[PATCH 3/3] hw/dma/xilinx_axidma.c: Switch to transaction-based ptimer API

Peter Maydell posted 3 patches 6 years ago
Maintainers: Peter Maydell <peter.maydell@linaro.org>, David Gibson <david@gibson.dropbear.id.au>, Alistair Francis <alistair@alistair23.me>, "Edgar E. Iglesias" <edgar.iglesias@gmail.com>, Jason Wang <jasowang@redhat.com>
[PATCH 3/3] hw/dma/xilinx_axidma.c: Switch to transaction-based ptimer API
Posted by Peter Maydell 6 years ago
Switch the xilinx_axidma 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 <peter.maydell@linaro.org>
---
 hw/dma/xilinx_axidma.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/hw/dma/xilinx_axidma.c b/hw/dma/xilinx_axidma.c
index e035d1f7504..fb3a978e282 100644
--- a/hw/dma/xilinx_axidma.c
+++ b/hw/dma/xilinx_axidma.c
@@ -31,7 +31,6 @@
 #include "hw/ptimer.h"
 #include "hw/qdev-properties.h"
 #include "qemu/log.h"
-#include "qemu/main-loop.h"
 #include "qemu/module.h"
 
 #include "hw/stream.h"
@@ -104,7 +103,6 @@ enum {
 };
 
 struct Stream {
-    QEMUBH *bh;
     ptimer_state *ptimer;
     qemu_irq irq;
 
@@ -242,6 +240,7 @@ static void stream_complete(struct Stream *s)
     unsigned int comp_delay;
 
     /* Start the delayed timer.  */
+    ptimer_transaction_begin(s->ptimer);
     comp_delay = s->regs[R_DMACR] >> 24;
     if (comp_delay) {
         ptimer_stop(s->ptimer);
@@ -255,6 +254,7 @@ static void stream_complete(struct Stream *s)
         s->regs[R_DMASR] |= DMASR_IOC_IRQ;
         stream_reload_complete_cnt(s);
     }
+    ptimer_transaction_commit(s->ptimer);
 }
 
 static void stream_process_mem2s(struct Stream *s, StreamSlave *tx_data_dev,
@@ -551,9 +551,10 @@ static void xilinx_axidma_realize(DeviceState *dev, Error **errp)
         struct Stream *st = &s->streams[i];
 
         st->nr = i;
-        st->bh = qemu_bh_new(timer_hit, st);
-        st->ptimer = ptimer_init_with_bh(st->bh, PTIMER_POLICY_DEFAULT);
+        st->ptimer = ptimer_init(timer_hit, st, PTIMER_POLICY_DEFAULT);
+        ptimer_transaction_begin(st->ptimer);
         ptimer_set_freq(st->ptimer, s->freqhz);
+        ptimer_transaction_commit(st->ptimer);
     }
     return;
 
-- 
2.20.1


Re: [PATCH 3/3] hw/dma/xilinx_axidma.c: Switch to transaction-based ptimer API
Posted by Richard Henderson 6 years ago
On 10/17/19 6:21 AM, Peter Maydell wrote:
> Switch the xilinx_axidma 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 <peter.maydell@linaro.org>
> ---
>  hw/dma/xilinx_axidma.c | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>


r~

Re: [PATCH 3/3] hw/dma/xilinx_axidma.c: Switch to transaction-based ptimer API
Posted by Alistair Francis 6 years ago
On Thu, Oct 17, 2019 at 6:53 AM Peter Maydell <peter.maydell@linaro.org> wrote:
>
> Switch the xilinx_axidma 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 <peter.maydell@linaro.org>

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

Alistair

> ---
>  hw/dma/xilinx_axidma.c | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/hw/dma/xilinx_axidma.c b/hw/dma/xilinx_axidma.c
> index e035d1f7504..fb3a978e282 100644
> --- a/hw/dma/xilinx_axidma.c
> +++ b/hw/dma/xilinx_axidma.c
> @@ -31,7 +31,6 @@
>  #include "hw/ptimer.h"
>  #include "hw/qdev-properties.h"
>  #include "qemu/log.h"
> -#include "qemu/main-loop.h"
>  #include "qemu/module.h"
>
>  #include "hw/stream.h"
> @@ -104,7 +103,6 @@ enum {
>  };
>
>  struct Stream {
> -    QEMUBH *bh;
>      ptimer_state *ptimer;
>      qemu_irq irq;
>
> @@ -242,6 +240,7 @@ static void stream_complete(struct Stream *s)
>      unsigned int comp_delay;
>
>      /* Start the delayed timer.  */
> +    ptimer_transaction_begin(s->ptimer);
>      comp_delay = s->regs[R_DMACR] >> 24;
>      if (comp_delay) {
>          ptimer_stop(s->ptimer);
> @@ -255,6 +254,7 @@ static void stream_complete(struct Stream *s)
>          s->regs[R_DMASR] |= DMASR_IOC_IRQ;
>          stream_reload_complete_cnt(s);
>      }
> +    ptimer_transaction_commit(s->ptimer);
>  }
>
>  static void stream_process_mem2s(struct Stream *s, StreamSlave *tx_data_dev,
> @@ -551,9 +551,10 @@ static void xilinx_axidma_realize(DeviceState *dev, Error **errp)
>          struct Stream *st = &s->streams[i];
>
>          st->nr = i;
> -        st->bh = qemu_bh_new(timer_hit, st);
> -        st->ptimer = ptimer_init_with_bh(st->bh, PTIMER_POLICY_DEFAULT);
> +        st->ptimer = ptimer_init(timer_hit, st, PTIMER_POLICY_DEFAULT);
> +        ptimer_transaction_begin(st->ptimer);
>          ptimer_set_freq(st->ptimer, s->freqhz);
> +        ptimer_transaction_commit(st->ptimer);
>      }
>      return;
>
> --
> 2.20.1
>
>

