Re: [PATCH v2 for-8.0] hw/rtc/mc146818rtc: Make this rtc device target independent

[Thomas Huth]

On 10/12/2022 14.48, Mark Cave-Ayland wrote:
> On 09/12/2022 11:15, Thomas Huth wrote:
>
> > The only reason for this code being target dependent is the apic-related
> > code in rtc_policy_slew_deliver_irq(). Since these apic functions are rather
> > simple, we can easily move them into a new, separate file (apic_irqcount.c)
> > which will always be compiled and linked if either APIC or the mc146818 
> > device
> > are required. This way we can get rid of the #ifdef TARGET_I386 switches in
> > mc146818rtc.c and declare it in the softmmu_ss instead of specific_ss, so
> > that the code only gets compiled once for all targets.
[...]
> > diff --git a/hw/rtc/mc146818rtc.c b/hw/rtc/mc146818rtc.c
> > index 1ebb412479..afb1f385a3 100644
> > --- a/hw/rtc/mc146818rtc.c
> > +++ b/hw/rtc/mc146818rtc.c
> > @@ -43,11 +43,7 @@
> >   #include "qapi/qapi-events-misc.h"
> >   #include "qapi/visitor.h"
> >   #include "hw/rtc/mc146818rtc_regs.h"
> > -
> > -#ifdef TARGET_I386
> > -#include "qapi/qapi-commands-misc-target.h"
> >   #include "hw/i386/apic.h"
> > -#endif
> >   //#define DEBUG_CMOS
> >   //#define DEBUG_COALESCED
> > @@ -112,7 +108,6 @@ static void rtc_coalesced_timer_update(RTCState *s)
> >   static QLIST_HEAD(, RTCState) rtc_devices =
> >       QLIST_HEAD_INITIALIZER(rtc_devices);
> > -#ifdef TARGET_I386
> >   void qmp_rtc_reset_reinjection(Error **errp)
> >   {
> >       RTCState *s;
> > @@ -145,13 +140,6 @@ static void rtc_coalesced_timer(void *opaque)
> >       rtc_coalesced_timer_update(s);
> >   }
> > -#else
> > -static bool rtc_policy_slew_deliver_irq(RTCState *s)
> > -{
> > -    assert(0);
> > -    return false;
> > -}
> > -#endif
> >   static uint32_t rtc_periodic_clock_ticks(RTCState *s)
> >   {
> > @@ -922,14 +910,15 @@ static void rtc_realizefn(DeviceState *dev, Error 
> > **errp)
> >       rtc_set_date_from_host(isadev);
> >       switch (s->lost_tick_policy) {
> > -#ifdef TARGET_I386
> > -    case LOST_TICK_POLICY_SLEW:
> > -        s->coalesced_timer =
> > -            timer_new_ns(rtc_clock, rtc_coalesced_timer, s);
> > -        break;
> > -#endif
> >       case LOST_TICK_POLICY_DISCARD:
> >           break;
> > +    case LOST_TICK_POLICY_SLEW:
> > +        /* Slew tick policy is only available if the machine has an APIC */
> > +        if (object_resolve_path_type("", "apic-common", NULL) != NULL) {
>
> Hmmm. These days we should be using TYPE_APIC_COMMON, however it seems that 
> APICCommonState is defined in apic_internal.h rather than apic.h which seems 
> wrong (it prevents you from passing an APICCommonState as an object link 
> property as well as from using TYPE_APIC_COMMON).
>
> > +            s->coalesced_timer = timer_new_ns(rtc_clock, 
> > rtc_coalesced_timer, s);
> > +            break;
> > +        }
> > +        /* fallthrough */
> >       default:
> >           error_setg(errp, "Invalid lost tick policy.");
> >           return;
> > diff --git a/hw/intc/meson.build b/hw/intc/meson.build
> > index bcbf22ff51..036ad1936b 100644
> > --- a/hw/intc/meson.build
> > +++ b/hw/intc/meson.build
> > @@ -25,8 +25,12 @@ softmmu_ss.add(when: 'CONFIG_XILINX', if_true: 
> > files('xilinx_intc.c'))
> >   softmmu_ss.add(when: 'CONFIG_XLNX_ZYNQMP', if_true: 
> > files('xlnx-zynqmp-ipi.c'))
> >   softmmu_ss.add(when: 'CONFIG_XLNX_ZYNQMP_PMU', if_true: 
> > files('xlnx-pmu-iomod-intc.c'))
> > -specific_ss.add(when: 'CONFIG_ALLWINNER_A10_PIC', if_true: 
> > files('allwinner-a10-pic.c'))
> > +if config_all_devices.has_key('CONFIG_APIC') or 
> > config_all_devices.has_key('CONFIG_MC146818RTC')
> > +    softmmu_ss.add(files('apic_irqcount.c'))
> > +endif
> >   specific_ss.add(when: 'CONFIG_APIC', if_true: files('apic.c', 
> > 'apic_common.c'))
> > +
> > +specific_ss.add(when: 'CONFIG_ALLWINNER_A10_PIC', if_true: 
> > files('allwinner-a10-pic.c'))
> >   specific_ss.add(when: 'CONFIG_ARM_GIC', if_true: 
> > files('arm_gicv3_cpuif_common.c'))
> >   specific_ss.add(when: 'CONFIG_ARM_GICV3_TCG', if_true: 
> > files('arm_gicv3_cpuif.c'))
> >   specific_ss.add(when: 'CONFIG_ARM_GIC_KVM', if_true: 
> > files('arm_gic_kvm.c'))
> > diff --git a/hw/rtc/meson.build b/hw/rtc/meson.build
> > index dc33973384..34a4d316fa 100644
> > --- a/hw/rtc/meson.build
> > +++ b/hw/rtc/meson.build
> > @@ -13,5 +13,4 @@ softmmu_ss.add(when: 'CONFIG_ASPEED_SOC', if_true: 
> > files('aspeed_rtc.c'))
> >   softmmu_ss.add(when: 'CONFIG_GOLDFISH_RTC', if_true: 
> > files('goldfish_rtc.c'))
> >   softmmu_ss.add(when: 'CONFIG_LS7A_RTC', if_true: files('ls7a_rtc.c'))
> >   softmmu_ss.add(when: 'CONFIG_ALLWINNER_H3', if_true: 
> > files('allwinner-rtc.c'))
> > -
> > -specific_ss.add(when: 'CONFIG_MC146818RTC', if_true: files('mc146818rtc.c'))
> > +softmmu_ss.add(when: 'CONFIG_MC146818RTC', if_true: files('mc146818rtc.c'))
>
> Fixing up the headers to allow TYPE_APIC_COMMON rather than hard-coding 
> "apic-common" would be my preference, however there is a lot of legacy code 
> here and the fear would be that once you pull on that string then more will 
> keep unravelling... 

I gave it a try now and it seems to be OK to move TYPE_APIC_COMMON from 
apic_internal.h to apic.h ... so I'll add that change and send a v3.

Thanks!

 Thomas