diff mbox series

[04/14] hw/core: Introduce TYPE_SHARED_IRQ

Message ID 20250108092538.11474-5-shentey@gmail.com (mailing list archive)
State New
Headers show
Series i.MX and SDHCI improvements | expand

Commit Message

Bernhard Beschow Jan. 8, 2025, 9:25 a.m. UTC 
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
---
 include/hw/core/shared-irq.h | 39 ++++++++++++++++
 hw/core/shared-irq.c         | 88 ++++++++++++++++++++++++++++++++++++
 hw/core/Kconfig              |  3 ++
 hw/core/meson.build          |  1 +
 4 files changed, 131 insertions(+)
 create mode 100644 include/hw/core/shared-irq.h
 create mode 100644 hw/core/shared-irq.c

Comments

BALATON Zoltan Jan. 8, 2025, 1:53 p.m. UTC | #1 
On Wed, 8 Jan 2025, Bernhard Beschow wrote:
> Signed-off-by: Bernhard Beschow <shentey@gmail.com>
> ---
> include/hw/core/shared-irq.h | 39 ++++++++++++++++
> hw/core/shared-irq.c         | 88 ++++++++++++++++++++++++++++++++++++
> hw/core/Kconfig              |  3 ++
> hw/core/meson.build          |  1 +
> 4 files changed, 131 insertions(+)
> create mode 100644 include/hw/core/shared-irq.h
> create mode 100644 hw/core/shared-irq.c
>
> diff --git a/include/hw/core/shared-irq.h b/include/hw/core/shared-irq.h
> new file mode 100644
> index 0000000000..803c303dd0
> --- /dev/null
> +++ b/include/hw/core/shared-irq.h
> @@ -0,0 +1,39 @@
> +/*
> + * IRQ sharing device.
> + *
> + * Copyright (c) 2025 Bernhard Beschow <shentey@gmail.com>
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +
> +/*
> + * This is a simple device which has one GPIO output line and multiple GPIO
> + * input lines. The output line is active if at least one of the input lines is.

How is this different from TYPE_OR_IRQ. Also or-irq.h is in 
include/hw/or-irq.h not in include/hw/core/ where split-irq.h is so maybe 
these could all be moved to one place for consistency? Or-irq also has a 
reset method, do you need one in this device?

