OvmfPkg/Csm/CsmSupportLib/LegacyInterrupt.c

   1 /** @file
   2   Legacy Interrupt Support
   3
   4   Copyright (c) 2006 - 2011, Intel Corporation. All rights reserved.<BR>
   5
   6   This program and the accompanying materials are
   7   licensed and made available under the terms and conditions of the BSD License
   8   which accompanies this distribution.  The full text of the license may be found at
   9   http://opensource.org/licenses/bsd-license.php
  10
  11   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  12   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  13
  14 **/
  15
  16 #include "LegacyInterrupt.h"
  17
  18 //
  19 // Handle for the Legacy Interrupt Protocol instance produced by this driver
  20 //
  21 STATIC EFI_HANDLE mLegacyInterruptHandle = NULL;
  22
  23 //
  24 // The Legacy Interrupt Protocol instance produced by this driver
  25 //
  26 STATIC EFI_LEGACY_INTERRUPT_PROTOCOL mLegacyInterrupt = {
  27   GetNumberPirqs,
  28   GetLocation,
  29   ReadPirq,
  30   WritePirq
  31 };
  32
  33 STATIC UINT8 PirqReg[MAX_PIRQ_NUMBER] = { PIRQA, PIRQB, PIRQC, PIRQD, PIRQE, PIRQF, PIRQG, PIRQH };
  34
  35
  36 /**
  37   Return the number of PIRQs supported by this chipset.
  38
  39   @param[in]  This         Pointer to LegacyInterrupt Protocol
  40   @param[out] NumberPirqs  The pointer to return the max IRQ number supported
  41
  42   @retval EFI_SUCCESS   Max PIRQs successfully returned
  43
  44 **/
  45 EFI_STATUS
  46 EFIAPI
  47 GetNumberPirqs (
  48   IN  EFI_LEGACY_INTERRUPT_PROTOCOL  *This,
  49   OUT UINT8                          *NumberPirqs
  50   )
  51 {
  52   *NumberPirqs = MAX_PIRQ_NUMBER;
  53
  54   return EFI_SUCCESS;
  55 }
  56
  57
  58 /**
  59   Return PCI location of this device.
  60   $PIR table requires this info.
  61
  62   @param[in]   This                - Protocol instance pointer.
  63   @param[out]  Bus                 - PCI Bus
  64   @param[out]  Device              - PCI Device
  65   @param[out]  Function            - PCI Function
  66
  67   @retval  EFI_SUCCESS   Bus/Device/Function returned
  68
  69 **/
  70 EFI_STATUS
  71 EFIAPI
  72 GetLocation (
  73   IN  EFI_LEGACY_INTERRUPT_PROTOCOL  *This,
  74   OUT UINT8                          *Bus,
  75   OUT UINT8                          *Device,
  76   OUT UINT8                          *Function
  77   )
  78 {
  79   *Bus      = LEGACY_INT_BUS;
  80   *Device   = LEGACY_INT_DEV;
  81   *Function = LEGACY_INT_FUNC;
  82
  83   return EFI_SUCCESS;
  84 }
  85
  86
  87 /**
  88   Builds the PCI configuration address for the register specified by PirqNumber
  89
  90   @param[in]  PirqNumber - The PIRQ number to build the PCI configuration address for
  91
  92   @return  The PCI Configuration address for the PIRQ
  93 **/
  94 UINTN
  95 GetAddress (
  96   UINT8  PirqNumber
  97   )
  98 {
  99   return PCI_LIB_ADDRESS(
 100           LEGACY_INT_BUS,
 101           LEGACY_INT_DEV,
 102           LEGACY_INT_FUNC,
 103           PirqReg[PirqNumber]
 104           );
 105 }
 106
 107 /**
 108   Read the given PIRQ register
 109
 110   @param[in]  This        Protocol instance pointer
 111   @param[in]  PirqNumber  The Pirq register 0 = A, 1 = B etc
 112   @param[out] PirqData    Value read
 113
 114   @retval EFI_SUCCESS   Decoding change affected.
 115   @retval EFI_INVALID_PARAMETER   Invalid PIRQ number
 116
 117 **/
 118 EFI_STATUS
 119 EFIAPI
 120 ReadPirq (
 121   IN  EFI_LEGACY_INTERRUPT_PROTOCOL  *This,
 122   IN  UINT8                          PirqNumber,
 123   OUT UINT8                          *PirqData
 124   )
 125 {
 126   if (PirqNumber >= MAX_PIRQ_NUMBER) {
 127     return EFI_INVALID_PARAMETER;
 128   }
 129
 130   *PirqData = PciRead8 (GetAddress (PirqNumber));
 131   *PirqData = (UINT8) (*PirqData & 0x7f);
 132
 133   return EFI_SUCCESS;
 134 }
 135
 136
 137 /**
 138   Write the given PIRQ register
 139
 140   @param[in]  This        Protocol instance pointer
 141   @param[in]  PirqNumber  The Pirq register 0 = A, 1 = B etc
 142   @param[out] PirqData    Value to write
 143
 144   @retval EFI_SUCCESS   Decoding change affected.
 145   @retval EFI_INVALID_PARAMETER   Invalid PIRQ number
 146
 147 **/
 148 EFI_STATUS
 149 EFIAPI
 150 WritePirq (
 151   IN  EFI_LEGACY_INTERRUPT_PROTOCOL  *This,
 152   IN  UINT8                          PirqNumber,
 153   IN  UINT8                          PirqData
 154   )
 155 {
 156   if (PirqNumber >= MAX_PIRQ_NUMBER) {
 157     return EFI_INVALID_PARAMETER;
 158   }
 159
 160   PciWrite8 (GetAddress (PirqNumber), PirqData);
 161   return EFI_SUCCESS;
 162 }
 163
 164
 165 /**
 166   Initialize Legacy Interrupt support
 167
 168   @retval EFI_SUCCESS   Successfully initialized
 169
 170 **/
 171 EFI_STATUS
 172 LegacyInterruptInstall (
 173   VOID
 174   )
 175 {
 176   EFI_STATUS  Status;
 177
 178   //
 179   // Make sure the Legacy Interrupt Protocol is not already installed in the system
 180   //
 181   ASSERT_PROTOCOL_ALREADY_INSTALLED(NULL, &gEfiLegacyInterruptProtocolGuid);
 182
 183   //
 184   // Make a new handle and install the protocol
 185   //
 186   Status = gBS->InstallMultipleProtocolInterfaces (
 187                   &mLegacyInterruptHandle,
 188                   &gEfiLegacyInterruptProtocolGuid,
 189                   &mLegacyInterrupt,
 190                   NULL
 191                   );
 192   ASSERT_EFI_ERROR(Status);
 193
 194   return Status;
 195 }
 196