ReactOS  0.4.13-dev-247-g0f29b3f
time.c
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1 /*
2  * COPYRIGHT: See COPYING.ARM in the top level directory
3  * PROJECT: ReactOS UEFI Boot Library
4  * FILE: boot/environ/lib/platform/time.c
5  * PURPOSE: Boot Library Time Management Routines
6  * PROGRAMMER: Alex Ionescu (alex.ionescu@reactos.org)
7  */
8 
9 /* INCLUDES ******************************************************************/
10 
11 #include "bl.h"
12 
13 /* DATA VARIABLES ************************************************************/
14 
16 
17 /* FUNCTIONS *****************************************************************/
18 
21  VOID
22  )
23 {
24 #if defined(_M_IX86) || defined(_M_X64)
25  ULONG Count;
26  INT CpuInfo[4];
27  ULONGLONG TimeStamp1, TimeStamp2, Delta;
28 
29  /* Check if the ISVM bit it set, meaning we're in a hypervisor */
30  __cpuid(CpuInfo, 1);
31  Count = CpuInfo[2] & 0x80000000 ? 10 : 1;
32 
33  /* Loop trying to get an accurate TSC */
34  do
35  {
36  /* Stall for 1us and get count 1 */
37  EfiStall(1);
38  TimeStamp1 = __rdtsc();
39 
40  /* Stall for 1000us and get count 2*/
41  EfiStall(1000);
42  TimeStamp2 = __rdtsc();
43 
44  /* Stall for 9000us and get the difference */
45  EfiStall(9000);
46  Delta = __rdtsc() - TimeStamp2;
47 
48  /* Keep going as long as the TSC is fluctuating */
49  --Count;
50  } while (((TimeStamp2 - TimeStamp1) > Delta) && (Count));
51 
52  /* Set the frequency based on the two measurements we took */
53  BlpTimePerformanceFrequency = 125 * (Delta - (TimeStamp2 - TimeStamp1)) & 0x1FFFFFFFFFFFFFF;
54  return STATUS_SUCCESS;
55 #else
56  EfiPrintf(L"BlpTimeMeasureTscFrequency not implemented for this platform.\r\n");
58 #endif
59 }
60 
63  VOID
64  )
65 {
66 #if defined(_M_IX86) || defined(_M_X64)
67  INT CpuInfo[4];
68 
69  /* Check if the ISVM bit it set, meaning we're in a hypervisor */
70  __cpuid(CpuInfo, 1);
71  if (CpuInfo[2] & 0x80000000)
72  {
73  /* Get the Hypervisor Identification Leaf */
74  __cpuid(CpuInfo, 0x40000001);
75 
76  /* Is this Hyper-V? */
77  if (CpuInfo[0] == '1#vH')
78  {
79  /* Get the Hypervisor Feature Identification Leaf */
80  __cpuid(CpuInfo, 0x40000003);
81 
82  /* Check if HV_X64_MSR_REFERENCE_TSC is present */
83  if (CpuInfo[3] & 0x100)
84  {
85  /* Read the TSC frequency from the MSR */
87  return STATUS_SUCCESS;
88  }
89  }
90  }
91 
92  /* On other systems, compute it */
94 #else
95  EfiPrintf(L"BlpTimeCalibratePerformanceCounter not implemented for this platform.\r\n");
97 #endif
98 }
99 
100 ULONGLONG
103  )
104 {
105 #if defined(_M_IX86) || defined(_M_X64)
106  /* Check if caller wants frequency */
107  if (Frequency)
108  {
109  /* Return it */
111  }
112 
113  /* Return the TSC value */
114  return __rdtsc();
115 #else
116  EfiPrintf(L"BlTimeQueryPerformanceCounter not implemented for this platform.\r\n");
117  return 0;
118 #endif
119 };
NTSTATUS EfiStall(_In_ ULONG StallTime)
Definition: firmware.c:1003
ULONGLONG BlpTimePerformanceFrequency
Definition: time.c:15
#define STATUS_NOT_IMPLEMENTED
Definition: ntstatus.h:225
LONG NTSTATUS
Definition: precomp.h:26
PPC_QUAL unsigned long long __rdtsc(void)
Definition: intrin_ppc.h:688
_Inout_ __drv_aliasesMem PSLIST_ENTRY _Inout_ PSLIST_ENTRY _In_ ULONG Count
Definition: exfuncs.h:1015
NTSTATUS BlpTimeCalibratePerformanceCounter(VOID)
Definition: time.c:62
int32_t INT
Definition: typedefs.h:56
PPC_QUAL unsigned long long __readmsr()
Definition: intrin_ppc.h:741
#define _Out_opt_
Definition: no_sal2.h:339
NTSTATUS BlpTimeMeasureTscFrequency(VOID)
Definition: time.c:20
uint64_t ULONGLONG
Definition: typedefs.h:65
static const WCHAR L[]
Definition: oid.c:1250
PPC_QUAL void __cpuid(int CPUInfo[], const int InfoType)
Definition: intrin_ppc.h:682
static ULONG Delta
Definition: xboxvideo.c:28
VOID EfiPrintf(_In_ PWCHAR Format,...)
Definition: firmware.c:126
static LARGE_INTEGER Frequency
Definition: clock.c:41
unsigned int ULONG
Definition: retypes.h:1
ULONGLONG BlTimeQueryPerformanceCounter(_Out_opt_ PLARGE_INTEGER Frequency)
Definition: time.c:101
return STATUS_SUCCESS
Definition: btrfs.c:2745
LONGLONG QuadPart
Definition: typedefs.h:112