1 /*
2  * Copyright (C) 2016 Michael Brown <mbrown@fensystems.co.uk>.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License as
6  * published by the Free Software Foundation; either version 2 of the
7  * License, or any later version.
8  *
9  * This program is distributed in the hope that it will be useful, but
10  * WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12  * General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17  * 02110-1301, USA.
18  *
19  * You can also choose to distribute this program under the terms of
20  * the Unmodified Binary Distribution Licence (as given in the file
21  * COPYING.UBDL), provided that you have satisfied its requirements.
22  */
23 
24 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
25 
26 #include <unistd.h>
27 #include <errno.h>
28 #include <byteswap.h>
29 #include <ipxe/io.h>
30 #include <ipxe/acpi.h>
31 #include <ipxe/acpipwr.h>
32 
33 /** @file
34  *
35  * ACPI power off
36  *
37  */
38 
39 /** Colour for debug messages */
40 #define colour FADT_SIGNATURE
41 
42 /** _S5_ signature */
43 #define S5_SIGNATURE ACPI_SIGNATURE ( '_', 'S', '5', '_' )
44 
45 /**
46  * Power off the computer using ACPI
47  *
48  * @ret rc		Return status code
49  */
acpi_poweroff(void)50 int acpi_poweroff ( void ) {
51 	struct acpi_fadt fadtab;
52 	userptr_t fadt;
53 	unsigned int pm1a_cnt_blk;
54 	unsigned int pm1b_cnt_blk;
55 	unsigned int pm1a_cnt;
56 	unsigned int pm1b_cnt;
57 	unsigned int slp_typa;
58 	unsigned int slp_typb;
59 	int s5;
60 	int rc;
61 
62 	/* Locate FADT */
63 	fadt = acpi_find ( FADT_SIGNATURE, 0 );
64 	if ( ! fadt ) {
65 		DBGC ( colour, "ACPI could not find FADT\n" );
66 		return -ENOENT;
67 	}
68 
69 	/* Read FADT */
70 	copy_from_user ( &fadtab, fadt, 0, sizeof ( fadtab ) );
71 	pm1a_cnt_blk = le32_to_cpu ( fadtab.pm1a_cnt_blk );
72 	pm1b_cnt_blk = le32_to_cpu ( fadtab.pm1b_cnt_blk );
73 	pm1a_cnt = ( pm1a_cnt_blk + ACPI_PM1_CNT );
74 	pm1b_cnt = ( pm1b_cnt_blk + ACPI_PM1_CNT );
75 
76 	/* Extract \_S5 from DSDT or any SSDT */
77 	s5 = acpi_sx ( S5_SIGNATURE );
78 	if ( s5 < 0 ) {
79 		rc = s5;
80 		DBGC ( colour, "ACPI could not extract \\_S5: %s\n",
81 		       strerror ( rc ) );
82 		return rc;
83 	}
84 
85 	/* Power off system */
86 	if ( pm1a_cnt_blk ) {
87 		slp_typa = ( ( s5 >> 0 ) & 0xff );
88 		DBGC ( colour, "ACPI PM1a sleep type %#x => %04x\n",
89 		       slp_typa, pm1a_cnt );
90 		outw ( ( ACPI_PM1_CNT_SLP_TYP ( slp_typa ) |
91 			 ACPI_PM1_CNT_SLP_EN ), pm1a_cnt );
92 	}
93 	if ( pm1b_cnt_blk ) {
94 		slp_typb = ( ( s5 >> 8 ) & 0xff );
95 		DBGC ( colour, "ACPI PM1b sleep type %#x => %04x\n",
96 		       slp_typb, pm1b_cnt );
97 		outw ( ( ACPI_PM1_CNT_SLP_TYP ( slp_typb ) |
98 			 ACPI_PM1_CNT_SLP_EN ), pm1b_cnt );
99 	}
100 
101 	/* On some systems, execution will continue briefly.  Delay to
102 	 * avoid potentially confusing log messages.
103 	 */
104 	mdelay ( 1000 );
105 
106 	DBGC ( colour, "ACPI power off failed\n" );
107 	return -EPROTO;
108 }
109