302 lines
8.7 KiB
C
302 lines
8.7 KiB
C
|
/******************************************************************************
|
||
|
*
|
||
|
* Module Name: tbxfroot - Find the root ACPI table (RSDT)
|
||
|
*
|
||
|
*****************************************************************************/
|
||
|
|
||
|
/*
|
||
|
* Copyright (C) 2000 - 2016, Intel Corp.
|
||
|
* All rights reserved.
|
||
|
*
|
||
|
* Redistribution and use in source and binary forms, with or without
|
||
|
* modification, are permitted provided that the following conditions
|
||
|
* are met:
|
||
|
* 1. Redistributions of source code must retain the above copyright
|
||
|
* notice, this list of conditions, and the following disclaimer,
|
||
|
* without modification.
|
||
|
* 2. Redistributions in binary form must reproduce at minimum a disclaimer
|
||
|
* substantially similar to the "NO WARRANTY" disclaimer below
|
||
|
* ("Disclaimer") and any redistribution must be conditioned upon
|
||
|
* including a substantially similar Disclaimer requirement for further
|
||
|
* binary redistribution.
|
||
|
* 3. Neither the names of the above-listed copyright holders nor the names
|
||
|
* of any contributors may be used to endorse or promote products derived
|
||
|
* from this software without specific prior written permission.
|
||
|
*
|
||
|
* Alternatively, this software may be distributed under the terms of the
|
||
|
* GNU General Public License ("GPL") version 2 as published by the Free
|
||
|
* Software Foundation.
|
||
|
*
|
||
|
* NO WARRANTY
|
||
|
* 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 MERCHANTIBILITY AND FITNESS FOR
|
||
|
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
||
|
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR 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 DAMAGES.
|
||
|
*/
|
||
|
|
||
|
#include <acpi/acpi.h>
|
||
|
#include "accommon.h"
|
||
|
#include "actables.h"
|
||
|
|
||
|
#define _COMPONENT ACPI_TABLES
|
||
|
ACPI_MODULE_NAME("tbxfroot")
|
||
|
|
||
|
/*******************************************************************************
|
||
|
*
|
||
|
* FUNCTION: acpi_tb_get_rsdp_length
|
||
|
*
|
||
|
* PARAMETERS: rsdp - Pointer to RSDP
|
||
|
*
|
||
|
* RETURN: Table length
|
||
|
*
|
||
|
* DESCRIPTION: Get the length of the RSDP
|
||
|
*
|
||
|
******************************************************************************/
|
||
|
u32 acpi_tb_get_rsdp_length(struct acpi_table_rsdp *rsdp)
|
||
|
{
|
||
|
|
||
|
if (!ACPI_VALIDATE_RSDP_SIG(rsdp->signature)) {
|
||
|
|
||
|
/* BAD Signature */
|
||
|
|
||
|
return (0);
|
||
|
}
|
||
|
|
||
|
/* "Length" field is available if table version >= 2 */
|
||
|
|
||
|
if (rsdp->revision >= 2) {
|
||
|
return (rsdp->length);
|
||
|
} else {
|
||
|
return (ACPI_RSDP_CHECKSUM_LENGTH);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/*******************************************************************************
|
||
|
*
|
||
|
* FUNCTION: acpi_tb_validate_rsdp
|
||
|
*
|
||
|
* PARAMETERS: rsdp - Pointer to unvalidated RSDP
|
||
|
*
|
||
|
* RETURN: Status
|
||
|
*
|
||
|
* DESCRIPTION: Validate the RSDP (ptr)
|
||
|
*
|
||
|
******************************************************************************/
|
||
|
|
||
|
acpi_status acpi_tb_validate_rsdp(struct acpi_table_rsdp *rsdp)
|
||
|
{
|
||
|
|
||
|
/*
|
||
|
* The signature and checksum must both be correct
|
||
|
*
|
||
|
* Note: Sometimes there exists more than one RSDP in memory; the valid
|
||
|
* RSDP has a valid checksum, all others have an invalid checksum.
