Re: [PATCH 4/8] hw/watchdog/milkymist-sysctl.c: Switch to transaction-based ptimer API

[Philippe Mathieu-Daudé]

On 10/17/19 3:29 PM, Peter Maydell wrote:
> Switch the milkymist-sysctl code away from bottom-half based
> ptimers to the new transaction-based ptimer API.  This just requires
> adding begin/commit calls around the various places that modify the
> ptimer state, and using the new ptimer_init() function to create the
> timer.
>
> Signed-off-by: Peter Maydell <address@hidden>
> ---
>   hw/timer/milkymist-sysctl.c | 25 ++++++++++++++++++-------
>   1 file changed, 18 insertions(+), 7 deletions(-)
>
> diff --git a/hw/timer/milkymist-sysctl.c b/hw/timer/milkymist-sysctl.c
> index 5193c038501..66f86541114 100644
> --- a/hw/timer/milkymist-sysctl.c
> +++ b/hw/timer/milkymist-sysctl.c
> @@ -31,7 +31,6 @@
>   #include "hw/ptimer.h"
>   #include "hw/qdev-properties.h"
>   #include "qemu/error-report.h"
> -#include "qemu/main-loop.h"
>   #include "qemu/module.h"
>   
>   enum {
> @@ -71,8 +70,6 @@ struct MilkymistSysctlState {
>   
>       MemoryRegion regs_region;
>   
> -    QEMUBH *bh0;
> -    QEMUBH *bh1;
>       ptimer_state *ptimer0;
>       ptimer_state *ptimer1;
>   
> @@ -161,14 +158,19 @@ static void sysctl_write(void *opaque, hwaddr addr, uint64_t value,
>           s->regs[addr] = value;
>           break;
>       case R_TIMER0_COMPARE:
> +        ptimer_transaction_begin(s->ptimer0);
>           ptimer_set_limit(s->ptimer0, value, 0);
>           s->regs[addr] = value;
> +        ptimer_transaction_commit(s->ptimer0);
>           break;
>       case R_TIMER1_COMPARE:
> +        ptimer_transaction_begin(s->ptimer1);
>           ptimer_set_limit(s->ptimer1, value, 0);
>           s->regs[addr] = value;
> +        ptimer_transaction_commit(s->ptimer1);
>           break;
>       case R_TIMER0_CONTROL:
> +        ptimer_transaction_begin(s->ptimer0);
>           s->regs[addr] = value;
>           if (s->regs[R_TIMER0_CONTROL] & CTRL_ENABLE) {
>               trace_milkymist_sysctl_start_timer0();
> @@ -179,8 +181,10 @@ static void sysctl_write(void *opaque, hwaddr addr, 
> uint64_t value,
>               trace_milkymist_sysctl_stop_timer0();
>               ptimer_stop(s->ptimer0);
>           }
> +        ptimer_transaction_commit(s->ptimer0);
>           break;
>       case R_TIMER1_CONTROL:
> +        ptimer_transaction_begin(s->ptimer0);

Copy/paste error I suppose, ptimer1 :)

>           s->regs[addr] = value;
>           if (s->regs[R_TIMER1_CONTROL] & CTRL_ENABLE) {
>               trace_milkymist_sysctl_start_timer1();
> @@ -191,6 +195,7 @@ static void sysctl_write(void *opaque, hwaddr addr, 
> uint64_t value,
>               trace_milkymist_sysctl_stop_timer1();
>               ptimer_stop(s->ptimer1);
>           }
> +        ptimer_transaction_commit(s->ptimer0);

Ditto.

With it fixed:
Reviewed-by: Philippe Mathieu-Daudé <address@hidden>

>           break;
>       case R_ICAP:
>           sysctl_icap_write(s, value);
> @@ -263,8 +268,12 @@ static void milkymist_sysctl_reset(DeviceState *d)
>           s->regs[i] = 0;
>       }
>   
> +    ptimer_transaction_begin(s->ptimer0);
>       ptimer_stop(s->ptimer0);
> +    ptimer_transaction_commit(s->ptimer0);
> +    ptimer_transaction_begin(s->ptimer1);
>       ptimer_stop(s->ptimer1);
> +    ptimer_transaction_commit(s->ptimer1);
>   
>       /* defaults */
>       s->regs[R_ICAP] = ICAP_READY;
> @@ -292,13 +301,15 @@ static void milkymist_sysctl_realize(DeviceState *dev, 
> Error **errp)
>   {
>       MilkymistSysctlState *s = MILKYMIST_SYSCTL(dev);
>   
> -    s->bh0 = qemu_bh_new(timer0_hit, s);
> -    s->bh1 = qemu_bh_new(timer1_hit, s);
> -    s->ptimer0 = ptimer_init_with_bh(s->bh0, PTIMER_POLICY_DEFAULT);
> -    s->ptimer1 = ptimer_init_with_bh(s->bh1, PTIMER_POLICY_DEFAULT);
> +    s->ptimer0 = ptimer_init(timer0_hit, s, PTIMER_POLICY_DEFAULT);
> +    s->ptimer1 = ptimer_init(timer1_hit, s, PTIMER_POLICY_DEFAULT);
>   
> +    ptimer_transaction_begin(s->ptimer0);
>       ptimer_set_freq(s->ptimer0, s->freq_hz);
> +    ptimer_transaction_commit(s->ptimer0);
> +    ptimer_transaction_begin(s->ptimer1);
>       ptimer_set_freq(s->ptimer1, s->freq_hz);
> +    ptimer_transaction_commit(s->ptimer1);
>   }
>   
>   static const VMStateDescription vmstate_milkymist_sysctl = {