Re: [PATCH v3 2/2] hw/rtc/mc146818rtc: Convert to 3-phase reset (Resettable interface)

["Edgar E. Iglesias" <edgar.iglesias@gmail.com>]

On Sun, May 02, 2021 at 06:39:31PM +0200, Philippe Mathieu-Daudé wrote:
> TYPE_MC146818_RTC is an ISA device, so its DeviceClass::reset()
> handler is called automatically when its qbus parent is reset
> (we don't need to register it manually).
> 
> We have 2 reset() methods: a generic one and the qdev one.
> Merge them into a reset_enter handler (keeping the IRQ lowering
> to a reset_hold one), and remove the qemu_register_reset() call.

Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>


> 
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
>  hw/rtc/mc146818rtc.c | 42 ++++++++++++++++++++++--------------------
>  1 file changed, 22 insertions(+), 20 deletions(-)
> 
> diff --git a/hw/rtc/mc146818rtc.c b/hw/rtc/mc146818rtc.c
> index 5d0fcacd0c0..836c3691706 100644
> --- a/hw/rtc/mc146818rtc.c
> +++ b/hw/rtc/mc146818rtc.c
> @@ -872,22 +872,6 @@ static void rtc_notify_suspend(Notifier *notifier, void *data)
>      rtc_set_memory(ISA_DEVICE(s), 0xF, 0xFE);
>  }
>  
> -static void rtc_reset(void *opaque)
> -{
> -    RTCState *s = opaque;
> -
> -    s->cmos_data[RTC_REG_B] &= ~(REG_B_PIE | REG_B_AIE | REG_B_SQWE);
> -    s->cmos_data[RTC_REG_C] &= ~(REG_C_UF | REG_C_IRQF | REG_C_PF | REG_C_AF);
> -    check_update_timer(s);
> -
> -    qemu_irq_lower(s->irq);
> -
> -    if (s->lost_tick_policy == LOST_TICK_POLICY_SLEW) {
> -        s->irq_coalesced = 0;
> -        s->irq_reinject_on_ack_count = 0;
> -    }
> -}
> -
>  static const MemoryRegionOps cmos_ops = {
>      .read = cmos_ioport_read,
>      .write = cmos_ioport_write,
> @@ -962,7 +946,6 @@ static void rtc_realizefn(DeviceState *dev, Error **errp)
>      memory_region_add_coalescing(&s->coalesced_io, 0, 1);
>  
>      qdev_set_legacy_instance_id(dev, RTC_ISA_BASE, 3);
> -    qemu_register_reset(rtc_reset, s);
>  
>      object_property_add_tm(OBJECT(s), "date", rtc_get_date);
>  
> @@ -998,15 +981,32 @@ static Property mc146818rtc_properties[] = {
>      DEFINE_PROP_END_OF_LIST(),
>  };
>  
> -static void rtc_resetdev(DeviceState *d)
> +static void rtc_reset_enter(Object *obj, ResetType type)
>  {
> -    RTCState *s = MC146818_RTC(d);
> +    RTCState *s = MC146818_RTC(obj);
>  
>      /* Reason: VM do suspend self will set 0xfe
>       * Reset any values other than 0xfe(Guest suspend case) */
>      if (s->cmos_data[0x0f] != 0xfe) {
>          s->cmos_data[0x0f] = 0x00;
>      }
> +
> +    s->cmos_data[RTC_REG_B] &= ~(REG_B_PIE | REG_B_AIE | REG_B_SQWE);
> +    s->cmos_data[RTC_REG_C] &= ~(REG_C_UF | REG_C_IRQF | REG_C_PF | REG_C_AF);
> +    check_update_timer(s);
> +
> +
> +    if (s->lost_tick_policy == LOST_TICK_POLICY_SLEW) {
> +        s->irq_coalesced = 0;
> +        s->irq_reinject_on_ack_count = 0;
> +    }
> +}
> +
> +static void rtc_reset_hold(Object *obj)
> +{
> +    RTCState *s = MC146818_RTC(obj);
> +
> +    qemu_irq_lower(s->irq);
>  }
>  
>  static void rtc_build_aml(ISADevice *isadev, Aml *scope)
> @@ -1033,11 +1033,13 @@ static void rtc_build_aml(ISADevice *isadev, Aml *scope)
>  static void rtc_class_initfn(ObjectClass *klass, void *data)
>  {
>      DeviceClass *dc = DEVICE_CLASS(klass);
> +    ResettableClass *rc = RESETTABLE_CLASS(klass);
>      ISADeviceClass *isa = ISA_DEVICE_CLASS(klass);
>  
>      dc->realize = rtc_realizefn;
> -    dc->reset = rtc_resetdev;
>      dc->vmsd = &vmstate_rtc;
> +    rc->phases.enter = rtc_reset_enter;
> +    rc->phases.hold = rtc_reset_hold;
>      isa->build_aml = rtc_build_aml;
>      device_class_set_props(dc, mc146818rtc_properties);
>  }
> -- 
> 2.26.3
>