|
||
|
*/
|
||
|
if (!ACPI_VALIDATE_RSDP_SIG(rsdp->signature)) {
|
||
|
|
||
|
/* Nope, BAD Signature */
|
||
|
|
||
|
return (AE_BAD_SIGNATURE);
|
||
|
}
|
||
|
|
||
|
/* Check the standard checksum */
|
||
|
|
||
|
if (acpi_tb_checksum((u8 *) rsdp, ACPI_RSDP_CHECKSUM_LENGTH) != 0) {
|
||
|
return (AE_BAD_CHECKSUM);
|
||
|
}
|
||
|
|
||
|
/* Check extended checksum if table version >= 2 */
|
||
|
|
||
|
if ((rsdp->revision >= 2) &&
|
||
|
(acpi_tb_checksum((u8 *) rsdp, ACPI_RSDP_XCHECKSUM_LENGTH) != 0)) {
|
||
|
return (AE_BAD_CHECKSUM);
|
||
|
}
|
||
|
|
||
|
return (AE_OK);
|
||
|
}
|
||
|
|
||
|
/*******************************************************************************
|
||
|
*
|
||
|
* FUNCTION: acpi_find_root_pointer
|
||
|
*
|
||
|
* PARAMETERS: table_address - Where the table pointer is returned
|
||
|
*
|
||
|
* RETURN: Status, RSDP physical address
|
||
|
*
|
||
|
* DESCRIPTION: Search lower 1Mbyte of memory for the root system descriptor
|
||
|
* pointer structure. If it is found, set *RSDP to point to it.
|
||
|
*
|
||
|
* NOTE1: The RSDP must be either in the first 1K of the Extended
|
||
|
* BIOS Data Area or between E0000 and FFFFF (From ACPI Spec.)
|
||
|
* Only a 32-bit physical address is necessary.
|
||
|
*
|
||
|
* NOTE2: This function is always available, regardless of the
|
||
|
* initialization state of the rest of ACPI.
|
||
|
*
|
||
|
******************************************************************************/
|
||
|
|
||
|
acpi_status ACPI_INIT_FUNCTION
|
||
|
acpi_find_root_pointer(acpi_physical_address *table_address)
|
||
|
{
|
||
|
u8 *table_ptr;
|
||
|
u8 *mem_rover;
|
||
|
u32 physical_address;
|
||
|
|
||
|
ACPI_FUNCTION_TRACE(acpi_find_root_pointer);
|
||
|
|
||
|
/* 1a) Get the location of the Extended BIOS Data Area (EBDA) */
|
||
|
|
||
|
table_ptr = acpi_os_map_memory((acpi_physical_address)
|
||
|
ACPI_EBDA_PTR_LOCATION,
|
||
|
ACPI_EBDA_PTR_LENGTH);
|
||
|
if (!table_ptr) {
|
||
|
ACPI_ERROR((AE_INFO,
|
||
|
"Could not map memory at 0x%8.8X for length %u",
|
||
|
ACPI_EBDA_PTR_LOCATION, ACPI_EBDA_PTR_LENGTH));
|
||
|
|
||
|
return_ACPI_STATUS(AE_NO_MEMORY);
|
||
|
}
|
||
|
|
||
|
ACPI_MOVE_16_TO_32(&physical_address, table_ptr);
|
||
|
|
||
|
/* Convert segment part to physical address */
|
||
|
|
||
|
physical_address <<= 4;
|
||
|
acpi_os_unmap_memory(table_ptr, ACPI_EBDA_PTR_LENGTH);
|
||
|
|
||
|
/* EBDA present? */
|
||
|
|
||
|
if (physical_address > 0x400) {
|
||
|
/*
|
||
|
* 1b) Search EBDA paragraphs (EBDA is required to be a
|
||
|
* minimum of 1K length)
|
||
|
*/
|
||
|
table_ptr = acpi_os_map_memory((acpi_physical_address)
|
||
|
physical_address,
|
||
|
ACPI_EBDA_WINDOW_SIZE);
|
||
|
if (!table_ptr) {
|
||
|
ACPI_ERROR((AE_INFO,
|
||
|
"Could not map memory at 0x%8.8X for length %u",
|
||
|
physical_address, ACPI_EBDA_WINDOW_SIZE));
|
||
|
|
||
|
return_ACPI_STATUS(AE_NO_MEMORY);
|
||
|
}
|
||
|
|
||
|
mem_rover =
|
||
|
acpi_tb_scan_memory_for_rsdp(table_ptr,
|
||
|
ACPI_EBDA_WINDOW_SIZE);
|
||
|
acpi_os_unmap_memory(table_ptr, ACPI_EBDA_WINDOW_SIZE);
|
||
|
|
||
|
if (mem_rover) {
|
||
|
|
||
|
/* Return the physical address */
|
||
|
|
