39af9c325f3532e37013d53a6fbf0412bc482d63
[linux-2.6.git] / drivers / pci / hotplug / acpi_pcihp.c
1 /*
2  * Common ACPI functions for hot plug platforms
3  *
4  * Copyright (C) 2006 Intel Corporation
5  *
6  * All rights reserved.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or (at
11  * your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
16  * NON INFRINGEMENT.  See the GNU General Public License for more
17  * details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22  *
23  * Send feedback to <kristen.c.accardi@intel.com>
24  *
25  */
26
27 #include <linux/module.h>
28 #include <linux/kernel.h>
29 #include <linux/types.h>
30 #include <linux/pci.h>
31 #include <acpi/acpi.h>
32 #include <acpi/acpi_bus.h>
33 #include <acpi/actypes.h>
34 #include "pci_hotplug.h"
35
36 #define METHOD_NAME__SUN        "_SUN"
37 #define METHOD_NAME__HPP        "_HPP"
38 #define METHOD_NAME_OSHP        "OSHP"
39
40
41 static acpi_status
42 acpi_run_hpp(acpi_handle handle, struct hotplug_params *hpp)
43 {
44         acpi_status             status;
45         u8                      nui[4];
46         struct acpi_buffer      ret_buf = { 0, NULL};
47         struct acpi_buffer      string = { ACPI_ALLOCATE_BUFFER, NULL };
48         union acpi_object       *ext_obj, *package;
49         int                     i, len = 0;
50
51         acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);
52
53         /* get _hpp */
54         status = acpi_evaluate_object(handle, METHOD_NAME__HPP, NULL, &ret_buf);
55         switch (status) {
56         case AE_BUFFER_OVERFLOW:
57                 ret_buf.pointer = kmalloc (ret_buf.length, GFP_KERNEL);
58                 if (!ret_buf.pointer) {
59                         printk(KERN_ERR "%s:%s alloc for _HPP fail\n",
60                                 __FUNCTION__, (char *)string.pointer);
61                         acpi_os_free(string.pointer);
62                         return AE_NO_MEMORY;
63                 }
64                 status = acpi_evaluate_object(handle, METHOD_NAME__HPP,
65                                 NULL, &ret_buf);
66                 if (ACPI_SUCCESS(status))
67                         break;
68         default:
69                 if (ACPI_FAILURE(status)) {
70                         pr_debug("%s:%s _HPP fail=0x%x\n", __FUNCTION__,
71                                 (char *)string.pointer, status);
72                         acpi_os_free(string.pointer);
73                         return status;
74                 }
75         }
76
77         ext_obj = (union acpi_object *) ret_buf.pointer;
78         if (ext_obj->type != ACPI_TYPE_PACKAGE) {
79                 printk(KERN_ERR "%s:%s _HPP obj not a package\n", __FUNCTION__,
80                                 (char *)string.pointer);
81                 status = AE_ERROR;
82                 goto free_and_return;
83         }
84
85         len = ext_obj->package.count;
86         package = (union acpi_object *) ret_buf.pointer;
87         for ( i = 0; (i < len) || (i < 4); i++) {
88                 ext_obj = (union acpi_object *) &package->package.elements[i];
89                 switch (ext_obj->type) {
90                 case ACPI_TYPE_INTEGER:
91                         nui[i] = (u8)ext_obj->integer.value;
92                         break;
93                 default:
94                         printk(KERN_ERR "%s:%s _HPP obj type incorrect\n",
95                                 __FUNCTION__, (char *)string.pointer);
96                         status = AE_ERROR;
97                         goto free_and_return;
98                 }
99         }
100
101         hpp->cache_line_size = nui[0];
102         hpp->latency_timer = nui[1];
103         hpp->enable_serr = nui[2];
104         hpp->enable_perr = nui[3];
105
106         pr_debug("  _HPP: cache_line_size=0x%x\n", hpp->cache_line_size);
107         pr_debug("  _HPP: latency timer  =0x%x\n", hpp->latency_timer);
108         pr_debug("  _HPP: enable SERR    =0x%x\n", hpp->enable_serr);
109         pr_debug("  _HPP: enable PERR    =0x%x\n", hpp->enable_perr);
110
111 free_and_return:
112         acpi_os_free(string.pointer);
113         acpi_os_free(ret_buf.pointer);
114         return status;
115 }
116
117
118
119 /* acpi_run_oshp - get control of hotplug from the firmware
120  *
121  * @handle - the handle of the hotplug controller.
