MdePkg/Include/Protocol/SmmPeriodicTimerDispatch2.h

   1 /** @file
   2   SMM Periodic Timer Dispatch Protocol as defined in PI 1.1 Specification
   3   Volume 4 System Management Mode Core Interface.
   4
   5   This protocol provides the parent dispatch service for the periodical timer SMI source generator.
   6
   7   Copyright (c) 2009, Intel Corporation
   8   All rights reserved. This program and the accompanying materials
   9   are licensed and made available under the terms and conditions of the BSD License
  10   which accompanies this distribution.  The full text of the license may be found at
  11   http://opensource.org/licenses/bsd-license.php
  12
  13   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  14   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  15
  16   @par Revision Reference:
  17   This protocol is from PI Version 1.1.
  18
  19 **/
  20
  21 #ifndef _SMM_PERIODIC_TIMER_DISPATCH2_H_
  22 #define _SMM_PERIODIC_TIMER_DISPATCH2_H_
  23
  24 #include <Pi/PiSmmCis.h>
  25
  26 ///
  27 /// Note:
  28 ///   To avoid name conflict between PI and Framework SMM spec, the following names defined
  29 ///   in PI 1.2 SMM spec are renamed. These renamings are not yet in a public PI spec and errta.
  30 ///
  31 ///   EFI_SMM_PERIODIC_TIMER_REGISTER   -> EFI_SMM_PERIODIC_TIMER_REGISTER2
  32 ///   EFI_SMM_PERIODIC_TIMER_UNREGISTER -> EFI_SMM_PERIODIC_TIMER_UNREGISTER2
  33 ///   EFI_SMM_PERIODIC_TIMER_INTERVAL   -> EFI_SMM_PERIODIC_TIMER_INTERVAL2
  34 ///
  35
  36 #define EFI_SMM_PERIODIC_TIMER_DISPATCH2_PROTOCOL_GUID \
  37   { \
  38     0x4cec368e, 0x8e8e, 0x4d71, {0x8b, 0xe1, 0x95, 0x8c, 0x45, 0xfc, 0x8a, 0x53 } \
  39   }
  40
  41 ///
  42 /// Example: A chipset supports periodic SMIs on every 64ms or 2 seconds.
  43 ///   A child wishes schedule a period SMI to fire on a period of 3 seconds, there
  44 ///   are several ways to approach the problem:
  45 ///   1. The child may accept a 4 second periodic rate, in which case it registers with
  46 ///        Period = 40000
  47 ///        SmiTickInterval = 20000
  48 ///      The resulting SMI will occur every 2 seconds with the child called back on
  49 ///      every 2nd SMI.
  50 ///      NOTE: the same result would occur if the child set SmiTickInterval = 0.
  51 ///   2. The child may choose the finer granularity SMI (64ms):
  52 ///        Period = 30000
  53 ///        SmiTickInterval = 640
  54 ///      The resulting SMI will occur every 64ms with the child called back on
  55 ///      every 47th SMI.
  56 ///      NOTE: the child driver should be aware that this will result in more
  57 ///        SMIs occuring during system runtime which can negatively impact system
  58 ///        performance.
  59 ///
  60 typedef struct {
  61   ///
  62   /// The minimum period of time in 100 nanosecond units that the child gets called. The
  63   /// child will be called back after a time greater than the time Period.
  64   ///
  65   UINT64  Period;
  66   ///
  67   /// The period of time interval between SMIs. Children of this interface should use this
  68   /// field when registering for periodic timer intervals when a finer granularity periodic
  69   /// SMI is desired.
  70   ///
  71   UINT64  SmiTickInterval;
  72 } EFI_SMM_PERIODIC_TIMER_REGISTER_CONTEXT;
  73
  74 ///
  75 /// The DispatchFunction will be called with Context set to the same value as was passed into
  76 /// Register() in RegisterContext and with CommBuffer pointing to an instance of
  77 /// EFI_SMM_PERIODIC_TIMER_CONTEXT and CommBufferSize pointing to its size.
  78 ///
  79 typedef struct {
  80   ///
  81   /// ElapsedTime is the actual time in 100 nanosecond units elapsed since last called, a
  82   /// value of 0 indicates an unknown amount of time.
  83   ///
  84   UINT64  ElapsedTime;
  85 } EFI_SMM_PERIODIC_TIMER_CONTEXT;
  86
  87 typedef struct _EFI_SMM_PERIODIC_TIMER_DISPATCH2_PROTOCOL  EFI_SMM_PERIODIC_TIMER_DISPATCH2_PROTOCOL;
  88
  89 /**
  90   Register a child SMI source dispatch function for SMM periodic timer.
  91
  92   This service registers a function (DispatchFunction) which will be called when at least the
  93   amount of time specified by RegisterContext has elapsed. On return, DispatchHandle
  94   contains a unique handle which may be used later to unregister the function using UnRegister().
