public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Chris Friesen <cfriesen@nortelnetworks.com>
Cc: Linux Kernel list <linux-kernel@vger.kernel.org>,
	Tom Rini <trini@kernel.crashing.org>
Subject: Re: problem with cache flush routine for G5?
Date: Fri, 05 Mar 2004 10:51:08 +1100	[thread overview]
Message-ID: <1078444268.5698.27.camel@gaston> (raw)
In-Reply-To: <40479A50.9090605@nortelnetworks.com>

On Fri, 2004-03-05 at 08:06, Chris Friesen wrote:
> We're running into issues with the "flush_data_cache" routine on the G5.
> 
> For the G5, the L1 dcache is 32K and the L2 cache is 512K. At 128 
> bytes/cacheline, that's 256 and 4096 cachelines, respectively.
> 
> In the existing tree, NUM_CACHE_LINES is set to 128*8, or 1024.  Is this 
> an oversight or am I missing something?
> 
> Also, I'm curious why the dcbf instruction is not used for this.

First of all, why do you need to flush the cache at all ?

If you are talking about the cache flush in the 32 bits bootloaders,
then yes, this seem to be broken, you should ask Tom Rini who
maintain these things.

The kernel proper definitely doesn't contain such a routine.

Ben.



  reply	other threads:[~2004-03-04 23:51 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-03-04 21:06 problem with cache flush routine for G5? Chris Friesen
2004-03-04 23:51 ` Benjamin Herrenschmidt [this message]
2004-03-04 23:57   ` Tom Rini
2004-03-05  0:04     ` Benjamin Herrenschmidt
2004-03-05  0:44       ` Chris Friesen
2004-03-05 15:15       ` Tom Rini
2004-03-05 23:51         ` Benjamin Herrenschmidt
2004-03-05  0:37   ` Chris Friesen
2004-03-05  2:10     ` Benjamin Herrenschmidt
2004-03-05  5:39       ` Chris Friesen
2004-03-05  5:46         ` Benjamin Herrenschmidt
2004-03-05 17:21           ` Chris Friesen
2004-03-05 23:53             ` Benjamin Herrenschmidt
2004-03-06  1:34             ` Segher Boessenkool
2004-03-06  2:31             ` Anton Blanchard

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=1078444268.5698.27.camel@gaston \
    --to=benh@kernel.crashing.org \
    --cc=cfriesen@nortelnetworks.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=trini@kernel.crashing.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