1 | /** @file -- MmCommunicationPei.c
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2 | Provides an interface to send MM request in PEI
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3 |
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4 | Copyright (c) 2016-2021, Arm Limited. All rights reserved.<BR>
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5 | Copyright (c) Microsoft Corporation.
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6 | SPDX-License-Identifier: BSD-2-Clause-Patent
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7 | **/
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8 |
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9 | #include <PiPei.h>
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10 | #include <IndustryStandard/ArmStdSmc.h>
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11 | #include <IndustryStandard/MmCommunicate.h>
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12 |
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13 | #include <Protocol/MmCommunication.h>
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14 | #include <Ppi/MmCommunication.h>
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15 |
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16 | #include <Library/BaseLib.h>
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17 | #include <Library/BaseMemoryLib.h>
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18 | #include <Library/ArmFfaLib.h>
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19 | #include <Library/ArmSmcLib.h>
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20 | #include <Library/DebugLib.h>
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21 | #include <Library/PcdLib.h>
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22 | #include <Library/PeimEntryPoint.h>
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23 | #include <Library/PeiServicesLib.h>
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24 |
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25 | //
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26 | // Partition ID if FF-A support is enabled
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27 | //
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28 | STATIC UINT16 mPartId;
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29 | STATIC UINT16 mStMmPartId;
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30 |
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31 | /**
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32 | Check mm communication compatibility when use SPM_MM.
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33 |
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34 | **/
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35 | STATIC
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36 | EFI_STATUS
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37 | EFIAPI
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38 | GetMmCompatibility (
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39 | VOID
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40 | )
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41 | {
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42 | EFI_STATUS Status;
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43 | UINT32 MmVersion;
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44 | ARM_SMC_ARGS MmVersionArgs;
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45 |
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46 | // MM_VERSION uses SMC32 calling conventions
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47 | MmVersionArgs.Arg0 = ARM_SMC_ID_MM_VERSION_AARCH32;
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48 |
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49 | ArmCallSmc (&MmVersionArgs);
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50 | if (MmVersionArgs.Arg0 == ARM_SMC_MM_RET_NOT_SUPPORTED) {
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51 | return EFI_UNSUPPORTED;
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52 | }
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53 |
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54 | MmVersion = MmVersionArgs.Arg0;
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55 |
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56 | if ((MM_MAJOR_VER (MmVersion) == MM_CALLER_MAJOR_VER) &&
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57 | (MM_MINOR_VER (MmVersion) >= MM_CALLER_MINOR_VER))
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58 | {
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59 | DEBUG ((
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60 | DEBUG_INFO,
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61 | "MM Version: Major=0x%x, Minor=0x%x\n",
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62 | MM_MAJOR_VER (MmVersion),
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63 | MM_MINOR_VER (MmVersion)
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64 | ));
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65 | Status = EFI_SUCCESS;
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66 | } else {
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67 | DEBUG ((
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68 | DEBUG_ERROR,
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69 | "Incompatible MM Versions.\n Current Version: Major=0x%x, Minor=0x%x.\n Expected: Major=0x%x, Minor>=0x%x.\n",
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70 | MM_MAJOR_VER (MmVersion),
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71 | MM_MINOR_VER (MmVersion),
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72 | MM_CALLER_MAJOR_VER,
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73 | MM_CALLER_MINOR_VER
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74 | ));
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75 | Status = EFI_UNSUPPORTED;
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76 | }
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77 |
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78 | return Status;
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79 | }
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80 |
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81 | /**
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82 | Check mm communication compatibility when use FF-A.
