On Wed, Jun 8, 2016 at 9:49 AM, Zheng, Lv <lv.zheng@xxxxxxxxx> wrote: > Hi, > >> From: Rafael J. Wysocki [mailto:rjw@xxxxxxxxxxxxx] >> Subject: Re: [PATCH 1/3] ACPICA: Events: Introduce >> acpi_block_gpe()/acpi_unblock_gpe()/acpi_control_gpe_handling() to >> allow administrative GPE enabling/disabling >> >> On Monday, May 16, 2016 05:11:11 PM Lv Zheng wrote: >> > There is a facility in Linux, developers can manage GPE enabling/disabling >> > through /sys/firmware/acpi/interrupts/gpexx. This is mainly for >> debugging >> > purposes. Many users expect to use this facility to implement quirks to >> > disable specific GPEs when there is a gap in Linux causing GPE flood. >> > This is not working correctly because currently this facility invokes >> > enabling/disabling counting based GPE driver APIs: >> > acpi_enable_gpe()/acpi_disable_gpe() >> > and the GPE drivers can still affect the count to mess up the GPE >> > management purposes. >> > >> > This patch introduces acpi_block_gpe()/acpi_unblock_gpe() to be used in >> such >> > situation instead of acpi_enable_gpe()/acpi_disable_gpe(). >> >> Up to this point, I agree. >> >> > The idea to implement this is to replace the GPE register EN bit with the >> > managed value, block EN set/clear operations but record the operation >> > results in blocked_enabled, so that after the managed state is removed, >> > restore the saved blocked_enabled back to the GPE register EN bit. >> >> Unfortunately, I don't really follow the above paragraph, so chances are >> that >> whoever is not familiar with the code will not be able to follow it either. > [Lv Zheng] > I see. > I should stop talking this using "managed". > It is better to use "masked". > As this facility is actually trying to implement the kind of the facility that can be seen in many other IRQ chips - the IRQ MASK bit. This is a somewhat simplified special case of it, though. >> > Now OSPMs should be able to use this facility to generate quirks. ACPICA >> > BZ 1102. >> > >> > This facility can also be used by the administrator to control the GPE >> > handling mode during the runtime when the driver is capable of handling >> the >> > GPE in both the interrupt mode and the polling mode (for example, the >> Linux >> > EC driver). acpi_control_gpe_handling() is offered for this purpose. Lv >> Zheng. >> >> That is too much. The patch should focus on the block/unblock >> functionality. >> Anything beyond that should be added later IMO. > [Lv Zheng] > OK. > So after examining all of your comments. > I think what I need to improve is eliminating this feature. > That should be able to make the code simpler and thus easier for the others to follow. Sounds good! -- 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
