ArmPkg: Drop PcdNormalMemoryNonshareableOverride support

There are no upstream platforms sets this Pcd, this Pcd was
introduced by ArmVExpress-CTA15-A7.

Signed-off-by: Ajan Zhong <ajan.zhong@newfw.com>

4 files changed, 10 insertions, 72 deletions

diff --git a/ArmPkg/ArmPkg.dec b/ArmPkg/ArmPkg.dec
index b528bb4..04252da 100644
--- a/ArmPkg/ArmPkg.dec
+++ b/ArmPkg/ArmPkg.dec
@@ -115,12 +115,6 @@
   # attributes initially, and can be disabled otherwise.

   gArmTokenSpaceGuid.PcdRemapUnusedMemoryNx|TRUE|BOOLEAN|0x00000048

 

-[PcdsFeatureFlag.ARM]

-  # Whether to map normal memory as non-shareable. FALSE is the safe choice, but

-  # TRUE may be appropriate to fix performance problems if you don't care about

-  # hardware coherency (i.e., no virtualization or cache coherent DMA)

-  gArmTokenSpaceGuid.PcdNormalMemoryNonshareableOverride|FALSE|BOOLEAN|0x00000043

-

 [PcdsFixedAtBuild.common]

   gArmTokenSpaceGuid.PcdTrustzoneSupport|FALSE|BOOLEAN|0x00000006

 

diff --git a/ArmPkg/Library/ArmLib/ArmBaseLib.inf b/ArmPkg/Library/ArmLib/ArmBaseLib.inf
index e37d85b..6d1acd2 100644
--- a/ArmPkg/Library/ArmLib/ArmBaseLib.inf
+++ b/ArmPkg/Library/ArmLib/ArmBaseLib.inf
@@ -45,6 +45,3 @@
 [Packages]

   ArmPkg/ArmPkg.dec

   MdePkg/MdePkg.dec

-

-[FeaturePcd.ARM]

-  gArmTokenSpaceGuid.PcdNormalMemoryNonshareableOverride

diff --git a/ArmPkg/Library/ArmMmuLib/Arm/ArmMmuLibCore.c b/ArmPkg/Library/ArmMmuLib/Arm/ArmMmuLibCore.c
index 60dc6c9..643541d 100644
--- a/ArmPkg/Library/ArmMmuLib/Arm/ArmMmuLibCore.c
+++ b/ArmPkg/Library/ArmMmuLib/Arm/ArmMmuLibCore.c
@@ -44,43 +44,6 @@ ArmHasMpExtensions (
   );

 

 STATIC

-BOOLEAN

-PreferNonshareableMemory (

-  VOID

-  )

-{

-  UINTN  Mmfr;

-  UINTN  Val;

-

-  if (FeaturePcdGet (PcdNormalMemoryNonshareableOverride)) {

-    return TRUE;

-  }

-

-  //

-  // Check whether the innermost level of shareability (the level we will use

-  // by default to map normal memory) is implemented with hardware coherency

-  // support. Otherwise, revert to mapping as non-shareable.

-  //

-  Mmfr = ArmReadIdMmfr0 ();

-  switch ((Mmfr >> ID_MMFR0_SHARELVL_SHIFT) & ID_MMFR0_SHARELVL_MASK) {

-    case ID_MMFR0_SHARELVL_ONE:

-      // one level of shareability

-      Val = (Mmfr >> ID_MMFR0_OUTERSHR_SHIFT) & ID_MMFR0_OUTERSHR_MASK;

-      break;

-    case ID_MMFR0_SHARELVL_TWO:

-      // two levels of shareability

-      Val = (Mmfr >> ID_MMFR0_INNERSHR_SHIFT) & ID_MMFR0_INNERSHR_MASK;

-      break;

-    default:

-      // unexpected value -> shareable is the safe option

-      ASSERT (FALSE);

-      return FALSE;

-  }

-

-  return Val != ID_MMFR0_SHR_IMP_HW_COHERENT;

-}

-

-STATIC

 VOID

 PopulateLevel2PageTable (

   IN UINT32                        *SectionEntry,

@@ -128,10 +91,6 @@ PopulateLevel2PageTable (
       break;

   }

 

-  if (PreferNonshareableMemory ()) {

-    PageAttributes &= ~TT_DESCRIPTOR_PAGE_S_SHARED;

-  }

-

   // Check if the Section Entry has already been populated. Otherwise attach a

   // Level 2 Translation Table to it

   if (*SectionEntry != 0) {

@@ -268,10 +227,6 @@ FillTranslationTable (
       break;

   }

 

-  if (PreferNonshareableMemory ()) {

-    Attributes &= ~TT_DESCRIPTOR_SECTION_S_SHARED;

-  }

-

   // Get the first section entry for this mapping

   SectionEntry = TRANSLATION_TABLE_ENTRY_FOR_VIRTUAL_ADDRESS (TranslationTable, MemoryRegion->VirtualBase);

 

@@ -370,21 +325,16 @@ ArmConfigureMmu (
 

   TTBRAttributes = ArmHasMpExtensions () ? TTBR_MP_WRITE_BACK_ALLOC

                                          : TTBR_WRITE_BACK_ALLOC;

-  if (TTBRAttributes & TTBR_SHAREABLE) {

-    if (PreferNonshareableMemory ()) {

-      TTBRAttributes ^= TTBR_SHAREABLE;

-    } else {

-      //

-      // Unlike the S bit in the short descriptors, which implies inner shareable

-      // on an implementation that supports two levels, the meaning of the S bit

-      // in the TTBR depends on the NOS bit, which defaults to Outer Shareable.

-      // However, we should only set this bit after we have confirmed that the

-      // implementation supports multiple levels, or else the NOS bit is UNK/SBZP

-      //

-      if (((ArmReadIdMmfr0 () >> 12) & 0xf) != 0) {

-        TTBRAttributes |= TTBR_NOT_OUTER_SHAREABLE;

-      }

-    }

+

+  //

+  // Unlike the S bit in the short descriptors, which implies inner shareable

+  // on an implementation that supports two levels, the meaning of the S bit

+  // in the TTBR depends on the NOS bit, which defaults to Outer Shareable.

+  // However, we should only set this bit after we have confirmed that the

+  // implementation supports multiple levels, or else the NOS bit is UNK/SBZP

+  //

+  if (((ArmReadIdMmfr0 () >> 12) & 0xf) != 0) {

+    TTBRAttributes |= TTBR_NOT_OUTER_SHAREABLE;

   }

 

   ArmSetTTBR0 ((VOID *)((UINTN)TranslationTable | TTBRAttributes));

diff --git a/ArmPkg/Library/ArmMmuLib/ArmMmuBaseLib.inf b/ArmPkg/Library/ArmMmuLib/ArmMmuBaseLib.inf
index 5ee4afa..1a9552b 100644
--- a/ArmPkg/Library/ArmMmuLib/ArmMmuBaseLib.inf
+++ b/ArmPkg/Library/ArmMmuLib/ArmMmuBaseLib.inf
@@ -44,6 +44,3 @@
 

 [Guids]

   gArmMmuReplaceLiveTranslationEntryFuncGuid

-

-[Pcd.ARM]

-  gArmTokenSpaceGuid.PcdNormalMemoryNonshareableOverride