Re: [PATCH] Comments in the titan ethernet driver for IP header alignment

All of lore.kernel.org
 help / color / mirror / Atom feed

From: Manish Lachwani <mlachwani@mvista.com>
To: Thomas Koeller <thomas.koeller@baslerweb.com>
Cc: Manish Lachwani <mlachwani@prometheus.mvista.com>,
	linux-mips@linux-mips.org, ralf@linux-mips.org
Subject: Re: [PATCH] Comments in the titan ethernet driver for IP header  alignment
Date: Tue, 23 Nov 2004 10:23:11 -0800	[thread overview]
Message-ID: <41A3800F.2010005@mvista.com> (raw)
In-Reply-To: <200411231910.02427.thomas.koeller@baslerweb.com>

Hi Thomas,

Thomas Koeller wrote:
> Hi Manish,
> 
> register 0x103c is not documented in any but the newest version of
> the processor's user manual, and the function documented there has
> _nothing_ to do with header alignment. 

I agree. The document says nothing about IP header alignment. And like I 
said before, this code has been written based on feedback from the chip 
designers. I have no idea why there is not document describing this, as 
yet.

> So either the docs are wrong,
> or the register implements both the documented and undocumented
> functions. In this case, however, the code would be wrong because it
> permanently modifies the register's contents, which could screw up
> packet priority processing.

The code implements sequence of operations that are needed for the chip 
to align IP headers. Thats all. Now, if you think that this can screw up 
packet priority processing in any way, then you should point PMC about 
this potential bug. AFAIK, there are other OS's that use this register 
to fix the IP header alignment issue on the Titan.

Thanks
Manish Lachwani

> 
> Thomas
> 
> On Tuesday 23 November 2004 18:14, Manish Lachwani wrote:
> 
>>Hi Ralf,
>>
>>Attached patch puts comments around the section that programs register
>>0x103C for IP header alignment. Please review ...
>>
>>Thanks
>>Manish Lachwani
> 
>

WARNING: multiple messages have this Message-ID (diff)

From: Manish Lachwani <mlachwani@mvista.com>
To: Thomas Koeller <thomas.koeller@baslerweb.com>
Cc: Manish Lachwani <mlachwani@prometheus.mvista.com>,
	linux-mips@linux-mips.org, ralf@linux-mips.org
Subject: Re: [PATCH] Comments in the titan ethernet driver for IP header alignment
Date: Tue, 23 Nov 2004 10:23:11 -0800	[thread overview]
Message-ID: <41A3800F.2010005@mvista.com> (raw)
Message-ID: <20041123182311.gd0JGSalxNGe3Joy9JvPRP3R9nCNKWubukmsMR8uqgE@z> (raw)
In-Reply-To: <200411231910.02427.thomas.koeller@baslerweb.com>

Hi Thomas,

Thomas Koeller wrote:
> Hi Manish,
> 
> register 0x103c is not documented in any but the newest version of
> the processor's user manual, and the function documented there has
> _nothing_ to do with header alignment. 

I agree. The document says nothing about IP header alignment. And like I 
said before, this code has been written based on feedback from the chip 
designers. I have no idea why there is not document describing this, as 
yet.

> So either the docs are wrong,
> or the register implements both the documented and undocumented
> functions. In this case, however, the code would be wrong because it
> permanently modifies the register's contents, which could screw up
> packet priority processing.

The code implements sequence of operations that are needed for the chip 
to align IP headers. Thats all. Now, if you think that this can screw up 
packet priority processing in any way, then you should point PMC about 
this potential bug. AFAIK, there are other OS's that use this register 
to fix the IP header alignment issue on the Titan.

Thanks
Manish Lachwani

> 
> Thomas
> 
> On Tuesday 23 November 2004 18:14, Manish Lachwani wrote:
> 
>>Hi Ralf,
>>
>>Attached patch puts comments around the section that programs register
>>0x103C for IP header alignment. Please review ...
>>
>>Thanks
>>Manish Lachwani
> 
>

next prev parent reply	other threads:[~2004-11-23 18:23 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-11-23 17:14 [PATCH] Comments in the titan ethernet driver for IP header alignment Manish Lachwani
2004-11-23 18:10 ` Thomas Koeller
2004-11-23 18:23   ` Manish Lachwani [this message]
2004-11-23 18:23     ` Manish Lachwani

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=41A3800F.2010005@mvista.com \
    --to=mlachwani@mvista.com \
    --cc=linux-mips@linux-mips.org \
    --cc=mlachwani@prometheus.mvista.com \
    --cc=ralf@linux-mips.org \
    --cc=thomas.koeller@baslerweb.com \
    /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.