Re: [PATCH v2 13/14] soc: mediatek: cmdq: add wait no clear event function

Dennis-YC Hsieh
2019-12-12T01:43:06Z

On Wed, 2019-12-11 at 10:04 +0800, CK Hu wrote:
> Hi, Dennis:
>
> On Wed, 2019-11-27 at 09:58 +0800, Dennis YC Hsieh wrote:
> > Add wait no clear event function in cmdq helper functions to wait specific
> > event without clear to 0 after receive it.
> >
> > Signed-off-by: Dennis YC Hsieh <dennis-yc.hsieh@mediatek.com>
> > ---
> > drivers/soc/mediatek/mtk-cmdq-helper.c | 15 +++++++++++++++
> > include/linux/soc/mediatek/mtk-cmdq.h | 10 ++++++++++
> > 2 files changed, 25 insertions(+)
> >
> > diff --git a/drivers/soc/mediatek/mtk-cmdq-helper.c b/drivers/soc/mediatek/mtk-cmdq-helper.c
> > index 10a9b4481e58..6f270fadfb50 100644
> > --- a/drivers/soc/mediatek/mtk-cmdq-helper.c
> > +++ b/drivers/soc/mediatek/mtk-cmdq-helper.c
> > @@ -330,6 +330,21 @@ int cmdq_pkt_wfe(struct cmdq_pkt *pkt, u16 event)
> > }
> > EXPORT_SYMBOL(cmdq_pkt_wfe);
> >
> > +int cmdq_pkt_wait_no_clear(struct cmdq_pkt *pkt, u16 event)
> > +{
> > + struct cmdq_instruction inst = { {0} };
> > +
> > + if (event >= CMDQ_MAX_EVENT)
> > + return -EINVAL;
> > +
> > + inst.op = CMDQ_CODE_WFE;
> > + inst.value = CMDQ_WFE_WAIT | CMDQ_WFE_WAIT_VALUE;
> > + inst.event = event;
> > +
> > + return cmdq_pkt_append_command(pkt, inst);
> > +}
> > +EXPORT_SYMBOL(cmdq_pkt_wait_no_clear);
>
> So the wait command has two version, one is wait and then clear event,
> another is wait and not clear event. The name of cmdq_pkt_wfe() is 'wait
> for event', so it's trivial that we think it does not clear event. I've
> three suggestion for this:
>
> 1. Let cmdq_pkt_wfe() wait and not clear event, and
> cmdq_pkt_wfe_clear_event() wait and clear event.
>
> or
> 2. Let cmdq_pkt_wfe() has a parameter to indicate that clear event or
> not after wait.
>
> or
> 3. Let cmdq_pkt_wfe() wait and not clear event, and not provide wait and
> clear event version. For DRM and MDP, I think both just need wait and
> not clear event.
>
> Regards,
> CK
>

ok, I will change cmdq_pkt_wfe wait and not clear, and expose another
cmdq_pkt_wfe_clear_event() api

Regards,
Dennis

>
> > +
> > int cmdq_pkt_clear_event(struct cmdq_pkt *pkt, u16 event)
> > {
> > struct cmdq_instruction inst = { {0} };
> > diff --git a/include/linux/soc/mediatek/mtk-cmdq.h b/include/linux/soc/mediatek/mtk-cmdq.h
> > index d15d8c941992..40bc61ad8d31 100644
> > --- a/include/linux/soc/mediatek/mtk-cmdq.h
> > +++ b/include/linux/soc/mediatek/mtk-cmdq.h
> > @@ -149,6 +149,16 @@ int cmdq_pkt_write_s_value(struct cmdq_pkt *pkt, dma_addr_t addr,
> > */
> > int cmdq_pkt_wfe(struct cmdq_pkt *pkt, u16 event);
> >
> > +/**
> > + * cmdq_pkt_wait_no_clear() - Append wait for event command to the CMDQ packet,
> > + * without update event to 0 after receive it.
> > + * @pkt: the CMDQ packet
> > + * @event: the desired event type to wait
> > + *
> > + * Return: 0 for success; else the error code is returned
> > + */
> > +int cmdq_pkt_wait_no_clear(struct cmdq_pkt *pkt, u16 event);
> > +
> > /**
> > * cmdq_pkt_clear_event() - append clear event command to the CMDQ packet
> > * @pkt: the CMDQ packet