linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Etienne Carriere <etienne.carriere@linaro.org>
To: Sudeep Holla <sudeep.holla@arm.com>
Cc: linux-kernel@vger.kernel.org,
	"moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE" 
	<linux-arm-kernel@lists.infradead.org>,
	Cristian Marussi <cristian.marussi@arm.com>,
	Vincent Guittot <vincent.guittot@linaro.org>,
	Souvik Chakravarty <Souvik.Chakravarty@arm.com>,
	Peng Fan <peng.fan@nxp.com>
Subject: Re: [PATCH 4/5] firmware: arm_scmi: smc transport supports multi-message pool
Date: Fri, 9 Oct 2020 14:43:31 +0200	[thread overview]
Message-ID: <CAN5uoS8tz0wXkD1dtFbAYBWHvngHG8KeUD2JkK32siPa2MwgYA@mail.gmail.com> (raw)
In-Reply-To: <20201008211116.l6gbym2ypb6lzlo7@bogus>

On Thu, 8 Oct 2020 at 23:11, Sudeep Holla <sudeep.holla@arm.com> wrote:
>
> On Thu, Oct 08, 2020 at 04:37:21PM +0200, Etienne Carriere wrote:
> > There is no reason for the smc transport to restrict itself to a 1
> > message pool. More can be allocated, messages are copied from/to the
> > shared memory only on SMC exit/entry hence SCMI driver can play with
> > several messages.
> >
> > Use value of 20 to mimic mailbox transport implementation.
>
> What is the need to mimic ?

I had to pick a value. I can't say whether 2, 5 or 20 is better.
I looks how the mailbox transport did and used the same value
as it seemed reasonable regarding its memory cost.

>
> > Any high value could fit. This should be something configurable.
>
> Why not 10 or 100 ? I see any value other than 1 is useless as we lock
> the channel in send_message and we don't maintain a queue like mailbox.

I'll check again.
Playing with SCMI voltage domain [1], it happens that I needed several
preallocated
message buffers unless what regulators fail to be probed.

[1] https://lkml.org/lkml/2020/10/5/1341

Regards,
etienne

>
> --
> Regards,
> Sudeep

  reply	other threads:[~2020-10-09 12:43 UTC|newest]

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-08 14:37 [PATCH 1/5] firmware: arm_scmi: always initialize protocols Etienne Carriere
2020-10-08 14:37 ` [PATCH 2/5] firmware: arm_scmi: fix transfer missing re-initialization Etienne Carriere
2020-10-08 21:18   ` Sudeep Holla
2020-10-09 12:38     ` Etienne Carriere
2020-10-09 15:20       ` Sudeep Holla
2020-10-12 14:17   ` [PATCH] firmware: arm_scmi: Add missing Rx size re-initialisation Sudeep Holla
2020-10-13  9:58     ` Etienne Carriere
2020-10-13 10:16       ` Sudeep Holla
2020-10-13 10:50     ` Sudeep Holla
2020-10-08 14:37 ` [PATCH 3/5] firmware: arm_scmi: add config dependency for smc transport Etienne Carriere
2020-10-08 21:08   ` Sudeep Holla
2020-10-09 12:33     ` Etienne Carriere
2020-10-09 15:58       ` Sudeep Holla
2020-10-12 10:11         ` Etienne Carriere
2020-10-08 14:37 ` [PATCH 4/5] firmware: arm_scmi: smc transport supports multi-message pool Etienne Carriere
2020-10-08 21:11   ` Sudeep Holla
2020-10-09 12:43     ` Etienne Carriere [this message]
2020-10-09 15:17       ` Sudeep Holla
2020-10-12  8:57         ` Sudeep Holla
2020-10-12  9:12           ` Etienne Carriere
2020-10-08 14:37 ` [PATCH 5/5] firmware: arm_scmi: fix ARCH_COLD_RESET Etienne Carriere
2020-10-08 21:16   ` Sudeep Holla
2020-10-08 19:17 ` [PATCH 1/5] firmware: arm_scmi: always initialize protocols Sudeep Holla
2020-10-09 12:31   ` Etienne Carriere
2020-10-09 16:31     ` Cristian Marussi
2020-10-12  9:32     ` Sudeep Holla
2020-10-13 10:45 ` Sudeep Holla

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=CAN5uoS8tz0wXkD1dtFbAYBWHvngHG8KeUD2JkK32siPa2MwgYA@mail.gmail.com \
    --to=etienne.carriere@linaro.org \
    --cc=Souvik.Chakravarty@arm.com \
    --cc=cristian.marussi@arm.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=peng.fan@nxp.com \
    --cc=sudeep.holla@arm.com \
    --cc=vincent.guittot@linaro.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).