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.4.64.0902061353280.7686@axis700.grange you wrote:
In message Pine.LNX.4.64.0902061002160.4970@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.
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