On Wed, 2016-08-03 at 13:46 +0800, James Liao wrote: > On Mon, 2016-07-11 at 16:24 +0800, James Liao wrote: > > Hi Mike, > > > > On Fri, 2016-07-08 at 16:32 -0700, Michael Turquette wrote: > > > Hi James, > > > > > > Quoting James Liao (2016-07-03 20:51:48) > > > > On Fri, 2016-07-01 at 18:21 -0700, Stephen Boyd wrote: > > > > > (Resending to everyone) > > > > > > > > > > On 06/22, Erin Lo wrote: > > > > > > From: James Liao <jamesjj.liao@xxxxxxxxxxxx> > > > > > > > > > > > > This patch fixed wrong state of parent clocks if they are registered > > > > > > after critical clocks. > > > > > > > > > > > > Signed-off-by: James Liao <jamesjj.liao@xxxxxxxxxxxx> > > > > > > Signed-off-by: Erin Lo <erin.lo@xxxxxxxxxxxx> > > > > > > > > > > It would be nice if you included the information about the > > > > > problem from James' previous mail. This says what it does, but > > > > > doesn't explain what the problem is and how it is fixing it. > > > > > > > > > > > --- > > > > > > drivers/clk/clk.c | 9 ++++++++- > > > > > > 1 file changed, 8 insertions(+), 1 deletion(-) > > > > > > > > > > > > diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c > > > > > > index d584004..e9f5f89 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); > > > > > > + } > > > > > > } > > > > > > > > > > I'm pretty sure I pointed this problem out to Mike when the > > > > > critical clk patches were being pushed. I can't recall what the > > > > > plan was though to fix the problem. I'm pretty sure he said that > > > > > clk_core_reparent() would take care of it, but obviously it is > > > > > not doing that. Or perhaps it was that clk handoff should figure > > > > > out that the parents of a critical clk are also on and thus keep > > > > > them on. > > > > > > > > Hi Mike > > > > > > > > Is there any other patch to fix this issue? Or did I misuse critical > > > > clock flag? > > > > > > There is no fix yes. Your fix is basically correct. I was mistaken back > > > when I told you and Stephen that the framework already took care of > > > this. > > > > > > However, instead of "open coding" this solution, I would rather re-use > > > the __clk_set_parent_{before,after} helpers instead. Can you review/test > > > the following patch and let me know what you think? > > > > > > Thanks, > > > Mike > > > > > > > > > > > > From c0163b3f719b1e219b28ad425f94f9ef54a25a8f Mon Sep 17 00:00:00 2001 > > > From: Michael Turquette <mturquette@xxxxxxxxxxxx> > > > Date: Fri, 8 Jul 2016 16:05:22 -0700 > > > Subject: [PATCH] clk: migrate ref counts when orphans are reunited > > > > > > It's always nice to see families reunited, and this is equally true when > > > talking about parent clocks and their children. However, if the orphan > > > clk had a positive prepare_count or enable_count, then we would not > > > migrate those counts up the parent chain correctly. > > > > > > This has manifested with the recent critical clocks feature, which often > > > enables clocks very early, before their parents have been registered. > > > > > > Fixed by replacing the call to clk_core_reparent with calls to > > > __clk_set_parent_{before,after}. > > > > > > Cc: James Liao <jamesjj.liao@xxxxxxxxxxxx> > > > Cc: Erin Lo <erin.lo@xxxxxxxxxxxx> > > > Signed-off-by: Michael Turquette <mturquette@xxxxxxxxxxxx> > > > --- > > > drivers/clk/clk.c | 10 ++++++++-- > > > 1 file changed, 8 insertions(+), 2 deletions(-) > > > > > > diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c > > > index 820a939fb6bb..70efe4c4e0cc 100644 > > > --- a/drivers/clk/clk.c > > > +++ b/drivers/clk/clk.c > > > @@ -2449,8 +2449,14 @@ 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) > > > - clk_core_reparent(orphan, parent); > > > > Is it correct to remove clk_core_reparent()? It lacks > > __clk_recalc_accuracies() and __clk_recalc_rates(), so the new parent's > > rate will not propagate correctly. > > > > For example, I set vdec_sel as a critical clock. Without your patch, the > > result was: > > > > vdecpll 0 0 338000000 > > vdecpll_ck 1 1 338000000 > > vdec_sel 1 1 338000000 > > > > With your patch, it became: > > > > vdecpll 1 1 338000000 > > vdecpll_ck 1 1 0 > > vdec_sel 1 1 0 > > > > The prepare_count and enable_count are correct with your patch, but the > > rates of vdecpll_ck and vdec_sel become incorrect. > > > > > > > + /* > > > + * we could call __clk_set_parent, but that would result in a > > > + * reducant call to the .set_rate op, if it exists > > > + */ > > > + if (parent) { > > > + __clk_set_parent_before(orphan, parent); > > > + __clk_set_parent_after(orphan, parent, NULL); > > > + } > > > } > > > > > > /* > > > > Hi Mike, > > Do you have new patches to fix new clock parents? If not, I think we can > use my patch first. Is it okay? > Hi Stephen, Do you have comments for the bug fixing? I prefer to use my patch (clk: fix initial state of critical clock's parents). How do you think? 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