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83 |
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84 | **/
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85 | STATIC
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86 | EFI_STATUS
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87 | EFIAPI
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88 | GetFfaCompatibility (
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89 | VOID
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90 | )
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91 | {
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92 | EFI_STATUS Status;
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93 | UINT16 CurrentMajorVersion;
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94 | UINT16 CurrentMinorVersion;
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95 |
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96 | Status = ArmFfaLibGetVersion (
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97 | ARM_FFA_MAJOR_VERSION,
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98 | ARM_FFA_MINOR_VERSION,
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99 | &CurrentMajorVersion,
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100 | &CurrentMinorVersion
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101 | );
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102 | if (EFI_ERROR (Status)) {
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103 | return EFI_UNSUPPORTED;
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104 | }
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105 |
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106 | if ((ARM_FFA_MAJOR_VERSION != CurrentMajorVersion) ||
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107 | (ARM_FFA_MINOR_VERSION > CurrentMinorVersion))
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108 | {
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109 | DEBUG ((
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110 | DEBUG_INFO,
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111 | "Incompatible FF-A Versions for MM_COMM.\n" \
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112 | "Request Version: Major=0x%x, Minor=0x%x.\n" \
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113 | "Current Version: Major=0x%x, Minor>=0x%x.\n",
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114 | ARM_FFA_MAJOR_VERSION,
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115 | ARM_FFA_MINOR_VERSION,
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116 | CurrentMajorVersion,
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117 | CurrentMinorVersion
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118 | ));
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119 | return EFI_UNSUPPORTED;
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120 | }
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121 |
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122 | DEBUG ((
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123 | DEBUG_INFO,
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124 | "FF-A Version for MM_COMM: Major=0x%x, Minor=0x%x\n",
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125 | CurrentMajorVersion,
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126 | CurrentMinorVersion
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127 | ));
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128 |
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129 | return EFI_SUCCESS;
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130 | }
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131 |
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132 | /**
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133 | Initialize communication via FF-A.
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134 |
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135 | **/
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136 | STATIC
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137 | EFI_STATUS
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138 | EFIAPI
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139 | InitializeFfaCommunication (
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140 | VOID
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141 | )
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142 | {
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143 | EFI_STATUS Status;
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144 | VOID *TxBuffer;
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145 | UINT64 TxBufferSize;
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146 | VOID *RxBuffer;
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147 | UINT64 RxBufferSize;
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148 | EFI_FFA_PART_INFO_DESC *StmmPartInfo;
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149 | UINT32 Count;
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150 | UINT32 Size;
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151 |
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152 | Status = ArmFfaLibPartitionIdGet (&mPartId);
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153 | if (EFI_ERROR (Status)) {
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154 | DEBUG ((
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155 | DEBUG_ERROR,
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156 | "Failed to get partition id. Status: %r\n",
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157 | Status
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158 | ));
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159 | return Status;
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160 | }
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161 |
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162 | Status = ArmFfaLibGetRxTxBuffers (
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163 | &TxBuffer,
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164 | &TxBufferSize,
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165 | &RxBuffer,
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166 | &RxBufferSize
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167 | );
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168 | if (EFI_ERROR (Status)) {
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169 | DEBUG ((
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170 | DEBUG_ERROR,
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171 | "Failed to get Rx/Tx Buffer. Status: %r\n",
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172 | Status
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173 | ));
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174 | return Status;
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175 | }
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176 |
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177 | Status = ArmFfaLibPartitionInfoGet (
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178 | &gEfiMmCommunication2ProtocolGuid,
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179 | FFA_PART_INFO_FLAG_TYPE_DESC,
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180 | &Count,
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181 | &Size
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182 | );
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183 | if (EFI_ERROR (Status)) {
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184 | DEBUG ((
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185 | DEBUG_ERROR,
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186 | "Failed to get Stmm(%g) partition Info. Status: %r\n",
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187 | &gEfiMmCommunication2ProtocolGuid,
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188 | Status
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189 | ));
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190 | return Status;
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191 | }
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192 |
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193 | if ((Count != 1) || (Size < sizeof (EFI_FFA_PART_INFO_DESC))) {
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194 | Status = EFI_INVALID_PARAMETER;
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195 | DEBUG ((
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196 | DEBUG_ERROR,
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197 | "Invalid partition Info(%g). Count: %d, Size: %d\n",
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198 | &gEfiMmCommunication2ProtocolGuid,
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199 | Count,
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200 | Size
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201 | ));
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202 | goto ErrorHandler;
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203 | }
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204 |
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205 | StmmPartInfo = (EFI_FFA_PART_INFO_DESC *)RxBuffer;
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206 |
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207 | if ((StmmPartInfo->PartitionProps & FFA_PART_PROP_RECV_DIRECT_REQ) == 0x00) {
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208 | Status = EFI_UNSUPPORTED;
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209 | DEBUG ((DEBUG_ERROR, "StandaloneMm doesn't receive DIRECT_MSG_REQ...\n"));
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210 | goto ErrorHandler;
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211 | }
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212 |
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213 | mStMmPartId = StmmPartInfo->PartitionId;
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214 |
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215 | ErrorHandler:
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216 | ArmFfaLibRxRelease (mPartId);
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217 | return Status;
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218 | }
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219 |
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220 | /**
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221 | Initialize mm communication.
