From da50337373c90c15c6db6ed4239e87c5a3806f9a Mon Sep 17 00:00:00 2001 From: Lin Ming Date: Mon, 13 Dec 2010 13:39:37 +0800 Subject: ACPICA: Misc comments to minimize code divergence Modify/add some comments to minimize ACPICA/linux GPE code divergence. Acked-by: Rafael J. Wysocki Signed-off-by: Lin Ming Signed-off-by: Len Brown --- drivers/acpi/acpica/evgpeinit.c | 24 ++++++++++++++++++++---- 1 file changed, 20 insertions(+), 4 deletions(-) (limited to 'drivers/acpi/acpica/evgpeinit.c') diff --git a/drivers/acpi/acpica/evgpeinit.c b/drivers/acpi/acpica/evgpeinit.c index 734a494bd705..c59dc2340593 100644 --- a/drivers/acpi/acpica/evgpeinit.c +++ b/drivers/acpi/acpica/evgpeinit.c @@ -45,11 +45,27 @@ #include "accommon.h" #include "acevents.h" #include "acnamesp.h" -#include "acinterp.h" #define _COMPONENT ACPI_EVENTS ACPI_MODULE_NAME("evgpeinit") +/* + * Note: History of _PRW support in ACPICA + * + * Originally (2000 - 2010), the GPE initialization code performed a walk of + * the entire namespace to execute the _PRW methods and detect all GPEs + * capable of waking the system. + * + * As of 10/2010, the _PRW method execution has been removed since it is + * actually unnecessary. The host OS must in fact execute all _PRW methods + * in order to identify the device/power-resource dependencies. We now put + * the onus on the host OS to identify the wake GPEs as part of this process + * and to inform ACPICA of these GPEs via the acpi_setup_gpe_for_wake interface. This + * not only reduces the complexity of the ACPICA initialization code, but in + * some cases (on systems with very large namespaces) it should reduce the + * kernel boot time as well. + */ + /******************************************************************************* * * FUNCTION: acpi_ev_gpe_initialize @@ -222,7 +238,7 @@ void acpi_ev_update_gpes(acpi_owner_id table_owner_id) acpi_status status = AE_OK; /* - * 2) Find any _Lxx/_Exx GPE methods that have just been loaded. + * Find any _Lxx/_Exx GPE methods that have just been loaded. * * Any GPEs that correspond to new _Lxx/_Exx methods are immediately * enabled. @@ -235,9 +251,9 @@ void acpi_ev_update_gpes(acpi_owner_id table_owner_id) return; } + walk_info.count = 0; walk_info.owner_id = table_owner_id; walk_info.execute_by_owner_id = TRUE; - walk_info.count = 0; /* Walk the interrupt level descriptor list */ @@ -298,7 +314,7 @@ void acpi_ev_update_gpes(acpi_owner_id table_owner_id) * xx - is the GPE number [in HEX] * * If walk_info->execute_by_owner_id is TRUE, we only execute examine GPE methods - * with that owner. + * with that owner. * ******************************************************************************/ -- cgit v1.2.3