[PATCH 0/4] allow to deprecate objects and devices

[PATCH 0/4] allow to deprecate objects and devices

[Gerd Hoffmann]

Put some infrastructure in place to allow tagging objects (including
devices) as deprected.  Use it to mark the ohci pci host adapter and
the usb hub as deprecated.

Gerd Hoffmann (4):
  qom: allow to mark objects (including devices) as deprecated.
  usb: add config options for the hub and hid devices
  usb/ohci-pci: deprecate, don't build by default
  usb/hub: deprecate, don't build by default

 include/qom/object.h  |  1 +
 hw/usb/dev-hub.c      |  1 +
 hw/usb/hcd-ohci-pci.c |  1 +
 qom/qom-qmp-cmds.c    |  4 ++++
 system/qdev-monitor.c |  5 +++++
 hw/usb/Kconfig        | 10 +++++++++-
 hw/usb/meson.build    |  4 ++--
 qapi/qom.json         |  4 +++-
 8 files changed, 26 insertions(+), 4 deletions(-)

-- 
2.45.1

[PATCH 1/4] qom: allow to mark objects (including devices) as deprecated.

[Gerd Hoffmann]

Add deprecation_note field (string) to ObjectClass.
Add deprecated bool to ObjectTypeInfo, report in 'qom-list-types'.
Print the note when listing devices via '-device help'.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 include/qom/object.h  | 1 +
 qom/qom-qmp-cmds.c    | 4 ++++
 system/qdev-monitor.c | 5 +++++
 qapi/qom.json         | 4 +++-
 4 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/include/qom/object.h b/include/qom/object.h
index 13d3a655ddf9..6c682aa0135f 100644
--- a/include/qom/object.h
+++ b/include/qom/object.h
@@ -136,6 +136,7 @@ struct ObjectClass
     ObjectUnparent *unparent;
 
     GHashTable *properties;
+    const char *deprecation_note;
 };
 
 /**
diff --git a/qom/qom-qmp-cmds.c b/qom/qom-qmp-cmds.c
index e91a2353472a..43de9c9ae141 100644
--- a/qom/qom-qmp-cmds.c
+++ b/qom/qom-qmp-cmds.c
@@ -101,6 +101,10 @@ static void qom_list_types_tramp(ObjectClass *klass, void *data)
     if (parent) {
         info->parent = g_strdup(object_class_get_name(parent));
     }
+    if (klass->deprecation_note) {
+        info->has_deprecated = true;
+        info->deprecated = true;
+    }
 
     QAPI_LIST_PREPEND(*pret, info);
 }
diff --git a/system/qdev-monitor.c b/system/qdev-monitor.c
index 6af6ef7d667f..704be312e1a7 100644
--- a/system/qdev-monitor.c
+++ b/system/qdev-monitor.c
@@ -144,6 +144,8 @@ static bool qdev_class_has_alias(DeviceClass *dc)
 
 static void qdev_print_devinfo(DeviceClass *dc)
 {
+    ObjectClass *klass = OBJECT_CLASS(dc);
+
     qemu_printf("name \"%s\"", object_class_get_name(OBJECT_CLASS(dc)));
     if (dc->bus_type) {
         qemu_printf(", bus %s", dc->bus_type);
@@ -157,6 +159,9 @@ static void qdev_print_devinfo(DeviceClass *dc)
     if (!dc->user_creatable) {
         qemu_printf(", no-user");
     }
+    if (klass->deprecation_note) {
+        qemu_printf(", deprecated \"%s\"", klass->deprecation_note);
+    }
     qemu_printf("\n");
 }
 
diff --git a/qapi/qom.json b/qapi/qom.json
index 38dde6d785ac..bd062feabaf7 100644
--- a/qapi/qom.json
+++ b/qapi/qom.json
@@ -163,10 +163,12 @@
 #
 # @parent: Name of parent type, if any (since 2.10)
 #
+# @deprecated: the type is deprecated (since 9.1)
+#
 # Since: 1.1
 ##
 { 'struct': 'ObjectTypeInfo',
-  'data': { 'name': 'str', '*abstract': 'bool', '*parent': 'str' } }
+  'data': { 'name': 'str', '*abstract': 'bool', '*parent': 'str', '*deprecated': 'bool' } }
 
 ##
 # @qom-list-types:
-- 
2.45.1

Re: [PATCH 1/4] qom: allow to mark objects (including devices) as deprecated.