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222 |
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223 | **/
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224 | STATIC
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225 | EFI_STATUS
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226 | EFIAPI
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227 | InitializeCommunication (
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228 | VOID
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229 | )
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230 | {
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231 | EFI_STATUS Status;
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232 |
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233 | Status = EFI_UNSUPPORTED;
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234 |
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235 | if (IsFfaSupported ()) {
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236 | Status = GetFfaCompatibility ();
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237 | if (!EFI_ERROR (Status)) {
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238 | Status = InitializeFfaCommunication ();
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239 | }
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240 | } else {
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241 | Status = GetMmCompatibility ();
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242 | // No further initialisation required for SpmMM
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243 | }
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244 |
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245 | return Status;
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246 | }
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247 |
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248 | /**
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249 | Send mm communicate request via FF-A.
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250 |
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251 | @retval EFI_SUCCESS
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252 | @retval Others Error.
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253 |
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254 | **/
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255 | STATIC
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256 | EFI_STATUS
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257 | EFIAPI
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258 | SendFfaMmCommunicate (
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259 | VOID
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260 | )
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261 | {
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262 | EFI_STATUS Status;
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263 | DIRECT_MSG_ARGS CommunicateArgs;
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264 |
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265 | ZeroMem (&CommunicateArgs, sizeof (DIRECT_MSG_ARGS));
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266 |
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267 | CommunicateArgs.Arg0 = (UINTN)PcdGet64 (PcdMmBufferBase);
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268 |
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269 | Status = ArmFfaLibMsgSendDirectReq (
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270 | mStMmPartId,
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271 | 0,
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272 | &CommunicateArgs
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273 | );
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274 |
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275 | while (Status == EFI_INTERRUPT_PENDING) {
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276 | // We are assuming vCPU0 of the StMM SP since it is UP.
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277 | Status = ArmFfaLibRun (mStMmPartId, 0x00);
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278 | }
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279 |
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280 | return Status;
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281 | }
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282 |
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283 | /**
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284 | Convert SmcMmRet value to EFI_STATUS.
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285 |
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286 | @param[in] SmcMmRet Mm return code
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287 |
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288 | @retval EFI_SUCCESS
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289 | @retval Others Error status correspond to SmcMmRet
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290 |
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291 | **/
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292 | STATIC
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293 | EFI_STATUS
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294 | SmcMmRetToEfiStatus (
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295 | IN UINTN SmcMmRet
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296 | )
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297 | {
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298 | switch ((UINT32)SmcMmRet) {
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299 | case ARM_SMC_MM_RET_SUCCESS:
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300 | return EFI_SUCCESS;
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301 | case ARM_SMC_MM_RET_INVALID_PARAMS:
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302 | return EFI_INVALID_PARAMETER;
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303 | case ARM_SMC_MM_RET_DENIED:
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304 | return EFI_ACCESS_DENIED;
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305 | case ARM_SMC_MM_RET_NO_MEMORY:
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306 | return EFI_OUT_OF_RESOURCES;
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307 | default:
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308 | return EFI_ACCESS_DENIED;
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309 | }
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310 | }
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311 |
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312 | /**
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313 | Send mm communicate request via SPM_MM.
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314 |
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315 | @retval EFI_SUCCESS
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316 | @retval Others Error.
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317 |
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318 | **/
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319 | STATIC
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320 | EFI_STATUS
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321 | EFIAPI
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322 | SendSpmMmCommunicate (
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323 | VOID
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324 | )
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325 | {
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326 | ARM_SMC_ARGS CommunicateSmcArgs;
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327 |
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328 | ZeroMem (&CommunicateSmcArgs, sizeof (ARM_SMC_ARGS));
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329 |
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330 | // SMC Function ID
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331 | CommunicateSmcArgs.Arg0 = ARM_SMC_ID_MM_COMMUNICATE_AARCH64;
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332 |
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333 | // Cookie
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334 | CommunicateSmcArgs.Arg1 = 0;
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335 |
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336 | // comm_buffer_address (64-bit physical address)
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337 | CommunicateSmcArgs.Arg2 = (UINTN)PcdGet64 (PcdMmBufferBase);
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338 |
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339 | // comm_size_address (not used, indicated by setting to zero)
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340 | CommunicateSmcArgs.Arg3 = 0;
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341 |
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342 | // Call the Standalone MM environment.