Regards,
BALATON Zoltan

> + *
> + * QEMU interface:
> + *  + N unnamed GPIO inputs: the input lines
> + *  + one unnamed GPIO output: the output line
> + *  + QOM property "num-lines": sets the number of input lines
> + */
> +#ifndef HW_SHARED_IRQ_H
> +#define HW_SHARED_IRQ_H
> +
> +#include "hw/sysbus.h"
> +#include "qom/object.h"
> +
> +#define TYPE_SHARED_IRQ "shared-irq"
> +
> +#define MAX_SHARED_LINES 16
> +
> +
> +OBJECT_DECLARE_SIMPLE_TYPE(SharedIRQ, SHARED_IRQ)
> +
> +struct SharedIRQ {
> +    DeviceState parent_obj;
> +
> +    qemu_irq out_irq;
> +    uint16_t irq_states;
> +    uint8_t num_lines;
> +};
> +
> +#endif
> diff --git a/hw/core/shared-irq.c b/hw/core/shared-irq.c
> new file mode 100644
> index 0000000000..b2a4ea4a66
> --- /dev/null
> +++ b/hw/core/shared-irq.c
> @@ -0,0 +1,88 @@
> +/*
> + * IRQ sharing device.
> + *
> + * Copyright (c) 2025 Bernhard Beschow <shentey@gmail.com>
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +
> +#include "qemu/osdep.h"
> +#include "hw/core/shared-irq.h"
> +#include "hw/irq.h"
> +#include "hw/qdev-properties.h"
> +#include "qapi/error.h"
> +#include "migration/vmstate.h"
> +
> +static void shared_irq_handler(void *opaque, int n, int level)
> +{
> +    SharedIRQ *s = opaque;
> +    uint16_t mask = BIT(n);
> +
> +    if (level) {
> +        s->irq_states |= mask;
> +    } else {
> +        s->irq_states &= ~mask;
> +    }
> +
> +    qemu_set_irq(s->out_irq, !!s->irq_states);
> +}
> +
> +static void shared_irq_init(Object *obj)
> +{
> +    SharedIRQ *s = SHARED_IRQ(obj);
> +
> +    qdev_init_gpio_out(DEVICE(s), &s->out_irq, 1);
> +}
> +
> +static void shared_irq_realize(DeviceState *dev, Error **errp)
> +{
> +    SharedIRQ *s = SHARED_IRQ(dev);
> +
> +    if (s->num_lines < 1 || s->num_lines >= MAX_SHARED_LINES) {
> +        error_setg(errp,
> +                   "IRQ shared number of lines %d must be between 1 and %d",
> +                   s->num_lines, MAX_SHARED_LINES);
> +        return;
> +    }
> +
> +    qdev_init_gpio_in(dev, shared_irq_handler, s->num_lines);
> +}
> +
> +static const Property shared_irq_properties[] = {
> +    DEFINE_PROP_UINT8("num-lines", SharedIRQ, num_lines, 1),
> +};
> +
> +static const VMStateDescription shared_irq_vmstate = {
> +    .name = TYPE_SHARED_IRQ,
> +    .version_id = 1,
> +    .minimum_version_id = 1,
> +    .fields = (const VMStateField[]) {
> +        VMSTATE_UINT16(irq_states, SharedIRQ),
> +        VMSTATE_END_OF_LIST()
