Re: [RFC PATCH] ACPICA: Improve GPE detect

["Rafael J. Wysocki" <rjw@sisk.pl>]

On Friday, December 17, 2010, Moore, Robert wrote:
> They are 8 enable bits per gpe_register.

That's correct, sorry.

> So, may as well OR them together first and use a single compare.

Exactly.


> -----Original Message-----
> From: Rafael J. Wysocki [mailto:rjw@sisk.pl] 
> Sent: Friday, December 17, 2010 12:23 PM
> To: Moore, Robert
> Cc: Lin, Ming M; lenb; linux-acpi
> Subject: Re: [RFC PATCH] ACPICA: Improve GPE detect
> 
> On Wednesday, December 15, 2010, Moore, Robert wrote:
> > +			if (!gpe_register_info->enable_for_run &&
> > +				!gpe_register_info->enable_for_wake) {
> > 
> > I would bitwise OR them together first
> > 
> > +			if (!(gpe_register_info->enable_for_run |
> > +				gpe_register_info->enable_for_wake)) {
> 
> Well, I think a || would be a little better (they are treated as flags rather
> than bit patterns everywhere else), but I generally agree.
> 
> The patch looks good apart from this.
> 
> Thanks,
> Rafael
> 
> 
> > -----Original Message-----
> > From: Lin, Ming M 
> > Sent: Wednesday, December 15, 2010 12:00 AM
> > To: Rafael J. Wysocki
> > Cc: lenb; Moore, Robert; linux-acpi
> > Subject: [RFC PATCH] ACPICA: Improve GPE detect
> > 
> > Hi, Rafael
> > 
> > Currently, the ACPICA GPE interrupt handler reads all the GPE registers to
> > detect which GPEs, if any, have fired. This is done on each and every SCI,
> > since there is no way to know up front if any GPEs have been raised.
> > 
> > However, since ACPICA internally keeps a GPE enable mask for every GPE
> > register, it may be possible to ignore any GPE registers whose internal
> > GPE enable mask is zero. This would eliminate reading the status and enable
> > registers for that particular GPE register pair.
> > 
> > http://www.acpica.org/bugzilla/show_bug.cgi?id=884
> > 
> > I have tested suspend/resume and it works OK.
> > What do you think about below simple patch?
> > 
> > Thanks.
> > ---
> >  drivers/acpi/acpica/evgpe.c |    8 ++++++++
> >  1 files changed, 8 insertions(+), 0 deletions(-)
> > 
> > diff --git a/drivers/acpi/acpica/evgpe.c b/drivers/acpi/acpica/evgpe.c
> > index 7c339d3..49fab43 100644
> > --- a/drivers/acpi/acpica/evgpe.c
> > +++ b/drivers/acpi/acpica/evgpe.c
> > @@ -373,6 +373,14 @@ u32 acpi_ev_gpe_detect(struct acpi_gpe_xrupt_info * gpe_xrupt_list)
> >  
> >  			gpe_register_info = &gpe_block->register_info[i];
> >  
> > +			if (!gpe_register_info->enable_for_run &&
> > +				!gpe_register_info->enable_for_wake) {
> > +
> > +				/* Disabled for both "runtime" and "wakeup", move on */
> > +
> > +				continue;
> > +			}
> > +
> >  			/* Read the Status Register */
> >  
> >  			status =
> > 
> > 
> > 
> 
>