[PATCH v2 3/8] ArmPkg: add functions to read SVE/SME info

["Marcin Juszkiewicz" <marcin.juszkiewicz@linaro.org>]

ID_AA64ZFR0_EL1 and ID_AA64SMFR0_EL1 system registers are needed for
ArmCpuInfo application to show state of SVE/SME support.

Signed-off-by: Marcin Juszkiewicz <marcin.juszkiewicz@linaro.org>
---
 ArmPkg/Library/ArmLib/ArmBaseLib.inf           |  5 +++++
 ArmPkg/Library/ArmLib/AArch64/AArch64Lib.h     | 12 ++++++++++++
 ArmPkg/Library/ArmLib/AArch64/AArch64Support.S | 10 ++++++++++
 3 files changed, 27 insertions(+)

diff --git a/ArmPkg/Library/ArmLib/ArmBaseLib.inf b/ArmPkg/Library/ArmLib/ArmBaseLib.inf
index e37d85bee471..8b5eda337fe3 100644
--- a/ArmPkg/Library/ArmLib/ArmBaseLib.inf
+++ b/ArmPkg/Library/ArmLib/ArmBaseLib.inf
@@ -48,3 +48,8 @@ [Packages]
 
 [FeaturePcd.ARM]
   gArmTokenSpaceGuid.PcdNormalMemoryNonshareableOverride
+
+# to access ID_AA64ZFR0_EL1 and ID_AA64SMFR0_EL1 system registers
+# we need to enable SME
+[BuildOptions]
+  GCC:*_*_AARCH64_ASM_FLAGS = -march=armv8-a+sme
diff --git a/ArmPkg/Library/ArmLib/AArch64/AArch64Lib.h b/ArmPkg/Library/ArmLib/AArch64/AArch64Lib.h
index 6380a019ddc5..2fd256f4acc8 100644
--- a/ArmPkg/Library/ArmLib/AArch64/AArch64Lib.h
+++ b/ArmPkg/Library/ArmLib/AArch64/AArch64Lib.h
@@ -102,4 +102,16 @@ ArmReadIdAA64Pfr1 (
   VOID
   );
 
+UINTN
+EFIAPI
+ArmReadIdAA64Smfr0 (
+  VOID
+  );
+
+UINTN
+EFIAPI
+ArmReadIdAA64Zfr0 (
+  VOID
+  );
+
 #endif // AARCH64_LIB_H_
diff --git a/ArmPkg/Library/ArmLib/AArch64/AArch64Support.S b/ArmPkg/Library/ArmLib/AArch64/AArch64Support.S
index a7111e51882c..c996fa8dbbc3 100644
--- a/ArmPkg/Library/ArmLib/AArch64/AArch64Support.S
+++ b/ArmPkg/Library/ArmLib/AArch64/AArch64Support.S
@@ -524,4 +524,14 @@ ASM_FUNC(ArmReadIdAA64Pfr1)
   mrs   x0, ID_AA64PFR1_EL1
   ret
 
+
+ASM_FUNC(ArmReadIdAA64Smfr0)
+  mrs   x0, ID_AA64SMFR0_EL1
+  ret
+
+
+ASM_FUNC(ArmReadIdAA64Zfr0)
+  mrs   x0, ID_AA64ZFR0_EL1
+  ret
+
 ASM_FUNCTION_REMOVE_IF_UNREFERENCED
-- 
2.40.1