diff options
Diffstat (limited to 'drivers/sfi')
| -rw-r--r-- | drivers/sfi/sfi_acpi.c | 175 |
1 files changed, 175 insertions, 0 deletions
diff --git a/drivers/sfi/sfi_acpi.c b/drivers/sfi/sfi_acpi.c new file mode 100644 index 00000000000..34aba30eb84 --- /dev/null +++ b/drivers/sfi/sfi_acpi.c @@ -0,0 +1,175 @@ +/* sfi_acpi.c Simple Firmware Interface - ACPI extensions */ + +/* + + This file is provided under a dual BSD/GPLv2 license. When using or + redistributing this file, you may do so under either license. + + GPL LICENSE SUMMARY + + Copyright(c) 2009 Intel Corporation. All rights reserved. + + This program is free software; you can redistribute it and/or modify + it under the terms of version 2 of the GNU General Public License as + published by the Free Software Foundation. + + This program is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + The full GNU General Public License is included in this distribution + in the file called LICENSE.GPL. + + BSD LICENSE + + Copyright(c) 2009 Intel Corporation. All rights reserved. + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions + are met: + + * Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + * Redistributions in binary form must reproduce the above copyright + notice, this list of conditions and the following disclaimer in + the documentation and/or other materials provided with the + distribution. + * Neither the name of Intel Corporation nor the names of its + contributors may be used to endorse or promote products derived + from this software without specific prior written permission. + + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +*/ + +#define KMSG_COMPONENT "SFI" +#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt + +#include <linux/kernel.h> +#include <acpi/acpi.h> + +#include <linux/sfi.h> +#include "sfi_core.h" + +/* + * SFI can access ACPI-defined tables via an optional ACPI XSDT. + * + * This allows re-use, and avoids re-definition, of standard tables. + * For example, the "MCFG" table is defined by PCI, reserved by ACPI, + * and is expected to be present many SFI-only systems. + */ + +static struct acpi_table_xsdt *xsdt_va __read_mostly; + +#define XSDT_GET_NUM_ENTRIES(ptable, entry_type) \ + ((ptable->header.length - sizeof(struct acpi_table_header)) / \ + (sizeof(entry_type))) + +static inline struct sfi_table_header *acpi_to_sfi_th( + struct acpi_table_header *th) +{ + return (struct sfi_table_header *)th; +} + +static inline struct acpi_table_header *sfi_to_acpi_th( + struct sfi_table_header *th) +{ + return (struct acpi_table_header *)th; +} + +/* + * sfi_acpi_parse_xsdt() + * + * Parse the ACPI XSDT for later access by sfi_acpi_table_parse(). + */ +static int __init sfi_acpi_parse_xsdt(struct sfi_table_header *th) +{ + struct sfi_table_key key = SFI_ANY_KEY; + int tbl_cnt, i; + void *ret; + + xsdt_va = (struct acpi_table_xsdt *)th; + tbl_cnt = XSDT_GET_NUM_ENTRIES(xsdt_va, u64); + for (i = 0; i < tbl_cnt; i++) { + ret = sfi_check_table(xsdt_va->table_offset_entry[i], &key); + if (IS_ERR(ret)) { + disable_sfi(); + return -1; + } + } + + return 0; +} + +int __init sfi_acpi_init(void) +{ + struct sfi_table_key xsdt_key = { .sig = SFI_SIG_XSDT }; + + sfi_table_parse(SFI_SIG_XSDT, NULL, NULL, sfi_acpi_parse_xsdt); + + /* Only call the get_table to keep the table mapped */ + xsdt_va = (struct acpi_table_xsdt *)sfi_get_table(&xsdt_key); + return 0; +} + +static struct acpi_table_header *sfi_acpi_get_table(struct sfi_table_key *key) +{ + u32 tbl_cnt, i; + void *ret; + + tbl_cnt = XSDT_GET_NUM_ENTRIES(xsdt_va, u64); + for (i = 0; i < tbl_cnt; i++) { + ret = sfi_check_table(xsdt_va->table_offset_entry[i], key); + if (!IS_ERR(ret) && ret) + return sfi_to_acpi_th(ret); + } + + return NULL; +} + +static void sfi_acpi_put_table(struct acpi_table_header *table) +{ + sfi_put_table(acpi_to_sfi_th(table)); +} + +/* + * sfi_acpi_table_parse() + * + * Find specified table in XSDT, run handler on it and return its return value + */ +int sfi_acpi_table_parse(char *signature, char *oem_id, char *oem_table_id, + int(*handler)(struct acpi_table_header *)) +{ + struct acpi_table_header *table = NULL; + struct sfi_table_key key; + int ret = 0; + + if (sfi_disabled) + return -1; + + key.sig = signature; + key.oem_id = oem_id; + key.oem_table_id = oem_table_id; + + table = sfi_acpi_get_table(&key); + if (!table) + return -EINVAL; + + ret = handler(table); + sfi_acpi_put_table(table); + return ret; +} |