acpi_res, &win) ||
  60                    acpi_dev_resource_ext_address_space(acpi_res, &win))
  61                        *res = win.res;
  62        }
  63        if ((res->flags & IORESOURCE_PREFETCH) ||
  64            (res->flags & IORESOURCE_DISABLED))
  65                res->flags = 0;
  66
  67        return AE_CTRL_TERMINATE;
  68}
  69
  70static bool acpi_is_ioapic(acpi_handle handle, char **type)
  71{
  72        acpi_status status;
  73        struct acpi_device_info *info;
  74        char *hid = NULL;
  75        bool match = false;
  76
  77        if (!acpi_has_method(handle, "_GSB"))
  78                return false;
  79
  80        status = acpi_get_object_info(handle, &info);
  81        if (ACPI_SUCCESS(status)) {
  82                if (info->valid & ACPI_VALID_HID)
  83                        hid = info->hardware_id.string;
  84                if (hid) {
  85                        if (strcmp(hid, "ACPI0009") == 0) {
  86                                *type = "IOxAPIC";
  87                                match = true;
  88                        } else if (strcmp(hid, "ACPI000A") == 0) {
  89                                *type = "IOAPIC";
  90                                match = true;
  91                        }
  92                }
  93                kfree(info);
  94        }
  95
  96        return match;
  97}
  98
  99static acpi_status handle_ioapic_add(acpi_handle handle, u32 lvl,
 100                                     void *context, void **rv)
 101{
 102        acpi_status status;
 103        unsigned long long gsi_base;
 104        struct acpi_pci_ioapic *ioapic;
 105        struct pci_dev *dev = NULL;
 106        struct resource *res = NULL, *pci_res = NULL, *crs_res;
 107        char *type = NULL;
 108
 109        if (!acpi_is_ioapic(handle, &type))
 110                return AE_OK;
 111
 112        mutex_lock(&ioapic_list_lock);
 113        list_for_each_entry(ioapic, &ioapic_list, list)
 114                if (ioapic->handle == handle) {
 115                        mutex_unlock(&ioapic_list_lock);
 116                        return AE_OK;
 117                }
 118
 119        status = acpi_evaluate_integer(handle, "_GSB", NULL, &gsi_base);
 120        if (ACPI_FAILURE(status)) {
 121                acpi_handle_warn(handle, "failed to evaluate _GSB method\n");
 122                goto exit;
 123        }
 124
 125        ioapic = kzalloc(sizeof(*ioapic), GFP_KERNEL);
 126        if (!ioapic) {
 127                pr_err("cannot allocate memory for new IOAPIC\n");
 128                goto exit;
 129        } else {
 130                ioapic->root_handle = (acpi_handle)context;
 131                ioapic->handle = handle;
 132                ioapic->gsi_base = (u32)gsi_base;
 133                INIT_LIST_HEAD(&ioapic->list);
 134        }
 135
 136        if (acpi_ioapic_registered(handle, (u32)gsi_base))
 137                goto done;
 138
 139        dev = acpi_get_pci_dev(handle);
 140        if (dev && pci_resource_len(dev, 0)) {
 141                if (pci_enable_device(dev) < 0)
 142                        goto exit_put;
 143                pci_set_master(dev);
 144                if (pci_request_region(dev, 0, type))
 145                        goto exit_disable;
 146                pci_res = &dev->resource[0];
 147                ioapic->pdev = dev;
 148        } else {
 149                pci_dev_put(dev);
 150                dev = NULL;
 151        }
 152
 153        crs_res = &ioapic->res;
 154        acpi_walk_resources(handle, METHOD_NAME__CRS, setup_res, crs_res);
 155        crs_res->name = type;
 156        crs_res->flags |= IORESOURCE_BUSY;
 157        if (crs_res->flags == 0) {
 158                acpi_handle_warn(handle, "failed to get resource\n");
 159                goto exit_release;
 160        } else if (insert_resource(&iomem_resource, crs_res)) {
 161                acpi_handle_warn(handle, "failed to insert resource\n");
 162                goto exit_release;
 163        }
 164
 165        /* try pci resource first, then "_CRS" resource */
 166        res = pci_res;
 167        if (!res || !res->flags)
 168                res = crs_res;
 169
 170        if (acpi_register_ioapic(handle, res->start, (u32)gsi_base)) {
 171                acpi_handle_warn(handle, "failed to register IOAPIC\n");
 172                goto exit_release;
 173        }
 174done:
 175        list_add(&ioapic->list, &ioapic_list);
 176        mutex_unlock(&ioapic_list_lock);
 177
 178        if (dev)
 179                dev_info(&dev->dev, "%s at %pR, GSI %u\n",
 180                         type, res, (u32)gsi_base);
 181        else
 182                acpi_handle_info(handle, "%s at %pR, GSI %u\n",
 183                                 type, res, (u32)gsi_base);
 184
 185        return AE_OK;
 186
 187exit_release:
 188        if (dev)
 189                pci_release_region(dev, 0);
 190        if (ioapic->res.flags && ioapic->res.parent)
 191                release_resource(&ioapic->res);
 192exit_disable:
 193        if (dev)
 194                pci_disable_device(dev);
 195exit_put:
 196        pci_dev_put(dev);
 197        kfree(ioapic);
 198exit:
 199        mutex_unlock(&ioapic_list_lock);
 200        *(acpi_status *)rv = AE_ERROR;
 201        return AE_OK;
 202}
 203
 204int acpi_ioapic_add(acpi_handle root_handle)
 205{
 206        acpi_status status, retval = AE_OK;
 207
 208        status = acpi_walk_namespace(ACPI_TYPE_DEVICE, root_handle,
 209                                     UINT_MAX, handle_ioapic_add, NULL,
 210                                     root_handle, (void **)&retval);
 211
 212        return ACPI_SUCCESS(status) && ACPI_SUCCESS(retval) ? 0 : -ENODEV;
 213}
 214
 215void pci_ioapic_remove(struct acpi_pci_root *root)
 216{
 217        struct acpi_pci_ioapic *ioapic, *tmp;
 218
 219        mutex_lock(&ioapic_list_lock);
 220        list_for_each_entry_safe(ioapic, tmp, &ioapic_list, list) {
 221                if (root->device->handle != ioapic->root_handle)
 222                        continue;
 223                if (ioapic->pdev) {
 224                        pci_release_region(ioapic->pdev, 0);
 225                        pci_disable_device(ioapic->pdev);
 226                        pci_dev_put(ioapic->pdev);
 227                }
 228        }
 229        mutex_unlock(&ioapic_list_lock);
 230}
 231
 232int acpi_ioapic_remove(struct acpi_pci_root *root)
 233{
 234        int retval = 0;
 235        struct acpi_pci_ioapic *ioapic, *tmp;
 236
 237        mutex_lock(&ioapic_list_lock);
 238        list_for_each_entry_safe(ioapic, tmp, &ioapic_list, list) {
 239                if (root->device->handle != ioapic->root_handle)
 240                        continue;
 241                if (acpi_unregister_ioapic(ioapic->handle, ioapic->gsi_base))
 242                        retval = -EBUSY;
 243                if (ioapic->res.flags && ioapic->res.parent)
 244                        release_resource(&ioapic->res);
 245                list_del(&ioapic->list);
 246                kfree(ioapic);
 247        }
 248        mutex_unlock(&ioapic_list_lock);
 249
 250        return retval;
 251}
 252