freebsd-dev/sys/amd64/acpica/OsdEnvironment.c
Marcel Moolenaar 91c71b46ed Export the physical address of the RSDP to userland by means
of the `machdep.acpi_root' sysctl. This is required on ia64
because the root pointer hardly ever, if at all, lives in the
first MB of memory and also because scanning the first MB of
memory can cause machine checks.
This provides a save and reliable way for ACPI tools to work
with the tables if ACPI support is present in the kernel. On
ia64 ACPI is non-optional.
2002-12-18 08:47:07 +00:00

80 lines
2.3 KiB
C

/*-
* Copyright (c) 2000,2001 Michael Smith
* Copyright (c) 2000 BSDi
* 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.
* 2. 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*
* $FreeBSD$
*/
/*
* 6.1 : Environmental support
*/
#include <sys/types.h>
#include <sys/linker_set.h>
#include <sys/sysctl.h>
#include "acpi.h"
#include <machine/pc/bios.h>
u_long i386_acpi_root;
SYSCTL_ULONG(_machdep, OID_AUTO, acpi_root, CTLFLAG_RD, &i386_acpi_root, 0,
"The physical address of the RSDP");
ACPI_STATUS
AcpiOsInitialize(void)
{
return(0);
}
ACPI_STATUS
AcpiOsTerminate(void)
{
return(0);
}
ACPI_STATUS
AcpiOsGetRootPointer(UINT32 Flags, ACPI_POINTER *RsdpPhysicalAddress)
{
ACPI_POINTER ptr;
ACPI_STATUS status;
if (i386_acpi_root == 0) {
/*
* The loader passes the physical address at which it found the
* RSDP in a hint. We could recover this rather than searching
* manually here.
*/
status = AcpiFindRootPointer(Flags, &ptr);
if (status == AE_OK)
i386_acpi_root = ptr.Pointer.Physical;
} else
status = AE_OK;
RsdpPhysicalAddress->PointerType = ACPI_PHYSICAL_POINTER;
RsdpPhysicalAddress->Pointer.Physical = i386_acpi_root;
return (status);
}