ArmPkg: fix ArmWriteCntkCtl simple code bug

We need to use msr instruction to write system register. It seems the
code was simply copied from ArmReadCntkCtl.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Heyi Guo <heyi.guo@linaro.org>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@17440 6f19259b-4bc3-4df7-8a09-765794883524

diff --git a/ArmPkg/Library/ArmLib/AArch64/AArch64ArchTimerSupport.S b/ArmPkg/Library/ArmLib/AArch64/AArch64ArchTimerSupport.S
index 1ac01086aa3a797acac8257cec351451112f40fb..3944d8bcb4f11ea284b2582ce05f1eef3549a91b 100644 (file)
--- a/ArmPkg/Library/ArmLib/AArch64/AArch64ArchTimerSupport.S
+++ b/ArmPkg/Library/ArmLib/AArch64/AArch64ArchTimerSupport.S
@@ -58,7 +58,7 @@ ASM_PFX(ArmReadCntkCtl):
 \r
 \r
 ASM_PFX(ArmWriteCntkCtl):\r
-  mrs   x0, cntkctl_el1          // Write to CNTK_CTL (Timer PL1 Control Register)\r
+  msr   cntkctl_el1, x0          // Write to CNTK_CTL (Timer PL1 Control Register)\r
   ret\r
 \r
 \r