[PATCH v2 1/1] ShellPkg: acpiview: Add support for parsing FACS

["Sami Mujawar" <sami.mujawar@arm.com>]

Add support for parsing the ACPI FACS table.

The FADT parser has also been updated as it
links the FACS table using the FIRMWARE_CTRL
or X_FIRMWARE_CTRL fields.

Since the FACS table does not follow the standard
ACPI header, the FADT parser extracts the FACS
signature, length and version fields before invoking
the FACS parser.

Cc: Ray Ni <ray.ni@intel.com>
Cc: Zhichao Gao <zhichao.gao@intel.com>
Signed-off-by: Sami Mujawar <sami.mujawar@arm.com>
---

The changes can be seen at:
https://github.com/samimujawar/edk2/tree/656_acpiview_facs_parser_v1

Notes:
    v2:
      - Fixed patch check failure in commit message,                [SAMI]
          changed 'CC' to 'Cc'. No code change.            
    v1:
     - Add support for parsing FACS table                           [SAMI]

 ShellPkg/Library/UefiShellAcpiViewCommandLib/AcpiParser.h                    | 21 +++++
 ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Facs/FacsParser.c       | 71 +++++++++++++++
 ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Fadt/FadtParser.c       | 90 ++++++++++++++++++--
 ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCommandLib.c   |  1 +
 ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCommandLib.inf |  1 +
 5 files changed, 179 insertions(+), 5 deletions(-)

diff --git a/ShellPkg/Library/UefiShellAcpiViewCommandLib/AcpiParser.h b/ShellPkg/Library/UefiShellAcpiViewCommandLib/AcpiParser.h
index 20ca358bddfa5953bfb1d1bebaebbf3079eaba01..f374f8ebfe313954c05b2a432816cf7ad3af9e32 100644
--- a/ShellPkg/Library/UefiShellAcpiViewCommandLib/AcpiParser.h
+++ b/ShellPkg/Library/UefiShellAcpiViewCommandLib/AcpiParser.h
@@ -528,6 +528,27 @@ ParseAcpiDsdt (
   IN UINT8   AcpiTableRevision
   );
 
