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878ddf1f | 1 | /** @file\r |
2 | Timer Library functions built upon local APIC on IA32/x64.\r | |
3 | \r | |
4 | @bug Should use PCD to retrieve all the constants including index of\r | |
5 | the IA32_APIC_BASE MSR, the offsets of InitialCount, CorrentCount\r | |
6 | and DivideConfiguration.\r | |
7 | \r | |
8 | Copyright (c) 2006, Intel Corporation<BR>\r | |
9 | All rights reserved. This program and the accompanying materials\r | |
10 | are licensed and made available under the terms and conditions of the BSD License\r | |
11 | which accompanies this distribution. The full text of the license may be found at\r | |
12 | http://opensource.org/licenses/bsd-license.php\r | |
13 | \r | |
14 | THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r | |
15 | WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r | |
16 | \r | |
17 | Module Name: x86TimerLib.c\r | |
18 | \r | |
19 | **/\r | |
20 | \r | |
ed384ef3 | 21 | //\r |
22 | // The following 2 arrays are used in calculating the frequency of local APIC\r | |
23 | // timer. Refer to IA-32 developers' manual for more details.\r | |
24 | //\r | |
25 | \r | |
26 | GLOBAL_REMOVE_IF_UNREFERENCED\r | |
27 | CONST UINT32 mTimerLibLocalApicFrequencies[] = {\r | |
28 | 100000000,\r | |
29 | 133000000,\r | |
30 | 200000000,\r | |
31 | 166000000\r | |
32 | };\r | |
33 | \r | |
34 | GLOBAL_REMOVE_IF_UNREFERENCED\r | |
35 | CONST UINT8 mTimerLibLocalApicDivisor[] = {\r | |
36 | 0x02, 0x04, 0x08, 0x10,\r | |
37 | 0x02, 0x04, 0x08, 0x10,\r | |
38 | 0x20, 0x40, 0x80, 0x01,\r | |
39 | 0x20, 0x40, 0x80, 0x01\r | |
40 | };\r | |
41 | \r | |
42 | /**\r | |
43 | Internal function to retrieve the base address of local APIC.\r | |
44 | \r | |
45 | Internal function to retrieve the base address of local APIC.\r | |
46 | \r | |
47 | @return The base address of local APIC\r | |
48 | \r | |
49 | **/\r | |
50 | STATIC\r | |
878ddf1f | 51 | UINTN\r |
ed384ef3 | 52 | InternalX86GetApicBase (\r |
53 | VOID\r | |
54 | )\r | |
55 | {\r | |
56 | return (UINTN)AsmMsrBitFieldRead64 (27, 12, 35) << 12;\r | |
57 | }\r | |
58 | \r | |
59 | /**\r | |
60 | Internal function to return the frequency of the local APIC timer.\r | |
61 | \r | |
62 | Internal function to return the frequency of the local APIC timer.\r | |
63 | \r | |
64 | @param ApicBase The base address of memory mapped registers of local APIC.\r | |
65 | \r | |
66 | @return The frequency of the timer in Hz.\r | |
67 | \r | |
68 | **/\r | |
69 | STATIC\r | |
70 | UINT32\r | |
71 | InternalX86GetTimerFrequency (\r | |
72 | IN UINTN ApicBase\r | |
73 | )\r | |
74 | {\r | |
75 | return\r | |
76 | mTimerLibLocalApicFrequencies[AsmMsrBitFieldRead32 (44, 16, 18)] /\r | |
77 | mTimerLibLocalApicDivisor[MmioBitFieldRead32 (ApicBase + 0x3e0, 0, 3)];\r | |
78 | }\r | |
79 | \r | |
80 | /**\r | |
81 | Internal function to read the current tick counter of local APIC.\r | |
82 | \r | |
83 | Internal function to read the current tick counter of local APIC.\r | |
84 | \r | |
