On Mon, 23 Feb 2009, Sascha Hauer wrote: > Hi, > > On Sat, Feb 21, 2009 at 10:32:33PM +0100, Wolfgang Denk wrote: > > Dear Guennadi Liakhovetski, > > > > In message <pine.lnx.4.64.0902061353280.7...@axis700.grange> you wrote: > > > > > > > In message <pine.lnx.4.64.0902061002160.4...@axis700.grange> you wrote: > > > > > Upon power on i.MX31 enables most peripheral clocks, Linux disables > > > > > the ones > > > > > > > > Why does U-Boot do that? > > > > > > i.MX31 does that - the CPU, not U-Boot. I.e., this is the default > > > power-on > > > mode. > > > > Yea, but U-Boot performs h/w initialization. So why does it not - like > > Linux - set sane defaults (with only the necessary clocks enabled) ? > > I simply forgot it. The clock registers do not get resetted on reset, > only on power up.
Well, it depends. On U-Boot reset they do get resetted, but not on Linux reboot. Reason - U-Boot uses the watchdog for reset, Linux just jumps to address 0. I tried using watchdog under Linux for reset - it just hung the system. You might want to investigate it further... Thanks Guennadi --- Guennadi Liakhovetski, Ph.D. DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: +49-8142-66989-0 Fax: +49-8142-66989-80 Email: off...@denx.de _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
