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_ENTRY Protocols[] = {
  33   { SCMI_PROTOCOL_ID_BASE, ScmiBaseProtocolInit },
  34   { SCMI_PROTOCOL_ID_PERFORMANCE, ScmiPerformanceProtocolInit },
  35   { SCMI_PROTOCOL_ID_CLOCK, ScmiClockProtocolInit }
  36 };
  37
  38 /** ARM SCMI driver entry point function.
  39
  40   This function installs the SCMI Base protocol and a list of other
  41   protocols is queried using the Base protocol. If protocol is supported,
  42   driver will call each protocol init function to install the protocol on
  43   the ImageHandle.
  44
  45   @param[in] ImageHandle     Handle to this EFI Image which will be used to
  46                              install Base, Clock and Performance protocols.
  47   @param[in] SystemTable     A pointer to boot time system table.
  48
  49   @retval EFI_SUCCESS       Driver initalized successfully.
  50   @retval EFI_UNSUPPORTED   If SCMI base protocol version is not supported.
  51   @retval !(EFI_SUCCESS)    Other errors.
  52 **/
  53 EFI_STATUS
  54 EFIAPI
  55 ArmScmiDxeEntryPoint (
  56   IN EFI_HANDLE             ImageHandle,
  57   IN EFI_SYSTEM_TABLE       *SystemTable
  58   )
  59 {
  60   EFI_STATUS          Status;
  61   SCMI_BASE_PROTOCOL  *BaseProtocol;
  62   UINT32              Version;
  63   UINT32              Index;
  64   UINT32              NumProtocols;
  65   UINT32              ProtocolIndex;
  66   UINT8               *SupportedList;
  67   UINT32              SupportedListSize;
  68
  69   // Every SCMI implementation must implement the base protocol.
  70   ASSERT (Protocols[0].Id == SCMI_PROTOCOL_ID_BASE);
  71
  72   Status = ScmiBaseProtocolInit (&ImageHandle);
  73   if (EFI_ERROR (Status)) {
  74     ASSERT (FALSE);
  75     return Status;
  76   }
  77
  78   Status = gBS->LocateProtocol (
  79                   &gArmScmiBaseProtocolGuid,
  80                   NULL,
  81                   (VOID**)&BaseProtocol
  82                   );
  83   if (EFI_ERROR (Status)) {
  84     ASSERT (FALSE);
  85     return Status;
  86   }
  87
  88   // Get SCMI Base protocol version.
  89   Status = BaseProtocol->GetVersion (BaseProtocol, &Version);
  90   if (EFI_ERROR (Status)) {
  91     ASSERT (FALSE);
  92     return Status;
  93   }
  94
  95   if (Version != BASE_PROTOCOL_VERSION) {
  96     ASSERT (FALSE);
  97     return EFI_UNSUPPORTED;
  98   }
  99
 100   // Apart from Base protocol, SCMI may implement various other protocols,
 101   // query total protocols implemented by the SCP firmware.
 102   NumProtocols = 0;
 103   Status = BaseProtocol->GetTotalProtocols (BaseProtocol, &NumProtocols);
 104   if (EFI_ERROR (Status)) {
 105     ASSERT (FALSE);
 106     return Status;
 107   }
 108
 109   ASSERT (NumProtocols != 0);
 110
 111   SupportedListSize = (NumProtocols * sizeof (*SupportedList));
 112
 113   Status = gBS->AllocatePool (
 114                   EfiBootServicesData,
 115                   SupportedListSize,
 116                   (VOID**)&SupportedList
 117                   );
 118   if (EFI_ERROR (Status)) {
 119     ASSERT (FALSE);
 120     return Status;
 121   }
 122
 123   // Get the list of protocols supported by SCP firmware on the platform.
 124   Status = BaseProtocol->DiscoverListProtocols (
 125                            BaseProtocol,
 126                            &SupportedListSize,
 127                            SupportedList
 128                            );
 129   if (EFI_ERROR (Status)) {
 130     gBS->FreePool (SupportedList);
 131     ASSERT (FALSE);
 132     return Status;
 133   }
 134
 135   // Install supported protocol on ImageHandle.
 136   for (ProtocolIndex = 1; ProtocolIndex < ARRAY_SIZE (Protocols);
 137        ProtocolIndex++) {
 138     for (Index = 0; Index < NumProtocols; Index++) {
 139       if (Protocols[ProtocolIndex].Id == SupportedList[Index]) {
 140         Status = Protocols[ProtocolIndex].InitFn (&ImageHandle);
 141         if (EFI_ERROR (Status)) {
 142           ASSERT_EFI_ERROR (Status);
 143           return Status;
 144         }
 145         break;
 146       }
 147     }
 148   }
 149
 150   gBS->FreePool (SupportedList);
 151
 152   return EFI_SUCCESS;
 153 }