arch-arm: CPTR.FPEN controlling SVE enablement

CheckSveEnabled shouldn't check for .ZEN only.
SVE instructions require Advanced SIMD to be supported as
well (CPTR.FPEN) with the caveat of ZEN check having priority
over the FPEN.

Change-Id: Ia1b5f7df3e25e7ffcad472542cb973635f62637b
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Ciro Santilli <ciro.santilli@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/28768
Tested-by: kokoro <noreply+kokoro@google.com>

diff --git a/src/arch/arm/insts/static_inst.cc b/src/arch/arm/insts/static_inst.cc
index 6da8b770e1aa2f5718791071e8a69b5cc2ee4ff7..9ece0e6d29f919dcdd76909d02df95d926cb3f57 100644 (file)
--- a/src/arch/arm/insts/static_inst.cc
+++ b/src/arch/arm/insts/static_inst.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2010-2014, 2016-2019 ARM Limited
+ * Copyright (c) 2010-2014, 2016-2020 ARM Limited
  * Copyright (c) 2013 Advanced Micro Devices, Inc.
  * All rights reserved
  *
@@ -987,20 +987,33 @@ Fault
 ArmStaticInst::checkSveEnabled(ThreadContext *tc, CPSR cpsr, CPACR cpacr) const
 {
     const ExceptionLevel el = (ExceptionLevel) (uint8_t) cpsr.el;
-    if ((el == EL0 && cpacr.zen != 0x3) ||
-        (el == EL1 && !(cpacr.zen & 0x1)))
-        return sveAccessTrap(EL1);
+    // Check if access disabled in CPACR_EL1
+    if (el <= EL1 && !ELIsInHost(tc, el)) {
+        if ((el == EL0 && cpacr.zen == 0x1) ||
+            (!(cpacr.zen & 0x1)))
+            return sveAccessTrap(EL1);
+
+        if ((el == EL0 && cpacr.fpen == 0x1) ||
+            (!(cpacr.fpen & 0x1)))
+            return advSIMDFPAccessTrap64(EL1);
+    }
 
+    // Check if access disabled in CPTR_EL2
     if (ArmSystem::haveVirtualization(tc) && el <= EL2) {
         CPTR cptr_en_check = tc->readMiscReg(MISCREG_CPTR_EL2);
         if (cptr_en_check.tz)
             return sveAccessTrap(EL2);
+        if (cptr_en_check.tfp)
+            return advSIMDFPAccessTrap64(EL2);
     }
 
+    // Check if access disabled in CPTR_EL3
     if (ArmSystem::haveSecurity(tc)) {
         CPTR cptr_en_check = tc->readMiscReg(MISCREG_CPTR_EL3);
         if (!cptr_en_check.ez)
             return sveAccessTrap(EL3);
+        if (cptr_en_check.tfp)
+            return advSIMDFPAccessTrap64(EL3);
     }
 
     return NoFault;