122  */
123 acpi_status acpi_run_oshp(acpi_handle handle)
124 {
125         acpi_status             status;
126         struct acpi_buffer      string = { ACPI_ALLOCATE_BUFFER, NULL };
127
128         acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);
129
130         /* run OSHP */
131         status = acpi_evaluate_object(handle, METHOD_NAME_OSHP, NULL, NULL);
132         if (ACPI_FAILURE(status))
133                 printk(KERN_ERR "%s:%s OSHP fails=0x%x\n", __FUNCTION__,
134                         (char *)string.pointer, status);
135         else
136                 pr_debug("%s:%s OSHP passes\n", __FUNCTION__,
137                         (char *)string.pointer);
138
139         acpi_os_free(string.pointer);
140         return status;
141 }
142 EXPORT_SYMBOL_GPL(acpi_run_oshp);
143
144
145
146 /* acpi_get_hp_params_from_firmware
147  *
148  * @dev - the pci_dev of the newly added device
149  * @hpp - allocated by the caller
150  */
151 acpi_status acpi_get_hp_params_from_firmware(struct pci_dev *dev,
152                 struct hotplug_params *hpp)
153 {
154         acpi_status status = AE_NOT_FOUND;
155         struct pci_dev *pdev = dev;
156
157         /*
158          * _HPP settings apply to all child buses, until another _HPP is
159          * encountered. If we don't find an _HPP for the input pci dev,
160          * look for it in the parent device scope since that would apply to
161          * this pci dev. If we don't find any _HPP, use hardcoded defaults
162          */
163         while (pdev && (ACPI_FAILURE(status))) {
164                 acpi_handle handle = DEVICE_ACPI_HANDLE(&(pdev->dev));
165                 if (!handle)
166                         break;
167                 status = acpi_run_hpp(handle, hpp);
168                 if (!(pdev->bus->parent))
169                         break;
170                 /* Check if a parent object supports _HPP */
171                 pdev = pdev->bus->parent->self;
172         }
173         return status;
174 }
175 EXPORT_SYMBOL_GPL(acpi_get_hp_params_from_firmware);
176
177
178 /* acpi_root_bridge - check to see if this acpi object is a root bridge
179  *
180  * @handle - the acpi object in question.
181  */
182 int acpi_root_bridge(acpi_handle handle)
183 {
184         acpi_status status;
185         struct acpi_device_info *info;
186         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
187         int i;
188
189         status = acpi_get_object_info(handle, &buffer);
190         if (ACPI_SUCCESS(status)) {
191                 info = buffer.pointer;
192                 if ((info->valid & ACPI_VALID_HID) &&
193                         !strcmp(PCI_ROOT_HID_STRING,
194                                         info->hardware_id.value)) {
195                         acpi_os_free(buffer.pointer);
196                         return 1;
197                 }
198                 if (info->valid & ACPI_VALID_CID) {
199                         for (i=0; i < info->compatibility_id.count; i++) {
200                                 if (!strcmp(PCI_ROOT_HID_STRING,
201                                         info->compatibility_id.id[i].value)) {
202                                         acpi_os_free(buffer.pointer);
203                                         return 1;
204                                 }
205                         }
206                 }
207                 acpi_os_free(buffer.pointer);
208         }
209         return 0;
210 }
211 EXPORT_SYMBOL_GPL(acpi_root_bridge);