public inbox for linuxppc-dev@ozlabs.org 
 help / color / mirror / Atom feed
From: Olof Johansson <olof@lixom•net>
To: Tirumala Reddy Marri <tmarri@amcc•com>
Cc: linuxppc-dev@ozlabs•org
Subject: Re: Disabling L1 D-cache and side effects
Date: Mon, 29 Sep 2008 13:04:55 -0500	[thread overview]
Message-ID: <20080929180455.GA19014@lixom.net> (raw)
In-Reply-To: <AC5E1C3367E37D44970B81A6ADD1DA2C060530C1@SDCEXCHANGE01.ad.amcc.com>

On Mon, Sep 29, 2008 at 10:05:41AM -0700, Tirumala Reddy Marri wrote:
>  
> Hi,
>   I had to bring up a PPC based SOC with L1 dcache disabled.  I did that
> and tried to boot Linux using RAMDISK/NFS mount. In RAMDISK I see the
> file system errors. In case of NFS mount I see error saying failed to
> load ld.so library.
>  
>  Could you guys please share thoughts what are the different side
> effects might be causing this.

There are a number of things you have to be careful about when you
disable caches. Depending on your implementation, you likely can't use
lwarx/stwcx, cache ops will not work, etc. Also, are you 100% sure that
this is caused only by disabling L1D, and not by any other problems with
your silicon?

If you're doing early bringup of you'll have a whole lot of debug work
in front of you, and this mailing list is probably not the best place
to bring your homework.


-Olof

  reply	other threads:[~2008-09-29 18:00 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <9323BAFB78DE7C4183466AD03F73EA424D46071D@SDCEXCHANGE01.ad.amcc.com>
2008-09-29 17:05 ` Disabling L1 D-cache and side effects Tirumala Reddy Marri
2008-09-29 18:04   ` Olof Johansson [this message]
2008-09-29 21:00     ` Tirumala Reddy Marri
2008-09-29 21:14       ` Olof Johansson
2008-09-29 21:38         ` Tirumala Reddy Marri
2008-09-30  7:16           ` Benjamin Herrenschmidt
2008-09-30 16:57             ` Tirumala Reddy Marri
2008-09-30 21:30               ` Benjamin Herrenschmidt
2008-09-30 22:26                 ` Tirumala Reddy Marri
2008-09-30 22:56                   ` Benjamin Herrenschmidt
2008-10-01 18:07                     ` Tirumala Reddy Marri

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=20080929180455.GA19014@lixom.net \
    --to=olof@lixom$(echo .)net \
    --cc=linuxppc-dev@ozlabs$(echo .)org \
    --cc=tmarri@amcc$(echo .)com \
    /path/to/YOUR_REPLY

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