Re: [PATCH 3/3] hw/dma/xilinx_axidma.c: Switch to transaction-based ptimer API
Posted by Philippe Mathieu-Daudé 6 years ago
Hi Peter,

On 10/17/19 3:21 PM, Peter Maydell wrote:
> Switch the xilinx_axidma 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 <peter.maydell@linaro.org>
> ---
>   hw/dma/xilinx_axidma.c | 9 +++++----
>   1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/hw/dma/xilinx_axidma.c b/hw/dma/xilinx_axidma.c
> index e035d1f7504..fb3a978e282 100644
> --- a/hw/dma/xilinx_axidma.c
> +++ b/hw/dma/xilinx_axidma.c
> @@ -31,7 +31,6 @@
>   #include "hw/ptimer.h"
>   #include "hw/qdev-properties.h"
>   #include "qemu/log.h"
> -#include "qemu/main-loop.h"
>   #include "qemu/module.h"
>   
>   #include "hw/stream.h"
> @@ -104,7 +103,6 @@ enum {
>   };
>   
>   struct Stream {
> -    QEMUBH *bh;
>       ptimer_state *ptimer;
>       qemu_irq irq;
>   
> @@ -242,6 +240,7 @@ static void stream_complete(struct Stream *s)
>       unsigned int comp_delay;
>   
>       /* Start the delayed timer.  */
> +    ptimer_transaction_begin(s->ptimer);
>       comp_delay = s->regs[R_DMACR] >> 24;
>       if (comp_delay) {
>           ptimer_stop(s->ptimer);
> @@ -255,6 +254,7 @@ static void stream_complete(struct Stream *s)
>           s->regs[R_DMASR] |= DMASR_IOC_IRQ;
>           stream_reload_complete_cnt(s);
>       }
> +    ptimer_transaction_commit(s->ptimer);

I'd restrict the transaction here within the if() statement:

-- >8 --
@@ -244,9 +244,11 @@ static void stream_complete(struct Stream *s)
      /* Start the delayed timer.  */
      comp_delay = s->regs[R_DMACR] >> 24;
      if (comp_delay) {
+        ptimer_transaction_begin(s->ptimer);
          ptimer_stop(s->ptimer);
          ptimer_set_count(s->ptimer, comp_delay);
          ptimer_run(s->ptimer, 1);
+        ptimer_transaction_commit(s->ptimer);
      }

      s->complete_cnt--;
---

>   }
>   
>   static void stream_process_mem2s(struct Stream *s, StreamSlave *tx_data_dev,
> @@ -551,9 +551,10 @@ static void xilinx_axidma_realize(DeviceState *dev, Error **errp)
>           struct Stream *st = &s->streams[i];
>   
>           st->nr = i;
> -        st->bh = qemu_bh_new(timer_hit, st);
> -        st->ptimer = ptimer_init_with_bh(st->bh, PTIMER_POLICY_DEFAULT);
> +        st->ptimer = ptimer_init(timer_hit, st, PTIMER_POLICY_DEFAULT);
> +        ptimer_transaction_begin(st->ptimer);
>           ptimer_set_freq(st->ptimer, s->freqhz);
> +        ptimer_transaction_commit(st->ptimer);
>       }
>       return;
>   
> 