85 | @param ApicBase The base address of memory mapped registers of local APIC.\r | |
86 | \r | |
87 | @return The tick counter read.\r | |
88 | \r | |
89 | **/\r | |
90 | STATIC\r | |
91 | INT32\r | |
92 | InternalX86GetTimerTick (\r | |
93 | IN UINTN ApicBase\r | |
878ddf1f | 94 | )\r |
95 | {\r | |
ed384ef3 | 96 | return MmioRead32 (ApicBase + 0x390);\r |
97 | }\r | |
98 | \r | |
99 | /**\r | |
100 | Stalls the CPU for at least the given number of ticks.\r | |
101 | \r | |
102 | Stalls the CPU for at least the given number of ticks. It's invoked by\r | |
103 | MicroSecondDelay() and NanoSecondDelay().\r | |
104 | \r | |
105 | @param ApicBase The base address of memory mapped registers of local APIC.\r | |
106 | @param Delay A period of time to delay in ticks.\r | |
107 | \r | |
108 | **/\r | |
109 | STATIC\r | |
110 | VOID\r | |
111 | InternalX86Delay (\r | |
112 | IN UINTN ApicBase,\r | |
113 | IN UINT32 Delay\r | |
114 | )\r | |
115 | {\r | |
116 | INT32 Ticks;\r | |
117 | \r | |
ed384ef3 | 118 | //\r |
119 | // The target timer count is calculated here\r | |
120 | //\r | |
121 | Ticks = InternalX86GetTimerTick (ApicBase) - Delay;\r | |
122 | \r | |
123 | //\r | |
124 | // Wait until time out\r | |
125 | // Delay > 2^31 could not be handled by this function\r | |
126 | // Timer wrap-arounds are handled correctly by this function\r | |
127 | //\r | |
128 | while (InternalX86GetTimerTick (ApicBase) - Ticks >= 0);\r | |
878ddf1f | 129 | }\r |
130 | \r | |
131 | /**\r | |
132 | Stalls the CPU for at least the given number of microseconds.\r | |
133 | \r | |
134 | Stalls the CPU for the number of microseconds specified by MicroSeconds.\r | |
135 | \r | |
136 | @param MicroSeconds The minimum number of microseconds to delay.\r | |
137 | \r | |
ed384ef3 | 138 | @return MicroSeconds\r |
878ddf1f | 139 | \r |
140 | **/\r | |
141 | UINTN\r | |
142 | EFIAPI\r | |
143 | MicroSecondDelay (\r | |
144 | IN UINTN MicroSeconds\r | |
145 | )\r | |
146 | {\r | |
ed384ef3 | 147 | UINTN ApicBase;\r |
148 | \r | |
149 | ApicBase = InternalX86GetApicBase ();\r | |
150 | InternalX86Delay (\r | |
151 | ApicBase,\r | |
152 | (UINT32)DivU64x32 (\r | |
153 | MultU64x64 (\r | |
154 | InternalX86GetTimerFrequency (ApicBase),\r | |
155 | MicroSeconds\r | |
156 | ),\r | |
157 | 1000000u\r | |
158 | )\r | |
159 | );\r | |
160 | return MicroSeconds;\r | |
878ddf1f | 161 | }\r |
162 | \r | |
163 | /**\r | |
164 | Stalls the CPU for at least the given number of nanoseconds.\r | |
165 | \r | |
166 | Stalls the CPU for the number of nanoseconds specified by NanoSeconds.\r | |
167 | \r | |
168 | @param NanoSeconds The minimum number of nanoseconds to delay.\r | |
169 | \r | |
ed384ef3 | 170 | @return NanoSeconds\r |
878ddf1f | 171 | \r |
172 | **/\r | |
173 | UINTN\r | |
174 | EFIAPI\r | |
175 | NanoSecondDelay (\r | |
176 | IN UINTN NanoSeconds\r | |
177 | )\r | |
178 | {\r | |
ed384ef3 | 179 | UINTN ApicBase;\r |
878ddf1f | 180 | \r |
ed384ef3 | 181 | ApicBase = InternalX86GetApicBase ();\r |
182 | InternalX86Delay (\r | |
183 | ApicBase,\r | |
184 | (UINT32)DivU64x32 (\r | |