[Daniel P. Berrangé]

On Tue, May 28, 2024 at 11:54:56AM +0200, Gerd Hoffmann wrote:
> Add deprecation_note field (string) to ObjectClass.
> Add deprecated bool to ObjectTypeInfo, report in 'qom-list-types'.
> Print the note when listing devices via '-device help'.
> 
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
> ---
>  include/qom/object.h  | 1 +
>  qom/qom-qmp-cmds.c    | 4 ++++
>  system/qdev-monitor.c | 5 +++++
>  qapi/qom.json         | 4 +++-
>  4 files changed, 13 insertions(+), 1 deletion(-)

I think that object.c, object_init_with_type() should be printing
a message on stderr when creating an instance of a deprecated
object/device, since we do that with machine types and CPUs that
are deprecated.


With regards,
Daniel
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[PATCH 2/4] usb: add config options for the hub and hid devices

[Gerd Hoffmann]

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 hw/usb/Kconfig     | 10 ++++++++++
 hw/usb/meson.build |  4 ++--
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/hw/usb/Kconfig b/hw/usb/Kconfig
index f569ed7eeaa1..84bc7fbe36cd 100644
--- a/hw/usb/Kconfig
+++ b/hw/usb/Kconfig
@@ -65,6 +65,16 @@ config TUSB6010
     bool
     select USB_MUSB
 
+config USB_HUB
+    bool
+    default y
+    depends on USB
+
+config USB_HID
+    bool
+    default y
+    depends on USB
+
 config USB_TABLET_WACOM
     bool
     default y
diff --git a/hw/usb/meson.build b/hw/usb/meson.build
index 23f7f7acb50b..d7de1003e3db 100644
--- a/hw/usb/meson.build
+++ b/hw/usb/meson.build
@@ -35,8 +35,8 @@ system_ss.add(when: 'CONFIG_XLNX_VERSAL', if_true: files('xlnx-versal-usb2-ctrl-
 system_ss.add(when: 'CONFIG_XLNX_USB_SUBSYS', if_true: files('xlnx-usb-subsystem.c'))
 
 # emulated usb devices
-system_ss.add(when: 'CONFIG_USB', if_true: files('dev-hub.c'))
-system_ss.add(when: 'CONFIG_USB', if_true: files('dev-hid.c'))
+system_ss.add(when: 'CONFIG_USB_HUB', if_true: files('dev-hub.c'))
+system_ss.add(when: 'CONFIG_USB_HID', if_true: files('dev-hid.c'))
 system_ss.add(when: 'CONFIG_USB_TABLET_WACOM', if_true: files('dev-wacom.c'))
 system_ss.add(when: 'CONFIG_USB_STORAGE_CORE', if_true: files('dev-storage.c'))
 system_ss.add(when: 'CONFIG_USB_STORAGE_BOT', if_true: files('dev-storage-bot.c'))
-- 
2.45.1

Re: [PATCH 2/4] usb: add config options for the hub and hid devices

[Thomas Huth]

On 28/05/2024 11.54, Gerd Hoffmann wrote:
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
> ---
>   hw/usb/Kconfig     | 10 ++++++++++
>   hw/usb/meson.build |  4 ++--
>   2 files changed, 12 insertions(+), 2 deletions(-)

Reviewed-by: Thomas Huth <thuth@redhat.com>

[PATCH 3/4] usb/ohci-pci: deprecate, don't build by default

[Gerd Hoffmann]

