[U-Boot-Users] flat tree clock setting
timur at freescale.com
Fri Nov 10 00:15:38 CET 2006
Scott Wood wrote:
> Are there any boards on which OF_TBCLK is (properly) set to something
> other than what get_tbclk() returns (ignoring the difference in
> rounding)? I don't see any, nor can I think of a reason why such a
> difference should ever exist. Perhaps OF_TBCLK should just be removed?
Ok, I've done some more digging.
On PPC, bd->bi_busfreq is the same as gd->bus_clk. In fact, there are a bunch
of clocks in bd that are equal to similar values in gd. The bd_t contains
info that is passed to non-openfirmware versions of Linux, and the gd_t
contains just general globally-defined data.
My guess is that anything which isn't directly used to boot non-OF Linux
should use the gd structure. So get_tbclk() does the right thing (although
the rounding could be wrong), but OF_TBCLK should probably use gd->bus_clk.
Linux Kernel Developer @ Freescale
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