1/*-
2 * Copyright (c) 2002 Mitsaru Iwasaki
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27/*
28 * ACPI Table interfaces
29 */
30
31#include <sys/cdefs.h>
32__FBSDID("$FreeBSD: head/sys/dev/acpica/Osd/OsdTable.c 148318 2005-07-22 23:10:02Z njl $");
33
34#include <sys/param.h>
35#include <sys/endian.h>
36#include <sys/kernel.h>
37#include <sys/linker.h>
38
39#include "acpi.h"
40#include <contrib/dev/acpica/actables.h>
41
42#undef _COMPONENT
43#define _COMPONENT ACPI_TABLES
44
45static char acpi_osname[128];
46TUNABLE_STR("hw.acpi.osname", acpi_osname, sizeof(acpi_osname));
47
48static struct {
49 ACPI_TABLE_HEADER_DEF
50 uint32_t no_op;
51} __packed fake_ssdt;
52
53ACPI_STATUS
54AcpiOsPredefinedOverride (
55 const ACPI_PREDEFINED_NAMES *InitVal,
56 ACPI_STRING *NewVal)
57{
58 if (InitVal == NULL || NewVal == NULL)
59 return (AE_BAD_PARAMETER);
60
61 *NewVal = NULL;
62 if (strncmp(InitVal->Name, "_OS_", 4) == 0 && strlen(acpi_osname) > 0) {
63 printf("ACPI: Overriding _OS definition with \"%s\"\n", acpi_osname);
64 *NewVal = acpi_osname;
65 }
66
67 return (AE_OK);
68}
69
70ACPI_STATUS
71AcpiOsTableOverride (
72 ACPI_TABLE_HEADER *ExistingTable,
73 ACPI_TABLE_HEADER **NewTable)
74{
75 caddr_t acpi_dsdt, p;
76
77 if (ExistingTable == NULL || NewTable == NULL)
78 return (AE_BAD_PARAMETER);
79
80 /* If we're not overriding the DSDT, just return. */
81 *NewTable = NULL;
82 if ((acpi_dsdt = preload_search_by_type("acpi_dsdt")) == NULL)
83 return (AE_OK);
84 if ((p = preload_search_info(acpi_dsdt, MODINFO_ADDR)) == NULL)
85 return (AE_OK);
86
87 /*
88 * Override the DSDT with the user's custom version. Override the
89 * contents of any SSDTs with a simple no-op table since the user's
90 * DSDT is expected to contain their contents as well.
91 */
92 if (strncmp(ExistingTable->Signature, "DSDT", 4) == 0) {
93 printf("ACPI: overriding DSDT/SSDT with custom table\n");
94 *NewTable = *(void **)p;
95 } else if (strncmp(ExistingTable->Signature, "SSDT", 4) == 0) {
96 if (fake_ssdt.Length == 0) {
97 sprintf(fake_ssdt.Signature, "%.4s", "SSDT");
98 fake_ssdt.Length = htole32(sizeof(fake_ssdt));
99 fake_ssdt.Revision = 2;
100 fake_ssdt.Checksum = 0;
101 sprintf(fake_ssdt.OemId, "%.6s", "FBSD ");
102 sprintf(fake_ssdt.OemTableId, "%.8s", "NullSSDT");
103 fake_ssdt.OemRevision = htole32(1);
104 sprintf(fake_ssdt.AslCompilerId, "%.4s", "FBSD");
105 fake_ssdt.AslCompilerRevision = htole32(1);
106 fake_ssdt.no_op = htole32(0x005c0310); /* Scope(\) */
107 fake_ssdt.Checksum -= AcpiTbChecksum(&fake_ssdt, sizeof(fake_ssdt));
108 }
109 *NewTable = (void *)&fake_ssdt;
110 }
111
112 return (AE_OK);
113}