On Thu, 2007-03-22 at 00:55 -0400, Len Brown wrote: > On Tuesday 20 March 2007 05:21, Zhang Rui wrote: > > From: Zhang Rui <rui.zhang@xxxxxxxxx> > > > > Add ACPI Processor throttling control sysfs interface. > > > > Attribute Mode Description > > state_count RO Maximum throttling state supported by this > > processor. > > active_state RW the current throttling state. > > I like this better than the procfs interface. > In particular, this is simple levels and doesn't get tangled up in percentages. > > However, this gives the user the impression that they can actually > change these values and they will stick -- which may be a lie. > > Firmware sometimes messes with throttling behind our back. > Thermal management can change throttling levels on us > and it isn't clear what happens to the user-request in that context. > Finally, something like the p4-clockmod driver can take over throttling > at the request of the cpufreq sub-system. > > Plus, we have the _TCP enhancements coming from Luming. > Yep. I've discussed with Luming and we only need to add another attribute like "platform_limit". It exports a value "n" which means that only Tn~Tmax throttling states are available currently. > I think we need to sort through these issues before we > can possibly propose the appropriate API for exporting > processor throttling control to user-space. > Agree. Maybe we need a processor throttling state driver just like we do for processor power/performance state control(cpui_dle and cpu_freq). Thanks, Rui - 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