> +    },
> +};
> +
> +static void shared_irq_class_init(ObjectClass *klass, void *data)
> +{
> +    DeviceClass *dc = DEVICE_CLASS(klass);
> +
> +    /* No state to reset */
> +    device_class_set_props(dc, shared_irq_properties);
> +    dc->vmsd = &shared_irq_vmstate;
> +    dc->realize = shared_irq_realize;
> +
> +    /* Reason: Needs to be wired up to work */
> +    dc->user_creatable = false;
> +}
> +
> +static const TypeInfo shared_irq_types[] = {
> +    {
> +       .name = TYPE_SHARED_IRQ,
> +       .parent = TYPE_DEVICE,
> +       .instance_size = sizeof(SharedIRQ),
> +       .instance_init = shared_irq_init,
> +       .class_init = shared_irq_class_init,
> +    },
> +};
> +
> +DEFINE_TYPES(shared_irq_types)
> diff --git a/hw/core/Kconfig b/hw/core/Kconfig
> index d1bdf765ee..ddff977963 100644
> --- a/hw/core/Kconfig
> +++ b/hw/core/Kconfig
> @@ -32,6 +32,9 @@ config PLATFORM_BUS
> config REGISTER
>     bool
>
> +config SHARED_IRQ
> +    bool
> +
> config SPLIT_IRQ
>     bool
>
> diff --git a/hw/core/meson.build b/hw/core/meson.build
> index ce9dfa3f4b..6b5bdc8ec7 100644
> --- a/hw/core/meson.build
> +++ b/hw/core/meson.build
> @@ -21,6 +21,7 @@ system_ss.add(when: 'CONFIG_OR_IRQ', if_true: files('or-irq.c'))
> system_ss.add(when: 'CONFIG_PLATFORM_BUS', if_true: files('platform-bus.c'))
> system_ss.add(when: 'CONFIG_PTIMER', if_true: files('ptimer.c'))
> system_ss.add(when: 'CONFIG_REGISTER', if_true: files('register.c'))
> +system_ss.add(when: 'CONFIG_SHARED_IRQ', if_true: files('shared-irq.c'))
> system_ss.add(when: 'CONFIG_SPLIT_IRQ', if_true: files('split-irq.c'))
> system_ss.add(when: 'CONFIG_XILINX_AXI', if_true: files('stream.c'))
> system_ss.add(when: 'CONFIG_PLATFORM_BUS', if_true: files('sysbus-fdt.c'))
>
Bernhard Beschow Jan. 8, 2025, 2:26 p.m. UTC | #2 
Am 8. Januar 2025 09:25:28 UTC schrieb Bernhard Beschow <shentey@gmail.com>:
>Signed-off-by: Bernhard Beschow <shentey@gmail.com>
>---
> include/hw/core/shared-irq.h | 39 ++++++++++++++++
> hw/core/shared-irq.c         | 88 ++++++++++++++++++++++++++++++++++++
> hw/core/Kconfig              |  3 ++
> hw/core/meson.build          |  1 +
> 4 files changed, 131 insertions(+)
> create mode 100644 include/hw/core/shared-irq.h
> create mode 100644 hw/core/shared-irq.c
>
>diff --git a/include/hw/core/shared-irq.h b/include/hw/core/shared-irq.h
>new file mode 100644

As pointed out by David, this device is redundant to TYPE_OR_IRQ. I'll drop it in v2.

