DxeIpl: Fix ACPI reset register detection

CPU4004 · Jul 10, 2020 · f6ceca9 · f6ceca9
1 parent 748b0ea
commit f6ceca9
Showing 1 changed file with 23 additions and 7 deletions.
diff --git a/Legacy/BootPlatform/DxeIpl/LegacyTable.c b/Legacy/BootPlatform/DxeIpl/LegacyTable.c
@@ -307,12 +307,28 @@ PrepareFadtTable (
       );
   }
   if (Fadt->Header.Length >= OFFSET_OF (EFI_ACPI_3_0_FIXED_ACPI_DESCRIPTION_TABLE, ResetValue) + sizeof (Fadt->ResetValue)) {
-    CopyMem (
-      &AcpiDescription->RESET_REG,
-      &Fadt->ResetReg,
-      sizeof(EFI_ACPI_3_0_GENERIC_ADDRESS_STRUCTURE)
-      );
-    AcpiDescription->RESET_VALUE = Fadt->ResetValue;
+    //
+    // Ensure FADT register information is valid and can be trusted before using.
+    // If not, use universal register settings. See AcpiFadtEnableReset() in OcAcpiLib.
+    //
+    if (Fadt->ResetReg.Address != 0 && Fadt->ResetReg.RegisterBitWidth == 8) {
+      CopyMem (
+        &AcpiDescription->RESET_REG,
+        &Fadt->ResetReg,
+        sizeof(EFI_ACPI_3_0_GENERIC_ADDRESS_STRUCTURE)
+        );
+      AcpiDescription->RESET_VALUE = Fadt->ResetValue;
+    } else {
+      //
+      // Use mostly universal default of 0xCF9.
+      //
+      AcpiDescription->RESET_REG.Address = 0xCF9;
+      AcpiDescription->RESET_REG.AddressSpaceId = EFI_ACPI_3_0_SYSTEM_IO;
+      AcpiDescription->RESET_REG.RegisterBitWidth = 8;
+      AcpiDescription->RESET_REG.RegisterBitOffset = 0;
+      AcpiDescription->RESET_REG.AccessSize = EFI_ACPI_3_0_BYTE;
+      AcpiDescription->RESET_VALUE = 6;
+    }
   } else {
     //
     // ** CHANGE START **
@@ -322,7 +338,7 @@ PrepareFadtTable (
     AcpiDescription->RESET_REG.AddressSpaceId = EFI_ACPI_3_0_SYSTEM_IO;
     AcpiDescription->RESET_REG.RegisterBitWidth = 8;
     AcpiDescription->RESET_REG.RegisterBitOffset = 0;
-    AcpiDescription->RESET_REG.AccessSize = 1;
+    AcpiDescription->RESET_REG.AccessSize = EFI_ACPI_3_0_BYTE;
     AcpiDescription->RESET_VALUE = 0xFE;
     //
     // ** CHANGE END **