+/**
+  This function parses the ACPI FACS table.
+  When trace is enabled this function parses the FACS table and
+  traces the ACPI table fields.
+
+  This function also performs validation of the ACPI table fields.
+
+  @param [in] Trace              If TRUE, trace the ACPI fields.
+  @param [in] Ptr                Pointer to the start of the buffer.
+  @param [in] AcpiTableLength    Length of the ACPI table.
+  @param [in] AcpiTableRevision  Revision of the ACPI table.
+**/
+VOID
+EFIAPI
+ParseAcpiFacs (
+  IN BOOLEAN Trace,
+  IN UINT8*  Ptr,
+  IN UINT32  AcpiTableLength,
+  IN UINT8   AcpiTableRevision
+  );
+
 /**
   This function parses the ACPI FADT table.
   This function parses the FADT table and optionally traces the ACPI
diff --git a/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Facs/FacsParser.c b/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Facs/FacsParser.c
new file mode 100644
index 0000000000000000000000000000000000000000..d6bea86bdbaa79aa35b86840c809394b3c7a3bf6
--- /dev/null
+++ b/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Facs/FacsParser.c
@@ -0,0 +1,71 @@
+/** @file
+  FACS table parser
+
+  Copyright (c) 2019, ARM Limited. All rights reserved.
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+  @par Reference(s):
+    - ACPI 6.3 Specification - January 2019
+**/
+
+#include <IndustryStandard/Acpi.h>
+#include <Library/UefiLib.h>
+#include "AcpiParser.h"
+#include "AcpiTableParser.h"
+
+/**
+  An ACPI_PARSER array describing the ACPI FACS Table.
+**/
+STATIC CONST ACPI_PARSER FacsParser[] = {
+  {L"Signature", 4, 0, L"%c%c%c%c", Dump4Chars, NULL, NULL, NULL},
+  {L"Length", 4, 4, L"%d", NULL,  NULL, NULL, NULL},
+  {L"Hardware Signature", 4, 8, L"0x%x", NULL, NULL, NULL, NULL},
+  {L"Firmware Waking Vector", 4, 12, L"0x%x", NULL, NULL, NULL, NULL},
+  {L"Global Lock", 4, 16, L"0x%x", NULL, NULL, NULL, NULL},
+  {L"Flags", 4, 20, L"0x%x", NULL, NULL, NULL, NULL},
+  {L"X Firmware Walking Vector", 8, 24, L"0x%lx", NULL, NULL, NULL, NULL},
+  {L"Version", 1, 32, L"%d", NULL, NULL, NULL, NULL},
+  {L"Reserved", 3, 33, L"%x %x %x", Dump3Chars, NULL, NULL, NULL},
+  {L"OSPM Flags", 4, 36, L"0x%x", NULL, NULL, NULL, NULL},
+  {L"Reserved", 8, 40, L"%x %x %x %x %x %x %x %x", Dump8Chars, NULL, NULL,
+    NULL},
+  {L"Reserved", 8, 48, L"%x %x %x %x %x %x %x %x", Dump8Chars, NULL, NULL,
+    NULL},
+  {L"Reserved", 8, 56, L"%x %x %x %x %x %x %x %x", Dump8Chars, NULL, NULL,
+    NULL}
+};
+
+/**
+  This function parses the ACPI FACS table.
+  When trace is enabled this function parses the FACS table and
+  traces the ACPI table fields.
+
+  This function also performs validation of the ACPI table fields.
+
+  @param [in] Trace              If TRUE, trace the ACPI fields.
+  @param [in] Ptr                Pointer to the start of the buffer.
+  @param [in] AcpiTableLength    Length of the ACPI table.
+  @param [in] AcpiTableRevision  Revision of the ACPI table.
+**/
+VOID
+EFIAPI
+ParseAcpiFacs (
+  IN BOOLEAN Trace,
+  IN UINT8*  Ptr,
+  IN UINT32  AcpiTableLength,
+  IN UINT8   AcpiTableRevision
+  )
+{
+  if (!Trace) {
+    return;
+  }
+
+  ParseAcpi (
+    Trace,
+    0,
+    "FACS",
+    Ptr,
+    AcpiTableLength,
+    PARSER_PARAMS (FacsParser)
+    );
+}
diff --git a/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Fadt/FadtParser.c b/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Fadt/FadtParser.c
index e40c9ef8ee4b3285faf8c6edf3cb6236ee367397..5b8cc174f16afb3d4feb6a518952e60c6564ee34 100644
--- a/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Fadt/FadtParser.c
+++ b/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Fadt/FadtParser.c
@@ -5,17 +5,21 @@
   SPDX-License-Identifier: BSD-2-Clause-Patent
 
   @par Reference(s):
-    - ACPI 6.2 Specification - Errata A, September 2017
+    - ACPI 6.3 Specification - January 2019
 **/
 
 #include <IndustryStandard/Acpi.h>
 #include <Library/UefiLib.h>
 #include "AcpiParser.h"
 #include "AcpiTableParser.h"
+#include "AcpiView.h"
 
 // Local variables
 STATIC CONST UINT32* DsdtAddress;
 STATIC CONST UINT64* X_DsdtAddress;
+STATIC CONST UINT32* Flags;
+STATIC CONST UINT32* FirmwareCtrl;
+STATIC CONST UINT64* X_FirmwareCtrl;
 STATIC CONST UINT8*  FadtMinorRevision;
 STATIC ACPI_DESCRIPTION_HEADER_INFO AcpiHdrInfo;
 
@@ -24,6 +28,21 @@ STATIC ACPI_DESCRIPTION_HEADER_INFO AcpiHdrInfo;
 **/
 #define HW_REDUCED_ACPI   BIT20
 
