Messages in this thread | | | Date | Mon, 03 Aug 2015 10:55:29 -0700 | From | Stephen Boyd <> | Subject | Re: [PATCH 1/3] clk: versatile: Switch to assigned clock parents |
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On 08/03/2015 07:01 AM, Pawel Moll wrote: > On Sat, 2015-08-01 at 00:44 +0100, Stephen Boyd wrote: >> @@ -179,6 +124,15 @@ static void __init clk_sp810_of_setup(struct device_node *node) >> sp810->timerclken[i].channel = i; >> sp810->timerclken[i].hw.init = &init; >> >> + /* >> + * If DT isn't setting the parent, force it to be >> + * the 1 MHz clock without going through the framework. >> + * We do this before clk_register() so that it can determine >> + * the parent and setup the tree properly. >> + */ >> + if (deprecated) >> + init.ops->set_parent(&sp810->timerclken[i].hw, 1); >> + >> sp810->timerclken[i].clk = clk_register(NULL, >> &sp810->timerclken[i].hw); >> WARN_ON(IS_ERR(sp810->timerclken[i].clk)); > So that's one thing I've got a (small) problem here... > > The above change assumes that SP810 always have 32kHz clock on input 0 > and 1MHz clock on input 1. Yes, this is how it made on VExpress, but it > doesn't have to be the case. The magic picking up the faster clock was > added to handle all possible cases. > > The bottom line is: if all we care is VExpress than it works, but it's > still a hack. Personally I don't like it, however I won't nak the patch > because of this. >
All current dts files in the kernel tree have 1MHz on input 1, so we make this change here to set the parent to input 1 if there isn't an assigned-clock-parents property. Presumably new dts files should have the new property so that things work properly. I tried to find the binding document, but it doesn't look to exist, so I didn't have anything to update.
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