Messages in this thread | | | Date | Thu, 25 Sep 2014 18:35:54 -0700 | From | Stephen Boyd <> | Subject | Re: [PATCH] clk: prevent erronous parsing of children during rate change |
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On 09/23/14 06:38, Tero Kristo wrote: > On 09/22/2014 10:18 PM, Stephen Boyd wrote: >> On 08/21, Tero Kristo wrote: >>> /* Skip children who will be reparented to another clock */ >>> if (child->new_parent && child->new_parent != clk) >>> continue; >> >> Are we not hitting the new_parent check here? I don't understand >> how we can be changing parents here unless the check is being >> avoided, in which case I wonder why determine_rate isn't being >> used. >> > > It depends how the clock underneath handles the situation. The error I > am seeing actually happens with a SoC specific compound clock (DPLL) > which integrates set_rate + mux functionality into a single clock > node. A call to the clk_set_rate changes the parent of this clock > (from bypass clock to reference clock), in addition to changing the > rate (tune the mul+div.) I looked at using the determine rate call > with this type but it breaks everything up... the parent gets changed > but not the clock rate, in addition to some other issues.
Ok. Is this omap3_noncore_dpll_set_rate()? Can we use determine_rate + clk_set_parent_and_rate()? At least clk_set_parent_and_rate() would allow us to do the mult+div and the parent in the same op call, although I don't understand why setting the parent and then setting the rate is not going to work. I'm interested in the other issues that you mentioned too.
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