On 10/22, Geert Uytterhoeven wrote: > Hi Mike, > > On Tue, Oct 20, 2015 at 3:07 PM, Geert Uytterhoeven > <geert@xxxxxxxxxxxxxx> wrote: > > On Tue, Oct 20, 2015 at 3:00 PM, Michael Turquette > > <mturquette@xxxxxxxxxxxx> wrote: > >> Quoting Geert Uytterhoeven (2015-10-20 05:31:12) > >>> On Tue, Oct 20, 2015 at 2:24 PM, Michael Turquette > >>> <mturquette@xxxxxxxxxxxx> wrote: > > > >> The bindings should go in for 4.4, but if the driver is slated for 4.5 > >> then can you investigate this some more? Stephen and I are on a mission > >> to have _real_ clk drivers. > > > > Sure, I'll have a deeper look. > > And so I did (on r8a7791/koelsch). > > As I want to have as much clock data/code __init as possible (think > multi-platform kernels --- pinmux data is a disaster here), I have to use > platform_driver_probe(). > > - Calling platform_driver_probe() from core_initcall() or postcore_initcall() > is too early, as the platform device for the CPG hasn't been created yet. > Hence the CPG Clock Domain isn't registered, and all devices fail to probe > as they can't be attached to their Clock Domain. > -> This is where the -ENOENT came from (I incorrectly assumed it came > from the clock code; sorry for that), and it's converted into > -EPROBE_DEFER by genpd_dev_pm_attach(). > > - Calling platform_driver_probe() from arch_initcall() is too late, as the > IRQC is initialized first (it's located before the CPG in .dtsi). > Hence the IRQC can't find it's Clock Domain, and its probe is deferred. > IRQC will be reprobed later, but in the mean time the Ethernet PHY can't > find its IRQ, as the of_mdio code uses irq_of_parse_and_map(), which > plainly ignores EPROBE_DEFER :-( > Nevertheless, Ethernet works... > > - Using subsys_initcall() and later causes even more probe deferral. > > So that's why I went with CLK_OF_DECLARE() again... > Understandable for the few clocks that are used by the interrupt controller, but for the other clocks, could those be registered from a real platform device driver probe path? I've been considering making some API that lets devices associate with the clocks that the file had to register with CLK_OF_DECLARE(). The driver would have to be builtin then (no modules) but otherwise we would be able to benefit from the device driver model for most other clocks. -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project -- 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
