From: Andy Green <andy@warmcat.com>
To: Stanislav Brabec <utx@penguin.cz>
Cc: Eric Miao <eric.y.miao@gmail.com>,
dbaryshkov@gmail.com, Cyril Hrubis <metan@ucw.cz>,
arminlitzel@web.de, kernel list <linux-kernel@vger.kernel.org>,
Dirk@opfer-online.de, lenz@cs.wisc.edu, rpurdie@rpsys.net,
linux-arm-kernel <linux-arm-kernel@lists.infradead.org>,
Pavel Machek <pavel@ucw.cz>,
thommycheck@gmail.com, zaurus-devel@www.linuxtogo.org,
omegamoon@gmail.com
Subject: Re: bit errors on spitz
Date: Fri, 12 Mar 2010 11:13:39 +0000 [thread overview]
Message-ID: <4B9A21E3.4020607@warmcat.com> (raw)
In-Reply-To: <1268390588.4963.66.camel@utx.utx.cz>
On 03/12/10 10:43, Somebody in the thread at some point said:
> Andy Green wrote:
>
>> In that case is the PXA CF driver PIO? Then it can be the same load on
>> Vcore issue in disguise.
>
> There is a proprietary ASIC chip (Sharp Scoop) that handles CF and HDD
> access (and also several additional GPIOs):
> http://www.penguin.cz/~utx/zaurus/datasheets/ASIC_S1L50752B26B200/412752.PDF
Right but not thinking about its power arrangements, rather the load on
the CPU itself when it's transferring data to / from CF interface (via
this ASIC).
If the ASIC has bus master DMA and that's used by the driver then fair
enough, otherwise if it is done by PIO in the driver "while using CF"
(as mentioned in most symptoms) becomes the same as saying "during 100%
load on CPU" which is what leads to dents in Vcore and potential
instability by that same Vcore path.
-Andy
next prev parent reply other threads:[~2010-03-12 11:13 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-03-05 21:27 bit errors on spitz Pavel Machek
2010-03-08 5:37 ` Eric Miao
2010-03-08 7:28 ` Pavel Machek
2010-03-08 8:25 ` Cyril Hrubis
2010-03-08 11:48 ` Stanislav Brabec
2010-03-08 12:16 ` Cyril Hrubis
2010-03-08 12:42 ` Russell King - ARM Linux
2010-03-08 13:32 ` Cyril Hrubis
2010-06-03 0:01 ` [URGENT] Re: bit errors on spitz + voipac Marek Vasut
2010-06-03 2:30 ` Eric Miao
2010-03-21 20:40 ` bit errors on spitz Pavel Machek
2010-03-11 13:25 ` Andy Green
2010-03-11 15:42 ` Stanislav Brabec
2010-03-11 21:21 ` Andy Green
2010-03-12 9:07 ` Stanislav Brabec
2010-03-12 9:33 ` Andy Green
2010-03-12 10:43 ` Stanislav Brabec
2010-03-12 11:13 ` Andy Green [this message]
2010-03-21 20:43 ` Pavel Machek
2010-03-21 21:42 ` Stanislav Brabec
2010-03-29 18:27 ` Pavel Machek
2010-03-29 18:52 ` Stanislav Brabec
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=4B9A21E3.4020607@warmcat.com \
--to=andy@warmcat.com \
--cc=Dirk@opfer-online.de \
--cc=arminlitzel@web.de \
--cc=dbaryshkov@gmail.com \
--cc=eric.y.miao@gmail.com \
--cc=lenz@cs.wisc.edu \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=metan@ucw.cz \
--cc=omegamoon@gmail.com \
--cc=pavel@ucw.cz \
--cc=rpurdie@rpsys.net \
--cc=thommycheck@gmail.com \
--cc=utx@penguin.cz \
--cc=zaurus-devel@www.linuxtogo.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