From: sylvain.rochet@finsecur.com (Sylvain Rochet)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH v2 02/12] pm: at91: Workaround DDRSDRC self-refresh bug with LPDDR1 memories.
Date: Mon, 26 Jan 2015 11:36:05 +0100 [thread overview]
Message-ID: <20150126103605.GA20837@gradator.net> (raw)
In-Reply-To: <1422265139-23011-1-git-send-email-wenyou.yang@atmel.com>
Hello Wenyou,
On Mon, Jan 26, 2015 at 05:38:59PM +0800, Wenyou Yang wrote:
> From: Peter Rosin <peda@axentia.se>
>
> The DDRSDR controller fails miserably to put LPDDR1 memories in
> self-refresh. Force the controller to think it has DDR2 memories
> during the self-refresh period, as the DDR2 self-refresh spec is
> equivalent to LPDDR1, and is correctly implemented in the
> controller.
>
> Assume that the second controller has the same fault, but that is
> untested.
>
> Signed-off-by: Peter Rosin <peda@axentia.se>
> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
> ---
> arch/arm/mach-at91/pm_slowclock.S | 43 +++++++++++++++++++++++++++++++-----
> include/soc/at91/at91sam9_ddrsdr.h | 2 +-
> 2 files changed, 39 insertions(+), 6 deletions(-)
>
> diff --git a/arch/arm/mach-at91/pm_slowclock.S b/arch/arm/mach-at91/pm_slowclock.S
> index e2bfaf5..1155217 100644
> --- a/arch/arm/mach-at91/pm_slowclock.S
> +++ b/arch/arm/mach-at91/pm_slowclock.S
> @@ -100,6 +100,16 @@ ddr_sr_enable:
> cmp memctrl, #AT91_MEMCTRL_DDRSDR
> bne sdr_sr_enable
>
> + /* LPDDR1 --> force DDR2 mode during self-refresh */
I think we should explain we are dealing with an errata here, this is
not obvious at first sight, the patch summary may find its place here :-)
Sylvain
WARNING: multiple messages have this Message-ID (diff)
From: Sylvain Rochet <sylvain.rochet@finsecur.com>
To: Wenyou Yang <wenyou.yang@atmel.com>
Cc: nicolas.ferre@atmel.com, linux@arm.linux.org.uk,
linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org,
alexandre.belloni@free-electrons.com, peda@axentia.se
Subject: Re: [PATCH v2 02/12] pm: at91: Workaround DDRSDRC self-refresh bug with LPDDR1 memories.
Date: Mon, 26 Jan 2015 11:36:05 +0100 [thread overview]
Message-ID: <20150126103605.GA20837@gradator.net> (raw)
In-Reply-To: <1422265139-23011-1-git-send-email-wenyou.yang@atmel.com>
Hello Wenyou,
On Mon, Jan 26, 2015 at 05:38:59PM +0800, Wenyou Yang wrote:
> From: Peter Rosin <peda@axentia.se>
>
> The DDRSDR controller fails miserably to put LPDDR1 memories in
> self-refresh. Force the controller to think it has DDR2 memories
> during the self-refresh period, as the DDR2 self-refresh spec is
> equivalent to LPDDR1, and is correctly implemented in the
> controller.
>
> Assume that the second controller has the same fault, but that is
> untested.
>
> Signed-off-by: Peter Rosin <peda@axentia.se>
> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
> ---
> arch/arm/mach-at91/pm_slowclock.S | 43 +++++++++++++++++++++++++++++++-----
> include/soc/at91/at91sam9_ddrsdr.h | 2 +-
> 2 files changed, 39 insertions(+), 6 deletions(-)
>
> diff --git a/arch/arm/mach-at91/pm_slowclock.S b/arch/arm/mach-at91/pm_slowclock.S
> index e2bfaf5..1155217 100644
> --- a/arch/arm/mach-at91/pm_slowclock.S
> +++ b/arch/arm/mach-at91/pm_slowclock.S
> @@ -100,6 +100,16 @@ ddr_sr_enable:
> cmp memctrl, #AT91_MEMCTRL_DDRSDR
> bne sdr_sr_enable
>
> + /* LPDDR1 --> force DDR2 mode during self-refresh */
I think we should explain we are dealing with an errata here, this is
not obvious at first sight, the patch summary may find its place here :-)
