Hi Stephen, Mike, Lee, On Mon, 2016-05-09 at 15:13 -0700, Stephen Boyd wrote: > On 05/09, James Liao wrote: > > Hi Stephen, > > > > On Fri, 2016-05-06 at 16:12 -0700, Stephen Boyd wrote: > > > On 04/14, James Liao wrote: > > > > Some system clocks should be turned on by default on MT2701. > > > > This patch enable these clocks when related clocks have > > > > been registered. > > > > > > > > Signed-off-by: James Liao <jamesjj.liao@xxxxxxxxxxxx> > > > > --- > > > > > > critical clks got merged now (sorry I'm slowly getting back to > > > looking at patches). Please use that flag. > > > > I don't see critical clock support in v4.6-rc7. Is there a repo/branch > > that has critical clocks merged? > > > > Right, it's in clk-next in the clk tree. I got the latest code from clk-next and tried to use CLK_IS_CRITICAL fro critical clocks. But There is something wrong with CLK_IS_CRITICAL. For example, if we set vdec_sel as a critical clock, we'll get the following result: vdecpll 0 0 vdecpll_ck 1 1 vdec_sel 1 1 vdec_sel and vdecpll_ck are TOPCKGEN clocks. vdecpll is a APMIXEDSYS PLL, which will be registered after TOPCKGEN clocks. The prepare and enable count are incorrect in this case. We may need to prepare/enable a parent clock if an enabled orphan clock re-parent to it. I tried the following modification and it can resolve this issue. But I'm not sure it's a correct place to enable parent clcoks. May I have your comment on this? ------------------------------------------------------------ diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index ce39add..db1bc3a 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -2388,8 +2388,15 @@ static int __clk_core_init(struct clk_core *core) hlist_for_each_entry_safe(orphan, tmp2, &clk_orphan_list, child_node) { struct clk_core *parent = __clk_init_parent(orphan); - if (parent) + if (parent) { clk_core_reparent(orphan, parent); + + if (orphan->prepare_count) + clk_core_prepare(parent); + + if (orphan->enable_count ) + clk_core_enable(parent); + } } /* ------------------------------------------------------------ Best regards, James -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html