hal/halppc/generic/timer.c

   1 /*
   2  * PROJECT:         ReactOS HAL
   3  * LICENSE:         GPL - See COPYING in the top level directory
   4  * FILE:            hal/halppc/generic/timer.c
   5  * PURPOSE:         HAL Timer Routines
   6  * PROGRAMMERS:     Alex Ionescu (alex.ionescu@reactos.org)
   7  */
   8
   9 /* INCLUDES ******************************************************************/
  10
  11 #include <hal.h>
  12 #define NDEBUG
  13 #include <debug.h>
  14
  15 /* GLOBALS *******************************************************************/
  16
  17 BOOLEAN HalpClockSetMSRate;
  18 ULONG HalpCurrentTimeIncrement;
  19 ULONG HalpCurrentRollOver;
  20 ULONG HalpNextMSRate = 14;
  21 ULONG HalpLargestClockMS = 15;
  22
  23 LARGE_INTEGER HalpRolloverTable[15] =
  24 {
  25     {{1197, 10032}},
  26     {{2394, 20064}},
  27     {{3591, 30096}},
  28     {{4767, 39952}},
  29     {{5964, 49984}},
  30     {{7161, 60016}},
  31     {{8358, 70048}},
  32     {{9555, 80080}},
  33     {{10731, 89936}},
  34     {{11949, 100144}},
  35     {{13125, 110000}},
  36     {{14322, 120032}},
  37     {{15519, 130064}},
  38     {{16695, 139920}},
  39     {{17892, 149952}}
  40 };
  41
  42 /* PRIVATE FUNCTIONS *********************************************************/
  43
  44 VOID
  45 NTAPI
  46 HalpInitializeClock(VOID)
  47 {
  48     //PKPRCB Prcb = KeGetCurrentPrcb();
  49     ULONG Increment;
  50     USHORT RollOver;
  51     ULONG Flags = 0;
  52
  53     /* Get increment and rollover for the largest time clock ms possible */
  54     Increment = HalpRolloverTable[HalpLargestClockMS - 1].HighPart;
  55     RollOver = (USHORT)HalpRolloverTable[HalpLargestClockMS - 1].LowPart;
  56
  57     /* Set the maximum and minimum increment with the kernel */
  58     HalpCurrentTimeIncrement = Increment;
  59     KeSetTimeIncrement(Increment, HalpRolloverTable[0].HighPart);
  60
  61     /* Disable interrupts */
  62     Flags = __readmsr();
  63     _disable();
  64
  65     /* Set the rollover */
  66     __outbyte(TIMER_CONTROL_PORT, TIMER_SC0 | TIMER_BOTH | TIMER_MD2);
  67     __outbyte(TIMER_DATA_PORT0, RollOver & 0xFF);
  68     __outbyte(TIMER_DATA_PORT0, RollOver >> 8);
  69
  70     /* Restore interrupts if they were previously enabled */
  71     __writemsr(Flags);
  72
  73     /* Save rollover and return */
  74     HalpCurrentRollOver = RollOver;
  75 }
  76
  77 /* PUBLIC FUNCTIONS ***********************************************************/
  78
  79 /*
  80  * @implemented
  81  */
  82 VOID
  83 NTAPI
  84 HalCalibratePerformanceCounter(IN volatile PLONG Count,
  85                                IN ULONGLONG NewCount)
  86 {
  87     ULONG Flags = 0;
  88
  89     /* Disable interrupts */
  90     Flags = __readmsr();
  91     _disable();
  92
  93     /* Do a decrement for this CPU */
  94     _InterlockedDecrement(Count);
  95
  96     /* Wait for other CPUs */
  97     while (*Count);
  98
  99     /* Restore interrupts if they were previously enabled */
 100     __writemsr(Flags);
 101 }
 102
 103 /*
 104  * @implemented
 105  */
 106 ULONG
 107 NTAPI
 108 HalSetTimeIncrement(IN ULONG Increment)
 109 {
 110     /* Round increment to ms */
 111     Increment /= 10000;
 112
 113     /* Normalize between our minimum (1 ms) and maximum (variable) setting */
 114     if (Increment > HalpLargestClockMS) Increment = HalpLargestClockMS;
 115     if (Increment <= 0) Increment = 1;
 116
 117     /* Set the rate and tell HAL we want to change it */
 118     HalpNextMSRate = Increment;
 119     HalpClockSetMSRate = TRUE;
 120
 121     /* Return the increment */
 122     return HalpRolloverTable[Increment - 1].HighPart;
 123 }
 124
 125 VOID
 126 NTHALAPI
 127 KeStallExecutionProcessor(ULONG USec)
 128 {
 129     LARGE_INTEGER Freq, Start = KeQueryPerformanceCounter(&Freq), End;
 130     LARGE_INTEGER Timebase, Remainder;
 131     Timebase.QuadPart = 1000000;
 132     Freq.QuadPart *= USec;
 133     End = RtlLargeIntegerDivide(Freq, Timebase, &Remainder);
 134     End.QuadPart += Start.QuadPart;
 135     while(End.QuadPart > __rdtsc());
 136 }
 137
 138 /* EOF */