The xhci host adapter is the much better choice.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 hw/usb/hcd-ohci-pci.c | 1 +
 hw/usb/Kconfig        | 1 -
 2 files changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/usb/hcd-ohci-pci.c b/hw/usb/hcd-ohci-pci.c
index 33ed9b6f5a52..88de657def71 100644
--- a/hw/usb/hcd-ohci-pci.c
+++ b/hw/usb/hcd-ohci-pci.c
@@ -143,6 +143,7 @@ static void ohci_pci_class_init(ObjectClass *klass, void *data)
     dc->hotpluggable = false;
     dc->vmsd = &vmstate_ohci;
     dc->reset = usb_ohci_reset_pci;
+    klass->deprecation_note = "use qemu-xhci instead";
 }
 
 static const TypeInfo ohci_pci_info = {
diff --git a/hw/usb/Kconfig b/hw/usb/Kconfig
index 84bc7fbe36cd..c4a6ea5a687f 100644
--- a/hw/usb/Kconfig
+++ b/hw/usb/Kconfig
@@ -17,7 +17,6 @@ config USB_OHCI_SYSBUS
 
 config USB_OHCI_PCI
     bool
-    default y if PCI_DEVICES
     depends on PCI
     select USB_OHCI
 
-- 
2.45.1

Re: [PATCH 3/4] usb/ohci-pci: deprecate, don't build by default

[Thomas Huth]

On 28/05/2024 11.54, Gerd Hoffmann wrote:
> The xhci host adapter is the much better choice.
> 
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
> ---
>   hw/usb/hcd-ohci-pci.c | 1 +
>   hw/usb/Kconfig        | 1 -
>   2 files changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/hw/usb/hcd-ohci-pci.c b/hw/usb/hcd-ohci-pci.c
> index 33ed9b6f5a52..88de657def71 100644
> --- a/hw/usb/hcd-ohci-pci.c
> +++ b/hw/usb/hcd-ohci-pci.c
> @@ -143,6 +143,7 @@ static void ohci_pci_class_init(ObjectClass *klass, void *data)
>       dc->hotpluggable = false;
>       dc->vmsd = &vmstate_ohci;
>       dc->reset = usb_ohci_reset_pci;
> +    klass->deprecation_note = "use qemu-xhci instead";
>   }
>   
>   static const TypeInfo ohci_pci_info = {
> diff --git a/hw/usb/Kconfig b/hw/usb/Kconfig
> index 84bc7fbe36cd..c4a6ea5a687f 100644
> --- a/hw/usb/Kconfig
> +++ b/hw/usb/Kconfig
> @@ -17,7 +17,6 @@ config USB_OHCI_SYSBUS
>   
>   config USB_OHCI_PCI
>       bool
> -    default y if PCI_DEVICES
>       depends on PCI
>       select USB_OHCI

Not sure whether we should disable it by default just because it is 
deprecated. We don't do that for any other devices as far as I know.

Anyway, you should add the device to docs/about/deprecated.rst to really 
mark it as deprecated, since that's our official list (AFAIK).

Also, there are still some machines that use this device:

$ grep -r USB_OHCI_PCI *
hw/hppa/Kconfig:    imply USB_OHCI_PCI
hw/mips/Kconfig:    imply USB_OHCI_PCI
hw/ppc/Kconfig:    imply USB_OHCI_PCI
hw/ppc/Kconfig:    imply USB_OHCI_PCI

pseries could certainly continue without OHCI AFAICT, but the others? Maybe 
this needs some discussion first... (thus putting some more people on CC:)

  Thomas

Re: [PATCH 3/4] usb/ohci-pci: deprecate, don't build by default

[Helge Deller]

