1 /** @file
2 Implementation of the 6 PEI Ffs (FV) APIs in library form.
3
4 Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
5
6 This program and the accompanying materials
7 are licensed and made available under the terms and conditions of the BSD License
8 which accompanies this distribution. The full text of the license may be found at
9 http://opensource.org/licenses/bsd-license.php
10
11 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
12 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
13
14 **/
15
16 #include <PiPei.h>
17
18 #include <Library/BaseLib.h>
19 #include <Library/PrePiLib.h>
20 #include <Library/DebugLib.h>
21
22
23
24 /**
25 Allocates one or more 4KB pages of type EfiBootServicesData.
26
27 Allocates the number of 4KB pages of MemoryType and returns a pointer to the
28 allocated buffer. The buffer returned is aligned on a 4KB boundary. If Pages is 0, then NULL
29 is returned. If there is not enough memory remaining to satisfy the request, then NULL is
30 returned.
31
32 @param Pages The number of 4 KB pages to allocate.
33
34 @return A pointer to the allocated buffer or NULL if allocation fails.
35
36 **/
37 VOID *
38 EFIAPI
AllocatePages(IN UINTN Pages)39 AllocatePages (
40 IN UINTN Pages
41 )
42 {
43 EFI_PEI_HOB_POINTERS Hob;
44 EFI_PHYSICAL_ADDRESS Offset;
45
46 Hob.Raw = GetHobList ();
47
48 // Check to see if on 4k boundary
49 Offset = Hob.HandoffInformationTable->EfiFreeMemoryTop & 0xFFF;
50 if (Offset != 0) {
51 // If not aligned, make the allocation aligned.
52 Hob.HandoffInformationTable->EfiFreeMemoryTop -= Offset;
53 }
54
55 //
56 // Verify that there is sufficient memory to satisfy the allocation
57 //
58 if (Hob.HandoffInformationTable->EfiFreeMemoryTop - ((Pages * EFI_PAGE_SIZE) + sizeof (EFI_HOB_MEMORY_ALLOCATION)) < Hob.HandoffInformationTable->EfiFreeMemoryBottom) {
59 return 0;
60 } else {
61 //
62 // Update the PHIT to reflect the memory usage
63 //
64 Hob.HandoffInformationTable->EfiFreeMemoryTop -= Pages * EFI_PAGE_SIZE;
65
66 // This routine used to create a memory allocation HOB a la PEI, but that's not
67 // necessary for us.
68
69 //
70 // Create a memory allocation HOB.
71 //
72 BuildMemoryAllocationHob (
73 Hob.HandoffInformationTable->EfiFreeMemoryTop,
74 Pages * EFI_PAGE_SIZE,
75 EfiBootServicesData
76 );
77 return (VOID *)(UINTN)Hob.HandoffInformationTable->EfiFreeMemoryTop;
78 }
79 }
80
81
82 /**
83 Allocates one or more 4KB pages of type EfiBootServicesData at a specified alignment.
84
85 Allocates the number of 4KB pages specified by Pages of type EfiBootServicesData with an
86 alignment specified by Alignment. The allocated buffer is returned. If Pages is 0, then NULL is
87 returned. If there is not enough memory at the specified alignment remaining to satisfy the
88 request, then NULL is returned.
89 If Alignment is not a power of two and Alignment is not zero, then ASSERT().
90
91 @param Pages The number of 4 KB pages to allocate.
92 @param Alignment The requested alignment of the allocation. Must be a power of two.
93 If Alignment is zero, then byte alignment is used.
94
95 @return A pointer to the allocated buffer or NULL if allocation fails.
96
97 **/
98 VOID *
99 EFIAPI
AllocateAlignedPages(IN UINTN Pages,IN UINTN Alignment)100 AllocateAlignedPages (
101 IN UINTN Pages,
102 IN UINTN Alignment
103 )
104 {
105 VOID *Memory;
106 UINTN AlignmentMask;
107
108 //
109 // Alignment must be a power of two or zero.