+/**
+  Offset to the FACS signature from the start of the FACS.
+**/
+#define FACS_SIGNATURE_OFFSET   0
+
+/**
+  Offset to the FACS revision from the start of the FACS.
+**/
+#define FACS_VERSION_OFFSET     32
+
+/**
+  Offset to the FACS length from the start of the FACS.
+**/
+#define FACS_LENGTH_OFFSET      4
+
 /**
   Get the ACPI XSDT header info.
 **/
@@ -113,7 +132,8 @@ ValidateFlags (
 **/
 STATIC CONST ACPI_PARSER FadtParser[] = {
   PARSE_ACPI_HEADER (&AcpiHdrInfo),
-  {L"FIRMWARE_CTRL", 4, 36, L"0x%x", NULL, NULL, ValidateFirmwareCtrl, NULL},
+  {L"FIRMWARE_CTRL", 4, 36, L"0x%x", NULL, (VOID**)&FirmwareCtrl,
+    ValidateFirmwareCtrl, NULL},
   {L"DSDT", 4, 40, L"0x%x", NULL, (VOID**)&DsdtAddress, NULL, NULL},
   {L"Reserved", 1, 44, L"%x", NULL, NULL, NULL, NULL},
   {L"Preferred_PM_Profile", 1, 45, L"0x%x", NULL, NULL, NULL, NULL},
@@ -150,13 +170,13 @@ STATIC CONST ACPI_PARSER FadtParser[] = {
   {L"CENTURY", 1, 108, L"0x%x", NULL, NULL, NULL, NULL},
   {L"IAPC_BOOT_ARCH", 2, 109, L"0x%x", NULL, NULL, NULL, NULL},
   {L"Reserved", 1, 111, L"0x%x", NULL, NULL, NULL, NULL},
-  {L"Flags", 4, 112, L"0x%x", NULL, NULL, ValidateFlags, NULL},
+  {L"Flags", 4, 112, L"0x%x", NULL, (VOID**)&Flags, ValidateFlags, NULL},
   {L"RESET_REG", 12, 116, NULL, DumpGas, NULL, NULL, NULL},
   {L"RESET_VALUE", 1, 128, L"0x%x", NULL, NULL, NULL, NULL},
   {L"ARM_BOOT_ARCH", 2, 129, L"0x%x", NULL, NULL, NULL, NULL},
   {L"FADT Minor Version", 1, 131, L"0x%x", NULL, (VOID**)&FadtMinorRevision,
     NULL, NULL},
-  {L"X_FIRMWARE_CTRL", 8, 132, L"0x%lx", NULL, NULL,
+  {L"X_FIRMWARE_CTRL", 8, 132, L"0x%lx", NULL, (VOID**)&X_FirmwareCtrl,
     ValidateXFirmwareCtrl, NULL},
   {L"X_DSDT", 8, 140, L"0x%lx", NULL, (VOID**)&X_DsdtAddress, NULL, NULL},
   {L"X_PM1a_EVT_BLK", 12, 148, NULL, DumpGas, NULL, NULL, NULL},
@@ -192,7 +212,13 @@ ParseAcpiFadt (
   IN UINT8   AcpiTableRevision
   )
 {
-  UINT8*  DsdtPtr;
+  EFI_STATUS              Status;
+  UINT8*                  DsdtPtr;
+  UINT8*                  FirmwareCtrlPtr;
+  UINT32                  FacsSignature;
+  UINT32                  FacsLength;
+  UINT8                   FacsRevision;
+  PARSE_ACPI_TABLE_PROC   FacsParserProc;
 
