ArmPkg/Drivers/ArmScmiDxe/ScmiDxe.c

   1 /** @file
   2
   3   Copyright (c) 2017-2021, Arm Limited. All rights reserved.<BR>
   4
   5   SPDX-License-Identifier: BSD-2-Clause-Patent
   6
   7   @par Specification Reference:
   8   - Arm System Control and Management Interface - Platform Design Document
   9     (https://developer.arm.com/documentation/den0056/)
  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   { ScmiProtocolIdBase,        ScmiBaseProtocolInit        },
  28   { ScmiProtocolIdPerformance, ScmiPerformanceProtocolInit },
  29   { ScmiProtocolIdClock,       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 == ScmiProtocolIdBase);
  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   // Accept any version between SCMI v1.0 and SCMI v2.0
  90   if ((Version < BASE_PROTOCOL_VERSION_V1) ||
  91       (Version > BASE_PROTOCOL_VERSION_V2))
  92   {
  93     ASSERT (FALSE);
  94     return EFI_UNSUPPORTED;
  95   }
  96
  97   // Apart from Base protocol, SCMI may implement various other protocols,
  98   // query total protocols implemented by the SCP firmware.
  99   NumProtocols = 0;
 100   Status       = BaseProtocol->GetTotalProtocols (BaseProtocol, &NumProtocols);
 101   if (EFI_ERROR (Status)) {
 102     ASSERT (FALSE);
 103     return Status;
 104   }
 105
 106   ASSERT (NumProtocols != 0);
 107
 108   SupportedListSize = (NumProtocols * sizeof (*SupportedList));
 109
 110   Status = gBS->AllocatePool (
 111                   EfiBootServicesData,
 112                   SupportedListSize,
 113                   (VOID **)&SupportedList
 114                   );
 115   if (EFI_ERROR (Status)) {
 116     ASSERT (FALSE);
 117     return Status;
 118   }
 119
 120   // Get the list of protocols supported by SCP firmware on the platform.
 121   Status = BaseProtocol->DiscoverListProtocols (
 122                            BaseProtocol,
 123                            &SupportedListSize,
 124                            SupportedList
 125                            );
 126   if (EFI_ERROR (Status)) {
 127     gBS->FreePool (SupportedList);
 128     ASSERT (FALSE);
 129     return Status;
 130   }
 131
 132   // Install supported protocol on ImageHandle.
 133   for (ProtocolIndex = 1; ProtocolIndex < ARRAY_SIZE (Protocols);
 134        ProtocolIndex++)
 135   {
 136     for (Index = 0; Index < NumProtocols; Index++) {
 137       if (Protocols[ProtocolIndex].Id == SupportedList[Index]) {
 138         Status = Protocols[ProtocolIndex].InitFn (&ImageHandle);
 139         if (EFI_ERROR (Status)) {
 140           ASSERT_EFI_ERROR (Status);
 141           return Status;
 142         }
 143
 144         break;
 145       }
 146     }
 147   }
 148
 149   gBS->FreePool (SupportedList);
 150
 151   return EFI_SUCCESS;
 152 }