From 9d0f3dd35d86fba542d38467ff679fd961e0f6f0 Mon Sep 17 00:00:00 2001
From: Kun Qin <kuqin@microsoft.com>
Date: Thu, 10 Oct 2024 15:40:12 -0700
Subject: [PATCH] ArmPkg: ArmArchTimerLib: Update operations to be 64 bit wide

The existing operation in ArmArchTimerLib is operating on UINT32 or
UINT64 based on the target system. This casting game originates from the
fact that timer frequency is UINTN type.

This change will simply promote all operations to UINT64 based, which
will remove the casting and conditional #if in the code for better
portability and readability.

Cc: Leif Lindholm <quic_llindhol@quicinc.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Sami Mujawar <sami.mujawar@arm.com>

Signed-off-by: Kun Qin <kun.qin@microsoft.com>
---
 .../Library/ArmArchTimerLib/ArmArchTimerLib.c | 26 +++++++------------
 1 file changed, 10 insertions(+), 16 deletions(-)

diff --git a/ArmPkg/Library/ArmArchTimerLib/ArmArchTimerLib.c b/ArmPkg/Library/ArmArchTimerLib/ArmArchTimerLib.c
index cc1be0125b..8fb183a35d 100644
--- a/ArmPkg/Library/ArmArchTimerLib/ArmArchTimerLib.c
+++ b/ArmPkg/Library/ArmArchTimerLib/ArmArchTimerLib.c
@@ -17,13 +17,6 @@
 
 #define TICKS_PER_MICRO_SEC  (ArmGenericTimerGetTimerFreq ()/1000000U)
 
-// Select appropriate multiply function for platform architecture.
-#ifdef MDE_CPU_ARM
-#define MULT_U64_X_N  MultU64x32
-#else
-#define MULT_U64_X_N  MultU64x64
-#endif
-
 /**
   A local utility function that returns the PCD value, if specified.
   Otherwise it defaults to ArmGenericTimerGetTimerFreq.
@@ -69,7 +62,7 @@ MicroSecondDelay (
   //  = MicroSeconds x TICKS_PER_MICRO_SEC
   //  = MicroSeconds x Frequency.10^-6
   TimerTicks64 = DivU64x32 (
-                   MULT_U64_X_N (
+                   MultU64x64 (
                      MicroSeconds,
                      GetPlatformTimerFreq ()
                      ),
@@ -205,8 +198,8 @@ GetTimeInNanoSecond (
   )
 {
   UINT64  NanoSeconds;
-  UINT32  Remainder;
-  UINT32  TimerFreq;
+  UINT64  Remainder;
+  UINT64  TimerFreq;
 
   TimerFreq = GetPlatformTimerFreq ();
   //
@@ -214,8 +207,8 @@ GetTimeInNanoSecond (
   // Time = --------- x 1,000,000,000
   //        Frequency
   //
-  NanoSeconds = MULT_U64_X_N (
-                  DivU64x32Remainder (
+  NanoSeconds = MultU64x64 (
+                  DivU64x64Remainder (
                     Ticks,
                     TimerFreq,
                     &Remainder
@@ -227,12 +220,13 @@ GetTimeInNanoSecond (
   // Frequency < 0x100000000, so Remainder < 0x100000000, then (Remainder * 1,000,000,000)
   // will not overflow 64-bit.
   //
-  NanoSeconds += DivU64x32 (
-                   MULT_U64_X_N (
-                     (UINT64)Remainder,
+  NanoSeconds += DivU64x64Remainder (
+                   MultU64x64 (
+                     Remainder,
                      1000000000U
                      ),
-                   TimerFreq
+                   TimerFreq,
+                   NULL
                    );
 
   return NanoSeconds;