Sylvain
next prev parent reply other threads:[~2015-01-26 10:36 UTC|newest]
Thread overview: 56+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-01-26 9:36 [PATCH v2 00/12] AT91 pm cleanup for 3.20 Wenyou Yang
2015-01-26 9:36 ` Wenyou Yang
2015-01-26 9:37 ` [PATCH v2 01/12] pm: at91: pm_slowclock: improve reliability of suspend/resume Wenyou Yang
2015-01-26 9:37 ` Wenyou Yang
2015-01-26 14:54 ` [PATCH v2 0/2] " Sylvain Rochet
2015-01-26 14:54 ` Sylvain Rochet
2015-01-26 14:54 ` [PATCH v2 1/2] pm: at91: pm_slowclock: fix suspend/resume hang up in timeouts Sylvain Rochet
2015-01-26 14:54 ` Sylvain Rochet
2015-01-26 14:54 ` [PATCH v2 2/2] pm: at91: pm_slowclock: remove clocks which are already stopped when entering slow clock mode Sylvain Rochet
2015-01-26 14:54 ` Sylvain Rochet
2015-01-26 9:38 ` [PATCH v2 02/12] pm: at91: Workaround DDRSDRC self-refresh bug with LPDDR1 memories Wenyou Yang
2015-01-26 9:38 ` Wenyou Yang
2015-01-26 10:36 ` Sylvain Rochet [this message]
2015-01-26 10:36 ` Sylvain Rochet
2015-01-26 13:34 ` Nicolas Ferre
2015-01-26 13:34 ` Nicolas Ferre
2015-01-26 13:44 ` Sylvain Rochet
2015-01-26 13:44 ` Sylvain Rochet
2015-01-26 15:58 ` Peter Rosin
2015-01-26 15:58 ` Peter Rosin
2015-01-26 16:04 ` Nicolas Ferre
2015-01-26 16:04 ` Nicolas Ferre
2015-01-26 16:11 ` Sylvain Rochet
2015-01-26 16:11 ` Sylvain Rochet
2015-01-26 9:39 ` [PATCH v2 03/12] pm: at91: pm_slowclock: remove the unused code related with SLOWDOWN_MASTER_CLOCK Wenyou Yang
2015-01-26 9:39 ` Wenyou Yang
2015-01-26 9:40 ` [PATCH v2 04/12] pm: at91: move the copying the sram function to the sram initializationi phase Wenyou Yang
2015-01-26 9:40 ` Wenyou Yang
2015-01-26 12:57 ` Sergei Shtylyov
2015-01-26 12:57 ` Sergei Shtylyov
2015-01-27 3:27 ` Yang, Wenyou
2015-01-27 3:27 ` Yang, Wenyou
2015-01-26 9:40 ` [PATCH v2 05/12] ARM: at91: move select SRAM to ARCH_AT91 Wenyou Yang
2015-01-26 9:40 ` Wenyou Yang
2015-01-26 9:41 ` [PATCH v2 06/12] pm: at91: remove the config item CONFIG_AT91_SLOW_CLOCK Wenyou Yang
2015-01-26 9:41 ` Wenyou Yang
2015-01-26 9:42 ` [PATCH v2 07/12] pm: at91: the standby mode uses the same sram function as the suspend to memory mode Wenyou Yang
2015-01-26 9:42 ` Wenyou Yang
2015-01-26 10:09 ` Sylvain Rochet
2015-01-26 10:09 ` Sylvain Rochet
2015-01-27 4:44 ` Yang, Wenyou
2015-01-27 4:44 ` Yang, Wenyou
2015-01-26 9:42 ` [PATCH v2 08/12] pm: at91: rename file name: pm_slowclock.S -->pm_suspend.S Wenyou Yang
2015-01-26 9:42 ` Wenyou Yang
2015-01-26 9:43 ` [PATCH v2 09/12] pm: at91: rename function name: at91_slow_clock()-->at91_pm_suspend_sram_fn Wenyou Yang
2015-01-26 9:43 ` Wenyou Yang
2015-01-26 9:44 ` [PATCH v2 10/12] pm: at91: remove the at91_xxx_standby() function definitions in the pm.h Wenyou Yang
2015-01-26 9:44 ` Wenyou Yang
2015-01-26 9:45 ` [PATCH v2 11/12] pm: at91: setup: remove the struct ramc_ids .data at91_xxx_standby members Wenyou Yang
2015-01-26 9:45 ` Wenyou Yang
2015-01-26 9:45 ` [PATCH v2 12/12] pm: at91: amend the pm_suspend entry for at91_cpuidle_device Wenyou Yang
2015-01-26 9:45 ` Wenyou Yang
2015-01-26 9:55 ` [PATCH v2 00/12] AT91 pm cleanup for 3.20 Sylvain Rochet
2015-01-26 9:55 ` Sylvain Rochet
2015-01-27 2:58 ` Yang, Wenyou
2015-01-27 2:58 ` Yang, Wenyou
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=20150126103605.GA20837@gradator.net \
--to=sylvain.rochet@finsecur.com \
--cc=linux-arm-kernel@lists.infradead.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.