LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Heiko Stuebner <heiko@sntech.de>
To: Enric Balletbo i Serra <enric.balletbo@collabora.com>,
	robh+dt@kernel.org
Cc: myungjoo.ham@samsung.com, kyungmin.park@samsung.com,
	devicetree@vger.kernel.org, linux-pm@vger.kernel.org,
	dbasehore@chromium.org, linux-kernel@vger.kernel.org,
	dianders@google.com, groeck@google.com, kernel@collabora.com,
	Mark Rutland <mark.rutland@arm.com>
Subject: Re: [PATCH 2/6] dt-bindings: clock: add DDR3 standard speed bins.
Date: Fri, 20 Apr 2018 12:58:10 +0200	[thread overview]
Message-ID: <39099779.d2GlTJ02DA@phil> (raw)
In-Reply-To: <62c4b6f0-e67c-8e25-a129-bf0c06c5157b@collabora.com>

Hi Enric,

Am Donnerstag, 19. April 2018, 13:30:16 CEST schrieb Enric Balletbo i Serra:
> On 19/04/18 13:10, Heiko Stuebner wrote:
> > Am Donnerstag, 19. April 2018, 12:40:15 CEST schrieb Enric Balletbo i Serra:
> >> DDR3 SDRAM Standard (JESD79-3F) defines some standard speed bins for
> >> DDR3 memories. The devfreq/rk3399_dmc.txt binding refers to this file
> >> which does not exist, so add a ddr.h file with the standard speed bins
> >> for DDR3.
> >>
> >> Fixes: c1ceb8f7c167 (Documentation: bindings: add dt documentation for rk3399 dmc)
> >> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
> >> ---
> >>
> >>  include/dt-bindings/clock/ddr.h | 34 +++++++++++++++++++++++++++++++++
> >>  1 file changed, 34 insertions(+)
> >>  create mode 100644 include/dt-bindings/clock/ddr.h
> >>
> >> diff --git a/include/dt-bindings/clock/ddr.h b/include/dt-bindings/clock/ddr.h
> >> new file mode 100644
> >> index 000000000000..506aef7e609e
> >> --- /dev/null
> >> +++ b/include/dt-bindings/clock/ddr.h
> >> @@ -0,0 +1,34 @@
> >> +/* SPDX-License-Identifier: (GPL-2.0+ OR MIT) */
> >> +
> >> +#ifndef DT_BINDINGS_DDR_H
> >> +#define DT_BINDINGS_DDR_H
> >> +
> >> +/* DDR3-800 Standard Speed Bins */
> >> +#define DDR3_800D	15
> >> +#define DDR3_800E		18
> >> +/* DDR3-1066 Standard Speed Bins */
> >> +#define DDR3_1066E	18
> >> +#define DDR3_1066F	21
> >> +#define DDR3_1066G	24
> > 
> > looking at the mentioned jedec standard, I don't see where these numerical
> > values are defined in the standard itself. [I may be blind though]
> > 
> 
> Damm it. No, you're not blind. I did an horrible mistake adding an old version
> of this file. It's wrong, that is supposed to be there is DDR3 table available
> in the ATF [1] not this.

Mistakes can always happen ... so no problem :-) .


>         /* 5-5-5 */
> 	DDR3_800D = 0,
> 	/* 6-6-6 */
> 	DDR3_800E = 1,
> 	/* 6-6-6 */
> 	DDR3_1066E = 2,
> 	/* 7-7-7 */
> 	DDR3_1066F = 3,
>         ...
> 
> The value is passed directly to the ATF so the above values are the correct.
> 
> One question that I have on my mind is if this file should be called as is or if
> will be better name as atf-ddr.h or something like that.
> ddr.h -> atf-ddr.h

The more interesting question would be if this isn't a very much rockchip
or even rk3399-specific scheme. So such a generic header name looks very
much out of place (also including the very generic constant names).

So far the only upstream ATF implementation is for the rk3399.


