audk/MdePkg/Library/UefiSalLib/UefiSalLib.c

140 lines
4.3 KiB
C

/** @file
SAL Library implementation retrieving the SAL Entry Point from the SAL System Table
register in the EFI System Configuration Table.
Copyright (c) 2007 - 2010, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials are
licensed and made available under the terms and conditions of
the BSD License which accompanies this distribution. The full
text of the license may be found at
http://opensource.org/licenses/bsd-license.php.
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
**/
#include <PiDxe.h>
#include <IndustryStandard/Sal.h>
#include <Library/SalLib.h>
#include <Library/UefiLib.h>
#include <Library/DebugLib.h>
#include <Guid/SalSystemTable.h>
EFI_PLABEL mPlabel;
SAL_PROC mSalProcEntry;
/**
Makes a SAL procedure call.
This is a wrapper function to make a SAL procedure call.
No parameter checking is performed on the 8 input parameters,
but there are some common rules that the caller should follow
when making a SAL call. Any address passed to SAL as buffers
for return parameters must be 8-byte aligned. Unaligned
addresses may cause undefined results. For those parameters
defined as reserved or some fields defined as reserved must be
zero filled or the invalid argument return value may be returned
or undefined result may occur during the execution of the procedure.
This function is only available on IPF.
@param Index The SAL procedure Index number.
@param Arg2 The 2nd parameter for SAL procedure calls.
@param Arg3 The 3rd parameter for SAL procedure calls.
@param Arg4 The 4th parameter for SAL procedure calls.
@param Arg5 The 5th parameter for SAL procedure calls.
@param Arg6 The 6th parameter for SAL procedure calls.
@param Arg7 The 7th parameter for SAL procedure calls.
@param Arg8 The 8th parameter for SAL procedure calls.
@return SAL returned registers.
**/
SAL_RETURN_REGS
EFIAPI
SalCall (
IN UINT64 Index,
IN UINT64 Arg2,
IN UINT64 Arg3,
IN UINT64 Arg4,
IN UINT64 Arg5,
IN UINT64 Arg6,
IN UINT64 Arg7,
IN UINT64 Arg8
)
{
//
// mSalProcEntry is initialized in library constructor as SAL entry.
//
return mSalProcEntry(
Index,
Arg2,
Arg3,
Arg4,
Arg5,
Arg6,
Arg7,
Arg8
);
}
/**
The constructor function of UEFI SAL Lib.
The constructor function looks up the SAL System Table in the EFI System Configuration
Table. Once the SAL System Table is found, the SAL Entry Point in the SAL System Table
will be derived and stored into a global variable for library usage.
It will ASSERT() if the SAL System Table cannot be found or the data in the SAL System
Table is not the valid data.
@param ImageHandle The firmware allocated handle for the EFI image.
@param SystemTable A pointer to the EFI System Table.
@retval EFI_SUCCESS The constructor always returns EFI_SUCCESS.
**/
EFI_STATUS
EFIAPI
UefiSalLibConstructor (
IN EFI_HANDLE ImageHandle,
IN EFI_SYSTEM_TABLE *SystemTable
)
{
EFI_STATUS Status;
SAL_ST_ENTRY_POINT_DESCRIPTOR *SalStEntryDes;
SAL_SYSTEM_TABLE_HEADER *SalSystemTable;
Status = EfiGetSystemConfigurationTable (
&gEfiSalSystemTableGuid,
(VOID **) &SalSystemTable
);
ASSERT_EFI_ERROR (Status);
ASSERT (SalSystemTable != NULL);
//
// Check the first entry of SAL System Table,
// because the SAL entry is in ascending order with the entry type,
// the type 0 entry should be the first if exist.
//
SalStEntryDes = (SAL_ST_ENTRY_POINT_DESCRIPTOR *)(SalSystemTable + 1);
//
// Assure the SAL ENTRY Type is 0
//
ASSERT (SalStEntryDes->Type == EFI_SAL_ST_ENTRY_POINT);
mPlabel.EntryPoint = SalStEntryDes->SalProcEntry;
mPlabel.GP = SalStEntryDes->SalGlobalDataPointer;
//
// Make sure the EntryPoint has the valid value
//
ASSERT ((mPlabel.EntryPoint != 0) && (mPlabel.GP != 0));
mSalProcEntry = (SAL_PROC)((UINT64)&(mPlabel.EntryPoint));
return EFI_SUCCESS;
}