MdePkg/Include/Protocol/MmPeriodicTimerDispatch.h

   1 /** @file
   2   MM Periodic Timer Dispatch Protocol as defined in PI 1.5 Specification
   3   Volume 4 Management Mode Core Interface.
   4
   5   This protocol provides the parent dispatch service for the periodical timer MMI source generator.
   6
   7   Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
   8   SPDX-License-Identifier: BSD-2-Clause-Patent
   9
  10   @par Revision Reference:
  11   This protocol is from PI Version 1.5.
  12
  13 **/
  14
  15 #ifndef _MM_PERIODIC_TIMER_DISPATCH_H_
  16 #define _MM_PERIODIC_TIMER_DISPATCH_H_
  17
  18 #include <Pi/PiMmCis.h>
  19
  20 #define EFI_MM_PERIODIC_TIMER_DISPATCH_PROTOCOL_GUID \
  21   { \
  22     0x4cec368e, 0x8e8e, 0x4d71, {0x8b, 0xe1, 0x95, 0x8c, 0x45, 0xfc, 0x8a, 0x53 } \
  23   }
  24
  25 ///
  26 /// Example: A chipset supports periodic MMIs on every 64ms or 2 seconds.
  27 ///   A child wishes schedule a period MMI to fire on a period of 3 seconds, there
  28 ///   are several ways to approach the problem:
  29 ///   1. The child may accept a 4 second periodic rate, in which case it registers with
  30 ///        Period = 40000
  31 ///        MmiTickInterval = 20000
  32 ///      The resulting MMI will occur every 2 seconds with the child called back on
  33 ///      every 2nd MMI.
  34 ///      NOTE: the same result would occur if the child set MmiTickInterval = 0.
  35 ///   2. The child may choose the finer granularity MMI (64ms):
  36 ///        Period = 30000
  37 ///        MmiTickInterval = 640
  38 ///      The resulting MMI will occur every 64ms with the child called back on
  39 ///      every 47th MMI.
  40 ///      NOTE: the child driver should be aware that this will result in more
  41 ///        MMIs occuring during system runtime which can negatively impact system
  42 ///        performance.
  43 ///
  44 typedef struct {
  45   ///
  46   /// The minimum period of time in 100 nanosecond units that the child gets called. The
  47   /// child will be called back after a time greater than the time Period.
  48   ///
  49   UINT64  Period;
  50   ///
  51   /// The period of time interval between MMIs. Children of this interface should use this
  52   /// field when registering for periodic timer intervals when a finer granularity periodic
  53   /// MMI is desired.
  54   ///
  55   UINT64  MmiTickInterval;
  56 } EFI_MM_PERIODIC_TIMER_REGISTER_CONTEXT;
  57
  58 ///
  59 /// The DispatchFunction will be called with Context set to the same value as was passed into
  60 /// Register() in RegisterContext and with CommBuffer pointing to an instance of
  61 /// EFI_MM_PERIODIC_TIMER_CONTEXT and CommBufferSize pointing to its size.
  62 ///
  63 typedef struct {
  64   ///
  65   /// ElapsedTime is the actual time in 100 nanosecond units elapsed since last called, a
  66   /// value of 0 indicates an unknown amount of time.
  67   ///
  68   UINT64  ElapsedTime;
  69 } EFI_MM_PERIODIC_TIMER_CONTEXT;
  70
  71 typedef struct _EFI_MM_PERIODIC_TIMER_DISPATCH_PROTOCOL  EFI_MM_PERIODIC_TIMER_DISPATCH_PROTOCOL;
  72
  73 /**
  74   Register a child MMI source dispatch function for MM periodic timer.
  75
  76   This service registers a function (DispatchFunction) which will be called when at least the
  77   amount of time specified by RegisterContext has elapsed. On return, DispatchHandle
  78   contains a unique handle which may be used later to unregister the function using UnRegister().
  79   The DispatchFunction will be called with Context set to the same value as was passed into
  80   this function in RegisterContext and with CommBuffer pointing to an instance of
  81   EFI_MM_PERIODIC_TIMER_CONTEXT and CommBufferSize pointing to its size.
  82
  83   @param[in]  This               Pointer to the EFI_MM_PERIODIC_TIMER_DISPATCH_PROTOCOL instance.
