On Wed, Mar 29, 2017 at 04:24:08PM +0100, Mark Rutland wrote: > On Tue, Mar 28, 2017 at 05:02:20PM +0200, Daniel Lezcano wrote: > > On Wed, Mar 22, 2017 at 12:31:14AM +0800, fu.wei@xxxxxxxxxx wrote: > > > From: Fu Wei <fu.wei@xxxxxxxxxx> > > > > > > When system init with device-tree, we don't know which node will be > > > initialized first. And the code in arch_timer_common_init should wait > > > until per-cpu timer and MMIO timer are both initialized. So we need > > > arch_timer_needs_probing to detect the init status of system. > > > > > > But currently the code is dispersed in arch_timer_needs_probing and > > > arch_timer_common_init. And the function name doesn't specify that > > > it's only for device-tree. This is somewhat confusing. > > > > Can the following patch help you to solve nicely the situation ? > > > > https://www.mail-archive.com/linux-kernel@xxxxxxxxxxxxxxx/msg1360007.html > > This does not help. > > The needs_probing logic is all there to bodge around a problem with > registering sched_clock, when you have two sources of the same > frequency, but one is otherwise better. > > The sysreg clocksource has much lower latency than the MMIO clocksource, > so we always want to use that as the sched_clock if we have it. > Currently, the code ensures this by deferring registration of > sched_clock. > > Ideally, we'd figure that out dynamically, or we'd have a rating > argument. > Ok, I see. Thanks. -- <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook | <http://twitter.com/#!/linaroorg> Twitter | <http://www.linaro.org/linaro-blog/> Blog -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