110 //
111 ASSERT ((Alignment & (Alignment - 1)) == 0);
112
113 if (Pages == 0) {
114 return NULL;
115 }
116 //
117 // Make sure that Pages plus EFI_SIZE_TO_PAGES (Alignment) does not overflow.
118 //
119 ASSERT (Pages <= (MAX_ADDRESS - EFI_SIZE_TO_PAGES (Alignment)));
120 //
121 // We would rather waste some memory to save PEI code size.
122 //
123 Memory = (VOID *)(UINTN)AllocatePages (Pages + EFI_SIZE_TO_PAGES (Alignment));
124 if (Alignment == 0) {
125 AlignmentMask = Alignment;
126 } else {
127 AlignmentMask = Alignment - 1;
128 }
129 return (VOID *) (UINTN) (((UINTN) Memory + AlignmentMask) & ~AlignmentMask);
130 }
131
132
133 /**
134 Frees one or more 4KB pages that were previously allocated with one of the page allocation
135 functions in the Memory Allocation Library.
136
137 Frees the number of 4KB pages specified by Pages from the buffer specified by Buffer. Buffer
138 must have been allocated on a previous call to the page allocation services of the Memory
139 Allocation Library. If it is not possible to free allocated pages, then this function will
140 perform no actions.
141
142 If Buffer was not allocated with a page allocation function in the Memory Allocation Library,
143 then ASSERT().
144 If Pages is zero, then ASSERT().
145
146 @param Buffer Pointer to the buffer of pages to free.
147 @param Pages The number of 4 KB pages to free.
148
149 **/
150 VOID
151 EFIAPI
FreePages(IN VOID * Buffer,IN UINTN Pages)152 FreePages (
153 IN VOID *Buffer,
154 IN UINTN Pages
155 )
156 {
157 // For now, we do not support the ability to free pages in the PrePei Memory Allocator.
158 // The allocated memory is lost.
159 }
160
161 /**
162 Allocates a buffer of type EfiBootServicesData.
163
164 Allocates the number bytes specified by AllocationSize of type EfiBootServicesData and returns a
165 pointer to the allocated buffer. If AllocationSize is 0, then a valid buffer of 0 size is
166 returned. If there is not enough memory remaining to satisfy the request, then NULL is returned.
167
168 @param AllocationSize The number of bytes to allocate.
169
170 @return A pointer to the allocated buffer or NULL if allocation fails.
171
172 **/
173 VOID *
174 EFIAPI
AllocatePool(IN UINTN AllocationSize)175 AllocatePool (
176 IN UINTN AllocationSize
177 )
178 {
179 EFI_HOB_MEMORY_POOL *Hob;
180
181 Hob = GetHobList ();
182
183
184 //
185 // Verify that there is sufficient memory to satisfy the allocation
186 //
187 if (AllocationSize > 0x10000) {
188 // Please call AllcoatePages for big allocations
189 return 0;
190 } else {
191
192 Hob = (EFI_HOB_MEMORY_POOL *)CreateHob (EFI_HOB_TYPE_MEMORY_POOL, (UINT16)(sizeof (EFI_HOB_TYPE_MEMORY_POOL) + AllocationSize));
193 return (VOID *)(Hob + 1);
194 }
195 }
196
197 /**
198 Frees a buffer that was previously allocated with one of the pool allocation functions in the
199 Memory Allocation Library.
200
201 Frees the buffer specified by Buffer. Buffer must have been allocated on a previous call to the
202 pool allocation services of the Memory Allocation Library. If it is not possible to free pool
203 resources, then this function will perform no actions.
204
205 If Buffer was not allocated with a pool allocation function in the Memory Allocation Library,
206 then ASSERT().
207
208 @param Buffer Pointer to the buffer to free.
209
210 **/
211 VOID
212 EFIAPI
FreePool(IN VOID * Buffer)213 FreePool (
214 IN VOID *Buffer
215 )
216 {
217 // Not implemented yet
218 }
219