[PATCH 4/4] ARM: dts: Add minimal support for dm8168-evm

Tony Lindgren tony at atomide.com
Mon Feb 2 09:44:18 PST 2015


* Matthijs van Duin <matthijsvanduin at gmail.com> [150128 13:46]:
> On 26 January 2015 at 16:58, Tony Lindgren <tony at atomide.com> wrote:
> > See earlier I was assuming copy paste issues from dm814x to dm816x
> 
> Ahh, you thought the 816x was 814x-derived... yes I can imagine that
> will have led to some confusion.
> 
> > I'm pretty sure I verified the that the audio_pll_clk1 is hardwwired
> > to 32KiHz by looking at it with a scope on the clkout pin.
> 
> Yeah it comes straight from the "rtcdivider" so it'll produce
> 0.0016384 * devosc.

Not much about "rtcdivider" in the dm816x TRM..
 
> The global clock structure overview in the TRM (figure 2-6) actually
> correctly marks the former-audio-fapll clocks (except audio5 := osc0,
> yielding sysclk22 after divider) but you already need to know what the
> hell is going on to recognize that.

That seems to be in the dm814x TRM. OK so it looks like in
mainline kernel drivers/clk/ti/fapll.c we can then fix the hardcoded
value in ti_fapll_synth_recalc_rate() to return the rate of fd->clk_ref
multiplied 0.0016384 instead of 32768.

And we probably should add what you're explaining to the comments
also to make some sense out of it :)

Regards,

Tony



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