Best regards,
Bernhard

>index 0000000000..803c303dd0
>--- /dev/null
>+++ b/include/hw/core/shared-irq.h
>@@ -0,0 +1,39 @@
>+/*
>+ * IRQ sharing device.
>+ *
>+ * Copyright (c) 2025 Bernhard Beschow <shentey@gmail.com>
>+ *
>+ * SPDX-License-Identifier: GPL-2.0-or-later
>+ */
>+
>+/*
>+ * This is a simple device which has one GPIO output line and multiple GPIO
>+ * input lines. The output line is active if at least one of the input lines is.
>+ *
>+ * QEMU interface:
>+ *  + N unnamed GPIO inputs: the input lines
>+ *  + one unnamed GPIO output: the output line
>+ *  + QOM property "num-lines": sets the number of input lines
>+ */
>+#ifndef HW_SHARED_IRQ_H
>+#define HW_SHARED_IRQ_H
>+
>+#include "hw/sysbus.h"
>+#include "qom/object.h"
>+
>+#define TYPE_SHARED_IRQ "shared-irq"
>+
>+#define MAX_SHARED_LINES 16
>+
>+
>+OBJECT_DECLARE_SIMPLE_TYPE(SharedIRQ, SHARED_IRQ)
>+
>+struct SharedIRQ {
>+    DeviceState parent_obj;
>+
>+    qemu_irq out_irq;
>+    uint16_t irq_states;
>+    uint8_t num_lines;
>+};
>+
>+#endif
>diff --git a/hw/core/shared-irq.c b/hw/core/shared-irq.c
>new file mode 100644
>index 0000000000..b2a4ea4a66
>--- /dev/null
>+++ b/hw/core/shared-irq.c
>@@ -0,0 +1,88 @@
>+/*
>+ * IRQ sharing device.
>+ *
>+ * Copyright (c) 2025 Bernhard Beschow <shentey@gmail.com>
>+ *
>+ * SPDX-License-Identifier: GPL-2.0-or-later
>+ */
>+
>+#include "qemu/osdep.h"
>+#include "hw/core/shared-irq.h"
>+#include "hw/irq.h"
>+#include "hw/qdev-properties.h"
>+#include "qapi/error.h"
>+#include "migration/vmstate.h"
>+
>+static void shared_irq_handler(void *opaque, int n, int level)
>+{
>+    SharedIRQ *s = opaque;
>+    uint16_t mask = BIT(n);
>+
>+    if (level) {
>+        s->irq_states |= mask;
>+    } else {
>+        s->irq_states &= ~mask;
>+    }
>+
>+    qemu_set_irq(s->out_irq, !!s->irq_states);
>+}
>+
>+static void shared_irq_init(Object *obj)
>+{
>+    SharedIRQ *s = SHARED_IRQ(obj);
>+
>+    qdev_init_gpio_out(DEVICE(s), &s->out_irq, 1);
>+}
>+
>+static void shared_irq_realize(DeviceState *dev, Error **errp)
>+{
>+    SharedIRQ *s = SHARED_IRQ(dev);
>+
>+    if (s->num_lines < 1 || s->num_lines >= MAX_SHARED_LINES) {
>+        error_setg(errp,
>+                   "IRQ shared number of lines %d must be between 1 and %d",
>+                   s->num_lines, MAX_SHARED_LINES);
>+        return;
>+    }
>+
>+    qdev_init_gpio_in(dev, shared_irq_handler, s->num_lines);
>+}
>+
>+static const Property shared_irq_properties[] = {
>+    DEFINE_PROP_UINT8("num-lines", SharedIRQ, num_lines, 1),
>+};
>+
>+static const VMStateDescription shared_irq_vmstate = {
>+    .name = TYPE_SHARED_IRQ,
>+    .version_id = 1,
>+    .minimum_version_id = 1,
>+    .fields = (const VMStateField[]) {
>+        VMSTATE_UINT16(irq_states, SharedIRQ),
>+        VMSTATE_END_OF_LIST()
>+    },
>+};
>+
>+static void shared_irq_class_init(ObjectClass *klass, void *data)
>+{
