[PATCH v2 4/4] soc: mediatek: mtk-cmdq: Add cmdq_pkt_acquire_event() function

[AngeloGioacchino Del Regno]

Il 07/03/24 02:34, Jason-JH.Lin ha scritto:
> Add cmdq_pkt_acquire_event() function to support CMDQ user making
> an instruction for acquiring event.
> 
> CMDQ users can use cmdq_pkt_acquire_event() as `mutex_lock`
> and cmdq_pkt_clear_event() as `mutex_unlock` to protect the global
> resource modified instructions between them.
> 
> cmdq_pkt_acquire_event() would wait for event to be cleared.
> After event is cleared by cmdq_pkt_clear_event() in other GCE threads,
> cmdq_pkt_acquire_event() would set event and keep executing next
> instruction. So the mutex would work like this:
> 
>      cmdq_pkt_acquire_event() /* mutex lock */
> 
>      /* critical secton instructions that modified global resource */
> 
>      cmdq_pkt_clear_event() /* mutex unlock */
> 
> Prevent the critical section instructions from being affected by other
> GCE threads.
> 
> Signed-off-by: Jason-JH.Lin <jason-jh.lin at mediatek.com>

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno at collabora.com>