1 /** @file
2 GCC inline implementation of BaseSynchronizationLib processor specific functions.
3
4 Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR>
5 Portions copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
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
17
18
19 /**
20 Performs an atomic increment of an 32-bit unsigned integer.
21
22 Performs an atomic increment of the 32-bit unsigned integer specified by
23 Value and returns the incremented value. The increment operation must be
24 performed using MP safe mechanisms. The state of the return value is not
25 guaranteed to be MP safe.
26
27 @param Value A pointer to the 32-bit value to increment.
28
29 @return The incremented value.
30
31 **/
32 UINT32
33 EFIAPI
InternalSyncIncrement(IN volatile UINT32 * Value)34 InternalSyncIncrement (
35 IN volatile UINT32 *Value
36 )
37 {
38 UINT32 Result;
39
40 __asm__ __volatile__ (
41 "lock \n\t"
42 "incl %2 \n\t"
43 "mov %2, %%eax "
44 : "=a" (Result), // %0
45 "=m" (*Value) // %1
46 : "m" (*Value) // %2
47 : "memory",
48 "cc"
49 );
50
51 return Result;
52 }
53
54
55 /**
56 Performs an atomic decrement of an 32-bit unsigned integer.
57
58 Performs an atomic decrement of the 32-bit unsigned integer specified by
59 Value and returns the decremented value. The decrement operation must be
60 performed using MP safe mechanisms. The state of the return value is not
61 guaranteed to be MP safe.
62
63 @param Value A pointer to the 32-bit value to decrement.
64
65 @return The decremented value.
66
67 **/
68 UINT32
69 EFIAPI
InternalSyncDecrement(IN volatile UINT32 * Value)70 InternalSyncDecrement (
71 IN volatile UINT32 *Value
72 )
73 {
74 UINT32 Result;
75
76 __asm__ __volatile__ (
77 "lock \n\t"
78 "decl %2 \n\t"
79 "mov %2, %%eax "
80 : "=a" (Result), // %0
81 "=m" (*Value) // %1
82 : "m" (*Value) // %2
83 : "memory",
84 "cc"
85 );
86
87 return Result;
88 }
89
90
91 /**
92 Performs an atomic compare exchange operation on a 16-bit unsigned integer.
93
94 Performs an atomic compare exchange operation on the 16-bit unsigned integer
95 specified by Value. If Value is equal to CompareValue, then Value is set to
96 ExchangeValue and CompareValue is returned. If Value is not equal to CompareValue,
97 then Value is returned. The compare exchange operation must be performed using
98 MP safe mechanisms.
99
100
101 @param Value A pointer to the 16-bit value for the compare exchange
102 operation.
103 @param CompareValue 16-bit value used in compare operation.
104 @param ExchangeValue 16-bit value used in exchange operation.
105
106 @return The original *Value before exchange.
107
108 **/
109 UINT16
110 EFIAPI
InternalSyncCompareExchange16(IN OUT volatile UINT16 * Value,IN UINT16 CompareValue,IN UINT16 ExchangeValue)111 InternalSyncCompareExchange16 (
112 IN OUT volatile UINT16 *Value,
113 IN UINT16 CompareValue,
114 IN UINT16 ExchangeValue
115 )
116 {
117
118
119 __asm__ __volatile__ (
120 "lock \n\t"
121 "cmpxchgw %3, %1 "
122 : "=a" (CompareValue),
123 "=m" (*Value)
124 : "a" (CompareValue),
125 "r" (ExchangeValue),
126 "m" (*Value)
127 : "memory",
128 "cc"
129 );
130
131 return CompareValue;
132 }
133
134
135 /**
136 Performs an atomic compare exchange operation on a 32-bit unsigned integer.
137
138 Performs an atomic compare exchange operation on the 32-bit unsigned integer
139 specified by Value. If Value is equal to CompareValue, then Value is set to
140 ExchangeValue and CompareValue is returned. If Value is not equal to CompareValue,
141 then Value is returned. The compare exchange operation must be performed using
142 MP safe mechanisms.
143
144
145 @param Value A pointer to the 32-bit value for the compare exchange
146 operation.
147 @param CompareValue 32-bit value used in compare operation.
148 @param ExchangeValue 32-bit value used in exchange operation.
149
150 @return The original *Value before exchange.
151
152 **/
153 UINT32
154 EFIAPI
InternalSyncCompareExchange32(IN OUT volatile UINT32 * Value,IN UINT32 CompareValue,IN UINT32 ExchangeValue)155 InternalSyncCompareExchange32 (
156 IN OUT volatile UINT32 *Value,
157 IN UINT32 CompareValue,
158 IN UINT32 ExchangeValue
159 )
160 {
161
162
163 __asm__ __volatile__ (
164 "lock \n\t"
165 "cmpxchgl %3, %1 "
166 : "=a" (CompareValue), // %0
167 "=m" (*Value) // %1
168 : "a" (CompareValue), // %2
169 "r" (ExchangeValue), // %3
170 "m" (*Value)
171 : "memory",
172 "cc"
173 );
174
175 return CompareValue;
176 }
177
178
179 /**
180 Performs an atomic compare exchange operation on a 64-bit unsigned integer.
181
182 Performs an atomic compare exchange operation on the 64-bit unsigned integer specified
183 by Value. If Value is equal to CompareValue, then Value is set to ExchangeValue and
184 CompareValue is returned. If Value is not equal to CompareValue, then Value is returned.
185 The compare exchange operation must be performed using MP safe mechanisms.
186
187
188 @param Value A pointer to the 64-bit value for the compare exchange
189 operation.
190 @param CompareValue 64-bit value used in compare operation.
191 @param ExchangeValue 64-bit value used in exchange operation.
192
193 @return The original *Value before exchange.
194
195 **/
196 UINT64
197 EFIAPI
InternalSyncCompareExchange64(IN OUT volatile UINT64 * Value,IN UINT64 CompareValue,IN UINT64 ExchangeValue)198 InternalSyncCompareExchange64 (
199 IN OUT volatile UINT64 *Value,
200 IN UINT64 CompareValue,
201 IN UINT64 ExchangeValue
202 )
203 {
204
205 __asm__ __volatile__ (
206 "lock \n\t"
207 "cmpxchgq %3, %1 "
208 : "=a" (CompareValue), // %0
209 "=m" (*Value) // %1
210 : "a" (CompareValue), // %2
211 "r" (ExchangeValue), // %3
212 "m" (*Value)
213 : "memory",
214 "cc"
215 );
216
217 return CompareValue;
218 }
219
220
221