[PATCH 1/2] hw/misc/mos6522: Expose x-query-mos6522-devices QMP command

[Philippe Mathieu-Daudé]

This is a counterpart to the HMP "info via" command. It is being
added with an "x-" prefix because this QMP command is intended as an
adhoc debugging tool and will thus not be modelled in QAPI as fully
structured data, nor will it have long term guaranteed stability.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 MAINTAINERS             |  2 +-
 qapi/machine.json       | 17 +++++++++++++++++
 hw/misc/mos6522-stubs.c | 18 ++++++++++++++++++
 hw/misc/mos6522.c       |  5 +++--
 hw/misc/meson.build     |  3 ++-
 5 files changed, 41 insertions(+), 4 deletions(-)
 create mode 100644 hw/misc/mos6522-stubs.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 951556224a..e86638c68c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1453,7 +1453,7 @@ F: hw/ppc/mac_newworld.c
 F: hw/pci-host/uninorth.c
 F: hw/pci-bridge/dec.[hc]
 F: hw/misc/macio/
-F: hw/misc/mos6522.c
+F: hw/misc/mos6522*.c
 F: hw/nvram/mac_nvram.c
 F: hw/ppc/fw_cfg.c
 F: hw/input/adb*
diff --git a/qapi/machine.json b/qapi/machine.json
index 1283d14493..a82b8dd39d 100644
--- a/qapi/machine.json
+++ b/qapi/machine.json
@@ -1865,6 +1865,23 @@
   'data': { 'filename': 'str' },
   'if': 'CONFIG_FDT' }
 
+##
+# @x-query-mos6522-devices:
+#
+# Query information on MOS6522 VIA devices
+#
+# Features:
+#
+# @unstable: This command is meant for debugging.
+#
+# Returns: MOS6522 VIA devices information
+#
+# Since: 9.1
+##
+{ 'command': 'x-query-mos6522-devices',
+  'returns': 'HumanReadableText',
+  'features': [ 'unstable' ]}
+
 ##
 # @x-query-interrupt-controllers:
 #
diff --git a/hw/misc/mos6522-stubs.c b/hw/misc/mos6522-stubs.c
new file mode 100644
index 0000000000..c953f01a16
--- /dev/null
+++ b/hw/misc/mos6522-stubs.c
@@ -0,0 +1,18 @@
+/*
+ * QEMU MOS6522 VIA stubs
+ *
+ * SPDX-FileContributor: Philippe Mathieu-Daudé <philmd@linaro.org>
+ * SPDX-FileCopyrightText: 2024 Linaro Ltd.
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "qapi/qapi-commands-machine.h"
+
+HumanReadableText *qmp_x_query_mos6522_devices(Error **errp)
+{
+    error_setg(errp, "Support for MOS6522 VIA devices not built-in");
+
+    return NULL;
+}
diff --git a/hw/misc/mos6522.c b/hw/misc/mos6522.c
index 515f62e687..b1bb7f54f0 100644
--- a/hw/misc/mos6522.c
+++ b/hw/misc/mos6522.c
@@ -31,6 +31,7 @@
 #include "migration/vmstate.h"
 #include "monitor/monitor.h"
 #include "monitor/hmp.h"
+#include "qapi/qapi-commands-machine.h"
 #include "qapi/type-helpers.h"
 #include "qemu/timer.h"
 #include "qemu/cutils.h"
@@ -576,7 +577,7 @@ static int qmp_x_query_via_foreach(Object *obj, void 
*opaque)
     return 0;
 }
 
-static HumanReadableText *qmp_x_query_via(Error **errp)
+HumanReadableText *qmp_x_query_mos6522_devices(Error **errp)
 {
     g_autoptr(GString) buf = g_string_new("");
 
@@ -589,7 +590,7 @@ static HumanReadableText *qmp_x_query_via(Error **errp)
 void hmp_info_via(Monitor *mon, const QDict *qdict)
 {
     Error *err = NULL;
-    g_autoptr(HumanReadableText) info = qmp_x_query_via(&err);
+    g_autoptr(HumanReadableText) info = qmp_x_query_mos6522_devices(&err);
 
     if (hmp_handle_error(mon, err)) {
         return;
diff --git a/hw/misc/meson.build b/hw/misc/meson.build
index 86596a3888..9fa0e98794 100644
--- a/hw/misc/meson.build
+++ b/hw/misc/meson.build
@@ -18,7 +18,8 @@ system_ss.add(when: 'CONFIG_ARM11SCU', if_true: 
files('arm11scu.c'))
 system_ss.add(when: 'CONFIG_ARM_V7M', if_true: files('armv7m_ras.c'))
 
 # Mac devices
-system_ss.add(when: 'CONFIG_MOS6522', if_true: files('mos6522.c'))
+system_ss.add(when: 'CONFIG_MOS6522', if_true: files('mos6522.c'),
+                                      if_false: files('mos6522-stubs.c'))
 system_ss.add(when: 'CONFIG_DJMEMC', if_true: files('djmemc.c'))
 system_ss.add(when: 'CONFIG_IOSB', if_true: files('iosb.c'))
 
-- 
2.41.0