From ec3809159997bb7cc39a746a9d17f8385866d2a2 Mon Sep 17 00:00:00 2001
From: vit9696 <vit9696@users.noreply.github.com>
Date: Mon, 7 May 2018 00:23:04 +0300
Subject: [PATCH] Improve descriptor version handling

---
 common/descriptor.h  | 17 +++++++----------
 common/ffsparser.cpp | 23 +++++++++++++++--------
 2 files changed, 22 insertions(+), 18 deletions(-)

diff --git a/common/descriptor.h b/common/descriptor.h
index aaf426c..dfca7fc 100644
--- a/common/descriptor.h
+++ b/common/descriptor.h
@@ -36,18 +36,15 @@ typedef struct FLASH_DESCRIPTOR_HEADER_ {
 
 // Descriptor version was reserved in older firmware
 #define FLASH_DESCRIPTOR_VERSION_INVALID 0xFFFFFFFF
+// The only known version found in Coffee Lake
+#define FLASH_DESCRIPTOR_VERSION_MAJOR   1
+#define FLASH_DESCRIPTOR_VERSION_MINOR   0
 
 // Descriptor version present in Coffee Lake and newer
-typedef struct _FLASH_DESCRIPTOR_VERSION_V3 {
+typedef struct _FLASH_DESCRIPTOR_VERSION {
     UINT32 Reserved : 14;
-    UINT32 VersionMinor : 7;
-    UINT32 VersionMajor : 11;
-} FLASH_DESCRIPTOR_VERSION_V3;
-
-// Descripror version
-typedef union _FLASH_DESCRIPTOR_VERSION {
-    UINT32 RawValue;
-    FLASH_DESCRIPTOR_VERSION_V3 V3;
+    UINT32 Minor : 7;
+    UINT32 Major : 11;
 } FLASH_DESCRIPTOR_VERSION;
 
 // Descriptor map
@@ -71,7 +68,7 @@ typedef struct FLASH_DESCRIPTOR_MAP_ {
     UINT32 NumberOfProcStraps : 8;      // One-based number of UINT32s to read as processor straps, min=0, max=255 (1 Kb)
     UINT32 : 16;
     // FLMAP 3
-    FLASH_DESCRIPTOR_VERSION Version;   // Reserved prior to v3
+    UINT32 DescriptorVersion;           // Reserved prior to Coffee Lake
 } FLASH_DESCRIPTOR_MAP;
 
 // Component section
diff --git a/common/ffsparser.cpp b/common/ffsparser.cpp
index 6776dc3..b87bc50 100644
--- a/common/ffsparser.cpp
+++ b/common/ffsparser.cpp
@@ -317,14 +317,10 @@ USTATUS FfsParser::parseIntelImage(const UByteArray & intelImage, const UINT32 l
     const FLASH_DESCRIPTOR_REGION_SECTION* regionSection = (const FLASH_DESCRIPTOR_REGION_SECTION*)calculateAddress8((UINT8*)descriptor, descriptorMap->RegionBase);
     const FLASH_DESCRIPTOR_COMPONENT_SECTION* componentSection = (const FLASH_DESCRIPTOR_COMPONENT_SECTION*)calculateAddress8((UINT8*)descriptor, descriptorMap->ComponentBase);
 
-    UINT8 descriptorVersion = 0;
-    if (descriptorMap->Version.RawValue != FLASH_DESCRIPTOR_VERSION_INVALID)                     // Kaby Lake+ descriptor
-        descriptorVersion = 3;
+    UINT8 descriptorVersion = 2;
     // Check descriptor version by getting hardcoded value of FlashParameters.ReadClockFrequency
-    else if (componentSection->FlashParameters.ReadClockFrequency == FLASH_FREQUENCY_20MHZ)      // Old descriptor
+    if (componentSection->FlashParameters.ReadClockFrequency == FLASH_FREQUENCY_20MHZ)
         descriptorVersion = 1;
-    else // Skylake+ descriptor
-        descriptorVersion = 2;
 
     // Regions
     std::vector<REGION_INFO> regions;
@@ -374,7 +370,7 @@ USTATUS FfsParser::parseIntelImage(const UByteArray & intelImage, const UINT32 l
     // Add all other regions
     for (UINT8 i = Subtypes::GbeRegion; i <= Subtypes::PttRegion; i++) {
         if (descriptorVersion == 1 && i == Subtypes::MicrocodeRegion)
-            break; // Do not parse Microcode and other following regions for old descriptors 
+            break; // Do not parse Microcode and other following regions for legacy descriptors
 
         const UINT16* RegionBase = ((const UINT16*)regionSection) + 2 * i;
         const UINT16* RegionLimit = ((const UINT16*)regionSection) + 2 * i + 1;
@@ -507,7 +503,7 @@ USTATUS FfsParser::parseIntelImage(const UByteArray & intelImage, const UINT32 l
         info += usprintf("\nPDR   %s  %s",  masterSection->BiosRead  & FLASH_DESCRIPTOR_REGION_ACCESS_PDR  ? "Yes " : "No  ",
                                             masterSection->BiosWrite & FLASH_DESCRIPTOR_REGION_ACCESS_PDR  ? "Yes " : "No  ");
     }
-    else if (descriptorVersion >= 2) {
+    else if (descriptorVersion == 2) {
         const FLASH_DESCRIPTOR_MASTER_SECTION_V2* masterSection = (const FLASH_DESCRIPTOR_MASTER_SECTION_V2*)calculateAddress8((UINT8*)descriptor, descriptorMap->MasterBase);
         info += UString("\nRegion access settings:");
         info += usprintf("\nBIOS: %03Xh %03Xh ME: %03Xh %03Xh\nGbE:  %03Xh %03Xh EC: %03Xh %03Xh",
@@ -539,6 +535,17 @@ USTATUS FfsParser::parseIntelImage(const UByteArray & intelImage, const UINT32 l
         info += usprintf("\nEC    %s  %s",
             masterSection->BiosRead  & FLASH_DESCRIPTOR_REGION_ACCESS_EC ? "Yes " : "No  ",
             masterSection->BiosWrite & FLASH_DESCRIPTOR_REGION_ACCESS_EC ? "Yes " : "No  ");
+
+        // Prepend descriptor version if present
+        if (descriptorMap->DescriptorVersion != FLASH_DESCRIPTOR_VERSION_INVALID) {
+            const FLASH_DESCRIPTOR_VERSION* version = (const FLASH_DESCRIPTOR_VERSION*)&descriptorMap->DescriptorVersion;
+            UString versionStr = usprintf("Flash descriptor version: %d.%d", version->Major, version->Minor);
+            if (version->Major != FLASH_DESCRIPTOR_VERSION_MAJOR || version->Minor != FLASH_DESCRIPTOR_VERSION_MINOR) {
+                versionStr += ", unknown";
+                msg(usprintf("%s: unknown flash descriptor version %d.%d", __FUNCTION__, version->Major, version->Minor));
+            }
+            info = versionStr + "\n" + info;
+        }
     }
 
     // VSCC table