On 5/28/24 12:35, Thomas Huth wrote:
> On 28/05/2024 11.54, Gerd Hoffmann wrote:
>> The xhci host adapter is the much better choice.
>>
>> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
>> ---
>>   hw/usb/hcd-ohci-pci.c | 1 +
>>   hw/usb/Kconfig        | 1 -
>>   2 files changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/hw/usb/hcd-ohci-pci.c b/hw/usb/hcd-ohci-pci.c
>> index 33ed9b6f5a52..88de657def71 100644
>> --- a/hw/usb/hcd-ohci-pci.c
>> +++ b/hw/usb/hcd-ohci-pci.c
>> @@ -143,6 +143,7 @@ static void ohci_pci_class_init(ObjectClass *klass, void *data)
>>       dc->hotpluggable = false;
>>       dc->vmsd = &vmstate_ohci;
>>       dc->reset = usb_ohci_reset_pci;
>> +    klass->deprecation_note = "use qemu-xhci instead";
>>   }
>>   static const TypeInfo ohci_pci_info = {
>> diff --git a/hw/usb/Kconfig b/hw/usb/Kconfig
>> index 84bc7fbe36cd..c4a6ea5a687f 100644
>> --- a/hw/usb/Kconfig
>> +++ b/hw/usb/Kconfig
>> @@ -17,7 +17,6 @@ config USB_OHCI_SYSBUS
>>   config USB_OHCI_PCI
>>       bool
>> -    default y if PCI_DEVICES
>>       depends on PCI
>>       select USB_OHCI
>
> Not sure whether we should disable it by default just because it is deprecated. We don't do that for any other devices as far as I know.
>
> Anyway, you should add the device to docs/about/deprecated.rst to really mark it as deprecated, since that's our official list (AFAIK).
>
> Also, there are still some machines that use this device:
>
> $ grep -r USB_OHCI_PCI *
> hw/hppa/Kconfig:    imply USB_OHCI_PCI
> hw/mips/Kconfig:    imply USB_OHCI_PCI
> hw/ppc/Kconfig:    imply USB_OHCI_PCI
> hw/ppc/Kconfig:    imply USB_OHCI_PCI
>
> pseries could certainly continue without OHCI AFAICT, but the others? Maybe this needs some discussion first... (thus putting some more people on CC:)

There was never a XHCI host on any of the hppa machines, but
the latest generation of HP machines do have built-in OHCI controllers.
So, deprecating OHCI in favor of XHCI will prevent emulation of HP-UX
on the hppa target.
So, for hppa the "xhci host adapter is NOT the much better choice.".

Helge

Re: [PATCH 3/4] usb/ohci-pci: deprecate, don't build by default

[Paolo Bonzini]

On Tue, May 28, 2024 at 12:35 PM Thomas Huth <thuth@redhat.com> wrote:
> > diff --git a/hw/usb/Kconfig b/hw/usb/Kconfig
> > index 84bc7fbe36cd..c4a6ea5a687f 100644
> > --- a/hw/usb/Kconfig
> > +++ b/hw/usb/Kconfig
> > @@ -17,7 +17,6 @@ config USB_OHCI_SYSBUS
> >
> >   config USB_OHCI_PCI
> >       bool
> > -    default y if PCI_DEVICES
> >       depends on PCI
> >       select USB_OHCI
>
> Not sure whether we should disable it by default just because it is
> deprecated. We don't do that for any other devices as far as I know.
> Anyway, you should add the device to docs/about/deprecated.rst to really
> mark it as deprecated, since that's our official list (AFAIK).

That would mean removing it, but that's a bad idea. It's not like the
device is blocking improvements elsewhere (in fact it's not even
removing any code because the sysbus OHCI is still there).

> Also, there are still some machines that use this device:
>
> $ grep -r USB_OHCI_PCI *
> hw/hppa/Kconfig:    imply USB_OHCI_PCI
> hw/mips/Kconfig:    imply USB_OHCI_PCI
> hw/ppc/Kconfig:    imply USB_OHCI_PCI
> hw/ppc/Kconfig:    imply USB_OHCI_PCI
>
> pseries could certainly continue without OHCI AFAICT, but the others?

Yeah, this needs to be a per-machine type choice to warn about
discouraged devices. Some, such as Cirrus, can probably be
unconditional, but still I wouldn't remove them.


