Use PFR0 to identify need for mitigation of CVE-2017-5915
If the CSV2 field reads as 1 then branch targets trained in one
context cannot affect speculative execution in a different context.
In that case skip the workaround on Cortex A75.
Change-Id: I4d5504cba516a67311fb5f0657b08f72909cbd38
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>
diff --git a/include/lib/aarch64/arch.h b/include/lib/aarch64/arch.h
index 13a8c79..7f3e9fa 100644
--- a/include/lib/aarch64/arch.h
+++ b/include/lib/aarch64/arch.h
@@ -117,6 +117,9 @@
#define ID_AA64PFR0_SVE_SHIFT U(32)
#define ID_AA64PFR0_SVE_MASK U(0xf)
#define ID_AA64PFR0_SVE_LENGTH U(4)
+#define ID_AA64PFR0_CSV2_SHIFT U(56)
+#define ID_AA64PFR0_CSV2_MASK U(0xf)
+#define ID_AA64PFR0_CSV2_LENGTH U(4)
/* ID_AA64DFR0_EL1.PMS definitions (for ARMv8.2+) */
#define ID_AA64DFR0_PMS_SHIFT U(32)