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343 | ArmCallSmc (&CommunicateSmcArgs);
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344 |
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345 | return SmcMmRetToEfiStatus (CommunicateSmcArgs.Arg0);
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346 | }
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347 |
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348 | /**
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349 | MmCommunicationPeim
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350 | Communicates with a registered handler.
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351 | This function provides a service to send and receive messages from a registered UEFI service during PEI.
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352 |
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353 | @param[in] This The EFI_PEI_MM_COMMUNICATION_PPI instance.
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354 | @param[in, out] CommBuffer Pointer to the data buffer
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355 | @param[in, out] CommSize The size of the data buffer being passed in. On exit, the
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356 | size of data being returned. Zero if the handler does not
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357 | wish to reply with any data.
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358 |
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359 | @retval EFI_SUCCESS The message was successfully posted.
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360 | @retval EFI_INVALID_PARAMETER CommBuffer or CommSize was NULL, or *CommSize does not
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361 | match MessageLength + sizeof (EFI_MM_COMMUNICATE_HEADER).
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362 | @retval EFI_BAD_BUFFER_SIZE The buffer is too large for the MM implementation.
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363 | If this error is returned, the MessageLength field
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364 | in the CommBuffer header or the integer pointed by
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365 | CommSize, are updated to reflect the maximum payload
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366 | size the implementation can accommodate.
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367 | @retval EFI_ACCESS_DENIED The CommunicateBuffer parameter or CommSize parameter,
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368 | if not omitted, are in address range that cannot be
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369 | accessed by the MM environment.
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370 | **/
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371 | STATIC
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372 | EFI_STATUS
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373 | EFIAPI
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374 | MmCommunicationPeim (
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375 | IN CONST EFI_PEI_MM_COMMUNICATION_PPI *This,
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376 | IN OUT VOID *CommBuffer,
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377 | IN OUT UINTN *CommSize
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378 | )
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379 | {
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380 | EFI_MM_COMMUNICATE_HEADER *CommunicateHeader;
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381 | EFI_MM_COMMUNICATE_HEADER *TempCommHeader;
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382 | EFI_STATUS Status;
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383 | UINTN BufferSize;
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384 |
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385 | //
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386 | // Check parameters
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387 | //
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388 | if ((CommBuffer == NULL) || (CommSize == NULL)) {
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389 | ASSERT (CommBuffer != NULL);
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390 | ASSERT (CommSize != NULL);
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391 | return EFI_INVALID_PARAMETER;
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392 | }
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393 |
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394 | // If the length of the CommBuffer is 0 then return the expected length.
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395 | // This case can be used by the consumer of this driver to find out the
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396 | // max size that can be used for allocating CommBuffer.
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397 | if ((*CommSize == 0) || (*CommSize > (UINTN)PcdGet64 (PcdMmBufferSize))) {
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398 | DEBUG ((
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399 | DEBUG_ERROR,
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400 | "%a Invalid CommSize value 0x%llx!\n",
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401 | __func__,
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402 | *CommSize
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403 | ));
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404 | *CommSize = (UINTN)PcdGet64 (PcdMmBufferSize);
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405 | return EFI_BAD_BUFFER_SIZE;
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406 | }
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407 |
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408 | // Given CommBuffer is not NULL here, we use it to test the legitimacy of CommSize.
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409 | TempCommHeader = (EFI_MM_COMMUNICATE_HEADER *)(UINTN)CommBuffer;
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410 |
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411 | // CommBuffer is a mandatory parameter. Hence, Rely on
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412 | // MessageLength + Header to ascertain the
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413 | // total size of the communication payload rather than
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414 | // rely on optional CommSize parameter
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415 | BufferSize = TempCommHeader->MessageLength +
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416 | sizeof (TempCommHeader->HeaderGuid) +
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417 | sizeof (TempCommHeader->MessageLength);
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418 |
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419 | //
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420 | // If CommSize is supplied it must match MessageLength + sizeof (EFI_MM_COMMUNICATE_HEADER);
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421 | //
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422 | if (*CommSize != BufferSize) {
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423 | DEBUG ((
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424 | DEBUG_ERROR,
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425 | "%a Unexpected CommSize value, has: 0x%llx vs. expected: 0x%llx!\n",
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426 | __func__,
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427 | *CommSize,
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428 | BufferSize
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429 | ));
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430 | return EFI_INVALID_PARAMETER;
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431 | }
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432 |
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433 | // Now we know that the size is something we can handle, copy it over to the designated comm buffer.
