linux-mips
[Top] [All Lists]

Re: [PATCH 26/30] loongson: flush irq write operation

To: Ralf Baechle <ralf@linux-mips.org>
Subject: Re: [PATCH 26/30] loongson: flush irq write operation
From: yanh <yanh@lemote.com>
Date: Wed, 20 May 2009 15:58:04 +0800
Cc: Wu Zhangjin <wuzhangjin@gmail.com>, linux-mips@linux-mips.org, Arnaud Patard <apatard@mandriva.com>, loongson-dev@googlegroups.com, zhangfx@lemote.com, Philippe Vachon <philippe@cowpig.ca>, Zhang Le <r0bertz@gentoo.org>, Erwan Lerale <erwan@thiscow.com>
In-reply-to: <20090520070719.GA24231@linux-mips.org>
Original-recipient: rfc822;linux-mips@linux-mips.org
References: <1242426527.10164.174.camel@falcon> <20090518163603.GA22779@linux-mips.org> <1242700637.4382.21.camel@localhost.localdomain> <20090519160117.GA19672@linux-mips.org> <1242786494.4382.58.camel@localhost.localdomain> <20090520070719.GA24231@linux-mips.org>
Reply-to: yanh@lemote.com
Sender: linux-mips-bounce@linux-mips.org
在 2009-05-20三的 08:07 +0100,Ralf Baechle写道:
> On Wed, May 20, 2009 at 10:28:14AM +0800, yanh wrote:
> 
> > I have test this patch just now. It works well on yeeloong. 
> 
> Thanks for testing.
> 
> > I have one question what's the difference between the two patch? 
> 
> Uncached writes can't be re-ordered.  By adding a read after the last
> write my patch forces not only completion of the preceding write but due
> to this ordering constraint also completion of all preceding writes is
> enforced.
> 
> I/O space writes are slow.  I mean slower than slugs in space.  So my
> patch is an optimization but that was not the point; I really only meant
> to verify that we understood what's going on and we seem to.  Now let's
> fix the real issue and make outX() non-posted.
Thanks for your explanation. 
> 
>   Ralf
> 


<Prev in Thread] Current Thread [Next in Thread>