[PATCH 18/19] ArmPlatformPkg: Reserving framebuffer at build

[evan.lloyd@arm.com]

From: Girish Pathak <girish.pathak@arm.com>

Currently frame buffer memory is either reserved in special VRAM or
dynamically allocated using boot services memory allocation functions.
When allocated using boot services calls the memory has to be allocated
as EfiBootServicesData. Unfortunately failures have been seen with this
case.  There is also an unfortunate lack of control on the placement of
the frmae buffer.

This change introduces two PCDs, PcdArmLcdFrameBufferBase and
PcdArmLcdFrameBufferSize which enable build time reservation of the
frame buffer, avoiding the need to allocate dynamically.  This allows
the frame buffer to appear as "I/O memory" outside of the normal RAM
map, which is similar to the "VRAM" case.

This change has no impact on current code, only enables the option
of build time reservation of frame buffers.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Girish Pathak <girish.pathak@arm.com>
Signed-off-by: Evan Lloyd <evan.lloyd@arm.com>
---
 ArmPlatformPkg/ArmPlatformPkg.dec                                           |  4 ++++
 ArmPlatformPkg/ArmVExpressPkg/Library/ArmVExpressLibRTSM/ArmVExpressLib.inf |  4 +++-
 ArmPlatformPkg/ArmVExpressPkg/Library/ArmVExpressLibRTSM/RTSMMem.c          | 21 ++++++++++++++++++--
 3 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/ArmPlatformPkg/ArmPlatformPkg.dec b/ArmPlatformPkg/ArmPlatformPkg.dec
index 77eb789ad8fe4ddcbf25abefad2e7b7d3d5e1722..0174f63e77f5b8430e106289366feb9a6577fb99 100644
--- a/ArmPlatformPkg/ArmPlatformPkg.dec
+++ b/ArmPlatformPkg/ArmPlatformPkg.dec
@@ -111,6 +111,10 @@ [PcdsFixedAtBuild.common]
   gArmPlatformTokenSpaceGuid.PcdPL111LcdBase|0x0|UINT32|0x00000026
   gArmPlatformTokenSpaceGuid.PcdArmHdLcdBase|0x0|UINT32|0x00000027
 
+  ## If set, frame buffer memory will be reserved and mapped in the system RAM
+  gArmPlatformTokenSpaceGuid.PcdArmLcdDdrFrameBufferSize|0x0|UINT32|0x00000033
+  gArmPlatformTokenSpaceGuid.PcdArmLcdDdrFrameBufferBase|0x0|UINT64|0x00000034
+
   ## PL180 MCI
   gArmPlatformTokenSpaceGuid.PcdPL180SysMciRegAddress|0x00000000|UINT32|0x00000028
   gArmPlatformTokenSpaceGuid.PcdPL180MciBaseAddress|0x00000000|UINT32|0x00000029
diff --git a/ArmPlatformPkg/ArmVExpressPkg/Library/ArmVExpressLibRTSM/ArmVExpressLib.inf b/ArmPlatformPkg/ArmVExpressPkg/Library/ArmVExpressLibRTSM/ArmVExpressLib.inf
index 9b16f7f0c4731ab72bfb1008a073e81842bae82b..60789e9b8ff1b936db04953a765fb164b0e85a40 100644
--- a/ArmPlatformPkg/ArmVExpressPkg/Library/ArmVExpressLibRTSM/ArmVExpressLib.inf
+++ b/ArmPlatformPkg/ArmVExpressPkg/Library/ArmVExpressLibRTSM/ArmVExpressLib.inf
@@ -1,5 +1,5 @@
 #/* @file
-#  Copyright (c) 2011-2014, ARM Limited. All rights reserved.
+#  Copyright (c) 2011-2017, ARM Limited. All rights reserved.
 #
 #  This program and the accompanying materials
 #  are licensed and made available under the terms and conditions of the BSD License
@@ -57,6 +57,8 @@ [FixedPcd]
   gArmTokenSpaceGuid.PcdArmPrimaryCore
 
   gArmPlatformTokenSpaceGuid.PcdCoreCount
+  gArmPlatformTokenSpaceGuid.PcdArmLcdDdrFrameBufferBase
+  gArmPlatformTokenSpaceGuid.PcdArmLcdDdrFrameBufferSize
 
