PageRenderTime 37ms CodeModel.GetById 12ms app.highlight 18ms RepoModel.GetById 2ms app.codeStats 0ms

/drivers/acpi/hardware/hwacpi.c

https://bitbucket.org/evzijst/gittest
C | 230 lines | 85 code | 44 blank | 101 comment | 14 complexity | d426a77ba390ee2a4af60cd17c95db2d MD5 | raw file
  1
  2/******************************************************************************
  3 *
  4 * Module Name: hwacpi - ACPI Hardware Initialization/Mode Interface
  5 *
  6 *****************************************************************************/
  7
  8/*
  9 * Copyright (C) 2000 - 2005, R. Byron Moore
 10 * All rights reserved.
 11 *
 12 * Redistribution and use in source and binary forms, with or without
 13 * modification, are permitted provided that the following conditions
 14 * are met:
 15 * 1. Redistributions of source code must retain the above copyright
 16 *    notice, this list of conditions, and the following disclaimer,
 17 *    without modification.
 18 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 19 *    substantially similar to the "NO WARRANTY" disclaimer below
 20 *    ("Disclaimer") and any redistribution must be conditioned upon
 21 *    including a substantially similar Disclaimer requirement for further
 22 *    binary redistribution.
 23 * 3. Neither the names of the above-listed copyright holders nor the names
 24 *    of any contributors may be used to endorse or promote products derived
 25 *    from this software without specific prior written permission.
 26 *
 27 * Alternatively, this software may be distributed under the terms of the
 28 * GNU General Public License ("GPL") version 2 as published by the Free
 29 * Software Foundation.
 30 *
 31 * NO WARRANTY
 32 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 33 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 34 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 35 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 36 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 37 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 38 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 40 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 41 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 42 * POSSIBILITY OF SUCH DAMAGES.
 43 */
 44
 45
 46#include <acpi/acpi.h>
 47
 48
 49#define _COMPONENT          ACPI_HARDWARE
 50	 ACPI_MODULE_NAME    ("hwacpi")
 51
 52
 53/******************************************************************************
 54 *
 55 * FUNCTION:    acpi_hw_initialize
 56 *
 57 * PARAMETERS:  None
 58 *
 59 * RETURN:      Status
 60 *
 61 * DESCRIPTION: Initialize and validate various ACPI registers
 62 *
 63 ******************************************************************************/
 64
 65acpi_status
 66acpi_hw_initialize (
 67	void)
 68{
 69	acpi_status                     status;
 70
 71
 72	ACPI_FUNCTION_TRACE ("hw_initialize");
 73
 74
 75	/* We must have the ACPI tables by the time we get here */
 76
 77	if (!acpi_gbl_FADT) {
 78		ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "A FADT is not loaded\n"));
 79
 80		return_ACPI_STATUS (AE_NO_ACPI_TABLES);
 81	}
 82
 83	/* Sanity check the FADT for valid values */
 84
 85	status = acpi_ut_validate_fadt ();
 86	if (ACPI_FAILURE (status)) {
 87		return_ACPI_STATUS (status);
 88	}
 89
 90	return_ACPI_STATUS (AE_OK);
 91}
 92
 93
 94/******************************************************************************
 95 *
 96 * FUNCTION:    acpi_hw_set_mode
 97 *
 98 * PARAMETERS:  Mode            - SYS_MODE_ACPI or SYS_MODE_LEGACY
 99 *
100 * RETURN:      Status
101 *
102 * DESCRIPTION: Transitions the system into the requested mode.
103 *
104 ******************************************************************************/
105
106acpi_status
107acpi_hw_set_mode (
108	u32                             mode)
109{
110
111	acpi_status                     status;
112	u32                             retry;
113
114
115	ACPI_FUNCTION_TRACE ("hw_set_mode");
116
117	/*
118	 * ACPI 2.0 clarified that if SMI_CMD in FADT is zero,
119	 * system does not support mode transition.