185 | MultU64x64 (\r | |
186 | InternalX86GetTimerFrequency (ApicBase),\r | |
187 | NanoSeconds\r | |
188 | ),\r | |
189 | 1000000000u\r | |
190 | )\r | |
191 | );\r | |
192 | return NanoSeconds;\r | |
878ddf1f | 193 | }\r |
194 | \r | |
195 | /**\r | |
196 | Retrieves the current value of a 64-bit free running performance counter.\r | |
197 | \r | |
198 | Retrieves the current value of a 64-bit free running performance counter. The\r | |
199 | counter can either count up by 1 or count down by 1. If the physical\r | |
200 | performance counter counts by a larger increment, then the counter values\r | |
201 | must be translated. The properties of the counter can be retrieved from\r | |
202 | GetPerformanceCounterProperties().\r | |
203 | \r | |
204 | @return The current value of the free running performance counter.\r | |
205 | \r | |
206 | **/\r | |
207 | UINT64\r | |
208 | EFIAPI\r | |
209 | GetPerformanceCounter (\r | |
210 | VOID\r | |
211 | )\r | |
212 | {\r | |
34913f24 | 213 | return (UINT64)(UINT32)InternalX86GetTimerTick (InternalX86GetApicBase ());\r |
878ddf1f | 214 | }\r |
215 | \r | |
216 | /**\r | |
217 | Retrieves the 64-bit frequency in Hz and the range of performance counter\r | |
218 | values.\r | |
219 | \r | |
220 | If StartValue is not NULL, then the value that the performance counter starts\r | |
221 | with immediately after is it rolls over is returned in StartValue. If\r | |
222 | EndValue is not NULL, then the value that the performance counter end with\r | |
223 | immediately before it rolls over is returned in EndValue. The 64-bit\r | |
224 | frequency of the performance counter in Hz is always returned. If StartValue\r | |
225 | is less than EndValue, then the performance counter counts up. If StartValue\r | |
226 | is greater than EndValue, then the performance counter counts down. For\r | |
227 | example, a 64-bit free running counter that counts up would have a StartValue\r | |
228 | of 0 and an EndValue of 0xFFFFFFFFFFFFFFFF. A 24-bit free running counter\r | |
229 | that counts down would have a StartValue of 0xFFFFFF and an EndValue of 0.\r | |
230 | \r | |
231 | @param StartValue The value the performance counter starts with when it\r | |
232 | rolls over.\r | |
233 | @param EndValue The value that the performance counter ends with before\r | |
234 | it rolls over.\r | |
235 | \r | |
236 | @return The frequency in Hz.\r | |
237 | \r | |
238 | **/\r | |
239 | UINT64\r | |
240 | EFIAPI\r | |
241 | GetPerformanceCounterProperties (\r | |
5117b83b | 242 | OUT UINT64 *StartValue, OPTIONAL\r |
243 | OUT UINT64 *EndValue OPTIONAL\r | |
878ddf1f | 244 | )\r |
245 | {\r | |
878ddf1f | 246 | UINTN ApicBase;\r |
247 | \r | |
ed384ef3 | 248 | ApicBase = InternalX86GetApicBase ();\r |
878ddf1f | 249 | \r |
250 | if (StartValue != NULL) {\r | |
251 | *StartValue = MmioRead32 (ApicBase + 0x380);\r | |
252 | }\r | |
253 | \r | |
254 | if (EndValue != NULL) {\r | |
255 | *EndValue = 0;\r | |
256 | }\r | |
257 | \r | |
34913f24 | 258 | return (UINT64)InternalX86GetTimerFrequency (ApicBase);\r |
878ddf1f | 259 | }\r |