Vlv2TbltDevicePkg/Library/IntelPchAcpiTimerLib/IntelPchAcpiTimerLib.c

   1 /** @file
   2   ICH9 ACPI Timer implements one instance of Timer Library.
   3
   4 Copyright (c) 2007 - 2014, Intel Corporation. All rights reserved.<BR>
   5
   6   SPDX-License-Identifier: BSD-2-Clause-Patent
   7
   8
   9
  10 **/
  11
  12 #include "CommonHeader.h"
  13
  14 /**
  15   The constructor function enables ACPI IO space.
  16
  17   If ACPI I/O space not enabled, this function will enable it.
  18   It will always return RETURN_SUCCESS.
  19
  20   @retval EFI_SUCCESS   The constructor always returns RETURN_SUCCESS.
  21
  22 **/
  23 RETURN_STATUS
  24 EFIAPI
  25 IntelPchAcpiTimerLibConstructor (
  26   VOID
  27   )
  28 {
  29   if ((PchLpcPciCfg8(R_PCH_LPC_ACPI_BASE) & B_PCH_LPC_ACPI_BASE_EN) == 0) {
  30   //
  31   // If ACPI I/O space is not enabled, program ACPI I/O base address and enable it.
  32   //
  33     MmioWrite16 (
  34       MmPciAddress (
  35         0,
  36         DEFAULT_PCI_BUS_NUMBER_PCH,
  37         PCI_DEVICE_NUMBER_PCH_LPC,
  38         PCI_FUNCTION_NUMBER_PCH_LPC,
  39         R_PCH_LPC_ACPI_BASE
  40         ),
  41       ((PcdGet16 (PcdPchAcpiIoPortBaseAddress) & B_PCH_LPC_ACPI_BASE_BAR) | B_PCH_LPC_ACPI_BASE_EN)
  42     );
  43   }
  44   return RETURN_SUCCESS;
  45 }
  46
  47 /**
  48   Internal function to read the current tick counter of ACPI.
  49
  50   Internal function to read the current tick counter of ACPI.
  51
  52   @return The tick counter read.
  53
  54 **/
  55 STATIC
  56 UINT32
  57 InternalAcpiGetTimerTick (
  58   VOID
  59   )
  60 {
  61   return IoRead32 (PcdGet16 (PcdPchAcpiIoPortBaseAddress) + R_PCH_ACPI_PM1_TMR);
  62 }
  63
  64 /**
  65   Stalls the CPU for at least the given number of ticks.
  66
  67   Stalls the CPU for at least the given number of ticks. It's invoked by
  68   MicroSecondDelay() and NanoSecondDelay().
  69
  70   @param  Delay     A period of time to delay in ticks.
  71
  72 **/
  73 STATIC
  74 VOID
  75 InternalAcpiDelay (
  76   IN      UINT32                    Delay
  77   )
  78 {
  79   UINT32                            Ticks;
  80   UINT32                            Times;
  81
  82   Times    = Delay >> 22;
  83   Delay   &= BIT22 - 1;
  84   do {
  85     //
  86     // The target timer count is calculated here
  87     //
  88     Ticks    = InternalAcpiGetTimerTick () + Delay;
  89     Delay    = BIT22;
  90     //
  91     // Wait until time out
  92     // Delay >= 2^23 could not be handled by this function
  93     // Timer wrap-arounds are handled correctly by this function
  94     //
  95     while (((Ticks - InternalAcpiGetTimerTick ()) & BIT23) == 0) {
  96       CpuPause ();
  97     }
  98   } while (Times-- > 0);
  99 }
 100
 101 /**
 102   Stalls the CPU for at least the given number of microseconds.
 103
 104   Stalls the CPU for the number of microseconds specified by MicroSeconds.
 105
 106   @param  MicroSeconds  The minimum number of microseconds to delay.
 107
 108   @return MicroSeconds
 109
 110 **/
 111 UINTN
 112 EFIAPI
 113 MicroSecondDelay (
 114   IN      UINTN                     MicroSeconds
 115   )
 116 {
 117   InternalAcpiDelay (
 118     (UINT32)DivU64x32 (
 119               MultU64x32 (
 120                 MicroSeconds,
 121                 V_PCH_ACPI_PM1_TMR_FREQUENCY
 122                 ),
 123               1000000u
 124               )
 125     );
 126   return MicroSeconds;
 127 }
 128
 129 /**
 130   Stalls the CPU for at least the given number of nanoseconds.
 131
 132   Stalls the CPU for the number of nanoseconds specified by NanoSeconds.
 133
 134   @param  NanoSeconds The minimum number of nanoseconds to delay.
