linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Ulf Hansson <ulf.hansson@linaro.org>
To: Shawn Lin <shawn.lin@rock-chips.com>
Cc: Jaehoon Chung <jh80.chung@samsung.com>,
	Rob Herring <robh+dt@kernel.org>,
	linux-mmc <linux-mmc@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Doug Anderson <dianders@chromium.org>,
	"open list:ARM/Rockchip SoC..."
	<linux-rockchip@lists.infradead.org>,
	"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>
Subject: Re: [RFC PATCH 0/4] Introduce new caps to improve the card's init sequence
Date: Wed, 22 Jun 2016 14:37:39 +0200	[thread overview]
Message-ID: <CAPDyKFp+ugPtHsxa1O9eeArkJjoM2sL2F7gqAekgus1qoi3UUw@mail.gmail.com> (raw)
In-Reply-To: <1465373996-2485-1-git-send-email-shawn.lin@rock-chips.com>

On 8 June 2016 at 10:19, Shawn Lin <shawn.lin@rock-chips.com> wrote:
>
> Hi all,
>
> This patchset is gonna improve the card's init sequence
> by exposing some caps to DT.
>
> The basic idea is to skip sending specific init cmd inspired
> by Carlo Caione's commit[0].
>
> To make it possible, I firstly expose Carlo's MMC_CAP2_NO_SDIO
> to DT and extend two new caps for similar usage of sd and mmc.
> We probably need it because for most of the boards, each of the
> slots should have a specific function when designed. It's impossible
> for one slot which can either to be used as eMMC or a SD card for a
> given board. The same for SDIO case.
>
> We could have two ways to improve it
> A) Skip sending specific commands if knowing we don't support
> the specific card type.
> B) Allow sending specific commands if knowing we do support
> the specific card type.
>
> A) and B) shouldn't have difference, but I take A) as the final
> one as it looks more consistent with Carlo's way, which does not
> seem to break anything as possible.
>
> The only roadblock for this patchset to be landed should be the
> improvement we gain from it. Theoretically sdio-card doesn't get
> improvment as it's already in the first place to be attached.
> But considering the sd and (e)MMC case, we should gain more benifit
> from it.
>
> From the test, we can save nearly 2ms for attaching emmc against the
> original 8ms. And we gain more than 30us improvement for sd card for
> each insert.
>
> [0]: http://permalink.gmane.org/gmane.linux.kernel.mmc/34774
>
>
>
> Shawn Lin (4):
>   Documentation: mmc: add description for new caps
>   mmc: core: expose MMC_CAP2_NO_SDIO to dt-binding
>   mmc: core: add cap-no-sd and cap-no-mmc properties
>   mmc: core: improve initialization flow
>

I would prefer that you restructure this series a bit.

Start by adding each new MMC_CAP2* separately and without involving
the DT parsing.

Make the DT documentation patch come after the above, and add a new
separate patch which exposes the caps to device tree.

In that way, I can pick up the non DT parts and wait for Rob's
ack/nack of the DT bindings.

Kind regards
Uffe

>  Documentation/devicetree/bindings/mmc/mmc.txt |  3 +++
>  drivers/mmc/core/core.c                       | 10 +++++-----
>  drivers/mmc/core/host.c                       |  6 ++++++
>  include/linux/mmc/host.h                      |  2 ++
>  4 files changed, 16 insertions(+), 5 deletions(-)
>
> --
> 2.3.7
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

  parent reply	other threads:[~2016-06-22 12:37 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-06-08  8:19 Shawn Lin
2016-06-08  8:20 ` [RFC PATCH 1/4] Documentation: mmc: add description for new caps Shawn Lin
2016-06-08 20:48   ` Rob Herring
2016-06-22 12:30     ` Ulf Hansson
2016-06-22 15:06   ` Doug Anderson
2016-06-23  1:29     ` Shawn Lin
2016-06-23  4:33       ` Doug Anderson
2016-06-08  8:20 ` [RFC PATCH 2/4] mmc: core: expose MMC_CAP2_NO_SDIO to dt-binding Shawn Lin
2016-06-08  8:20 ` [RFC PATCH 3/4] mmc: core: add cap-no-sd and cap-no-mmc properties Shawn Lin
2016-06-08  8:22 ` [RFC PATCH 4/4] mmc: core: improve initialization flow Shawn Lin
2016-06-22 12:37 ` Ulf Hansson [this message]
2016-06-23  1:35   ` [RFC PATCH 0/4] Introduce new caps to improve the card's init sequence Shawn Lin

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=CAPDyKFp+ugPtHsxa1O9eeArkJjoM2sL2F7gqAekgus1qoi3UUw@mail.gmail.com \
    --to=ulf.hansson@linaro.org \
    --cc=devicetree@vger.kernel.org \
    --cc=dianders@chromium.org \
    --cc=jh80.chung@samsung.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mmc@vger.kernel.org \
    --cc=linux-rockchip@lists.infradead.org \
    --cc=robh+dt@kernel.org \
    --cc=shawn.lin@rock-chips.com \
    --subject='Re: [RFC PATCH 0/4] Introduce new caps to improve the card'\''s init sequence' \
    /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

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).