From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paul Mundt Date: Mon, 01 Jun 2009 10:57:48 +0000 Subject: Re: [PATCH] clocksource: SuperH TMU Timer driver Message-Id: <20090601105747.GA32746@linux-sh.org> List-Id: References: <20090501065100.8800.99808.sendpatchset@rx1.opensource.se> In-Reply-To: <20090501065100.8800.99808.sendpatchset@rx1.opensource.se> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-sh@vger.kernel.org On Mon, Jun 01, 2009 at 07:50:40PM +0900, Magnus Damm wrote: > 2009/5/30 Shin-ichiro KAWASAKI : > > I made some investigation, and found that the warnings are printed > > after zero value is set to TCOR. ?I checked SH7785 hardware manual, > > but could not find any description what happens when zero value set > > to TCOR. > > Thanks for investigating. I read a few SH manuals before converting > the old driver, but I couldn't find any description of zero value. > Same as you. > > The idea with zero value TCOR comes from the old driver. It may be > there for some historical reason, or it may just be plain wrong. I've > sometimes seen interrupt bursts with the old tmu driver which may be > related. > It was mostly there just because it worked and seemed like a reasonable thing to do, and because no one had any better ideas on what to do in that situation. But yes, technically the behaviour is undefined, and so finding something slightly more precise is a good idea.