Heiko

> 
> [1]
> https://github.com/ARM-software/arm-trusted-firmware/blob/master/plat/rockchip/rk3399/drivers/dram/dram_spec_timing.h
>
> Sorry about that. Guess it's needed a v2 but let's wait a little bit for if more
> discussion arises.
> 
> Best regards,
>   Enric
> 
> > Could you explain a bit more where these numerical values are coming from?
> > 
> > 
> > Thanks
> > Heiko
> > 
> 
> 

  reply	other threads:[~2018-04-20 10:58 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-04-19 10:40 [PATCH 0/6] devfreq: rk3399_dmc: improve rk3399_dmc driver and it's documentation Enric Balletbo i Serra
2018-04-19 10:40 ` [PATCH 1/6] dt-bindings: devfreq: rk3399_dmc: improve binding documentation Enric Balletbo i Serra
2018-04-19 10:40 ` [PATCH 2/6] dt-bindings: clock: add DDR3 standard speed bins Enric Balletbo i Serra
2018-04-19 11:10   ` Heiko Stuebner
2018-04-19 11:30     ` Enric Balletbo i Serra
2018-04-20 10:58       ` Heiko Stuebner [this message]
2018-04-19 10:40 ` [PATCH 3/6] devfreq: rk3399_dmc: remove wait for dcf irq event Enric Balletbo i Serra
2018-04-24  3:55   ` Chanwoo Choi
2018-04-19 10:40 ` [PATCH 4/6] dt-bindings: devfreq: rk3399_dmc: remove interrupts as is not required Enric Balletbo i Serra
2018-04-24  3:56   ` Chanwoo Choi
2018-04-19 10:40 ` [PATCH 5/6] devfreq: rk3399_dmc: do not print error when get supply and clk defer Enric Balletbo i Serra
2018-04-23 10:44   ` Ulf Hansson
2018-04-23 13:37     ` Ezequiel Garcia
2018-04-24  3:55   ` Chanwoo Choi
2018-04-19 10:40 ` [PATCH 6/6] devfreq: rk3399_dmc: register devfreq notification to dmc driver Enric Balletbo i Serra
2018-04-24  4:08   ` Chanwoo Choi
2018-04-23 10:53 ` [PATCH 0/6] devfreq: rk3399_dmc: improve rk3399_dmc driver and it's documentation Ulf Hansson
     [not found] ` <CGME20180419104054epcas5p49612174afb26493bcd937a0232b9b1df@epcms1p3>
2018-04-24  1:53   ` [PATCH 1/6] dt-bindings: devfreq: rk3399_dmc: improve binding documentation MyungJoo Ham
     [not found] ` <CGME20180419104056epcas2p29c74949b650fea596900e395dec662e8@epcms1p7>
2018-04-24  2:31   ` [PATCH 3/6] devfreq: rk3399_dmc: remove wait for dcf irq event MyungJoo Ham
     [not found] ` <CGME20180419104057epcas5p311ecfdeb6cb535cd7100232d282ac323@epcms1p4>
2018-04-24  2:33   ` [PATCH 5/6] devfreq: rk3399_dmc: do not print error when get supply and clk defer MyungJoo Ham
     [not found] ` <CGME20180419104059epcas2p3fe5aba95859e02307556200a42bc1ac2@epcms1p7>
2018-04-24  4:22   ` [PATCH 6/6] devfreq: rk3399_dmc: register devfreq notification to dmc driver MyungJoo Ham
2018-04-24  8:01     ` Enric Balletbo i Serra

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=39099779.d2GlTJ02DA@phil \
    --to=heiko@sntech.de \
    --cc=dbasehore@chromium.org \
    --cc=devicetree@vger.kernel.org \
    --cc=dianders@google.com \
    --cc=enric.balletbo@collabora.com \
    --cc=groeck@google.com \
    --cc=kernel@collabora.com \
    --cc=kyungmin.park@samsung.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=mark.rutland@arm.com \
    --cc=myungjoo.ham@samsung.com \
    --cc=robh+dt@kernel.org \
    --subject='Re: [PATCH 2/6] dt-bindings: clock: add DDR3 standard speed bins.' \
    /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).