Messages in this thread | | | Date | Sat, 25 Jan 2014 19:11:07 -0300 | From | Emilio López <> | Subject | Re: [PATCH 0/4] clk: mvebu: fix clk init order |
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Sebastian,
El 25/01/14 18:44, Sebastian Hesselbarth escribió: > On 01/25/2014 10:32 PM, Emilio López wrote: >> El 25/01/14 15:19, Sebastian Hesselbarth escribió: >>> This patch set fixes clk init order that went upside-down with >>> v3.14. I haven't really investigated what caused this, but I assume >>> it is related with DT node reordering by addresses. >> >> The framework should be able to deal with unordered registration. I am >> not very familiar with the mvebu driver though, do you have a valid >> reason to require a specific order? > > Emilio, > > I rather think that everthing registered with CLK_OF_DECLARE cannot > deal with unordered registration. The callback passed to CLK_OF_DECLARE > has to have void as return value, so there is no way to pass errors, > e.g. -EPROBE_DEFER, back to of_clk_init.
Indeed. What I meant is that the framework works fine if you first register a child clock that refers to a not yet registered parent, and then register the parent. The registration need not be strictly ordered.
> The reason for this ordering is that the clock gates depend on core > clocks. It is always that way, so merging both init functions isn't > that odd.
If your only dependency is the parent name, and you can use DT or something else to get it, then you don't need to enforce an order.
>>> Anyway, with v3.14 for MVEBU SoCs, the clock gating driver gets >>> registered before core clocks driver. Unfortunately, we cannot >>> return -EPROBE_DEFER in drivers initialized by clk_of_init. >> >> Why would you need to do so? After a quick inspection on the code, I see >> you may have problems on mvebu_clk_gating_setup() when getting the >> default parent clock name, but I believe you could solve it in an easier >> way by using of_clk_get_parent_name(). > > Ok, I'll look if using of_clk_get_parent_name will help here. But again, > I can see that clk-gating driver gets registered before core-clk driver. > There may be no code to give you the parent name at that time.
After looking at some of the armada*.dtsi, I see you don't list the clock names on the coreclk node, so of_clk_get_parent_name may not be of much value after all.
Cheers,
Emilio -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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