Allow targets to register their legacy target_get_monitor_def()
in SysemuCPUOps; check it first in get_monitor_def() otherwise
fall back to previous per-target helper.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
---
 include/hw/core/sysemu-cpu-ops.h |  8 ++++++++
 monitor/hmp-target.c             | 11 ++++++++---
 2 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/include/hw/core/sysemu-cpu-ops.h b/include/hw/core/sysemu-cpu-ops.h
index 7b2d2d2610f..5b831393cf4 100644
--- a/include/hw/core/sysemu-cpu-ops.h
+++ b/include/hw/core/sysemu-cpu-ops.h
@@ -85,6 +85,14 @@ typedef struct SysemuCPUOps {
      */
     bool (*internal_is_big_endian)(CPUState *cpu);
 
+    /**
+     * @monitor_get_register: Callback to fill @pval with register @name value.
+     *                        This field is legacy, use @gdb_core_xml_file
+     *                        to dump registers instead.
+     * Returns: 0 on success or negative errno on failure.
+     */
+    int (*monitor_get_register)(CPUState *cs, const char *name, int64_t *pval);
+
     /**
      * @legacy_vmsd: Legacy state for migration.
      *               Do not use in new targets, use #DeviceClass::vmsd instead.
diff --git a/monitor/hmp-target.c b/monitor/hmp-target.c
index a222fd4c96a..46ccbd14aec 100644
--- a/monitor/hmp-target.c
+++ b/monitor/hmp-target.c
@@ -35,6 +35,7 @@
 #include "qapi/qapi-commands-control.h"
 #include "qapi/qapi-commands-misc.h"
 #include "qapi/qapi-commands-machine.h"
+#include "hw/core/sysemu-cpu-ops.h"
 
 /* Make devices configuration available for use in hmp-commands*.hx templates */
 #include CONFIG_DEVICES
@@ -85,9 +86,13 @@ int get_monitor_def(Monitor *mon, int64_t *pval, const char *name)
         }
     }
 
-    ret = target_get_monitor_def(cs, name, &tmp);
-    if (!ret) {
-        *pval = (target_long) tmp;
+    if (cs->cc->sysemu_ops->monitor_get_register) {
+        ret = cs->cc->sysemu_ops->monitor_get_register(cs, name, pval);
+    } else {
+        ret = target_get_monitor_def(cs, name, &tmp);
+        if (!ret) {
+            *pval = (target_long) tmp;
+        }
     }
 
     return ret;
-- 
2.53.0