Re: [PATCH 3/3] hw/dma/xilinx_axidma.c: Switch to transaction-based ptimer API
Posted by Peter Maydell 6 years ago
On Thu, 17 Oct 2019 at 16:01, Philippe Mathieu-Daudé <philmd@redhat.com> wrote:
>
> Hi Peter,
>
> On 10/17/19 3:21 PM, Peter Maydell wrote:
> > Switch the xilinx_axidma 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 <peter.maydell@linaro.org>
> > ---
> >   hw/dma/xilinx_axidma.c | 9 +++++----
> >   1 file changed, 5 insertions(+), 4 deletions(-)
> >
> > diff --git a/hw/dma/xilinx_axidma.c b/hw/dma/xilinx_axidma.c
> > index e035d1f7504..fb3a978e282 100644
> > --- a/hw/dma/xilinx_axidma.c
> > +++ b/hw/dma/xilinx_axidma.c
> > @@ -31,7 +31,6 @@
> >   #include "hw/ptimer.h"
> >   #include "hw/qdev-properties.h"
> >   #include "qemu/log.h"
> > -#include "qemu/main-loop.h"
> >   #include "qemu/module.h"
> >
> >   #include "hw/stream.h"
> > @@ -104,7 +103,6 @@ enum {
> >   };
> >
> >   struct Stream {
> > -    QEMUBH *bh;
> >       ptimer_state *ptimer;
> >       qemu_irq irq;
> >
> > @@ -242,6 +240,7 @@ static void stream_complete(struct Stream *s)
> >       unsigned int comp_delay;
> >
> >       /* Start the delayed timer.  */
> > +    ptimer_transaction_begin(s->ptimer);
> >       comp_delay = s->regs[R_DMACR] >> 24;
> >       if (comp_delay) {
> >           ptimer_stop(s->ptimer);
> > @@ -255,6 +254,7 @@ static void stream_complete(struct Stream *s)
> >           s->regs[R_DMASR] |= DMASR_IOC_IRQ;
> >           stream_reload_complete_cnt(s);
> >       }
> > +    ptimer_transaction_commit(s->ptimer);
>
> I'd restrict the transaction here within the if() statement:
>
> -- >8 --
> @@ -244,9 +244,11 @@ static void stream_complete(struct Stream *s)
>       /* Start the delayed timer.  */
>       comp_delay = s->regs[R_DMACR] >> 24;
>       if (comp_delay) {
> +        ptimer_transaction_begin(s->ptimer);
>           ptimer_stop(s->ptimer);
>           ptimer_set_count(s->ptimer, comp_delay);
>           ptimer_run(s->ptimer, 1);
> +        ptimer_transaction_commit(s->ptimer);
>       }
>
>       s->complete_cnt--;

The timer_hit callback function itself writes to
s->complete_cnt, so we don't want to allow it to
be called (via the commit()) before stream_complete()
is done with changing that state.

thanks
-- PMM

Re: [PATCH 3/3] hw/dma/xilinx_axidma.c: Switch to transaction-based ptimer API
Posted by Philippe Mathieu-Daudé 6 years ago
On 10/17/19 5:06 PM, Peter Maydell wrote:
> On Thu, 17 Oct 2019 at 16:01, Philippe Mathieu-Daudé <philmd@redhat.com> wrote:
>>
>> Hi Peter,
>>
>> On 10/17/19 3:21 PM, Peter Maydell wrote:
>>> Switch the xilinx_axidma 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 <peter.maydell@linaro.org>
>>> ---
>>>    hw/dma/xilinx_axidma.c | 9 +++++----
>>>    1 file changed, 5 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/hw/dma/xilinx_axidma.c b/hw/dma/xilinx_axidma.c
>>> index e035d1f7504..fb3a978e282 100644
>>> --- a/hw/dma/xilinx_axidma.c
>>> +++ b/hw/dma/xilinx_axidma.c
>>> @@ -31,7 +31,6 @@
>>>    #include "hw/ptimer.h"
>>>    #include "hw/qdev-properties.h"
>>>    #include "qemu/log.h"
>>> -#include "qemu/main-loop.h"
>>>    #include "qemu/module.h"
>>>
>>>    #include "hw/stream.h"
>>> @@ -104,7 +103,6 @@ enum {
>>>    };
>>>
>>>    struct Stream {
>>> -    QEMUBH *bh;
>>>        ptimer_state *ptimer;
>>>        qemu_irq irq;
>>>
>>> @@ -242,6 +240,7 @@ static void stream_complete(struct Stream *s)
>>>        unsigned int comp_delay;
>>>
>>>        /* Start the delayed timer.  */
>>> +    ptimer_transaction_begin(s->ptimer);
>>>        comp_delay = s->regs[R_DMACR] >> 24;
>>>        if (comp_delay) {
>>>            ptimer_stop(s->ptimer);
>>> @@ -255,6 +254,7 @@ static void stream_complete(struct Stream *s)
>>>            s->regs[R_DMASR] |= DMASR_IOC_IRQ;
>>>            stream_reload_complete_cnt(s);
>>>        }
>>> +    ptimer_transaction_commit(s->ptimer);
>>
>> I'd restrict the transaction here within the if() statement:
>>
>> -- >8 --
>> @@ -244,9 +244,11 @@ static void stream_complete(struct Stream *s)
>>        /* Start the delayed timer.  */
>>        comp_delay = s->regs[R_DMACR] >> 24;
>>        if (comp_delay) {
>> +        ptimer_transaction_begin(s->ptimer);
>>            ptimer_stop(s->ptimer);
>>            ptimer_set_count(s->ptimer, comp_delay);
>>            ptimer_run(s->ptimer, 1);
>> +        ptimer_transaction_commit(s->ptimer);
>>        }
>>
>>        s->complete_cnt--;
> 
> The timer_hit callback function itself writes to
> s->complete_cnt, so we don't want to allow it to
> be called (via the commit()) before stream_complete()
> is done with changing that state.

Indeed we have timer_hit() -> stream_reload_complete_cnt() which uses 
s->complete_cnt.

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>