On 5/28/20 1:04 PM, Markus Armbruster wrote:
> These devices are optional, and enabled by property "enable-bitband".
> armv7m_instance_init() creates them unconditionally, because the
> property has not been set then. armv7m_realize() realizes them only
> when the property is true. Works, although it leaves unrealized
> devices hanging around in the QOM composition tree. Affects machines
> microbit, mps2-an505, mps2-an521, musca-a, and musca-b1.
>
> Delete the unused devices by making armv7m_realize() unparent them.
> Visible in "info qom-tree"; here's the change for microbit:
>
> /machine (microbit-machine)
>/microbit.twi (microbit.i2c)
> /microbit.twi[0] (qemu:memory-region)
>/nrf51 (nrf51-soc)
> /armv6m (armv7m)
>/armv7m-container[0] (qemu:memory-region)
> - /bitband[0] (ARM,bitband-memory)
> -/bitband[0] (qemu:memory-region)
> - /bitband[1] (ARM,bitband-memory)
> -/bitband[0] (qemu:memory-region)
>/cpu (cortex-m0-arm-cpu)
>
> Cc: Peter Maydell
> Cc: qemu-...@nongnu.org
> Signed-off-by: Markus Armbruster
Reviewed-by: Philippe Mathieu-Daudé
> ---
> hw/arm/armv7m.c | 6 --
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/hw/arm/armv7m.c b/hw/arm/armv7m.c
> index 7da57f56d3..f930619f53 100644
> --- a/hw/arm/armv7m.c
> +++ b/hw/arm/armv7m.c
> @@ -245,8 +245,8 @@ static void armv7m_realize(DeviceState *dev, Error **errp)
> memory_region_add_subregion(>container, 0xe000e000,
> sysbus_mmio_get_region(sbd, 0));
>
> -if (s->enable_bitband) {
> -for (i = 0; i < ARRAY_SIZE(s->bitband); i++) {
> +for (i = 0; i < ARRAY_SIZE(s->bitband); i++) {
> +if (s->enable_bitband) {
> Object *obj = OBJECT(>bitband[i]);
> SysBusDevice *sbd = SYS_BUS_DEVICE(>bitband[i]);
>
> @@ -265,6 +265,8 @@ static void armv7m_realize(DeviceState *dev, Error **errp)
>
> memory_region_add_subregion(>container,
> bitband_output_addr[i],
> sysbus_mmio_get_region(sbd, 0));
> +} else {
> +object_unparent(OBJECT(>bitband[i]));
> }
> }
> }
>
