2 files changed, 130 insertions, 0 deletions
diff --git a/Lessons/Lesson_28/UefiLessonsPkg/AcpiInfo/AcpiInfo.c b/Lessons/Lesson_28/UefiLessonsPkg/AcpiInfo/AcpiInfo.c
new file mode 100644
index 0000000..0511f59
--- /dev/null
+++ b/Lessons/Lesson_28/UefiLessonsPkg/AcpiInfo/AcpiInfo.c
@@ -0,0 +1,106 @@
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiLib.h>
+
+#include <Library/BaseMemoryLib.h>
+#include <Protocol/Shell.h>
+
+EFI_STATUS
+EFIAPI
+UefiMain (
+  IN EFI_HANDLE        ImageHandle,
+  IN EFI_SYSTEM_TABLE  *SystemTable
+  )
+{
+  EFI_SHELL_PROTOCOL* ShellProtocol;
+  EFI_STATUS Status = gBS->LocateProtocol(
+    &gEfiShellProtocolGuid,
+    NULL,
+    (VOID **)&ShellProtocol
+  );
+
+  if (EFI_ERROR(Status)) {
+    Print(L"Can't open EFI_SHELL_PROTOCOL: %r\n", Status);
+    return EFI_SUCCESS;
+  }
+
+  EFI_ACPI_6_3_ROOT_SYSTEM_DESCRIPTION_POINTER* RSDP = NULL;
+
+  for (UINTN i=0; i<SystemTable->NumberOfTableEntries; i++) {
+    if (CompareGuid(&(SystemTable->ConfigurationTable[i].VendorGuid), &gEfiAcpi20TableGuid)) {
+      Print(L"RSDP table is placed at %p\n\n", SystemTable->ConfigurationTable[i].VendorTable);
+      RSDP = SystemTable->ConfigurationTable[i].VendorTable;
+    }
+  }
+
+  if (!RSDP) {
+    Print(L"No ACPI2.0 table was found in the system\n");
+    return EFI_SUCCESS;
+  }
+
+  if (((CHAR8)((RSDP->Signature >>  0) & 0xFF) != 'R') ||
+      ((CHAR8)((RSDP->Signature >>  8) & 0xFF) != 'S') ||
+      ((CHAR8)((RSDP->Signature >> 16) & 0xFF) != 'D') ||
+      ((CHAR8)((RSDP->Signature >> 24) & 0xFF) != ' ') ||
+      ((CHAR8)((RSDP->Signature >> 32) & 0xFF) != 'P') ||
+      ((CHAR8)((RSDP->Signature >> 40) & 0xFF) != 'T') ||
+      ((CHAR8)((RSDP->Signature >> 48) & 0xFF) != 'R') ||
+      ((CHAR8)((RSDP->Signature >> 56) & 0xFF) != ' ')) {
+    Print(L"Error! RSDP signature is not valid!\n");
+    return EFI_SUCCESS;
+  }
+
+  Print(L"System description tables:\n");
+  Print(L"\tRSDT table is placed at address %p\n", RSDP->RsdtAddress);
+  Print(L"\tXSDT table is placed at address %p\n", RSDP->XsdtAddress);
+  Print(L"\n");
+
+  EFI_ACPI_DESCRIPTION_HEADER* XSDT = (EFI_ACPI_DESCRIPTION_HEADER*)RSDP->XsdtAddress;
+  if (((CHAR8)((XSDT->Signature >>  0) & 0xFF) != 'X') ||
+      ((CHAR8)((XSDT->Signature >>  8) & 0xFF) != 'S') ||
+      ((CHAR8)((XSDT->Signature >> 16) & 0xFF) != 'D') ||
+      ((CHAR8)((XSDT->Signature >> 24) & 0xFF) != 'T')) {
+    Print(L"Error! XSDT signature is not valid!\n");
+    return EFI_SUCCESS;
+  }
+
+  Print(L"Main ACPI tables:\n");
+  UINT64 offset = sizeof(EFI_ACPI_DESCRIPTION_HEADER);
+  while (offset < XSDT->Length) {
+    UINT64* table_address = (UINT64*)((UINT8*)XSDT + offset);
+    EFI_ACPI_6_3_COMMON_HEADER* table = (EFI_ACPI_6_3_COMMON_HEADER*)(*table_address);
+    CHAR16 TableName[5];
+    TableName[0] = (CHAR16)((table->Signature>> 0)&0xFF);
+    TableName[1] = (CHAR16)((table->Signature>> 8)&0xFF);
+    TableName[2] = (CHAR16)((table->Signature>>16)&0xFF);
+    TableName[3] = (CHAR16)((table->Signature>>24)&0xFF);
+    TableName[4] = 0;
+
+    Print(L"\t%s table is placed at address %p with length 0x%x\n",
+                                             TableName,
+                                             table,
+                                             table->Length);
+    CHAR16 FileName[9] = {0};
+    StrCpyS(FileName, 9, TableName);
+    StrCatS(FileName, 9, L".aml");
+    SHELL_FILE_HANDLE FileHandle;
+    Status = ShellProtocol->OpenFileByName(FileName,
+                                           &FileHandle,
+                                           EFI_FILE_MODE_CREATE | EFI_FILE_MODE_WRITE | EFI_FILE_MODE_READ);
+    if (!EFI_ERROR(Status)) {
+      UINTN size = table->Length;
+      Status = ShellProtocol->WriteFile(FileHandle, &size, (VOID*)table);
+      if (EFI_ERROR(Status)) {
+        Print(L"Error in WriteFile: %r\n", Status);
+      }
+      Status = ShellProtocol->CloseFile(FileHandle);
+      if (EFI_ERROR(Status)) {
+        Print(L"Error in CloseFile: %r\n", Status);
+      }
+    } else {
+      Print(L"Error in OpenFileByName: %r\n", Status);
+    }
+    offset += sizeof(UINT64);
+  }
+
+  return EFI_SUCCESS;
+}
diff --git a/Lessons/Lesson_28/UefiLessonsPkg/AcpiInfo/AcpiInfo.inf b/Lessons/Lesson_28/UefiLessonsPkg/AcpiInfo/AcpiInfo.inf
new file mode 100644
index 0000000..53d0356
--- /dev/null
+++ b/Lessons/Lesson_28/UefiLessonsPkg/AcpiInfo/AcpiInfo.inf
@@ -0,0 +1,24 @@
+[Defines]
+  INF_VERSION                    = 1.25
+  BASE_NAME                      = AcpiInfo
+  FILE_GUID                      = 18998798-69a2-4ab5-9ffc-a8ee2494b029
+  MODULE_TYPE                    = UEFI_APPLICATION
+  VERSION_STRING                 = 1.0
+  ENTRY_POINT                    = UefiMain
+
+[Sources]
+  AcpiInfo.c
+
+[Packages]
+  MdePkg/MdePkg.dec
+
+[LibraryClasses]
+  UefiApplicationEntryPoint
+  UefiLib
+
+[Guids]
+  gEfiAcpi20TableGuid
+
+[Protocols]
+  gEfiShellProtocolGuid
+