  95   The DispatchFunction will be called with Context set to the same value as was passed into
  96   this function in RegisterContext and with CommBuffer pointing to an instance of
  97   EFI_SMM_PERIODIC_TIMER_CONTEXT and CommBufferSize pointing to its size.
  98
  99   @param[in]  This               Pointer to the EFI_SMM_PERIODIC_TIMER_DISPATCH2_PROTOCOL instance.
 100   @param[in]  DispatchFunction   Function to register for handler when at least the specified amount
 101                                  of time has elapsed.
 102   @param[in]  RegisterContext    Pointer to the dispatch function's context.
 103                                  The caller fills this context in before calling
 104                                  the register function to indicate to the register
 105                                  function the period at which the dispatch function
 106                                  should be invoked.
 107   @param[out] DispatchHandle     Handle generated by the dispatcher to track the function instance.
 108
 109   @retval EFI_SUCCESS            The dispatch function has been successfully
 110                                  registered and the SMI source has been enabled.
 111   @retval EFI_DEVICE_ERROR       The driver was unable to enable the SMI source.
 112   @retval EFI_INVALID_PARAMETER  RegisterContext is invalid. The period input value
 113                                  is not within valid range.
 114   @retval EFI_OUT_OF_RESOURCES   There is not enough memory (system or SMM) to manage this child.
 115 **/
 116 typedef
 117 EFI_STATUS
 118 (EFIAPI *EFI_SMM_PERIODIC_TIMER_REGISTER2)(
 119   IN CONST EFI_SMM_PERIODIC_TIMER_DISPATCH2_PROTOCOL  *This,
 120   IN       EFI_SMM_HANDLER_ENTRY_POINT2               DispatchFunction,
 121   IN CONST EFI_SMM_PERIODIC_TIMER_REGISTER_CONTEXT    *RegisterContext,
 122   OUT      EFI_HANDLE                                 *DispatchHandle
 123   );
 124
 125 /**
 126   Unregisters a periodic timer service.
 127
 128   This service removes the handler associated with DispatchHandle so that it will no longer be
 129   called when the time has elapsed.
 130
 131   @param[in] This                Pointer to the EFI_SMM_PERIODIC_TIMER_DISPATCH2_PROTOCOL instance.
 132   @param[in] DispatchHandle      Handle of the service to remove.
 133
 134   @retval EFI_SUCCESS            The service has been successfully removed.
 135   @retval EFI_INVALID_PARAMETER  The DispatchHandle was not valid.
 136 **/
 137 typedef
 138 EFI_STATUS
 139 (EFIAPI *EFI_SMM_PERIODIC_TIMER_UNREGISTER2)(
 140   IN CONST EFI_SMM_PERIODIC_TIMER_DISPATCH2_PROTOCOL  *This,
 141   IN       EFI_HANDLE                                 DispatchHandle
 142   );
 143
 144 /**
 145   Returns the next SMI tick period supported by the chipset.
 146
 147   The order returned is from longest to shortest interval period.
 148
 149   @param[in]     This             Pointer to the EFI_SMM_PERIODIC_TIMER_DISPATCH2_PROTOCOL instance.
 150   @param[in,out] SmiTickInterval  Pointer to pointer of next shorter SMI interval
 151                                   period supported by the child. This parameter works as a get-first,
 152                                   get-next field.The first time this function is called, *SmiTickInterval
 153                                   should be set to NULL to get the longest SMI interval.The returned
 154                                   *SmiTickInterval should be passed in on subsequent calls to get the
 155                                   next shorter interval period until *SmiTickInterval = NULL.
 156
 157   @retval EFI_SUCCESS             The service returned successfully.
 158 **/
 159 typedef
 160 EFI_STATUS
 161 (EFIAPI *EFI_SMM_PERIODIC_TIMER_INTERVAL2)(
 162   IN CONST EFI_SMM_PERIODIC_TIMER_DISPATCH2_PROTOCOL  *This,
 163   IN OUT UINT64                                       **SmiTickInterval
 164   );
 165
 166 ///
 167 /// Interface structure for the SMM Periodic Timer Dispatch Protocol
 168 ///
 169 /// This protocol provides the parent dispatch service for the periodical timer SMI source generator.
 170 ///
 171 struct _EFI_SMM_PERIODIC_TIMER_DISPATCH2_PROTOCOL {
 172   EFI_SMM_PERIODIC_TIMER_REGISTER2    Register;
 173   EFI_SMM_PERIODIC_TIMER_UNREGISTER2  UnRegister;
 174   EFI_SMM_PERIODIC_TIMER_INTERVAL2    GetNextShorterInterval;
 175 };
 176
 177 extern EFI_GUID gEfiSmmPeriodicTimerDispatch2ProtocolGuid;
 178
 179 #endif
 180