   ParseAcpi (
     Trace,
@@ -214,6 +240,60 @@ ParseAcpiFadt (
     }
   }
 
+  // If X_FIRMWARE_CTRL is not zero then use X_FIRMWARE_CTRL and ignore
+  // FIRMWARE_CTRL, else use FIRMWARE_CTRL.
+  if ((X_FirmwareCtrl != NULL) && (*X_FirmwareCtrl != 0)) {
+    FirmwareCtrlPtr = (UINT8*)(UINTN)(*X_FirmwareCtrl);
+  } else if ((FirmwareCtrl != NULL) && (*FirmwareCtrl != 0)) {
+    FirmwareCtrlPtr = (UINT8*)(UINTN)(*FirmwareCtrl);
+  } else {
+    FirmwareCtrlPtr = NULL;
+    // if HW_REDUCED_ACPI flag is not set, both FIRMWARE_CTRL and
+    // X_FIRMWARE_CTRL cannot be zero, and the FACS Table must be
+    // present.
+    if ((Trace) &&
+        (Flags != NULL) &&
+        ((*Flags & EFI_ACPI_6_3_HW_REDUCED_ACPI) != 0)) {
+      IncrementErrorCount ();
+      Print (L"ERROR: No FACS table found, "
+               L"both X_FIRMWARE_CTRL and FIRMWARE_CTRL are zero.\n");
+    }
+  }
+
+  if (FirmwareCtrlPtr != NULL) {
+    // The FACS table does not have a standard ACPI table header. Therefore,
+    // the signature, length and version needs to be initially parsed.
+    // The FACS signature is 4 bytes starting at offset 0.
+    FacsSignature = *(UINT32*)(FirmwareCtrlPtr + FACS_SIGNATURE_OFFSET);
+
+    // The FACS length is 4 bytes starting at offset 4.
+    FacsLength = *(UINT32*)(FirmwareCtrlPtr + FACS_LENGTH_OFFSET);
+
+    // The FACS version is 1 byte starting at offset 32.
+    FacsRevision = *(UINT8*)(FirmwareCtrlPtr + FACS_VERSION_OFFSET);
+
+    Trace = ProcessTableReportOptions (
+              FacsSignature,
+              FirmwareCtrlPtr,
+              FacsLength
+              );
+
+    Status = GetParser (FacsSignature, &FacsParserProc);
+    if (EFI_ERROR (Status)) {
+      Print (
+        L"ERROR: No registered parser found for FACS.\n"
+        );
+      return;
+    }
+
+    FacsParserProc (
+      Trace,
+      FirmwareCtrlPtr,
+      FacsLength,
+      FacsRevision
+      );
+  }
+
   // If X_DSDT is not zero then use X_DSDT and ignore DSDT,
   // else use DSDT.
   if (*X_DsdtAddress != 0) {
diff --git a/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCommandLib.c b/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCommandLib.c
index 3ee0f0fe421c6acdde33becca80d8efcbeda0fde..e0d5a81085525a91110d9a25279adf3376286342 100644
--- a/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCommandLib.c
+++ b/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCommandLib.c
@@ -29,6 +29,7 @@ ACPI_TABLE_PARSER ParserList[] = {
   {EFI_ACPI_6_2_DEBUG_PORT_2_TABLE_SIGNATURE, ParseAcpiDbg2},
   {EFI_ACPI_6_2_DIFFERENTIATED_SYSTEM_DESCRIPTION_TABLE_SIGNATURE,
    ParseAcpiDsdt},
+  {EFI_ACPI_6_3_FIRMWARE_ACPI_CONTROL_STRUCTURE_SIGNATURE, ParseAcpiFacs},
   {EFI_ACPI_6_2_FIXED_ACPI_DESCRIPTION_TABLE_SIGNATURE, ParseAcpiFadt},
   {EFI_ACPI_6_2_GENERIC_TIMER_DESCRIPTION_TABLE_SIGNATURE, ParseAcpiGtdt},
   {EFI_ACPI_6_2_IO_REMAPPING_TABLE_SIGNATURE, ParseAcpiIort},
diff --git a/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCommandLib.inf b/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCommandLib.inf
index 1e2fa52b00a37f73d789ba4049c531f5bc29fb5b..ea504c934aeebaa452a380e6ea169586e467642a 100644
--- a/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCommandLib.inf
+++ b/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCommandLib.inf
@@ -31,6 +31,7 @@ [Sources.common]
   Parsers/Bgrt/BgrtParser.c
   Parsers/Dbg2/Dbg2Parser.c
   Parsers/Dsdt/DsdtParser.c
+  Parsers/Facs/FacsParser.c
   Parsers/Fadt/FadtParser.c
   Parsers/Gtdt/GtdtParser.c
   Parsers/Iort/IortParser.c
-- 
'Guid(CE165669-3EF3-493F-B85D-6190EE5B9759)'