drivers/acpi/ioapic.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * IOAPIC/IOxAPIC/IOSAPIC driver
   4  *
   5  * Copyright (C) 2009 Fujitsu Limited.
   6  * (c) Copyright 2009 Hewlett-Packard Development Company, L.P.
   7  *
   8  * Copyright (C) 2014 Intel Corporation
   9  *
  10  * Based on original drivers/pci/ioapic.c
  11  *      Yinghai Lu <yinghai@kernel.org>
  12  *      Jiang Liu <jiang.liu@intel.com>
  13  */
  14
  15 /*
  16  * This driver manages I/O APICs added by hotplug after boot.
  17  * We try to claim all I/O APIC devices, but those present at boot were
  18  * registered when we parsed the ACPI MADT.
  19  */
  20
  21 #define pr_fmt(fmt) "ACPI: IOAPIC: " fmt
  22
  23 #include <linux/slab.h>
  24 #include <linux/acpi.h>
  25 #include <linux/pci.h>
  26 #include <acpi/acpi.h>
  27
  28 struct acpi_pci_ioapic {
  29         acpi_handle     root_handle;
  30         acpi_handle     handle;
  31         u32             gsi_base;
  32         struct resource res;
  33         struct pci_dev  *pdev;
  34         struct list_head list;
  35 };
  36
  37 static LIST_HEAD(ioapic_list);
  38 static DEFINE_MUTEX(ioapic_list_lock);
  39
  40 static acpi_status setup_res(struct acpi_resource *acpi_res, void *data)
  41 {
  42         struct resource *res = data;
  43         struct resource_win win;
  44
  45         /*
  46          * We might assign this to 'res' later, make sure all pointers are
  47          * cleared before the resource is added to the global list
  48          */
  49         memset(&win, 0, sizeof(win));
  50
  51         res->flags = 0;
  52         if (acpi_dev_filter_resource_type(acpi_res, IORESOURCE_MEM))
  53                 return AE_OK;
  54
  55         if (!acpi_dev_resource_memory(acpi_res, res)) {
  56                 if (acpi_dev_resource_address_space(acpi_res, &win) ||
  57                     acpi_dev_resource_ext_address_space(acpi_res, &win))
  58                         *res = win.res;
  59         }
  60         if ((res->flags & IORESOURCE_PREFETCH) ||
  61             (res->flags & IORESOURCE_DISABLED))
  62                 res->flags = 0;
  63
  64         return AE_CTRL_TERMINATE;
  65 }
  66
  67 static bool acpi_is_ioapic(acpi_handle handle, char **type)
  68 {
  69         acpi_status status;
  70         struct acpi_device_info *info;
  71         char *hid = NULL;
  72         bool match = false;
  73
  74         if (!acpi_has_method(handle, "_GSB"))
  75                 return false;
  76
  77         status = acpi_get_object_info(handle, &info);
  78         if (ACPI_SUCCESS(status)) {
  79                 if (info->valid & ACPI_VALID_HID)
  80                         hid = info->hardware_id.string;
  81                 if (hid) {
  82                         if (strcmp(hid, "ACPI0009") == 0) {
  83                                 *type = "IOxAPIC";
  84                                 match = true;
  85                         } else if (strcmp(hid, "ACPI000A") == 0) {
  86                                 *type = "IOAPIC";
  87                                 match = true;
  88                         }
  89                 }
  90                 kfree(info);
  91         }
  92
  93         return match;
  94 }
  95
  96 static acpi_status handle_ioapic_add(acpi_handle handle, u32 lvl,
  97                                      void *context, void **rv)
  98 {
  99         acpi_status status;
 100         unsigned long long gsi_base;
 101         struct acpi_pci_ioapic *ioapic;
 102         struct pci_dev *dev = NULL;
 103         struct resource *res = NULL, *pci_res = NULL, *crs_res;
 104         char *type = NULL;
 105
 106         if (!acpi_is_ioapic(handle, &type))
 107                 return AE_OK;
 108
 109         mutex_lock(&ioapic_list_lock);
 110         list_for_each_entry(ioapic, &ioapic_list, list)
 111                 if (ioapic->handle == handle) {
 112                         mutex_unlock(&ioapic_list_lock);
 113                         return AE_OK;
 114                 }
 115
 116         status = acpi_evaluate_integer(handle, "_GSB", NULL, &gsi_base);
 117         if (ACPI_FAILURE(status)) {
 118                 acpi_handle_warn(handle, "failed to evaluate _GSB method\n");
 119                 goto exit;
 120         }
 121
 122         ioapic = kzalloc(sizeof(*ioapic), GFP_KERNEL);
 123         if (!ioapic) {
 124                 pr_err("cannot allocate memory for new IOAPIC\n");
 125                 goto exit;
 126         } else {
 127                 ioapic->root_handle = (acpi_handle)context;
