[PATCH 1/2] bsps/aarch64: Ensure FPU trap state is consistent

[Kinsey Moore]

RTEMS may be booted from a dirty environment. Ensure that FPU trap
settings are consistent.
---
 bsps/aarch64/shared/start/start.S | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/bsps/aarch64/shared/start/start.S b/bsps/aarch64/shared/start/start.S
index 8bd4f86f4e..de0fdf4c80 100644
--- a/bsps/aarch64/shared/start/start.S
+++ b/bsps/aarch64/shared/start/start.S
@@ -307,6 +307,16 @@ _el1_start:
 
   /* FPU does not need to be enabled on AArch64 */
 
+  /* Ensure FPU traps are disabled by default */
+  mrs x0, FPCR
+  bic x0, x0, #(1 << 8)
+  bic x0, x0, #(1 << 9)
+  bic x0, x0, #(1 << 10)
+  bic x0, x0, #(1 << 11)
+  bic x0, x0, #(1 << 12)
+  bic x0, x0, #(1 << 15)
+  msr FPCR, x0
+
 #endif /* AARCH64_MULTILIB_VFP */
 
   /* Branch to start hook 1 */
-- 
2.30.2