[Qemu-devel] Re: [PATCH 1/3] Add rtc reset function.

[Jan Kiszka <jan.kiszka@siemens.com>]

Gleb Natapov wrote:
> On reset:
> Periodic Interrupt Enable (PIE) bit is cleared to zero
> Alarm Interrupt Enable (AIE) bit is cleared to zero
> Update ended Interrupt Flag (UF) bit is cleared to zero
> Interrupt Request status Flag (IRQF) bit is cleared to zero
> Periodic Interrupt Flag (PF) bit is cleared to zero
> Alarm Interrupt Flag (AF) bit is cleared to zero
> Square Wave output Enable (SQWE) zero
> 
> Signed-off-by: Gleb Natapov <gleb@redhat.com>
> ---
>  hw/mc146818rtc.c |   19 +++++++++++++++++++
>  1 files changed, 19 insertions(+), 0 deletions(-)
> 
> diff --git a/hw/mc146818rtc.c b/hw/mc146818rtc.c
> index 888b85a..98a2273 100644
> --- a/hw/mc146818rtc.c
> +++ b/hw/mc146818rtc.c
> @@ -568,6 +568,22 @@ static int rtc_load_td(QEMUFile *f, void *opaque, int version_id)
>  }
>  #endif
>  
> +static void rtc_reset(void *opaque)
> +{
> +    RTCState *s = opaque;
> +
> +    /* clear PIE,AIE,SQWE on reset */
> +    s->cmos_data[RTC_REG_B] &= ~((1<<6) | (1<<5) | (1<<3));
> +
> +    /* clear UF,IRQF,PF,AF on reset */
> +    s->cmos_data[RTC_REG_C] &= ~((1<<4) | (1<<7) | (1<<6) | (1<<5));

Didn't check what the rest of this file does, but maybe it's a chance to
give those bits names, ie. #define something.

> +
> +#ifdef TARGET_I386
> +    if (rtc_td_hack)
> +	    s->irq_coalesced = 0;
> +#endif
> +}
> +
>  RTCState *rtc_init_sqw(int base, qemu_irq irq, qemu_irq sqw_irq, int base_year)
>  {
>      RTCState *s;
> @@ -606,6 +622,8 @@ RTCState *rtc_init_sqw(int base, qemu_irq irq, qemu_irq sqw_irq, int base_year)
>      if (rtc_td_hack)
>          register_savevm("mc146818rtc-td", base, 1, rtc_save_td, rtc_load_td, s);
>  #endif
> +    qemu_register_reset(rtc_reset, 0, s);
> +
>      return s;
>  }
>  
> @@ -721,5 +739,6 @@ RTCState *rtc_mm_init(target_phys_addr_t base, int it_shift, qemu_irq irq,
>      if (rtc_td_hack)
>          register_savevm("mc146818rtc-td", base, 1, rtc_save_td, rtc_load_td, s);
>  #endif
> +    qemu_register_reset(rtc_reset, 0, s);
>      return s;
>  }

Jan

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