From 9874647ba1bdf3e1af25e079070a00676f60f2f0 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 8 Jul 2010 00:43:36 +0200 Subject: ACPI / ACPICA: Do not execute _PRW methods during initialization Currently, during initialization ACPICA walks the entire ACPI namespace in search of any device objects with assciated _PRW methods. All of the _PRW methods found are executed in the process to extract the GPE information returned by them, so that the GPEs in question can be marked as "able to wakeup" (more precisely, the ACPI_GPE_CAN_WAKE flag is set for them). The only purpose of this exercise is to avoid enabling the CAN_WAKE GPEs automatically, even if there are _Lxx/_Exx methods associated with them. However, it is both costly and unnecessary, because the host OS has to execute the _PRW methods anyway to check which devices can wake up the system from sleep states. Moreover, it then uses full information returned by _PRW, including the GPE information, so it can take care of disabling the GPEs if necessary. Remove the code that walks the namespace and executes _PRW from ACPICA and modify comments to reflect that change. Make acpi_bus_set_run_wake_flags() disable GPEs for wakeup devices so that they don't cause spurious wakeup events to be signaled. This not only reduces the complexity of the ACPICA initialization code, but in some cases it should reduce the kernel boot time as well. Unfortunately, for this purpose we need a new ACPICA function, acpi_gpe_can_wake(), to be called by the host OS in order to disable the GPEs that can wake up the system and were previously enabled by acpi_ev_initialize_gpe_block() or acpi_ev_update_gpes() (such a GPE should be disabled only once, because the initialization code enables it only once, but it may be pointed to by _PRW for multiple devices and that's why the additional function is necessary). Signed-off-by: Rafael J. Wysocki Signed-off-by: Len Brown --- include/acpi/acpixf.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include/acpi') diff --git a/include/acpi/acpixf.h b/include/acpi/acpixf.h index ba94a889afd1..81d4f3d4b9fd 100644 --- a/include/acpi/acpixf.h +++ b/include/acpi/acpixf.h @@ -63,7 +63,6 @@ extern u32 acpi_dbg_layer; extern u8 acpi_gbl_enable_interpreter_slack; extern u8 acpi_gbl_all_methods_serialized; extern u8 acpi_gbl_create_osi_method; -extern u8 acpi_gbl_leave_wake_gpes_disabled; extern u8 acpi_gbl_use_default_register_widths; extern acpi_name acpi_gbl_trace_method_name; extern u32 acpi_gbl_trace_flags; @@ -286,6 +285,8 @@ acpi_status acpi_enable_gpe(acpi_handle gpe_device, u32 gpe_number); acpi_status acpi_disable_gpe(acpi_handle gpe_device, u32 gpe_number); +acpi_status acpi_gpe_can_wake(acpi_handle gpe_device, u32 gpe_number); + acpi_status acpi_clear_gpe(acpi_handle gpe_device, u32 gpe_number); acpi_status acpi_gpe_wakeup(acpi_handle gpe_device, u32 gpe_number, u8 action); -- cgit v1.2.2