1/* sfi_acpi.c Simple Firmware Interface - ACPI extensions */ 2 3/* 4 5 This file is provided under a dual BSD/GPLv2 license. When using or 6 redistributing this file, you may do so under either license. 7 8 GPL LICENSE SUMMARY 9 10 Copyright(c) 2009 Intel Corporation. All rights reserved. 11 12 This program is free software; you can redistribute it and/or modify 13 it under the terms of version 2 of the GNU General Public License as 14 published by the Free Software Foundation. 15 16 This program is distributed in the hope that it will be useful, but 17 WITHOUT ANY WARRANTY; without even the implied warranty of 18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 19 General Public License for more details. 20 21 You should have received a copy of the GNU General Public License 22 along with this program; if not, write to the Free Software 23 Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. 24 The full GNU General Public License is included in this distribution 25 in the file called LICENSE.GPL. 26 27 BSD LICENSE 28 29 Copyright(c) 2009 Intel Corporation. All rights reserved. 30 31 Redistribution and use in source and binary forms, with or without 32 modification, are permitted provided that the following conditions 33 are met: 34 35 * Redistributions of source code must retain the above copyright 36 notice, this list of conditions and the following disclaimer. 37 * Redistributions in binary form must reproduce the above copyright 38 notice, this list of conditions and the following disclaimer in 39 the documentation and/or other materials provided with the 40 distribution. 41 * Neither the name of Intel Corporation nor the names of its 42 contributors may be used to endorse or promote products derived 43 from this software without specific prior written permission. 44 45 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 46 "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 47 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 48 A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 49 OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 50 SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 51 LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 52 DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 53 THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 54 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 55 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 56 57*/ 58 59#define KMSG_COMPONENT "SFI" 60#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 61 62#include <linux/kernel.h> 63#include <acpi/acpi.h> 64 65#include <linux/sfi.h> 66#include "sfi_core.h" 67 68/* 69 * SFI can access ACPI-defined tables via an optional ACPI XSDT. 70 * 71 * This allows re-use, and avoids re-definition, of standard tables. 72 * For example, the "MCFG" table is defined by PCI, reserved by ACPI, 73 * and is expected to be present many SFI-only systems. 74 */ 75 76static struct acpi_table_xsdt *xsdt_va __read_mostly; 77 78#define XSDT_GET_NUM_ENTRIES(ptable, entry_type) \ 79 ((ptable->header.length - sizeof(struct acpi_table_header)) / \ 80 (sizeof(entry_type))) 81 82static inline struct sfi_table_header *acpi_to_sfi_th( 83 struct acpi_table_header *th) 84{ 85 return (struct sfi_table_header *)th; 86} 87 88static inline struct acpi_table_header *sfi_to_acpi_th( 89 struct sfi_table_header *th) 90{ 91 return (struct acpi_table_header *)th; 92} 93 94/* 95 * sfi_acpi_parse_xsdt() 96 * 97 * Parse the ACPI XSDT for later access by sfi_acpi_table_parse(). 98 */ 99static int __init sfi_acpi_parse_xsdt(struct sfi_table_header *th) 100{ 101 struct sfi_table_key key = SFI_ANY_KEY; 102 int tbl_cnt, i; 103 void *ret; 104 105 xsdt_va = (struct acpi_table_xsdt *)th; 106 tbl_cnt = XSDT_GET_NUM_ENTRIES(xsdt_va, u64); 107 for (i = 0; i < tbl_cnt; i++) { 108 ret = sfi_check_table(xsdt_va->table_offset_entry[i], &key); 109 if (IS_ERR(ret)) { 110 disable_sfi(); 111 return -1; 112 } 113 } 114 115 return 0; 116} 117 118int __init sfi_acpi_init(void) 119{ 120 struct sfi_table_key xsdt_key = { .sig = SFI_SIG_XSDT }; 121 122 sfi_table_parse(SFI_SIG_XSDT, NULL, NULL, sfi_acpi_parse_xsdt); 123 124 /* Only call the get_table to keep the table mapped */ 125 xsdt_va = (struct acpi_table_xsdt *)sfi_get_table(&xsdt_key); 126 return 0; 127} 128 129static struct acpi_table_header *sfi_acpi_get_table(struct sfi_table_key *key) 130{ 131 u32 tbl_cnt, i; 132 void *ret; 133 134 tbl_cnt = XSDT_GET_NUM_ENTRIES(xsdt_va, u64); 135 for (i = 0; i < tbl_cnt; i++) { 136 ret = sfi_check_table(xsdt_va->table_offset_entry[i], key); 137 if (!IS_ERR(ret) && ret) 138 return sfi_to_acpi_th(ret); 139 } 140 141 return NULL; 142} 143 144static void sfi_acpi_put_table(struct acpi_table_header *table) 145{ 146 sfi_put_table(acpi_to_sfi_th(table)); 147} 148 149/* 150 * sfi_acpi_table_parse() 151 * 152 * Find specified table in XSDT, run handler on it and return its return value 153 */ 154int sfi_acpi_table_parse(char *signature, char *oem_id, char *oem_table_id, 155 int(*handler)(struct acpi_table_header *)) 156{ 157 struct acpi_table_header *table = NULL; 158 struct sfi_table_key key; 159 int ret = 0; 160 161 if (sfi_disabled) 162 return -1; 163 164 key.sig = signature; 165 key.oem_id = oem_id; 166 key.oem_table_id = oem_table_id; 167 168 table = sfi_acpi_get_table(&key); 169 if (!table) 170 return -EINVAL; 171 172 ret = handler(table); 173 sfi_acpi_put_table(table); 174 return ret; 175} 176