arch-arm: Adjust breakpoint EC depending on source state

The software breakpoint exception class needs to be adjusted depending
on the source EL's execution state. This change fixes an incorrect
exception class when taking a breakpoint from aarch64.

Change-Id: I99d87a04be6bf9ce3a69f6b19969fa006cfd63a4
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Ciro Santilli <ciro.santilli@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/10809
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>

src/arch/arm/faults.cc

@@ -1543,6 +1543,12 @@ SoftwareBreakpoint::routeToHyp(ThreadContext *tc) const
         (hcr.tge || mdcr.tde);
 }
 
+ExceptionClass
+SoftwareBreakpoint::ec(ThreadContext *tc) const
+{
+    return from64 ? EC_SOFTWARE_BREAKPOINT_64 : vals.ec;
+}
+
 void
 ArmSev::invoke(ThreadContext *tc, const StaticInstPtr &inst) {
     DPRINTF(Faults, "Invoking ArmSev Fault\n");

src/arch/arm/faults.hh

@@ -573,6 +573,7 @@ class SoftwareBreakpoint : public ArmFaultVals<SoftwareBreakpoint>
     SoftwareBreakpoint(ExtMachInst _mach_inst, uint32_t _iss);
 
     bool routeToHyp(ThreadContext *tc) const override;
+    ExceptionClass ec(ThreadContext *tc) const override;
 };
 
 // A fault that flushes the pipe, excluding the faulting instructions

src/arch/arm/types.hh

@@ -623,6 +623,7 @@ namespace ArmISA
         EC_FP_EXCEPTION_64         = 0x2C,
         EC_SERROR                  = 0x2F,
         EC_SOFTWARE_BREAKPOINT     = 0x38,
+        EC_SOFTWARE_BREAKPOINT_64  = 0x3C,
     };
 
     /**