||
|
physical_address +=
|
||
|
(u32) ACPI_PTR_DIFF(mem_rover, table_ptr);
|
||
|
|
||
|
*table_address =
|
||
|
(acpi_physical_address)physical_address;
|
||
|
return_ACPI_STATUS(AE_OK);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* 2) Search upper memory: 16-byte boundaries in E0000h-FFFFFh
|
||
|
*/
|
||
|
table_ptr = acpi_os_map_memory((acpi_physical_address)
|
||
|
ACPI_HI_RSDP_WINDOW_BASE,
|
||
|
ACPI_HI_RSDP_WINDOW_SIZE);
|
||
|
|
||
|
if (!table_ptr) {
|
||
|
ACPI_ERROR((AE_INFO,
|
||
|
"Could not map memory at 0x%8.8X for length %u",
|
||
|
ACPI_HI_RSDP_WINDOW_BASE,
|
||
|
ACPI_HI_RSDP_WINDOW_SIZE));
|
||
|
|
||
|
return_ACPI_STATUS(AE_NO_MEMORY);
|
||
|
}
|
||
|
|
||
|
mem_rover =
|
||
|
acpi_tb_scan_memory_for_rsdp(table_ptr, ACPI_HI_RSDP_WINDOW_SIZE);
|
||
|
acpi_os_unmap_memory(table_ptr, ACPI_HI_RSDP_WINDOW_SIZE);
|
||
|
|
||
|
if (mem_rover) {
|
||
|
|
||
|
/* Return the physical address */
|
||
|
|
||
|
physical_address = (u32)
|
||
|
(ACPI_HI_RSDP_WINDOW_BASE +
|
||
|
ACPI_PTR_DIFF(mem_rover, table_ptr));
|
||
|
|
||
|
*table_address = (acpi_physical_address)physical_address;
|
||
|
return_ACPI_STATUS(AE_OK);
|
||
|
}
|
||
|
|
||
|
/* A valid RSDP was not found */
|
||
|
|
||
|
ACPI_BIOS_ERROR((AE_INFO, "A valid RSDP was not found"));
|
||
|
return_ACPI_STATUS(AE_NOT_FOUND);
|
||
|
}
|
||
|
|
||
|
ACPI_EXPORT_SYMBOL_INIT(acpi_find_root_pointer)
|
||
|
|
||
|
/*******************************************************************************
|
||
|
*
|
||
|
* FUNCTION: acpi_tb_scan_memory_for_rsdp
|
||
|
*
|
||
|
* PARAMETERS: start_address - Starting pointer for search
|
||
|
* length - Maximum length to search
|
||
|
*
|
||
|
* RETURN: Pointer to the RSDP if found, otherwise NULL.
|
||
|
*
|
||
|
* DESCRIPTION: Search a block of memory for the RSDP signature
|
||
|
*
|
||
|
******************************************************************************/
|
||
|
u8 *acpi_tb_scan_memory_for_rsdp(u8 *start_address, u32 length)
|
||
|
{
|
||
|
acpi_status status;
|
||
|
u8 *mem_rover;
|
||
|
u8 *end_address;
|
||
|
|
||
|
ACPI_FUNCTION_TRACE(tb_scan_memory_for_rsdp);
|
||
|
|
||
|
end_address = start_address + length;
|
||
|
|
||
|
/* Search from given start address for the requested length */
|
||
|
|
||
|
for (mem_rover = start_address; mem_rover < end_address;
|
||
|
mem_rover += ACPI_RSDP_SCAN_STEP) {
|
||
|
|
||
|
/* The RSDP signature and checksum must both be correct */
|
||
|
|
||
|
status =
|
||
|
acpi_tb_validate_rsdp(ACPI_CAST_PTR
|
||
|
(struct acpi_table_rsdp, mem_rover));
|
||
|
if (ACPI_SUCCESS(status)) {
|
||
|
|
||
|
/* Sig and checksum valid, we have found a real RSDP */
|
||
|
|
||
|
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
|
||
|
"RSDP located at physical address %p\n",
|
||
|
mem_rover));
|
||
|
return_PTR(mem_rover);
|
||
|
}
|
||
|
|
||
|
/* No sig match or bad checksum, keep searching */
|
||
|
}
|
||
|
|
||
|
/* Searched entire block, no RSDP was found */
|
||
|
|
||
|
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
|
||
|
"Searched entire block from %p, valid RSDP was not found\n",
|
||
|
start_address));
|
||
|
return_PTR(NULL);
|
||
|
}
|