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