>+    DeviceClass *dc = DEVICE_CLASS(klass);
>+
>+    /* No state to reset */
>+    device_class_set_props(dc, shared_irq_properties);
>+    dc->vmsd = &shared_irq_vmstate;
>+    dc->realize = shared_irq_realize;
>+
>+    /* Reason: Needs to be wired up to work */
>+    dc->user_creatable = false;
>+}
>+
>+static const TypeInfo shared_irq_types[] = {
>+    {
>+       .name = TYPE_SHARED_IRQ,
>+       .parent = TYPE_DEVICE,
>+       .instance_size = sizeof(SharedIRQ),
>+       .instance_init = shared_irq_init,
>+       .class_init = shared_irq_class_init,
>+    },
>+};
>+
>+DEFINE_TYPES(shared_irq_types)
>diff --git a/hw/core/Kconfig b/hw/core/Kconfig
>index d1bdf765ee..ddff977963 100644
>--- a/hw/core/Kconfig
>+++ b/hw/core/Kconfig
>@@ -32,6 +32,9 @@ config PLATFORM_BUS
> config REGISTER
>     bool
> 
>+config SHARED_IRQ
>+    bool
>+
> config SPLIT_IRQ
>     bool
> 
>diff --git a/hw/core/meson.build b/hw/core/meson.build
>index ce9dfa3f4b..6b5bdc8ec7 100644
>--- a/hw/core/meson.build
>+++ b/hw/core/meson.build
>@@ -21,6 +21,7 @@ system_ss.add(when: 'CONFIG_OR_IRQ', if_true: files('or-irq.c'))
> system_ss.add(when: 'CONFIG_PLATFORM_BUS', if_true: files('platform-bus.c'))
> system_ss.add(when: 'CONFIG_PTIMER', if_true: files('ptimer.c'))
> system_ss.add(when: 'CONFIG_REGISTER', if_true: files('register.c'))
>+system_ss.add(when: 'CONFIG_SHARED_IRQ', if_true: files('shared-irq.c'))
> system_ss.add(when: 'CONFIG_SPLIT_IRQ', if_true: files('split-irq.c'))
> system_ss.add(when: 'CONFIG_XILINX_AXI', if_true: files('stream.c'))
> system_ss.add(when: 'CONFIG_PLATFORM_BUS', if_true: files('sysbus-fdt.c'))
Bernhard Beschow Jan. 9, 2025, 9:14 a.m. UTC | #3 
Am 8. Januar 2025 13:53:02 UTC schrieb BALATON Zoltan <balaton@eik.bme.hu>:
>On Wed, 8 Jan 2025, Bernhard Beschow wrote:
>> Signed-off-by: Bernhard Beschow <shentey@gmail.com>
>> ---
>> include/hw/core/shared-irq.h | 39 ++++++++++++++++
>> hw/core/shared-irq.c         | 88 ++++++++++++++++++++++++++++++++++++
>> hw/core/Kconfig              |  3 ++
>> hw/core/meson.build          |  1 +
>> 4 files changed, 131 insertions(+)
>> create mode 100644 include/hw/core/shared-irq.h
>> create mode 100644 hw/core/shared-irq.c
>> 
>> diff --git a/include/hw/core/shared-irq.h b/include/hw/core/shared-irq.h
>> new file mode 100644
>> index 0000000000..803c303dd0
>> --- /dev/null
>> +++ b/include/hw/core/shared-irq.h
>> @@ -0,0 +1,39 @@
>> +/*
>> + * IRQ sharing device.
>> + *
>> + * Copyright (c) 2025 Bernhard Beschow <shentey@gmail.com>
>> + *
>> + * SPDX-License-Identifier: GPL-2.0-or-later
>> + */
>> +
>> +/*
>> + * This is a simple device which has one GPIO output line and multiple GPIO
>> + * input lines. The output line is active if at least one of the input lines is.
>
>How is this different from TYPE_OR_IRQ. Also or-irq.h is in include/hw/or-irq.h not in include/hw/core/ where split-irq.h is

I missed exactly that.