 135
 136   @return NanoSeconds
 137
 138 **/
 139 UINTN
 140 EFIAPI
 141 NanoSecondDelay (
 142   IN      UINTN                     NanoSeconds
 143   )
 144 {
 145   InternalAcpiDelay (
 146     (UINT32)DivU64x32 (
 147               MultU64x32 (
 148                 NanoSeconds,
 149                 V_PCH_ACPI_PM1_TMR_FREQUENCY
 150                 ),
 151               1000000000u
 152               )
 153     );
 154   return NanoSeconds;
 155 }
 156
 157 /**
 158   Retrieves the current value of a 64-bit free running performance counter.
 159
 160   Retrieves the current value of a 64-bit free running performance counter. The
 161   counter can either count up by 1 or count down by 1. If the physical
 162   performance counter counts by a larger increment, then the counter values
 163   must be translated. The properties of the counter can be retrieved from
 164   GetPerformanceCounterProperties().
 165
 166   @return The current value of the free running performance counter.
 167
 168 **/
 169 UINT64
 170 EFIAPI
 171 GetPerformanceCounter (
 172   VOID
 173   )
 174 {
 175   return (UINT64)InternalAcpiGetTimerTick ();
 176 }
 177
 178 /**
 179   Retrieves the 64-bit frequency in Hz and the range of performance counter
 180   values.
 181
 182   If StartValue is not NULL, then the value that the performance counter starts
 183   with immediately after is it rolls over is returned in StartValue. If
 184   EndValue is not NULL, then the value that the performance counter end with
 185   immediately before it rolls over is returned in EndValue. The 64-bit
 186   frequency of the performance counter in Hz is always returned. If StartValue
 187   is less than EndValue, then the performance counter counts up. If StartValue
 188   is greater than EndValue, then the performance counter counts down. For
 189   example, a 64-bit free running counter that counts up would have a StartValue
 190   of 0 and an EndValue of 0xFFFFFFFFFFFFFFFF. A 24-bit free running counter
 191   that counts down would have a StartValue of 0xFFFFFF and an EndValue of 0.
 192
 193   @param  StartValue  The value the performance counter starts with when it
 194                       rolls over.
 195   @param  EndValue    The value that the performance counter ends with before
 196                       it rolls over.
 197
 198   @return             The frequency in Hz.
 199
 200 **/
 201 UINT64
 202 EFIAPI
 203 GetPerformanceCounterProperties (
 204   OUT      UINT64                    *StartValue,  OPTIONAL
 205   OUT      UINT64                    *EndValue     OPTIONAL
 206   )
 207 {
 208   if (StartValue != NULL) {
 209     *StartValue = 0;
 210   }
 211
 212   if (EndValue != NULL) {
 213     *EndValue = V_PCH_ACPI_PM1_TMR_MAX_VAL - 1;
 214   }
 215
 216   return V_PCH_ACPI_PM1_TMR_FREQUENCY;
 217 }
 218
 219 /**
 220   Converts elapsed ticks of performance counter to time in nanoseconds.
 221
 222   This function converts the elapsed ticks of running performance counter to
 223   time value in unit of nanoseconds.
 224
 225   @param  Ticks     The number of elapsed ticks of running performance counter.
 226
 227   @return           The elapsed time in nanoseconds.
 228
 229 **/
 230 UINT64
 231 EFIAPI
 232 GetTimeInNanoSecond (
 233   IN      UINT64                     Ticks
 234   )
 235 {
 236   UINT64  NanoSeconds;
 237   UINT32  Remainder;
 238
 239   //
 240   //          Ticks
 241   // Time = --------- x 1,000,000,000
 242   //        Frequency
 243   //
 244   NanoSeconds = MultU64x32 (DivU64x32Remainder (Ticks, V_PCH_ACPI_PM1_TMR_FREQUENCY, &Remainder), 1000000000u);
 245
 246   //
 247   // Frequency < 0x100000000, so Remainder < 0x100000000, then (Remainder * 1,000,000,000)
 248   // will not overflow 64-bit.
 249   //
 250   NanoSeconds += DivU64x32 (MultU64x32 ((UINT64) Remainder, 1000000000u), V_PCH_ACPI_PM1_TMR_FREQUENCY);
 251
 252   return NanoSeconds;
 253 }
 254
 255