target/arm: Move define_debug_regs() to debug_helper.c

The target/arm/helper.c file is very long and is a grabbag of all
kinds of functionality.  We have already a debug_helper.c which has
code for implementing architectural debug.  Move the code which
defines the debug-related system registers out to this file also.
This affects the define_debug_regs() function and the various
functions and arrays which are used only by it.

The functions raw_write() and arm_mdcr_el2_eff() and
define_debug_regs() now need to be global rather than local to
helper.c; everything else is pure code movement.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220630194116.3438513-3-peter.maydell@linaro.org

target/arm/cpregs.h

@@ -442,6 +442,9 @@ void arm_cp_write_ignore(CPUARMState *env, const ARMCPRegInfo *ri,
 /* CPReadFn that can be used for read-as-zero behaviour */
 uint64_t arm_cp_read_zero(CPUARMState *env, const ARMCPRegInfo *ri);
 
+/* CPWriteFn that just writes the value to ri->fieldoffset */
+void raw_write(CPUARMState *env, const ARMCPRegInfo *ri, uint64_t value);
+
 /*
  * CPResetFn that does nothing, for use if no reset is required even
  * if fieldoffset is non zero.

target/arm/internals.h

@@ -1307,6 +1307,15 @@ int exception_target_el(CPUARMState *env);
 bool arm_singlestep_active(CPUARMState *env);
 bool arm_generate_debug_exceptions(CPUARMState *env);
 
+/* Add the cpreg definitions for debug related system registers */
+void define_debug_regs(ARMCPU *cpu);
+
+/* Effective value of MDCR_EL2 */
+static inline uint64_t arm_mdcr_el2_eff(CPUARMState *env)
+{
+    return arm_is_el2_enabled(env) ? env->cp15.mdcr_el2 : 0;
+}
+
 /* Powers of 2 for sve_vq_map et al. */
 #define SVE_VQ_POW2_MAP                                 \
     ((1 << (1 - 1)) | (1 << (2 - 1)) |                  \