> so maybe these could all be moved to one place for consistency? Or-irq also has a reset method, do you need one in this device?

TYPE_OR_IRQ should be used instead. The next iteration will use it and this patch will be dropped.

Best regards,
Bernhard

>
>Regards,
>BALATON Zoltan
>
>> + *
>> + * QEMU interface:
>> + *  + N unnamed GPIO inputs: the input lines
>> + *  + one unnamed GPIO output: the output line
>> + *  + QOM property "num-lines": sets the number of input lines
>> + */
>> +#ifndef HW_SHARED_IRQ_H
>> +#define HW_SHARED_IRQ_H
>> +
>> +#include "hw/sysbus.h"
>> +#include "qom/object.h"
>> +
>> +#define TYPE_SHARED_IRQ "shared-irq"
>> +
>> +#define MAX_SHARED_LINES 16
>> +
>> +
>> +OBJECT_DECLARE_SIMPLE_TYPE(SharedIRQ, SHARED_IRQ)
>> +
>> +struct SharedIRQ {
>> +    DeviceState parent_obj;
>> +
>> +    qemu_irq out_irq;
>> +    uint16_t irq_states;
>> +    uint8_t num_lines;
>> +};
>> +
>> +#endif
>> diff --git a/hw/core/shared-irq.c b/hw/core/shared-irq.c
>> new file mode 100644
>> index 0000000000..b2a4ea4a66
>> --- /dev/null
>> +++ b/hw/core/shared-irq.c
>> @@ -0,0 +1,88 @@
>> +/*
>> + * IRQ sharing device.
>> + *
>> + * Copyright (c) 2025 Bernhard Beschow <shentey@gmail.com>
>> + *
>> + * SPDX-License-Identifier: GPL-2.0-or-later
>> + */
>> +
>> +#include "qemu/osdep.h"
>> +#include "hw/core/shared-irq.h"
>> +#include "hw/irq.h"
>> +#include "hw/qdev-properties.h"
>> +#include "qapi/error.h"
>> +#include "migration/vmstate.h"
>> +
>> +static void shared_irq_handler(void *opaque, int n, int level)
>> +{
>> +    SharedIRQ *s = opaque;
>> +    uint16_t mask = BIT(n);
>> +
>> +    if (level) {
>> +        s->irq_states |= mask;
>> +    } else {
>> +        s->irq_states &= ~mask;
>> +    }
>> +
>> +    qemu_set_irq(s->out_irq, !!s->irq_states);
>> +}
>> +
>> +static void shared_irq_init(Object *obj)
>> +{
>> +    SharedIRQ *s = SHARED_IRQ(obj);
>> +
>> +    qdev_init_gpio_out(DEVICE(s), &s->out_irq, 1);
>> +}
>> +
>> +static void shared_irq_realize(DeviceState *dev, Error **errp)
>> +{
>> +    SharedIRQ *s = SHARED_IRQ(dev);
>> +
>> +    if (s->num_lines < 1 || s->num_lines >= MAX_SHARED_LINES) {
>> +        error_setg(errp,
>> +                   "IRQ shared number of lines %d must be between 1 and %d",
>> +                   s->num_lines, MAX_SHARED_LINES);
>> +        return;
>> +    }
>> +
>> +    qdev_init_gpio_in(dev, shared_irq_handler, s->num_lines);
>> +}
>> +
>> +static const Property shared_irq_properties[] = {
>> +    DEFINE_PROP_UINT8("num-lines", SharedIRQ, num_lines, 1),
>> +};
>> +
>> +static const VMStateDescription shared_irq_vmstate = {
>> +    .name = TYPE_SHARED_IRQ,
>> +    .version_id = 1,
>> +    .minimum_version_id = 1,
>> +    .fields = (const VMStateField[]) {
>> +        VMSTATE_UINT16(irq_states, SharedIRQ),
>> +        VMSTATE_END_OF_LIST()
>> +    },
>> +};
>> +
>> +static void shared_irq_class_init(ObjectClass *klass, void *data)
>> +{
>> +    DeviceClass *dc = DEVICE_CLASS(klass);
>> +
>> +    /* No state to reset */
>> +    device_class_set_props(dc, shared_irq_properties);
>> +    dc->vmsd = &shared_irq_vmstate;
>> +    dc->realize = shared_irq_realize;
>> +
>> +    /* Reason: Needs to be wired up to work */
>> +    dc->user_creatable = false;
>> +}
>> +
>> +static const TypeInfo shared_irq_types[] = {
>> +    {
>> +       .name = TYPE_SHARED_IRQ,
>> +       .parent = TYPE_DEVICE,
>> +       .instance_size = sizeof(SharedIRQ),
>> +       .instance_init = shared_irq_init,
>> +       .class_init = shared_irq_class_init,
>> +    },
>> +};
>> +
>> +DEFINE_TYPES(shared_irq_types)
>> diff --git a/hw/core/Kconfig b/hw/core/Kconfig
>> index d1bdf765ee..ddff977963 100644
>> --- a/hw/core/Kconfig
>> +++ b/hw/core/Kconfig
>> @@ -32,6 +32,9 @@ config PLATFORM_BUS
>> config REGISTER
>>     bool
>> 
>> +config SHARED_IRQ
>> +    bool
>> +
>> config SPLIT_IRQ
>>     bool
>> 
>> diff --git a/hw/core/meson.build b/hw/core/meson.build
>> index ce9dfa3f4b..6b5bdc8ec7 100644
>> --- a/hw/core/meson.build
>> +++ b/hw/core/meson.build
>> @@ -21,6 +21,7 @@ system_ss.add(when: 'CONFIG_OR_IRQ', if_true: files('or-irq.c'))
>> system_ss.add(when: 'CONFIG_PLATFORM_BUS', if_true: files('platform-bus.c'))
>> system_ss.add(when: 'CONFIG_PTIMER', if_true: files('ptimer.c'))
>> system_ss.add(when: 'CONFIG_REGISTER', if_true: files('register.c'))
>> +system_ss.add(when: 'CONFIG_SHARED_IRQ', if_true: files('shared-irq.c'))
>> system_ss.add(when: 'CONFIG_SPLIT_IRQ', if_true: files('split-irq.c'))
>> system_ss.add(when: 'CONFIG_XILINX_AXI', if_true: files('stream.c'))
>> system_ss.add(when: 'CONFIG_PLATFORM_BUS', if_true: files('sysbus-fdt.c'))
>>
diff mbox series