Paolo

Re: [PATCH 3/4] usb/ohci-pci: deprecate, don't build by default

[Mark Cave-Ayland]

On 28/05/2024 11:35, Thomas Huth wrote:

> On 28/05/2024 11.54, Gerd Hoffmann wrote:
>> The xhci host adapter is the much better choice.
>>
>> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
>> ---
>>   hw/usb/hcd-ohci-pci.c | 1 +
>>   hw/usb/Kconfig        | 1 -
>>   2 files changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/hw/usb/hcd-ohci-pci.c b/hw/usb/hcd-ohci-pci.c
>> index 33ed9b6f5a52..88de657def71 100644
>> --- a/hw/usb/hcd-ohci-pci.c
>> +++ b/hw/usb/hcd-ohci-pci.c
>> @@ -143,6 +143,7 @@ static void ohci_pci_class_init(ObjectClass *klass, void *data)
>>       dc->hotpluggable = false;
>>       dc->vmsd = &vmstate_ohci;
>>       dc->reset = usb_ohci_reset_pci;
>> +    klass->deprecation_note = "use qemu-xhci instead";
>>   }
>>   static const TypeInfo ohci_pci_info = {
>> diff --git a/hw/usb/Kconfig b/hw/usb/Kconfig
>> index 84bc7fbe36cd..c4a6ea5a687f 100644
>> --- a/hw/usb/Kconfig
>> +++ b/hw/usb/Kconfig
>> @@ -17,7 +17,6 @@ config USB_OHCI_SYSBUS
>>   config USB_OHCI_PCI
>>       bool
>> -    default y if PCI_DEVICES
>>       depends on PCI
>>       select USB_OHCI
> 
> Not sure whether we should disable it by default just because it is deprecated. We 
> don't do that for any other devices as far as I know.
> 
> Anyway, you should add the device to docs/about/deprecated.rst to really mark it as 
> deprecated, since that's our official list (AFAIK).
> 
> Also, there are still some machines that use this device:
> 
> $ grep -r USB_OHCI_PCI *
> hw/hppa/Kconfig:    imply USB_OHCI_PCI
> hw/mips/Kconfig:    imply USB_OHCI_PCI
> hw/ppc/Kconfig:    imply USB_OHCI_PCI
> hw/ppc/Kconfig:    imply USB_OHCI_PCI
> 
> pseries could certainly continue without OHCI AFAICT, but the others? Maybe this 
> needs some discussion first... (thus putting some more people on CC:)
> 
>   Thomas

The mac99 machine has an in-built OHCI PCI interface so I don't think this device 
should be marked as deprecated. Normally in these cases isn't it just a matter of 
updating documentation to recommend XHCI over OHCI for particular uses?


ATB,

Mark.

[PATCH 4/4] usb/hub: deprecate, don't build by default

[Gerd Hoffmann]

The hub supports only USB 1.1.  When running out of usb ports it is in
almost all cases the much better choice to add another usb host adapter
(or increase the number of root ports when using xhci) instead of using
the usb hub.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 hw/usb/dev-hub.c | 1 +
 hw/usb/Kconfig   | 1 -
 2 files changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/usb/dev-hub.c b/hw/usb/dev-hub.c
index 06e9537d0356..68444d39534f 100644
--- a/hw/usb/dev-hub.c
+++ b/hw/usb/dev-hub.c
@@ -686,6 +686,7 @@ static void usb_hub_class_initfn(ObjectClass *klass, void *data)
     set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
     dc->fw_name = "hub";
     dc->vmsd = &vmstate_usb_hub;
+    klass->deprecation_note = "use more root ports or additional hostadapters instead";
     device_class_set_props(dc, usb_hub_properties);
 }
 
diff --git a/hw/usb/Kconfig b/hw/usb/Kconfig
index c4a6ea5a687f..a8644c43296b 100644
--- a/hw/usb/Kconfig
+++ b/hw/usb/Kconfig
@@ -66,7 +66,6 @@ config TUSB6010
 
 config USB_HUB
     bool
-    default y
     depends on USB
 
 config USB_HID
-- 
2.45.1