[Qemu-devel] [PATCH] spapr/vio: deprecate the "irq" property

["Cédric Le Goater" <clg@kaod.org>]

VIO devices have an "irq" property that can be used by the sPAPR IRQ
allocator as an IRQ number hint. But it is not set in QEMU nor in
libvirt. It brings unnecessary complexity to the underlying layers
managing the IRQ number space and it is in full opposition with the
new static IRQ allocator we want to introduce in sPAPR.

Let's deprecate it to simplify the spapr_irq_alloc routine in the
future.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
---
 qemu-doc.texi      | 12 ++++++++++--
 hw/ppc/spapr_vio.c | 19 ++++++++++++++++++-
 2 files changed, 28 insertions(+), 3 deletions(-)

diff --git a/qemu-doc.texi b/qemu-doc.texi
index f00706b9996c..fd25ddf7a06a 100644
--- a/qemu-doc.texi
+++ b/qemu-doc.texi
@@ -2970,13 +2970,21 @@ support page sizes < 4096 any longer.
 The ``xlnx-ep108'' machine has been replaced by the ``xlnx-zcu102'' machine.
 The ``xlnx-zcu102'' machine has the same features and capabilites in QEMU.
 
-@section Block device options
+@section Device options
 
-@subsection "backing": "" (since 2.12.0)
+@subsection Block device options
+
+@subsubsection "backing": "" (since 2.12.0)
 
 In order to prevent QEMU from automatically opening an image's backing
 chain, use ``"backing": null'' instead.
 
+@subsection vio-spapr-device device options
+
+@subsubsection "irq": "" (since 3.0.0)
+
+The ``irq'' property is obsoleted.
+
 @node Supported build platforms
 @appendix Supported build platforms
 
diff --git a/hw/ppc/spapr_vio.c b/hw/ppc/spapr_vio.c
index 472dd6f33a96..28bb3b849b9b 100644
--- a/hw/ppc/spapr_vio.c
+++ b/hw/ppc/spapr_vio.c
@@ -22,6 +22,7 @@
 #include "qemu/osdep.h"
 #include "qemu/error-report.h"
 #include "qapi/error.h"
+#include "qapi/visitor.h"
 #include "hw/hw.h"
 #include "qemu/log.h"
 #include "sysemu/sysemu.h"
@@ -41,8 +42,24 @@
 
 #include <libfdt.h>
 
+static void spapr_vio_getset_irq(Object *obj, Visitor *v, const char *name,
+                              void *opaque, Error **errp)
+{
+    Property *prop = opaque;
+    uint32_t *ptr = qdev_get_prop_ptr(DEVICE(obj), prop);
+
+    warn_report(TYPE_VIO_SPAPR_DEVICE " '%s' property is deprecated", name);
+    visit_type_uint32(v, name, ptr, errp);
+}
+
+static const PropertyInfo spapr_vio_irq_propinfo = {
+    .name = "irq",
+    .get = spapr_vio_getset_irq,
+    .set = spapr_vio_getset_irq,
+};
+
 static Property spapr_vio_props[] = {
-    DEFINE_PROP_UINT32("irq", VIOsPAPRDevice, irq, 0), \
+    DEFINE_PROP("irq", VIOsPAPRDevice, irq, spapr_vio_irq_propinfo, uint32_t),
     DEFINE_PROP_END_OF_LIST(),
 };
 
-- 
2.13.6