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434 | CommunicateHeader = (EFI_MM_COMMUNICATE_HEADER *)(UINTN)(PcdGet64 (PcdMmBufferBase));
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435 |
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436 | CopyMem (CommunicateHeader, CommBuffer, *CommSize);
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437 |
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438 | if (IsFfaSupported ()) {
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439 | Status = SendFfaMmCommunicate ();
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440 | } else {
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441 | Status = SendSpmMmCommunicate ();
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442 | }
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443 |
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444 | if (!EFI_ERROR (Status)) {
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445 | // On successful return, the size of data being returned is inferred from
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446 | // MessageLength + Header.
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447 | BufferSize = CommunicateHeader->MessageLength +
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448 | sizeof (CommunicateHeader->HeaderGuid) +
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449 | sizeof (CommunicateHeader->MessageLength);
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450 | if (BufferSize > (UINTN)PcdGet64 (PcdMmBufferSize)) {
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451 | // Something bad has happened, we should have landed in ARM_SMC_MM_RET_NO_MEMORY
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452 | Status = EFI_BAD_BUFFER_SIZE;
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453 | DEBUG ((
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454 | DEBUG_ERROR,
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455 | "%a Returned buffer exceeds communication buffer limit. Has: 0x%llx vs. max: 0x%llx!\n",
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456 | __func__,
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457 | BufferSize,
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458 | (UINTN)PcdGet64 (PcdMmBufferSize)
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459 | ));
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460 | } else {
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461 | CopyMem (CommBuffer, CommunicateHeader, BufferSize);
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462 | *CommSize = BufferSize;
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463 | }
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464 | }
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465 |
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466 | return Status;
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467 | }
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468 |
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469 | //
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470 | // Module globals for the MM Communication PPI
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471 | //
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472 | STATIC CONST EFI_PEI_MM_COMMUNICATION_PPI mPeiMmCommunication = {
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473 | MmCommunicationPeim
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474 | };
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475 |
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476 | STATIC CONST EFI_PEI_PPI_DESCRIPTOR mPeiMmCommunicationPpi = {
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477 | (EFI_PEI_PPI_DESCRIPTOR_PPI | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST),
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478 | &gEfiPeiMmCommunicationPpiGuid,
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479 | (VOID *)&mPeiMmCommunication
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480 | };
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481 |
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482 | /**
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483 | Entry point of PEI MM Communication driver
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484 |
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485 | @param FileHandle Handle of the file being invoked.
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486 | Type EFI_PEI_FILE_HANDLE is defined in FfsFindNextFile().
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487 | @param PeiServices General purpose services available to every PEIM.
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488 |
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489 | @retval EFI_SUCCESS If the interface could be successfully installed
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490 | @retval Others Returned from PeiServicesInstallPpi()
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491 | **/
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492 | EFI_STATUS
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493 | EFIAPI
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494 | MmCommunicationPeiInitialize (
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495 | IN EFI_PEI_FILE_HANDLE FileHandle,
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496 | IN CONST EFI_PEI_SERVICES **PeiServices
|
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497 | )
|
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498 | {
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499 | EFI_STATUS Status;
|
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500 |
|
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501 | // Check that our static buffer is looking good.
|
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502 | // We are using PcdMmBufferBase to transfer variable data.
|
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503 | // We are not using the full size of the buffer since there is a cost
|
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504 | // of copying data between Normal and Secure World.
|
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505 | if ((PcdGet64 (PcdMmBufferBase) == 0) || (PcdGet64 (PcdMmBufferSize) == 0)) {
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506 | ASSERT (PcdGet64 (PcdMmBufferSize) > 0);
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507 | ASSERT (PcdGet64 (PcdMmBufferBase) != 0);
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508 | return EFI_UNSUPPORTED;
|
---|
509 | }
|
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510 |
|
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511 | // Check if we can make the MM call
|
---|
512 | Status = InitializeCommunication ();
|
---|
513 | if (EFI_ERROR (Status)) {
|
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514 | return Status;
|
---|
515 | }
|
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516 |
|
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517 | return PeiServicesInstallPpi (&mPeiMmCommunicationPpi);
|
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518 | }
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