[PATCH v1 1/1] ShellPkg: acpiview: Add GT Frame Number validation to GTDT parser

["Krzysztof Koch" <krzysztof.koch@arm.com>]

The ACPI 6.2 specification mandates that the Generic Timer (GT) Block
Timer Structures must have a frame number in the range 0-7.

Update the GTDT parser to warn if this condition is violated.

Signed-off-by: Krzysztof Koch <krzysztof.koch@arm.com>
---

The changes can be seen at: https://github.com/KrzysztofKoch1/edk2/tree/woa_528_acpiview_gt_frame_validate_v1

Notes:
    v1:
      - Add GTDT Frame Number checks [Krzysztof]

 ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Gtdt/GtdtParser.c | 47 +++++++++++++++++++-
 1 file changed, 45 insertions(+), 2 deletions(-)

diff --git a/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Gtdt/GtdtParser.c b/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Gtdt/GtdtParser.c
index f31c4a2761751c58d4b1d3eb75084e24ec318e7f..572e52385c54932b14630481e85a67d0b211966a 100644
--- a/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Gtdt/GtdtParser.c
+++ b/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Gtdt/GtdtParser.c
@@ -1,7 +1,7 @@
 /** @file
   GTDT table parser

-  Copyright (c) 2016 - 2018, ARM Limited. All rights reserved.
+  Copyright (c) 2016 - 2019, ARM Limited. All rights reserved.
   SPDX-License-Identifier: BSD-2-Clause-Patent

   @par Reference(s):
@@ -38,6 +38,21 @@ ValidateGtBlockTimerCount (
   IN VOID*  Context
   );

+/**
+  This function validates the GT Frame Number.
+
+  @param [in] Ptr     Pointer to the start of the field data.
+  @param [in] Context Pointer to context specific information e.g. this
+                      could be a pointer to the ACPI table header.
+**/
+STATIC
+VOID
+EFIAPI
+ValidateGtFrameNumber (
+  IN UINT8* Ptr,
+  IN VOID*  Context
+  );
+
 /**
   An ACPI_PARSER array describing the ACPI GTDT Table.
 **/
@@ -92,7 +107,7 @@ STATIC CONST ACPI_PARSER GtBlockParser[] = {
   An ACPI_PARSER array describing the GT Block timer.
 **/
 STATIC CONST ACPI_PARSER GtBlockTimerParser[] = {
-  {L"Frame Number", 1, 0, L"%d", NULL, NULL, NULL, NULL},
+  {L"Frame Number", 1, 0, L"%d", NULL, NULL, ValidateGtFrameNumber, NULL},
   {L"Reserved", 3, 1, L"%x %x %x", Dump3Chars, NULL, NULL, NULL},
   {L"Physical address (CntBaseX)", 8, 4, L"0x%lx", NULL, NULL, NULL, NULL},
   {L"Physical address (CntEL0BaseX)", 8, 12, L"0x%lx", NULL, NULL, NULL,
@@ -145,6 +160,34 @@ ValidateGtBlockTimerCount (
   }
 }

+/**
+  This function validates the GT Frame Number.
+
+  @param [in] Ptr     Pointer to the start of the field data.
+  @param [in] Context Pointer to context specific information e.g. this
+                      could be a pointer to the ACPI table header.
+**/
+STATIC
+VOID
+EFIAPI
+ValidateGtFrameNumber (
+  IN UINT8* Ptr,
+  IN VOID*  Context
+  )
+{
+  UINT32 FrameNumber;
+
+  FrameNumber = *(UINT8*)Ptr;
+
+  if (FrameNumber > 7) {
+    IncrementErrorCount ();
+    Print (
+      L"\nERROR: GT Frame Number = %d. GT Frame Number must be in range 0-7.",
+      FrameNumber
+      );
+  }
+}
+
 /**
   This function parses the Platform GT Block.

--
'Guid(CE165669-3EF3-493F-B85D-6190EE5B9759)'


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