From 0a6d41ba0a080ff40620ff304fa9c99bb2874570 Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ardb@kernel.org>
Date: Thu, 1 Aug 2024 12:22:44 +0200
Subject: [PATCH] ArmPlatformPkg/ArmPlatformLib: Drop unused MPCore routines

Some of the boilerplate in ArmPlatformLib is only relevant when entering
UEFI on multiple cores, and this is no longer supported. So retire the
associated helper routines.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 .../Include/Library/ArmPlatformLib.h          | 43 -------------------
 .../AArch64/ArmPlatformHelper.S               | 33 --------------
 .../Arm/ArmPlatformHelper.S                   | 31 -------------
 .../ArmPlatformLibNull/ArmPlatformLibNull.c   |  4 --
 4 files changed, 111 deletions(-)

diff --git a/ArmPlatformPkg/Include/Library/ArmPlatformLib.h b/ArmPlatformPkg/Include/Library/ArmPlatformLib.h
index cd87743eba..38e7bdaf58 100644
--- a/ArmPlatformPkg/Include/Library/ArmPlatformLib.h
+++ b/ArmPlatformPkg/Include/Library/ArmPlatformLib.h
@@ -21,49 +21,6 @@
 
 #include <Library/ArmLib.h>
 
-/**
-  Return the core position from the value of its MpId register
-
-  This function returns the core position from the position 0 in the processor.
-  This function might be called from assembler before any stack is set.
-
-  @return   Return the core position
-
-**/
-UINTN
-ArmPlatformGetCorePosition (
-  IN UINTN  MpId
-  );
-
-/**
-  Return a non-zero value if the callee is the primary core
-
-  This function returns a non-zero value if the callee is the primary core.
-  The primary core is the core responsible to initialize the hardware and run UEFI.
-  This function might be called from assembler before any stack is set.
-
-  @return   Return a non-zero value if the callee is the primary core.
-
-**/
-UINTN
-ArmPlatformIsPrimaryCore (
-  IN UINTN  MpId
-  );
-
-/**
-  Return the MpId of the primary core
-
-  This function returns the MpId of the primary core.
-  This function might be called from assembler before any stack is set.
-
-  @return   Return the MpId of the primary core
-
-**/
-UINTN
-ArmPlatformGetPrimaryCoreMpId (
-  VOID
-  );
-
 /**
   Return the current Boot Mode
 
diff --git a/ArmPlatformPkg/Library/ArmPlatformLibNull/AArch64/ArmPlatformHelper.S b/ArmPlatformPkg/Library/ArmPlatformLibNull/AArch64/ArmPlatformHelper.S
index b7c6dbdc2e..1eeb7fed6f 100644
--- a/ArmPlatformPkg/Library/ArmPlatformLibNull/AArch64/ArmPlatformHelper.S
+++ b/ArmPlatformPkg/Library/ArmPlatformLibNull/AArch64/ArmPlatformHelper.S
@@ -10,36 +10,3 @@
 
 ASM_FUNC(ArmPlatformPeiBootAction)
   ret
-
-//UINTN
-//ArmPlatformGetCorePosition (
-//  IN UINTN MpId
-//  );
-// With this function: CorePos = (ClusterId * 4) + CoreId
-ASM_FUNC(ArmPlatformGetCorePosition)
-  and   x1, x0, #ARM_CORE_MASK
-  and   x0, x0, #ARM_CLUSTER_MASK
-  add   x0, x1, x0, LSR #6
-  ret
-
-//UINTN
-//ArmPlatformGetPrimaryCoreMpId (
-//  VOID
-//  );
-ASM_FUNC(ArmPlatformGetPrimaryCoreMpId)
-  MOV32  (w0, FixedPcdGet32 (PcdArmPrimaryCore))
-  ret
-
-//UINTN
-//ArmPlatformIsPrimaryCore (
-//  IN UINTN MpId
-//  );
-ASM_FUNC(ArmPlatformIsPrimaryCore)
-  MOV32  (w1, FixedPcdGet32 (PcdArmPrimaryCoreMask))
-  and   x0, x0, x1
-  MOV32  (w1, FixedPcdGet32 (PcdArmPrimaryCore))
-  cmp   w0, w1
-  mov   x0, #1
-  mov   x1, #0
-  csel  x0, x0, x1, eq
-  ret
diff --git a/ArmPlatformPkg/Library/ArmPlatformLibNull/Arm/ArmPlatformHelper.S b/ArmPlatformPkg/Library/ArmPlatformLibNull/Arm/ArmPlatformHelper.S
index aedae55623..342d6d5e0a 100644
--- a/ArmPlatformPkg/Library/ArmPlatformLibNull/Arm/ArmPlatformHelper.S
+++ b/ArmPlatformPkg/Library/ArmPlatformLibNull/Arm/ArmPlatformHelper.S
@@ -10,34 +10,3 @@
 
 ASM_FUNC(ArmPlatformPeiBootAction)
   bx    lr
-
-//UINTN
-//ArmPlatformGetCorePosition (
-//  IN UINTN MpId
-//  );
-ASM_FUNC(ArmPlatformGetCorePosition)
-  and   r1, r0, #ARM_CORE_MASK
-  and   r0, r0, #ARM_CLUSTER_MASK
-  add   r0, r1, r0, LSR #7
-  bx    lr
-
-//UINTN
-//ArmPlatformGetPrimaryCoreMpId (
-//  VOID
-//  );
-ASM_FUNC(ArmPlatformGetPrimaryCoreMpId)
-  MOV32  (r0, FixedPcdGet32 (PcdArmPrimaryCore))
-  bx    lr
-
-//UINTN
-//ArmPlatformIsPrimaryCore (
-//  IN UINTN MpId
-//  );
-ASM_FUNC(ArmPlatformIsPrimaryCore)
-  MOV32  (r1, FixedPcdGet32 (PcdArmPrimaryCoreMask))
-  and   r0, r0, r1
-  MOV32  (r1, FixedPcdGet32 (PcdArmPrimaryCore))
-  cmp   r0, r1
-  moveq r0, #1
-  movne r0, #0
-  bx    lr
diff --git a/ArmPlatformPkg/Library/ArmPlatformLibNull/ArmPlatformLibNull.c b/ArmPlatformPkg/Library/ArmPlatformLibNull/ArmPlatformLibNull.c
index 852275f44f..83c7d16be4 100644
--- a/ArmPlatformPkg/Library/ArmPlatformLibNull/ArmPlatformLibNull.c
+++ b/ArmPlatformPkg/Library/ArmPlatformLibNull/ArmPlatformLibNull.c
@@ -90,10 +90,6 @@ ArmPlatformInitialize (
   IN  UINTN  MpId
   )
 {
-  if (!ArmPlatformIsPrimaryCore (MpId)) {
-    return RETURN_SUCCESS;
-  }
-
   // TODO: Implement me
 
   return RETURN_SUCCESS;