1 /******************************************************************************
2 *
3 * Module Name: hwacpi - ACPI Hardware Initialization/Mode Interface
4 *
5 *****************************************************************************/
6
7 /*
8 * Copyright (C) 2000 - 2016, Intel Corp.
9 * All rights reserved.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions, and the following disclaimer,
16 * without modification.
17 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18 * substantially similar to the "NO WARRANTY" disclaimer below
19 * ("Disclaimer") and any redistribution must be conditioned upon
20 * including a substantially similar Disclaimer requirement for further
21 * binary redistribution.
22 * 3. Neither the names of the above-listed copyright holders nor the names
23 * of any contributors may be used to endorse or promote products derived
24 * from this software without specific prior written permission.
25 *
26 * Alternatively, this software may be distributed under the terms of the
27 * GNU General Public License ("GPL") version 2 as published by the Free
28 * Software Foundation.
29 *
30 * NO WARRANTY
31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41 * POSSIBILITY OF SUCH DAMAGES.
42 */
43
44 #include "acpi.h"
45 #include "accommon.h"
46
47
48 #define _COMPONENT ACPI_HARDWARE
49 ACPI_MODULE_NAME ("hwacpi")
50
51
52 #if (!ACPI_REDUCED_HARDWARE) /* Entire module */
53 /******************************************************************************
54 *
55 * FUNCTION: AcpiHwSetMode
56 *
57 * PARAMETERS: Mode - SYS_MODE_ACPI or SYS_MODE_LEGACY
58 *
59 * RETURN: Status
60 *
61 * DESCRIPTION: Transitions the system into the requested mode.
62 *
63 ******************************************************************************/
64
65 ACPI_STATUS
AcpiHwSetMode(UINT32 Mode)66 AcpiHwSetMode (
67 UINT32 Mode)
68 {
69
70 ACPI_STATUS Status;
71 UINT32 Retry;
72
73
74 ACPI_FUNCTION_TRACE (HwSetMode);
75
76
77 /* If the Hardware Reduced flag is set, machine is always in acpi mode */
78
79 if (AcpiGbl_ReducedHardware)
80 {
81 return_ACPI_STATUS (AE_OK);
82 }
83
84 /*
85 * ACPI 2.0 clarified that if SMI_CMD in FADT is zero,
86 * system does not support mode transition.
87 */
88 if (!AcpiGbl_FADT.SmiCommand)
89 {
90 ACPI_ERROR ((AE_INFO, "No SMI_CMD in FADT, mode transition failed"));
91 return_ACPI_STATUS (AE_NO_HARDWARE_RESPONSE);
92 }
93
94 /*
95 * ACPI 2.0 clarified the meaning of ACPI_ENABLE and ACPI_DISABLE
96 * in FADT: If it is zero, enabling or disabling is not supported.
97 * As old systems may have used zero for mode transition,
98 * we make sure both the numbers are zero to determine these
99 * transitions are not supported.
100 */
101 if (!AcpiGbl_FADT.AcpiEnable && !AcpiGbl_FADT.AcpiDisable)
102 {
103 ACPI_ERROR ((AE_INFO,
104 "No ACPI mode transition supported in this system "
105 "(enable/disable both zero)"));
106 return_ACPI_STATUS (AE_OK);
107 }
108
109 switch (Mode)
110 {
111 case ACPI_SYS_MODE_ACPI:
112
113 /* BIOS should have disabled ALL fixed and GP events */
114
115 Status = AcpiHwWritePort (AcpiGbl_FADT.SmiCommand,
116 (UINT32) AcpiGbl_FADT.AcpiEnable, 8);
117 ACPI_DEBUG_PRINT ((ACPI_DB_INFO, "Attempting to enable ACPI mode\n"));
118 break;
119
120 case ACPI_SYS_MODE_LEGACY:
121 /*
122 * BIOS should clear all fixed status bits and restore fixed event
123 * enable bits to default
124 */
125 Status = AcpiHwWritePort (AcpiGbl_FADT.SmiCommand,
126 (UINT32) AcpiGbl_FADT.AcpiDisable, 8);
127 ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
128 "Attempting to enable Legacy (non-ACPI) mode\n"));
129 break;
130
131 default:
132
133 return_ACPI_STATUS (AE_BAD_PARAMETER);
134 }
135
136 if (ACPI_FAILURE (Status))
137 {
138 ACPI_EXCEPTION ((AE_INFO, Status,
139 "Could not write ACPI mode change"));
140 return_ACPI_STATUS (Status);
141 }
142
143 /*
144 * Some hardware takes a LONG time to switch modes. Give them 3 sec to
145 * do so, but allow faster systems to proceed more quickly.
146 */
147 Retry = 3000;
148 while (Retry)
149 {
150 if (AcpiHwGetMode () == Mode)
151 {
152 ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
153 "Mode %X successfully enabled\n", Mode));
154 return_ACPI_STATUS (AE_OK);
155 }
156 AcpiOsStall (ACPI_USEC_PER_MSEC);
157 Retry--;
158 }
159
160 ACPI_ERROR ((AE_INFO, "Hardware did not change modes"));
161 return_ACPI_STATUS (AE_NO_HARDWARE_RESPONSE);
162 }
163
164
165 /*******************************************************************************
166 *
167 * FUNCTION: AcpiHwGetMode
168 *
169 * PARAMETERS: none
170 *
171 * RETURN: SYS_MODE_ACPI or SYS_MODE_LEGACY
172 *
173 * DESCRIPTION: Return current operating state of system. Determined by
174 * querying the SCI_EN bit.
175 *
176 ******************************************************************************/
177
178 UINT32
AcpiHwGetMode(void)179 AcpiHwGetMode (
180 void)
181 {
182 ACPI_STATUS Status;
183 UINT32 Value;
184
185
186 ACPI_FUNCTION_TRACE (HwGetMode);
187
188
189 /* If the Hardware Reduced flag is set, machine is always in acpi mode */
190
191 if (AcpiGbl_ReducedHardware)
192 {
193 return_UINT32 (ACPI_SYS_MODE_ACPI);
194 }
195
196 /*
197 * ACPI 2.0 clarified that if SMI_CMD in FADT is zero,
198 * system does not support mode transition.
199 */
200 if (!AcpiGbl_FADT.SmiCommand)
201 {
202 return_UINT32 (ACPI_SYS_MODE_ACPI);
203 }
204
205 Status = AcpiReadBitRegister (ACPI_BITREG_SCI_ENABLE, &Value);
206 if (ACPI_FAILURE (Status))
207 {
208 return_UINT32 (ACPI_SYS_MODE_LEGACY);
209 }
210
211 if (Value)
212 {
213 return_UINT32 (ACPI_SYS_MODE_ACPI);
214 }
215 else
216 {
217 return_UINT32 (ACPI_SYS_MODE_LEGACY);
218 }
219 }
220
221 #endif /* !ACPI_REDUCED_HARDWARE */
222