ArmPkg/Drivers/ArmScmiDxe/ScmiDxe.c

   1 /** @file
   2
   3   Copyright (c) 2017-2018, Arm Limited. All rights reserved.
   4
   5   This program and the accompanying materials
   6   are licensed and made available under the terms and conditions of the BSD License
   7   which accompanies this distribution.  The full text of the license may be found at
   8   http://opensource.org/licenses/bsd-license.php
   9
  10   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13   System Control and Management Interface V1.0
  14     http://infocenter.arm.com/help/topic/com.arm.doc.den0056a/
  15     DEN0056A_System_Control_and_Management_Interface.pdf
  16 **/
  17
  18 #include <Base.h>
  19 #include <Library/DebugLib.h>
  20 #include <Library/MemoryAllocationLib.h>
  21 #include <Library/UefiBootServicesTableLib.h>
  22 #include <Protocol/ArmScmiBaseProtocol.h>
  23 #include <Protocol/ArmScmiClockProtocol.h>
  24 #include <Protocol/ArmScmiPerformanceProtocol.h>
  25
  26 #include "ArmScmiBaseProtocolPrivate.h"
  27 #include "ArmScmiClockProtocolPrivate.h"
  28 #include "ArmScmiPerformanceProtocolPrivate.h"
  29 #include "ScmiDxe.h"
  30 #include "ScmiPrivate.h"
  31
  32 STATIC CONST SCMI_PROTOCOL_INIT_TABLE ProtocolInitFxns[MAX_PROTOCOLS] = {
  33   { ScmiBaseProtocolInit },
  34   { NULL },
  35   { NULL },
  36   { ScmiPerformanceProtocolInit },
  37   { ScmiClockProtocolInit },
  38   { NULL }
  39 };
  40
  41 /** ARM SCMI driver entry point function.
  42
  43   This function installs the SCMI Base protocol and a list of other
  44   protocols is queried using the Base protocol. If protocol is supported,
  45   driver will call each protocol init function to install the protocol on
  46   the ImageHandle.
  47
  48   @param[in] ImageHandle     Handle to this EFI Image which will be used to
  49                              install Base, Clock and Performance protocols.
  50   @param[in] SystemTable     A pointer to boot time system table.
  51
  52   @retval EFI_SUCCESS       Driver initalized successfully.
  53   @retval EFI_UNSUPPORTED   If SCMI base protocol version is not supported.
  54   @retval !(EFI_SUCCESS)    Other errors.
  55 **/
  56 EFI_STATUS
  57 EFIAPI
  58 ArmScmiDxeEntryPoint (
  59   IN EFI_HANDLE             ImageHandle,
  60   IN EFI_SYSTEM_TABLE       *SystemTable
  61   )
  62 {
  63   EFI_STATUS          Status;
  64   SCMI_BASE_PROTOCOL  *BaseProtocol;
  65   UINT32              Version;
  66   UINT32              Index;
  67   UINT32              NumProtocols;
  68   UINT32              ProtocolNo;
  69   UINT8               SupportedList[MAX_PROTOCOLS];
  70   UINT32              SupportedListSize = sizeof (SupportedList);
  71
  72   ProtocolNo = SCMI_PROTOCOL_ID_BASE & PROTOCOL_ID_MASK;
  73
  74   // Every SCMI implementation must implement the base protocol.
  75   Status = ProtocolInitFxns[ProtocolNo].Init (&ImageHandle);
  76   if (EFI_ERROR (Status)) {
  77     ASSERT (FALSE);
  78     return Status;
  79   }
  80
  81   Status = gBS->LocateProtocol (
  82                   &gArmScmiBaseProtocolGuid,
  83                   NULL,
  84                   (VOID**)&BaseProtocol
  85                   );
  86   if (EFI_ERROR (Status)) {
  87     ASSERT (FALSE);
  88     return Status;
  89   }
  90
  91   // Get SCMI Base protocol version.
  92   Status = BaseProtocol->GetVersion (BaseProtocol, &Version);
  93   if (EFI_ERROR (Status)) {
  94     ASSERT (FALSE);
  95     return Status;
  96   }
  97
  98   if (Version != BASE_PROTOCOL_VERSION) {
  99     ASSERT (FALSE);
 100     return EFI_UNSUPPORTED;
 101   }
 102
 103   // Apart from Base protocol, SCMI may implement various other protocols,
 104   // query total protocols implemented by the SCP firmware.
 105   NumProtocols = 0;
 106   Status = BaseProtocol->GetTotalProtocols (BaseProtocol, &NumProtocols);
 107   if (EFI_ERROR (Status)) {
 108     ASSERT (FALSE);
 109     return Status;
 110   }
 111
 112   ASSERT (NumProtocols != 0);
 113
 114   // Get the list of protocols supported by SCP firmware on the platform.
 115   Status = BaseProtocol->DiscoverListProtocols (
 116              BaseProtocol,
 117              &SupportedListSize,
 118              SupportedList
 119              );
 120   if (EFI_ERROR (Status)) {
 121     ASSERT (FALSE);
 122     return Status;
 123   }
 124
 125   // Install supported protocol on ImageHandle.
 126   for (Index = 0; Index < NumProtocols; Index++) {
 127     ProtocolNo = SupportedList[Index] & PROTOCOL_ID_MASK;
 128     if (ProtocolInitFxns[ProtocolNo].Init != NULL) {
 129       Status = ProtocolInitFxns[ProtocolNo].Init (&ImageHandle);
 130       if (EFI_ERROR (Status)) {
 131         ASSERT (FALSE);
 132         return Status;
 133       }
 134     }
 135   }
 136
 137   return EFI_SUCCESS;
 138 }