Patch

diff --git a/include/hw/core/shared-irq.h b/include/hw/core/shared-irq.h
new file mode 100644
index 0000000000..803c303dd0
--- /dev/null
+++ b/include/hw/core/shared-irq.h
@@ -0,0 +1,39 @@ 
+/*
+ * IRQ sharing device.
+ *
+ * Copyright (c) 2025 Bernhard Beschow <shentey@gmail.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+/*
+ * This is a simple device which has one GPIO output line and multiple GPIO
+ * input lines. The output line is active if at least one of the input lines is.
+ *
+ * QEMU interface:
+ *  + N unnamed GPIO inputs: the input lines
+ *  + one unnamed GPIO output: the output line
+ *  + QOM property "num-lines": sets the number of input lines
+ */
+#ifndef HW_SHARED_IRQ_H
+#define HW_SHARED_IRQ_H
+
+#include "hw/sysbus.h"
+#include "qom/object.h"
+
+#define TYPE_SHARED_IRQ "shared-irq"
+
+#define MAX_SHARED_LINES 16
+
+
+OBJECT_DECLARE_SIMPLE_TYPE(SharedIRQ, SHARED_IRQ)
+
+struct SharedIRQ {
+    DeviceState parent_obj;
+
+    qemu_irq out_irq;
+    uint16_t irq_states;
+    uint8_t num_lines;
+};
+
+#endif
diff --git a/hw/core/shared-irq.c b/hw/core/shared-irq.c
new file mode 100644
index 0000000000..b2a4ea4a66
--- /dev/null
+++ b/hw/core/shared-irq.c
@@ -0,0 +1,88 @@ 
+/*
+ * IRQ sharing device.
+ *
+ * Copyright (c) 2025 Bernhard Beschow <shentey@gmail.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "hw/core/shared-irq.h"
+#include "hw/irq.h"
+#include "hw/qdev-properties.h"
+#include "qapi/error.h"
+#include "migration/vmstate.h"
+
+static void shared_irq_handler(void *opaque, int n, int level)
+{
+    SharedIRQ *s = opaque;
+    uint16_t mask = BIT(n);
+
+    if (level) {
+        s->irq_states |= mask;
+    } else {
+        s->irq_states &= ~mask;
+    }
+
+    qemu_set_irq(s->out_irq, !!s->irq_states);
+}
+
+static void shared_irq_init(Object *obj)
+{
+    SharedIRQ *s = SHARED_IRQ(obj);
+
+    qdev_init_gpio_out(DEVICE(s), &s->out_irq, 1);
+}
+
+static void shared_irq_realize(DeviceState *dev, Error **errp)
+{
+    SharedIRQ *s = SHARED_IRQ(dev);
+
+    if (s->num_lines < 1 || s->num_lines >= MAX_SHARED_LINES) {
+        error_setg(errp,
+                   "IRQ shared number of lines %d must be between 1 and %d",
+                   s->num_lines, MAX_SHARED_LINES);
+        return;
+    }
+
+    qdev_init_gpio_in(dev, shared_irq_handler, s->num_lines);
+}
+
+static const Property shared_irq_properties[] = {
+    DEFINE_PROP_UINT8("num-lines", SharedIRQ, num_lines, 1),
+};
+
+static const VMStateDescription shared_irq_vmstate = {
+    .name = TYPE_SHARED_IRQ,
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (const VMStateField[]) {
+        VMSTATE_UINT16(irq_states, SharedIRQ),
+        VMSTATE_END_OF_LIST()
+    },
+};
+
+static void shared_irq_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    /* No state to reset */
+    device_class_set_props(dc, shared_irq_properties);
+    dc->vmsd = &shared_irq_vmstate;
+    dc->realize = shared_irq_realize;
+
+    /* Reason: Needs to be wired up to work */
+    dc->user_creatable = false;
+}
+
+static const TypeInfo shared_irq_types[] = {
+    {
+       .name = TYPE_SHARED_IRQ,
+       .parent = TYPE_DEVICE,
+       .instance_size = sizeof(SharedIRQ),
+       .instance_init = shared_irq_init,
+       .class_init = shared_irq_class_init,
+    },
+};
+
+DEFINE_TYPES(shared_irq_types)
diff --git a/hw/core/Kconfig b/hw/core/Kconfig
index d1bdf765ee..ddff977963 100644
--- a/hw/core/Kconfig
+++ b/hw/core/Kconfig
@@ -32,6 +32,9 @@  config PLATFORM_BUS
 config REGISTER
     bool
 
+config SHARED_IRQ
+    bool
+
 config SPLIT_IRQ
     bool
 
diff --git a/hw/core/meson.build b/hw/core/meson.build
index ce9dfa3f4b..6b5bdc8ec7 100644
--- a/hw/core/meson.build
+++ b/hw/core/meson.build
@@ -21,6 +21,7 @@  system_ss.add(when: 'CONFIG_OR_IRQ', if_true: files('or-irq.c'))
 system_ss.add(when: 'CONFIG_PLATFORM_BUS', if_true: files('platform-bus.c'))
 system_ss.add(when: 'CONFIG_PTIMER', if_true: files('ptimer.c'))
 system_ss.add(when: 'CONFIG_REGISTER', if_true: files('register.c'))
+system_ss.add(when: 'CONFIG_SHARED_IRQ', if_true: files('shared-irq.c'))
 system_ss.add(when: 'CONFIG_SPLIT_IRQ', if_true: files('split-irq.c'))
 system_ss.add(when: 'CONFIG_XILINX_AXI', if_true: files('stream.c'))
 system_ss.add(when: 'CONFIG_PLATFORM_BUS', if_true: files('sysbus-fdt.c'))