ArmPkg/Drivers/ArmScmiDxe/ScmiDxe.c

   1 /** @file
   2
   3   Copyright (c) 2017-2018, Arm Limited. All rights reserved.
   4
   5   SPDX-License-Identifier: BSD-2-Clause-Patent
   6
   7   System Control and Management Interface V1.0
   8     http://infocenter.arm.com/help/topic/com.arm.doc.den0056a/
   9     DEN0056A_System_Control_and_Management_Interface.pdf
  10 **/
  11
  12 #include <Base.h>
  13 #include <Library/DebugLib.h>
  14 #include <Library/MemoryAllocationLib.h>
  15 #include <Library/UefiBootServicesTableLib.h>
  16 #include <Protocol/ArmScmiBaseProtocol.h>
  17 #include <Protocol/ArmScmiClockProtocol.h>
  18 #include <Protocol/ArmScmiPerformanceProtocol.h>
  19
  20 #include "ArmScmiBaseProtocolPrivate.h"
  21 #include "ArmScmiClockProtocolPrivate.h"
  22 #include "ArmScmiPerformanceProtocolPrivate.h"
  23 #include "ScmiDxe.h"
  24 #include "ScmiPrivate.h"
  25
  26 STATIC CONST SCMI_PROTOCOL_ENTRY Protocols[] = {
  27   { SCMI_PROTOCOL_ID_BASE, ScmiBaseProtocolInit },
  28   { SCMI_PROTOCOL_ID_PERFORMANCE, ScmiPerformanceProtocolInit },
  29   { SCMI_PROTOCOL_ID_CLOCK, ScmiClockProtocolInit }
  30 };
  31
  32 /** ARM SCMI driver entry point function.
  33
  34   This function installs the SCMI Base protocol and a list of other
  35   protocols is queried using the Base protocol. If protocol is supported,
  36   driver will call each protocol init function to install the protocol on
  37   the ImageHandle.
  38
  39   @param[in] ImageHandle     Handle to this EFI Image which will be used to
  40                              install Base, Clock and Performance protocols.
  41   @param[in] SystemTable     A pointer to boot time system table.
  42
  43   @retval EFI_SUCCESS       Driver initalized successfully.
  44   @retval EFI_UNSUPPORTED   If SCMI base protocol version is not supported.
  45   @retval !(EFI_SUCCESS)    Other errors.
  46 **/
  47 EFI_STATUS
  48 EFIAPI
  49 ArmScmiDxeEntryPoint (
  50   IN EFI_HANDLE             ImageHandle,
  51   IN EFI_SYSTEM_TABLE       *SystemTable
  52   )
  53 {
  54   EFI_STATUS          Status;
  55   SCMI_BASE_PROTOCOL  *BaseProtocol;
  56   UINT32              Version;
  57   UINT32              Index;
  58   UINT32              NumProtocols;
  59   UINT32              ProtocolIndex;
  60   UINT8               *SupportedList;
  61   UINT32              SupportedListSize;
  62
  63   // Every SCMI implementation must implement the base protocol.
  64   ASSERT (Protocols[0].Id == SCMI_PROTOCOL_ID_BASE);
  65
  66   Status = ScmiBaseProtocolInit (&ImageHandle);
  67   if (EFI_ERROR (Status)) {
  68     ASSERT (FALSE);
  69     return Status;
  70   }
  71
  72   Status = gBS->LocateProtocol (
  73                   &gArmScmiBaseProtocolGuid,
  74                   NULL,
  75                   (VOID**)&BaseProtocol
  76                   );
  77   if (EFI_ERROR (Status)) {
  78     ASSERT (FALSE);
  79     return Status;
  80   }
  81
  82   // Get SCMI Base protocol version.
  83   Status = BaseProtocol->GetVersion (BaseProtocol, &Version);
  84   if (EFI_ERROR (Status)) {
  85     ASSERT (FALSE);
  86     return Status;
  87   }
  88
  89   if (Version != BASE_PROTOCOL_VERSION) {
  90     ASSERT (FALSE);
  91     return EFI_UNSUPPORTED;
  92   }
  93
  94   // Apart from Base protocol, SCMI may implement various other protocols,
  95   // query total protocols implemented by the SCP firmware.
  96   NumProtocols = 0;
  97   Status = BaseProtocol->GetTotalProtocols (BaseProtocol, &NumProtocols);
  98   if (EFI_ERROR (Status)) {
  99     ASSERT (FALSE);
 100     return Status;
 101   }
 102
 103   ASSERT (NumProtocols != 0);
 104
 105   SupportedListSize = (NumProtocols * sizeof (*SupportedList));
 106
 107   Status = gBS->AllocatePool (
 108                   EfiBootServicesData,
 109                   SupportedListSize,
 110                   (VOID**)&SupportedList
 111                   );
 112   if (EFI_ERROR (Status)) {
 113     ASSERT (FALSE);
 114     return Status;
 115   }
 116
 117   // Get the list of protocols supported by SCP firmware on the platform.
 118   Status = BaseProtocol->DiscoverListProtocols (
 119                            BaseProtocol,
 120                            &SupportedListSize,
 121                            SupportedList
 122                            );
 123   if (EFI_ERROR (Status)) {
 124     gBS->FreePool (SupportedList);
 125     ASSERT (FALSE);
 126     return Status;
 127   }
 128
 129   // Install supported protocol on ImageHandle.
 130   for (ProtocolIndex = 1; ProtocolIndex < ARRAY_SIZE (Protocols);
 131        ProtocolIndex++) {
 132     for (Index = 0; Index < NumProtocols; Index++) {
 133       if (Protocols[ProtocolIndex].Id == SupportedList[Index]) {
 134         Status = Protocols[ProtocolIndex].InitFn (&ImageHandle);
 135         if (EFI_ERROR (Status)) {
 136           ASSERT_EFI_ERROR (Status);
 137           return Status;
 138         }
 139         break;
 140       }
 141     }
 142   }
 143
 144   gBS->FreePool (SupportedList);
 145
 146   return EFI_SUCCESS;
 147 }