ArmPkg: Add helper to read the Memory Model Features Register 2

Add helper function to read the MMFR2 register. We will need this to
determine CCIDX support.

Signed-off-by: Rebecca Cran <rebecca@nuviainc.com>
Reviewed-by: Leif Lindholm <leif@nuviainc.com>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>

diff --git a/ArmPkg/Library/ArmLib/AArch64/AArch64Lib.h b/ArmPkg/Library/ArmLib/AArch64/AArch64Lib.h
index 85bcecda730f3a9740e21ef8f6995a2764eb9351..cfc0c878a4152145c9b3f73c1e14dab4db93b28e 100644 (file)
--- a/ArmPkg/Library/ArmLib/AArch64/AArch64Lib.h
+++ b/ArmPkg/Library/ArmLib/AArch64/AArch64Lib.h
@@ -41,5 +41,16 @@ EFIAPI
 ArmReadIdAA64Pfr0 (\r
   VOID\r
   );\r
+\r
+/** Reads the ID_AA64MMFR2_EL1 register.\r
+\r
+   @return The contents of the ID_AA64MMFR2_EL1 register.\r
+**/\r
+UINTN\r
+EFIAPI\r
+ArmReadIdAA64Mmfr2 (\r
+  VOID\r
+  );\r
+\r
 #endif // __AARCH64_LIB_H__\r
 \r

diff --git a/ArmPkg/Library/ArmLib/AArch64/AArch64Support.S b/ArmPkg/Library/ArmLib/AArch64/AArch64Support.S
index 129205d2ac27e323b37852e850771bf49adca063..d3cc1e86716b93a44265c1b133dee945ad335ae6 100644 (file)
--- a/ArmPkg/Library/ArmLib/AArch64/AArch64Support.S
+++ b/ArmPkg/Library/ArmLib/AArch64/AArch64Support.S
@@ -425,6 +425,9 @@ ASM_FUNC(ArmCallWFI)
   wfi\r
   ret\r
 \r
+ASM_FUNC(ArmReadIdAA64Mmfr2)\r
+  mrs   x0, ID_AA64MMFR2_EL1           // read EL1 MMFR2\r
+  ret\r
 \r
 ASM_FUNC(ArmReadMpidr)\r
   mrs   x0, mpidr_el1           // read EL1 MPIDR\r