  84   @param[in]  DispatchFunction   Function to register for handler when at least the specified amount
  85                                  of time has elapsed.
  86   @param[in]  RegisterContext    Pointer to the dispatch function's context.
  87                                  The caller fills this context in before calling
  88                                  the register function to indicate to the register
  89                                  function the period at which the dispatch function
  90                                  should be invoked.
  91   @param[out] DispatchHandle     Handle generated by the dispatcher to track the function instance.
  92
  93   @retval EFI_SUCCESS            The dispatch function has been successfully
  94                                  registered and the MMI source has been enabled.
  95   @retval EFI_DEVICE_ERROR       The driver was unable to enable the MMI source.
  96   @retval EFI_INVALID_PARAMETER  RegisterContext is invalid. The period input value
  97                                  is not within valid range.
  98   @retval EFI_OUT_OF_RESOURCES   There is not enough memory (system or MM) to manage this child.
  99 **/
 100 typedef
 101 EFI_STATUS
 102 (EFIAPI *EFI_MM_PERIODIC_TIMER_REGISTER)(
 103   IN CONST EFI_MM_PERIODIC_TIMER_DISPATCH_PROTOCOL    *This,
 104   IN       EFI_MM_HANDLER_ENTRY_POINT                 DispatchFunction,
 105   IN CONST EFI_MM_PERIODIC_TIMER_REGISTER_CONTEXT     *RegisterContext,
 106   OUT      EFI_HANDLE                                 *DispatchHandle
 107   );
 108
 109 /**
 110   Unregisters a periodic timer service.
 111
 112   This service removes the handler associated with DispatchHandle so that it will no longer be
 113   called when the time has elapsed.
 114
 115   @param[in] This                Pointer to the EFI_MM_PERIODIC_TIMER_DISPATCH_PROTOCOL instance.
 116   @param[in] DispatchHandle      Handle of the service to remove.
 117
 118   @retval EFI_SUCCESS            The service has been successfully removed.
 119   @retval EFI_INVALID_PARAMETER  The DispatchHandle was not valid.
 120 **/
 121 typedef
 122 EFI_STATUS
 123 (EFIAPI *EFI_MM_PERIODIC_TIMER_UNREGISTER)(
 124   IN CONST EFI_MM_PERIODIC_TIMER_DISPATCH_PROTOCOL  *This,
 125   IN       EFI_HANDLE                               DispatchHandle
 126   );
 127
 128 /**
 129   Returns the next MMI tick period supported by the chipset.
 130
 131   The order returned is from longest to shortest interval period.
 132
 133   @param[in]     This             Pointer to the EFI_MM_PERIODIC_TIMER_DISPATCH_PROTOCOL instance.
 134   @param[in,out] MmiTickInterval  Pointer to pointer of next shorter MMI interval
 135                                   period supported by the child. This parameter works as a get-first,
 136                                   get-next field.The first time this function is called, *MmiTickInterval
 137                                   should be set to NULL to get the longest MMI interval.The returned
 138                                   *MmiTickInterval should be passed in on subsequent calls to get the
 139                                   next shorter interval period until *MmiTickInterval = NULL.
 140
 141   @retval EFI_SUCCESS             The service returned successfully.
 142 **/
 143 typedef
 144 EFI_STATUS
 145 (EFIAPI *EFI_MM_PERIODIC_TIMER_INTERVAL)(
 146   IN CONST EFI_MM_PERIODIC_TIMER_DISPATCH_PROTOCOL  *This,
 147   IN OUT UINT64                                     **MmiTickInterval
 148   );
 149
 150 ///
 151 /// Interface structure for the MM Periodic Timer Dispatch Protocol
 152 ///
 153 /// This protocol provides the parent dispatch service for the periodical timer MMI source generator.
 154 ///
 155 struct _EFI_MM_PERIODIC_TIMER_DISPATCH_PROTOCOL {
 156   EFI_MM_PERIODIC_TIMER_REGISTER    Register;
 157   EFI_MM_PERIODIC_TIMER_UNREGISTER  UnRegister;
 158   EFI_MM_PERIODIC_TIMER_INTERVAL    GetNextShorterInterval;
 159 };
 160
 161 extern EFI_GUID gEfiMmPeriodicTimerDispatchProtocolGuid;
 162
 163 #endif
 164