 [Ppis]
   gArmMpCoreInfoPpiGuid
diff --git a/ArmPlatformPkg/ArmVExpressPkg/Library/ArmVExpressLibRTSM/RTSMMem.c b/ArmPlatformPkg/ArmVExpressPkg/Library/ArmVExpressLibRTSM/RTSMMem.c
index 6379e81751fca5e7972c5c30f305be65fd1ae71d..5cd529750a3d2d3b0d381b58d875d378afaba2c2 100644
--- a/ArmPlatformPkg/ArmVExpressPkg/Library/ArmVExpressLibRTSM/RTSMMem.c
+++ b/ArmPlatformPkg/ArmVExpressPkg/Library/ArmVExpressLibRTSM/RTSMMem.c
@@ -1,6 +1,6 @@
 /** @file
 *
-*  Copyright (c) 2011-2016, ARM Limited. All rights reserved.
+*  Copyright (c) 2011-2017, ARM Limited. All rights reserved.
 *
 *  This program and the accompanying materials
 *  are licensed and made available under the terms and conditions of the BSD License
@@ -20,8 +20,10 @@
 #include <Library/MemoryAllocationLib.h>
 #include <ArmPlatform.h>
 
+#define FRAME_BUFFER_DESCRIPTOR ((FixedPcdGet64 (PcdArmLcdDdrFrameBufferBase) != 0) ? 1 : 0)
+
 // Number of Virtual Memory Map Descriptors
-#define MAX_VIRTUAL_MEMORY_MAP_DESCRIPTORS          9
+#define MAX_VIRTUAL_MEMORY_MAP_DESCRIPTORS (9 + FRAME_BUFFER_DESCRIPTOR)
 
 // DDR attributes
 #define DDR_ATTRIBUTES_CACHED   ARM_MEMORY_REGION_ATTRIBUTE_WRITE_BACK
@@ -142,6 +144,21 @@ ArmPlatformGetVirtualMemoryMap (
   //
   VirtualMemoryTable[Index].Attributes = ARM_MEMORY_REGION_ATTRIBUTE_UNCACHED_UNBUFFERED;
 
+  // Map region for the frame buffer in the system RAM
+#if (FixedPcdGet32 (PcdArmLcdDdrFrameBufferSize) != 0)
+  VirtualMemoryTable[++Index].PhysicalBase = FixedPcdGet64 (PcdArmLcdDdrFrameBufferBase);
+  VirtualMemoryTable[Index].VirtualBase = FixedPcdGet64 (PcdArmLcdDdrFrameBufferBase);
+  VirtualMemoryTable[Index].Length = FixedPcdGet32 (PcdArmLcdDdrFrameBufferSize);
+  /* Map as Normal Non-Cacheable memory, so that we can use the accelerated
+   * SetMem/CopyMem routines that may use unaligned accesses or
+   * DC ZVA instructions. If mapped as device memory, these routine may cause
+   * alignment faults.
+   * NOTE: The attribute value is misleading, it indicates memory map type as
+   * an un-cached, un-buffered but allows buffering and reordering.
+   */
+  VirtualMemoryTable[Index].Attributes = ARM_MEMORY_REGION_ATTRIBUTE_UNCACHED_UNBUFFERED;
+#endif
+
   // Map sparse memory region if present
   if (HasSparseMemory) {
     VirtualMemoryTable[++Index].PhysicalBase = SparseMemoryBase;
-- 
Guid("CE165669-3EF3-493F-B85D-6190EE5B9759")