 128                 ioapic->handle = handle;
 129                 ioapic->gsi_base = (u32)gsi_base;
 130                 INIT_LIST_HEAD(&ioapic->list);
 131         }
 132
 133         if (acpi_ioapic_registered(handle, (u32)gsi_base))
 134                 goto done;
 135
 136         dev = acpi_get_pci_dev(handle);
 137         if (dev && pci_resource_len(dev, 0)) {
 138                 if (pci_enable_device(dev) < 0)
 139                         goto exit_put;
 140                 pci_set_master(dev);
 141                 if (pci_request_region(dev, 0, type))
 142                         goto exit_disable;
 143                 pci_res = &dev->resource[0];
 144                 ioapic->pdev = dev;
 145         } else {
 146                 pci_dev_put(dev);
 147                 dev = NULL;
 148         }
 149
 150         crs_res = &ioapic->res;
 151         acpi_walk_resources(handle, METHOD_NAME__CRS, setup_res, crs_res);
 152         crs_res->name = type;
 153         crs_res->flags |= IORESOURCE_BUSY;
 154         if (crs_res->flags == 0) {
 155                 acpi_handle_warn(handle, "failed to get resource\n");
 156                 goto exit_release;
 157         } else if (insert_resource(&iomem_resource, crs_res)) {
 158                 acpi_handle_warn(handle, "failed to insert resource\n");
 159                 goto exit_release;
 160         }
 161
 162         /* try pci resource first, then "_CRS" resource */
 163         res = pci_res;
 164         if (!res || !res->flags)
 165                 res = crs_res;
 166
 167         if (acpi_register_ioapic(handle, res->start, (u32)gsi_base)) {
 168                 acpi_handle_warn(handle, "failed to register IOAPIC\n");
 169                 goto exit_release;
 170         }
 171 done:
 172         list_add(&ioapic->list, &ioapic_list);
 173         mutex_unlock(&ioapic_list_lock);
 174
 175         if (dev)
 176                 dev_info(&dev->dev, "%s at %pR, GSI %u\n",
 177                          type, res, (u32)gsi_base);
 178         else
 179                 acpi_handle_info(handle, "%s at %pR, GSI %u\n",
 180                                  type, res, (u32)gsi_base);
 181
 182         return AE_OK;
 183
 184 exit_release:
 185         if (dev)
 186                 pci_release_region(dev, 0);
 187         if (ioapic->res.flags && ioapic->res.parent)
 188                 release_resource(&ioapic->res);
 189 exit_disable:
 190         if (dev)
 191                 pci_disable_device(dev);
 192 exit_put:
 193         pci_dev_put(dev);
 194         kfree(ioapic);
 195 exit:
 196         mutex_unlock(&ioapic_list_lock);
 197         *(acpi_status *)rv = AE_ERROR;
 198         return AE_OK;
 199 }
 200
 201 int acpi_ioapic_add(acpi_handle root_handle)
 202 {
 203         acpi_status status, retval = AE_OK;
 204
 205         status = acpi_walk_namespace(ACPI_TYPE_DEVICE, root_handle,
 206                                      UINT_MAX, handle_ioapic_add, NULL,
 207                                      root_handle, (void **)&retval);
 208
 209         return ACPI_SUCCESS(status) && ACPI_SUCCESS(retval) ? 0 : -ENODEV;
 210 }
 211
 212 void pci_ioapic_remove(struct acpi_pci_root *root)
 213 {
 214         struct acpi_pci_ioapic *ioapic, *tmp;
 215
 216         mutex_lock(&ioapic_list_lock);
 217         list_for_each_entry_safe(ioapic, tmp, &ioapic_list, list) {
 218                 if (root->device->handle != ioapic->root_handle)
 219                         continue;
 220                 if (ioapic->pdev) {
 221                         pci_release_region(ioapic->pdev, 0);
 222                         pci_disable_device(ioapic->pdev);
 223                         pci_dev_put(ioapic->pdev);
 224                 }
 225         }
 226         mutex_unlock(&ioapic_list_lock);
 227 }
 228
 229 int acpi_ioapic_remove(struct acpi_pci_root *root)
 230 {
 231         int retval = 0;
 232         struct acpi_pci_ioapic *ioapic, *tmp;
 233
 234         mutex_lock(&ioapic_list_lock);
 235         list_for_each_entry_safe(ioapic, tmp, &ioapic_list, list) {
 236                 if (root->device->handle != ioapic->root_handle)
 237                         continue;
 238                 if (acpi_unregister_ioapic(ioapic->handle, ioapic->gsi_base))
 239                         retval = -EBUSY;
 240                 if (ioapic->res.flags && ioapic->res.parent)
 241                         release_resource(&ioapic->res);
 242                 list_del(&ioapic->list);
 243                 kfree(ioapic);
 244         }
 245         mutex_unlock(&ioapic_list_lock);
 246
 247         return retval;
 248 }