[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <ade36b07c4f60a755a3b7700250e56ec61711d53.camel@mediatek.com>
Date: Mon, 4 Mar 2024 02:11:18 +0000
From: CK Hu (胡俊光) <ck.hu@...iatek.com>
To: "jassisinghbrar@...il.com" <jassisinghbrar@...il.com>,
"matthias.bgg@...il.com" <matthias.bgg@...il.com>,
Jason-JH Lin (林睿祥) <Jason-JH.Lin@...iatek.com>,
"chunkuang.hu@...nel.org" <chunkuang.hu@...nel.org>
CC: "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
Singo Chang (張興國) <Singo.Chang@...iatek.com>,
"linux-mediatek@...ts.infradead.org" <linux-mediatek@...ts.infradead.org>,
Jason-ch Chen (陳建豪)
<Jason-ch.Chen@...iatek.com>, Shawn Sung (宋孝謙)
<Shawn.Sung@...iatek.com>, Nancy Lin (林欣螢)
<Nancy.Lin@...iatek.com>, Project_Global_Chrome_Upstream_Group
<Project_Global_Chrome_Upstream_Group@...iatek.com>,
"linux-arm-kernel@...ts.infradead.org"
<linux-arm-kernel@...ts.infradead.org>,
"angelogioacchino.delregno@...labora.com"
<angelogioacchino.delregno@...labora.com>
Subject: Re: [RESEND, PATCH 4/5] soc: mediatek: mtk-cmdq: Add
cmdq_pkt_acquire_event() function
Hi, Jason:
On Fri, 2024-03-01 at 22:44 +0800, Jason-JH.Lin wrote:
> Add cmdq_pkt_acquire_event() function to support CMDQ user making
> an instruction for acquiring event.
>
> CMDQ users can use cmdq_pkt_acquire_event() and
> cmdq_pkt_clear_event()
> to acquire GCE event and release GCE event and achieve the MUTEX_LOCK
> protection between GCE threads.
I'm not clear what acquire do in detail. This is what I guess:
cmdq_pkt_acquire_event() would wait for event to be cleared. After
event is cleared, cmdq_pkt_acquire_event() would set event and keep
executing next command. So the mutex would work like this
cmdq_pkt_acquire_event() /* mutex lock */
/* critical secton */
cmdq_pkt_clear_event() /* mutex unlock */
If it's so, describe as detail as this. If not, describe how it do.
As I know, GCE is single core, so multiple thread is served by single
GCE, why need mutex lock?
Regards,
CK
>
> Signed-off-by: Jason-JH.Lin <jason-jh.lin@...iatek.com>
> ---
> drivers/soc/mediatek/mtk-cmdq-helper.c | 15 +++++++++++++++
> include/linux/soc/mediatek/mtk-cmdq.h | 9 +++++++++
> 2 files changed, 24 insertions(+)
>
> diff --git a/drivers/soc/mediatek/mtk-cmdq-helper.c
> b/drivers/soc/mediatek/mtk-cmdq-helper.c
> index 2e9fc9bb1183..0183b40a0eff 100644
> --- a/drivers/soc/mediatek/mtk-cmdq-helper.c
> +++ b/drivers/soc/mediatek/mtk-cmdq-helper.c
> @@ -342,6 +342,21 @@ int cmdq_pkt_wfe(struct cmdq_pkt *pkt, u16
> event, bool clear)
> }
> EXPORT_SYMBOL(cmdq_pkt_wfe);
>
> +int cmdq_pkt_acquire_event(struct cmdq_pkt *pkt, u16 event)
> +{
> + struct cmdq_instruction inst = {};
> +
> + if (event >= CMDQ_MAX_EVENT)
> + return -EINVAL;
> +
> + inst.op = CMDQ_CODE_WFE;
> + inst.value = CMDQ_WFE_UPDATE | CMDQ_WFE_UPDATE_VALUE |
> CMDQ_WFE_WAIT;
> + inst.event = event;
> +
> + return cmdq_pkt_append_command(pkt, inst);
> +}
> +EXPORT_SYMBOL(cmdq_pkt_acquire_event);
> +
> 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 2fe9be240fbc..de93c0a8e8a9 100644
> --- a/include/linux/soc/mediatek/mtk-cmdq.h
> +++ b/include/linux/soc/mediatek/mtk-cmdq.h
> @@ -202,6 +202,15 @@ int cmdq_pkt_mem_move(struct cmdq_pkt *pkt,
> dma_addr_t src_addr, dma_addr_t dst_
> */
> int cmdq_pkt_wfe(struct cmdq_pkt *pkt, u16 event, bool clear);
>
> +/**
> + * cmdq_pkt_acquire_event() - append acquire event command to the
> CMDQ packet
> + * @pkt: the CMDQ packet
> + * @event: the desired event to be acquired
> + *
> + * Return: 0 for success; else the error code is returned
> + */
> +int cmdq_pkt_acquire_event(struct cmdq_pkt *pkt, u16 event);
> +
> /**
> * cmdq_pkt_clear_event() - append clear event command to the CMDQ
> packet
> * @pkt: the CMDQ packet
Powered by blists - more mailing lists