From f28d3cfe0ae44462634fe2271469919b861f79ca Mon Sep 17 00:00:00 2001
From: Zhuowei Zhang <zhuoweizhang@yahoo.com>
Date: Fri, 22 Feb 2019 20:35:49 -0800
Subject: [PATCH] Mark in memory serial zone as uncached

---
 .../InMemorySerialPortLib.c                   |  2 +
 Pixel3XL/Library/Pixel3XLLib/Pixel3XLMem.c    | 43 +++++++++++++++----
 2 files changed, 37 insertions(+), 8 deletions(-)

diff --git a/Pixel3XL/Library/InMemorySerialPortLib/InMemorySerialPortLib.c b/Pixel3XL/Library/InMemorySerialPortLib/InMemorySerialPortLib.c
index 542b1db..467f350 100644
--- a/Pixel3XL/Library/InMemorySerialPortLib/InMemorySerialPortLib.c
+++ b/Pixel3XL/Library/InMemorySerialPortLib/InMemorySerialPortLib.c
@@ -33,10 +33,12 @@ SerialPortInitialize (
   VOID
   )
 {
+#if 0
   UINT8* base = (UINT8*)0xa1a10000ull;
   for (UINTN i = 0; i < 0x200000; i++) {
     base[i] = 0;
   }
+#endif
   return RETURN_SUCCESS;
 }
 
diff --git a/Pixel3XL/Library/Pixel3XLLib/Pixel3XLMem.c b/Pixel3XL/Library/Pixel3XLLib/Pixel3XLMem.c
index 99cbaec..c292e08 100644
--- a/Pixel3XL/Library/Pixel3XLLib/Pixel3XLMem.c
+++ b/Pixel3XL/Library/Pixel3XLLib/Pixel3XLMem.c
@@ -31,10 +31,16 @@
 
 #define HIKEY960_MEMORY_SIZE               0x0000000100000000
 
+
+// A compromise between the original HiKey960's reserved memory code and Lumia950XLPkg's massive tables
 STATIC struct Pixel3XLReservedMemory {
   EFI_PHYSICAL_ADDRESS         Offset;
   EFI_PHYSICAL_ADDRESS         Size;
+  EFI_RESOURCE_ATTRIBUTE_TYPE  Attributes;
+  ARM_MEMORY_REGION_ATTRIBUTES MemoryTableAttributes;
 } Pixel3XLReservedMemoryBuffer [] = {
+  { 0x9d400000, 0x02400000, EFI_RESOURCE_ATTRIBUTE_WRITE_THROUGH_CACHEABLE, ARM_MEMORY_REGION_ATTRIBUTE_WRITE_THROUGH},
+  { 0xa1a10000, 0x00200000, EFI_RESOURCE_ATTRIBUTE_UNCACHEABLE, ARM_MEMORY_REGION_ATTRIBUTE_UNCACHED_UNBUFFERED},
 /*
   { 0x1AC00000, 0x00098000 },    // ARM-TF reserved
   { 0x32000000, 0x00100000 },    // PSTORE/RAMOOPS
@@ -104,7 +110,7 @@ ArmPlatformGetVirtualMemoryMap (
       // Create the System Memory HOB for the reserved buffer
       BuildResourceDescriptorHob (
         EFI_RESOURCE_MEMORY_RESERVED,
-        EFI_RESOURCE_ATTRIBUTE_PRESENT,
+        Pixel3XLReservedMemoryBuffer[Index].Attributes,
         Pixel3XLReservedMemoryBuffer[Index].Offset,
         Pixel3XLReservedMemoryBuffer[Index].Size
       );
@@ -138,18 +144,39 @@ ArmPlatformGetVirtualMemoryMap (
 
   Index = 0;
 
-  // DDR - 4.0GB section
-  VirtualMemoryTable[Index].PhysicalBase    = PcdGet64 (PcdSystemMemoryBase);
-  VirtualMemoryTable[Index].VirtualBase     = PcdGet64 (PcdSystemMemoryBase);
-  VirtualMemoryTable[Index].Length          = PcdGet64 (PcdSystemMemorySize);
-  VirtualMemoryTable[Index].Attributes      = CacheAttributes;
-
   // SDM845 SOC peripherals
-  VirtualMemoryTable[++Index].PhysicalBase  = SDM845_PERIPH_BASE;
+  VirtualMemoryTable[Index].PhysicalBase    = SDM845_PERIPH_BASE;
   VirtualMemoryTable[Index].VirtualBase     = SDM845_PERIPH_BASE;
   VirtualMemoryTable[Index].Length          = SDM845_PERIPH_SZ;
   VirtualMemoryTable[Index].Attributes      = ARM_MEMORY_REGION_ATTRIBUTE_DEVICE;
 
+  EFI_PHYSICAL_ADDRESS RamBase = PcdGet64 (PcdSystemMemoryBase); 
+
+  // Honestly, I should probably just copypasta Lumia950XLPkg's table.
+  // Oh well.
+  for (unsigned int reserveI = 0; reserveI < Count; reserveI++) {
+    UINTN lastNonReservedBlockEnd = Pixel3XLReservedMemoryBuffer[reserveI].Offset;
+    if (lastNonReservedBlockEnd > RamBase) {
+      VirtualMemoryTable[Index++].PhysicalBase = RamBase;
+      VirtualMemoryTable[Index].VirtualBase = RamBase;
+      VirtualMemoryTable[Index].Length = lastNonReservedBlockEnd - RamBase;
+      VirtualMemoryTable[Index].Attributes = CacheAttributes;
+    }
+    VirtualMemoryTable[Index++].PhysicalBase = lastNonReservedBlockEnd;
+    VirtualMemoryTable[Index].VirtualBase = lastNonReservedBlockEnd;
+    VirtualMemoryTable[Index].Length = Pixel3XLReservedMemoryBuffer[reserveI].Size;
+    VirtualMemoryTable[Index].Attributes = Pixel3XLReservedMemoryBuffer[reserveI].MemoryTableAttributes;
+    RamBase = lastNonReservedBlockEnd + Pixel3XLReservedMemoryBuffer[reserveI].Size;
+  }
+
+  EFI_PHYSICAL_ADDRESS EndOfMemory = PcdGet64 (PcdSystemMemoryBase) + PcdGet64 (PcdSystemMemorySize);
+  if (EndOfMemory > RamBase) {
+    VirtualMemoryTable[Index++].PhysicalBase = RamBase;
+    VirtualMemoryTable[Index].VirtualBase = RamBase;
+    VirtualMemoryTable[Index].Length = EndOfMemory - RamBase;
+    VirtualMemoryTable[Index].Attributes = CacheAttributes;
+  }
+
   // End of Table
   VirtualMemoryTable[++Index].PhysicalBase  = 0;
   VirtualMemoryTable[Index].VirtualBase     = 0;