1 /** @file
2 Produces the Legacy Region Protocol.
3
4 This generic implementation of the Legacy Region Protocol does not actually
5 perform any lock/unlock operations. This module may be used on platforms
6 that do not provide HW locking of the legacy memory regions. It can also
7 be used as a template driver for implementing the Legacy Region Protocol on
8 a platform that does support HW locking of the legacy memory regions.
9
10 Copyright (c) 2009, Intel Corporation. All rights reserved.<BR>
11 This program and the accompanying materials
12 are licensed and made available under the terms and conditions of the BSD License
13 which accompanies this distribution. The full text of the license may be found at
14 http://opensource.org/licenses/bsd-license.php
15
16 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
17 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
18
19 **/
20
21 #include <PiDxe.h>
22 #include <Protocol/LegacyRegion.h>
23 #include <Library/DebugLib.h>
24 #include <Library/UefiBootServicesTableLib.h>
25
26 /**
27 Sets hardware to decode or not decode a region.
28
29 @param This Indicates the EFI_LEGACY_REGION_PROTOCOL instance
30 @param Start Start of region to decode.
31 @param Length Size in bytes of the region.
32 @param On Decode/nondecode flag.
33
34 @retval EFI_SUCCESS Decode range successfully changed.
35
36 **/
37 EFI_STATUS
38 EFIAPI
LegacyRegionDecode(IN EFI_LEGACY_REGION_PROTOCOL * This,IN UINT32 Start,IN UINT32 Length,IN BOOLEAN * On)39 LegacyRegionDecode (
40 IN EFI_LEGACY_REGION_PROTOCOL *This,
41 IN UINT32 Start,
42 IN UINT32 Length,
43 IN BOOLEAN *On
44 )
45 {
46 return EFI_SUCCESS;
47 }
48
49 /**
50 Sets a region to read only.
51
52 @param This Indicates the EFI_LEGACY_REGION_PROTOCOL instance
53 @param Start Start of region to lock.
54 @param Length Size in bytes of the region.
55 @param Granularity Lock attribute affects this granularity in bytes.
56
57 @retval EFI_SUCCESS The region was made read only.
58
59 **/
60 EFI_STATUS
61 EFIAPI
LegacyRegionLock(IN EFI_LEGACY_REGION_PROTOCOL * This,IN UINT32 Start,IN UINT32 Length,OUT UINT32 * Granularity OPTIONAL)62 LegacyRegionLock (
63 IN EFI_LEGACY_REGION_PROTOCOL *This,
64 IN UINT32 Start,
65 IN UINT32 Length,
66 OUT UINT32 *Granularity OPTIONAL
67 )
68 {
69 return EFI_SUCCESS;
70 }
71
72 /**
73 Sets a region to read only and ensures that flash is locked from being
74 inadvertently modified.
75
76 @param This Indicates the EFI_LEGACY_REGION_PROTOCOL instance
77 @param Start Start of region to lock.
78 @param Length Size in bytes of the region.
79 @param Granularity Lock attribute affects this granularity in bytes.
80
81 @retval EFI_SUCCESS The region was made read only and flash is locked.
82
83 **/
84 EFI_STATUS
85 EFIAPI
LegacyRegionBootLock(IN EFI_LEGACY_REGION_PROTOCOL * This,IN UINT32 Start,IN UINT32 Length,OUT UINT32 * Granularity OPTIONAL)86 LegacyRegionBootLock (
87 IN EFI_LEGACY_REGION_PROTOCOL *This,
88 IN UINT32 Start,
89 IN UINT32 Length,
90 OUT UINT32 *Granularity OPTIONAL
91 )
92 {
93 return EFI_SUCCESS;
94 }
95
96 /**
97 Sets a region to read-write.
98
99 @param This Indicates the EFI_LEGACY_REGION_PROTOCOL instance
100 @param Start Start of region to lock.
101 @param Length Size in bytes of the region.
102 @param Granularity Lock attribute affects this granularity in bytes.
103
104 @retval EFI_SUCCESS The region was successfully made read-write.
105
106 **/
107 EFI_STATUS
108 EFIAPI
LegacyRegionUnlock(IN EFI_LEGACY_REGION_PROTOCOL * This,IN UINT32 Start,IN UINT32 Length,OUT UINT32 * Granularity OPTIONAL)109 LegacyRegionUnlock (
110 IN EFI_LEGACY_REGION_PROTOCOL *This,
111 IN UINT32 Start,
112 IN UINT32 Length,
113 OUT UINT32 *Granularity OPTIONAL
114 )
115 {
116 return EFI_SUCCESS;
117 }
118
119 //
120 // Module global for the handle the Legacy Region Protocol is installed
121 //
122 EFI_HANDLE mLegacyRegionHandle = NULL;
123
124 //
125 // Module global for the Legacy Region Protocol instance that is installed onto
126 // mLegacyRegionHandle
127 //
128 EFI_LEGACY_REGION_PROTOCOL mLegacyRegion = {
129 LegacyRegionDecode,
130 LegacyRegionLock,
131 LegacyRegionBootLock,
132 LegacyRegionUnlock
133 };
134
135 /**
136 The user Entry Point for module LegacyRegionDxe. The user code starts with this function.
137
138 @param[in] ImageHandle The firmware allocated handle for the EFI image.
139 @param[in] SystemTable A pointer to the EFI System Table.
140
141 @retval EFI_SUCCESS The entry point is executed successfully.
142 @retval other Some error occurs when executing this entry point.
143
144 **/
145 EFI_STATUS
146 EFIAPI
LegacyRegionInstall(IN EFI_HANDLE ImageHandle,IN EFI_SYSTEM_TABLE * SystemTable)147 LegacyRegionInstall (
148 IN EFI_HANDLE ImageHandle,
149 IN EFI_SYSTEM_TABLE *SystemTable
150 )
151 {
152 EFI_STATUS Status;
153
154 //
155 // Make sure the Legacy Region Protocol is not already installed in the system
156 //
157 ASSERT_PROTOCOL_ALREADY_INSTALLED (NULL, &gEfiLegacyRegionProtocolGuid);
158
159 //
160 // Install the protocol on a new handle.
161 //
162 Status = gBS->InstallMultipleProtocolInterfaces (
163 &mLegacyRegionHandle,
164 &gEfiLegacyRegionProtocolGuid, &mLegacyRegion,
165 NULL
166 );
167 ASSERT_EFI_ERROR (Status);
168
169 return Status;
170 }
171