1/** @file
2  SAL Library implementation retrieving the SAL Entry Point from the SAL System Table
3  register in the EFI System Configuration Table.
4
5  Copyright (c) 2007 - 2010, Intel Corporation. All rights reserved.<BR>
6  This program and the accompanying materials are
7  licensed and made available under the terms and conditions of
8  the BSD License which accompanies this distribution.  The full
9  text of the license may be found at
10  http://opensource.org/licenses/bsd-license.php.
11
12  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
13  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
14
15**/
16
17#include <PiDxe.h>
18#include <IndustryStandard/Sal.h>
19
20#include <Library/SalLib.h>
21#include <Library/UefiLib.h>
22#include <Library/DebugLib.h>
23
24#include <Guid/SalSystemTable.h>
25
26EFI_PLABEL       mPlabel;
27SAL_PROC         mSalProcEntry;
28
29/**
30  Makes a SAL procedure call.
31
32  This is a wrapper function to make a SAL procedure call.
33  No parameter checking is performed on the 8 input parameters,
34  but there are some common rules that the caller should follow
35  when making a SAL call.  Any address passed to SAL as buffers
36  for return parameters must be 8-byte aligned.  Unaligned
37  addresses may cause undefined results.  For those parameters
38  defined as reserved or some fields defined as reserved must be
39  zero filled or the invalid argument return value may be returned
40  or undefined result may occur during the execution of the procedure.
41  This function is only available on IPF.
42
43  @param  Index       The SAL procedure Index number.
44  @param  Arg2        The 2nd parameter for SAL procedure calls.
45  @param  Arg3        The 3rd parameter for SAL procedure calls.
46  @param  Arg4        The 4th parameter for SAL procedure calls.
47  @param  Arg5        The 5th parameter for SAL procedure calls.
48  @param  Arg6        The 6th parameter for SAL procedure calls.
49  @param  Arg7        The 7th parameter for SAL procedure calls.
50  @param  Arg8        The 8th parameter for SAL procedure calls.
51
52  @return SAL returned registers.
53
54**/
55SAL_RETURN_REGS
56EFIAPI
57SalCall (
58  IN UINT64  Index,
59  IN UINT64  Arg2,
60  IN UINT64  Arg3,
61  IN UINT64  Arg4,
62  IN UINT64  Arg5,
63  IN UINT64  Arg6,
64  IN UINT64  Arg7,
65  IN UINT64  Arg8
66  )
67{
68  //
69  // mSalProcEntry is initialized in library constructor as SAL entry.
70  //
71  return mSalProcEntry(
72           Index,
73           Arg2,
74           Arg3,
75           Arg4,
76           Arg5,
77           Arg6,
78           Arg7,
79           Arg8
80           );
81
82}
83
84/**
85  The constructor function of UEFI SAL Lib.
86
87  The constructor function looks up the SAL System Table in the EFI System Configuration
88  Table. Once the SAL System Table is found, the SAL Entry Point in the SAL System Table
89  will be derived and stored into a global variable for library usage.
90  It will ASSERT() if the SAL System Table cannot be found or the data in the SAL System
91  Table is not the valid data.
92
93  @param  ImageHandle   The firmware allocated handle for the EFI image.
94  @param  SystemTable   A pointer to the EFI System Table.
95
96  @retval EFI_SUCCESS   The constructor always returns EFI_SUCCESS.
97
98**/
99EFI_STATUS
100EFIAPI
101UefiSalLibConstructor (
102  IN EFI_HANDLE        ImageHandle,
103  IN EFI_SYSTEM_TABLE  *SystemTable
104  )
105{
106  EFI_STATUS                     Status;
107  SAL_ST_ENTRY_POINT_DESCRIPTOR  *SalStEntryDes;
108  SAL_SYSTEM_TABLE_HEADER        *SalSystemTable;
109
110  Status = EfiGetSystemConfigurationTable (
111             &gEfiSalSystemTableGuid,
112             (VOID **) &SalSystemTable
113             );
114  ASSERT_EFI_ERROR (Status);
115  ASSERT (SalSystemTable != NULL);
116
117  //
118  // Check the first entry of SAL System Table,
119  // because the SAL entry is in ascending order with the entry type,
120  // the type 0 entry should be the first if exist.
121  //
122  SalStEntryDes = (SAL_ST_ENTRY_POINT_DESCRIPTOR *)(SalSystemTable + 1);
123
124  //
125  // Assure the SAL ENTRY Type is 0
126  //
127  ASSERT (SalStEntryDes->Type == EFI_SAL_ST_ENTRY_POINT);
128
129  mPlabel.EntryPoint = SalStEntryDes->SalProcEntry;
130  mPlabel.GP = SalStEntryDes->SalGlobalDataPointer;
131  //
132  // Make sure the EntryPoint has the valid value
133  //
134  ASSERT ((mPlabel.EntryPoint != 0) && (mPlabel.GP != 0));
135
136  mSalProcEntry = (SAL_PROC)((UINT64)&(mPlabel.EntryPoint));
137
138  return EFI_SUCCESS;
139}
140