120	 */
121	if (!acpi_gbl_FADT->smi_cmd) {
122		ACPI_REPORT_ERROR (("No SMI_CMD in FADT, mode transition failed.\n"));
123		return_ACPI_STATUS (AE_NO_HARDWARE_RESPONSE);
124	}
125
126	/*
127	 * ACPI 2.0 clarified the meaning of ACPI_ENABLE and ACPI_DISABLE
128	 * in FADT: If it is zero, enabling or disabling is not supported.
129	 * As old systems may have used zero for mode transition,
130	 * we make sure both the numbers are zero to determine these
131	 * transitions are not supported.
132	 */
133	if (!acpi_gbl_FADT->acpi_enable && !acpi_gbl_FADT->acpi_disable) {
134		ACPI_REPORT_ERROR (("No ACPI mode transition supported in this system (enable/disable both zero)\n"));
135		return_ACPI_STATUS (AE_OK);
136	}
137
138	switch (mode) {
139	case ACPI_SYS_MODE_ACPI:
140
141		/* BIOS should have disabled ALL fixed and GP events */
142
143		status = acpi_os_write_port (acpi_gbl_FADT->smi_cmd,
144				  (u32) acpi_gbl_FADT->acpi_enable, 8);
145		ACPI_DEBUG_PRINT ((ACPI_DB_INFO, "Attempting to enable ACPI mode\n"));
146		break;
147
148	case ACPI_SYS_MODE_LEGACY:
149
150		/*
151		 * BIOS should clear all fixed status bits and restore fixed event
152		 * enable bits to default
153		 */
154		status = acpi_os_write_port (acpi_gbl_FADT->smi_cmd,
155				 (u32) acpi_gbl_FADT->acpi_disable, 8);
156		ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
157				 "Attempting to enable Legacy (non-ACPI) mode\n"));
158		break;
159
160	default:
161		return_ACPI_STATUS (AE_BAD_PARAMETER);
162	}
163
164	if (ACPI_FAILURE (status)) {
165		ACPI_REPORT_ERROR (("Could not write mode change, %s\n", acpi_format_exception (status)));
166		return_ACPI_STATUS (status);
167	}
168
169	/*
170	 * Some hardware takes a LONG time to switch modes. Give them 3 sec to
171	 * do so, but allow faster systems to proceed more quickly.
172	 */
173	retry = 3000;
174	while (retry) {
175		if (acpi_hw_get_mode() == mode) {
176			ACPI_DEBUG_PRINT ((ACPI_DB_INFO, "Mode %X successfully enabled\n", mode));
177			return_ACPI_STATUS (AE_OK);
178		}
179		acpi_os_stall(1000);
180		retry--;
181	}
182
183	ACPI_REPORT_ERROR (("Hardware never changed modes\n"));
184	return_ACPI_STATUS (AE_NO_HARDWARE_RESPONSE);
185}
186
187
188/******************************************************************************
189 *
190 * FUNCTION:    acpi_hw_get_mode
191 *
192 * PARAMETERS:  none
193 *
194 * RETURN:      SYS_MODE_ACPI or SYS_MODE_LEGACY
195 *
196 * DESCRIPTION: Return current operating state of system.  Determined by
197 *              querying the SCI_EN bit.
198 *
199 ******************************************************************************/
200
201u32
202acpi_hw_get_mode (void)
203{
204	acpi_status                     status;
205	u32                             value;
206
207
208	ACPI_FUNCTION_TRACE ("hw_get_mode");
209
210
211	/*
212	 * ACPI 2.0 clarified that if SMI_CMD in FADT is zero,
213	 * system does not support mode transition.
214	 */
215	if (!acpi_gbl_FADT->smi_cmd) {
216		return_VALUE (ACPI_SYS_MODE_ACPI);
217	}
218
219	status = acpi_get_register (ACPI_BITREG_SCI_ENABLE, &value, ACPI_MTX_LOCK);
220	if (ACPI_FAILURE (status)) {
221		return_VALUE (ACPI_SYS_MODE_LEGACY);
222	}
223
224	if (value) {
225		return_VALUE (ACPI_SYS_MODE_ACPI);
226	}
227	else {
228		return_VALUE (ACPI_SYS_MODE_LEGACY);
229	}
230}