On 15:12 Wed 23 Nov , Marc Vertes wrote: > Dmitry Artamonow <mad_soft@xxxxxxxx> wrote: > > > "via_wdt" seems to be a too generic name. What if someone will want to > > write driver for some incompatible watchdog also made by VIA? > > Maybe it's worth to use something more specific - say, "via_vx8xx_wdt"? > > > According to Harald, it is the same watchdog on all via chipsets and > back to Athlon chipsets. But why not. In that case I think it's ok to leave via_wdt as is. > > Why is to rely on BIOS setup? Is there really no information on what > > registers to write to start watchdog? Or you was just lazy to find it? > > It took me less than a minute to google up a datasheet[1] on VX800/VX820 > > and it seems to have all needed information to implement proper start() > > and stop() functions. I suppose info on watchdog registers should be > > applicable to VX855 as well - but it's better to check on your hardware > > anyway. > > > > [1] http://linux.via.com.tw/support/beginDownload.action?eleid=161&fid=241 > > > I rely on BIOS setup because it is the only working method on the > hardware I could test on. This watchdog stuff exists on VIA cpus for > years (back to Athlon chipsets) and still no working open > source driver. Wonder why? > > Of course I read the datasheet of the VX855 southbridge prior to > write this driver. And the VX800 one, the CX700 one. Unfortunately, > the instructions to start, stop, get and set counters simply > do not work. The doc is false and/or incomplete. Harald > already implemented a full version of this driver back in 2009 > (http://git.gnumonks.org/cgi-bin/gitweb.cgi?p=linux-2.6-via.git;a=shortlog; h=refs/heads/via-wdt), > but not working. Questions to VIA remain unanswered. > > So I decided to keep in the source code only what really works, and not > the well documented but non functional stuff. If you can test or find > hardware where those instructions work as advertised, I will be happy > to expose them again in an updated driver. > > The current result, in addition of actually working, is safe, > simple, and compatible with potential "correct" configurations. Ok. Thanks to you and Harald for explaining! That's sad HW doesn't behave according to datasheets. Maybe it's worth to add a note about this in the driver to warn future hackers? :) -- Best regards, Dmitry "MAD" Artamonow -- To unsubscribe from this list: send the line "unsubscribe linux-watchdog" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
