On Tue, 2008-07-15 at 10:41 +0800, Zhao Yakui wrote: > On Mon, 2008-07-14 at 12:39 +0200, Thomas Renninger wrote: > > On Monday 14 July 2008 09:39:34 Zhao Yakui wrote: > > > From: Zhao Yakui <yakui.zhao@xxxxxxxxx> > > > > > > Maybe the incorrect power state is returned on the bogus bios, which > > > is different with the real power state. For example: the bios returns D0 > > > state and the real power state is D3. OS expects to set the device to D0 > > > state. In such case if OS uses the power state returned by the BIOS and > > > checks the device power state very strictly in power transition, the device > > > can't be transited to the correct power state. > > > > > > So the boot option of "acpi.power_nocheck=1" is added to avoid checking > > > the device power state in the course of device power transition. > > > > > > http://bugzilla.kernel.org/show_bug.cgi?id=8049 > > > http://bugzilla.kernel.org/show_bug.cgi?id=11000 > > > > > > Signed-off-by: Zhao Yakui <yakui.zhao@xxxxxxxxx> > > > Signed-off-by: Zhang Rui <rui.zhang@xxxxxxxxx> > > > Signed-off-by: Li Shaohua <shaohua.li@xxxxxxxxx> > > > > > > --- > > > Documentation/kernel-parameters.txt | 7 ++++++ > > > drivers/acpi/bus.c | 14 +++++++++++- > > > drivers/acpi/power.c | 42 > > > ++++++++++++++++++++++++++---------- include/acpi/acpi_drivers.h | > > > 1 > > > 4 files changed, 52 insertions(+), 12 deletions(-) > > > > > > Index: linux-2.6/Documentation/kernel-parameters.txt > > > =================================================================== > > > --- linux-2.6.orig/Documentation/kernel-parameters.txt > > > +++ linux-2.6/Documentation/kernel-parameters.txt > > > @@ -224,6 +224,13 @@ and is between 256 and 4096 characters. > > > The number can be in decimal or prefixed with 0x in hex. > > > Warning: Many of these options can produce a lot of > > > output and make your system unusable. Be very careful. > > > + acpi.power_nocheck= [HW,ACPI] > > > + Format: 1/0 enable/disable the check of power state. > > > + On some bogus BIOS the _PSC object/_STA object of > > > + power resource can't return the correct device power > > > + state. In such case it is unneccessary to check its > > > + power state again in power transition. > > > + 1 : disable the power state check > > > > > > acpi_pm_good [X86-32,X86-64] > > > Override the pmtimer bug detection: force the kernel > > > Index: linux-2.6/drivers/acpi/power.c > > > =================================================================== > > > --- linux-2.6.orig/drivers/acpi/power.c > > > +++ linux-2.6/drivers/acpi/power.c > > > @@ -54,6 +54,14 @@ ACPI_MODULE_NAME("power"); > > > #define ACPI_POWER_RESOURCE_STATE_OFF 0x00 > > > #define ACPI_POWER_RESOURCE_STATE_ON 0x01 > > > #define ACPI_POWER_RESOURCE_STATE_UNKNOWN 0xFF > > > + > > > +#ifdef MODULE_PARAM_PREFIX > > > +#undef MODULE_PARAM_PREFIX > > > +#endif > > > +#define MODULE_PARAM_PREFIX "acpi." > > > +int acpi_power_nocheck; > > > +module_param_named(power_nocheck, acpi_power_nocheck, bool, 000); > > > + > > > static int acpi_power_add(struct acpi_device *device); > > > static int acpi_power_remove(struct acpi_device *device, int type); > > > static int acpi_power_resume(struct acpi_device *device); > > > @@ -228,12 +236,18 @@ static int acpi_power_on(acpi_handle han > > > if (ACPI_FAILURE(status)) > > > return -ENODEV; > > > > > > - result = acpi_power_get_state(resource->device->handle, &state); > > > - if (result) > > > - return result; > > > - if (state != ACPI_POWER_RESOURCE_STATE_ON) > > > - return -ENOEXEC; > > > - > > > + if (!acpi_power_nocheck) { > > > + /* > > > + * If acpi_power_nocheck is set, it is unnecessary to check > > > + * the power state after power transition. > > > + */ > > > + result = acpi_power_get_state(resource->device->handle, > > > + &state); > > > + if (result) > > > + return result; > > > + if (state != ACPI_POWER_RESOURCE_STATE_ON) > > > + return -ENOEXEC; > > > + } > > > /* Update the power resource's _device_ power state */ > > > resource->device->power.state = ACPI_STATE_D0; > > > > A fat ACPI_EXCEPTION that the power state is bogus and already point to the > > acpi.power_nocheck boot param before returning -ENOEXEC would help to find > > this boot param for affected machines? > Good idea. Before the -ENOEXEC is returned, had better print some > warning message and suggest trying the boot option of > acpi.power_nocheck=1. > > I wonder whether this (acpi.power_nocheck=1) could even get the default, maybe > > after waiting for reponse about how many machines really show this and why... Yes. that's what we want to do at the beginning. Currently, using acpi.power_nocheck=1 by default without many tests is too aggressive. But some warning messages being printed out when the driver doesn't work with acpi.power_nocheck=0 will help a lot. :) 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
