On Fri, 22 Apr 2011 11:05:17 +0800 "Wang, Yong Y" <[email protected]> wrote:
> > -----Original Message----- > > From: [email protected] > > [mailto:[email protected]] On Behalf Of Kristen Carlson > > Accardi > > Sent: Thursday, April 21, 2011 5:07 AM > > To: [email protected] > > Subject: [Meego-kernel] [PATCH 1/2] pmu: fix debug for graphics_is_in_d3 > > > > use the correct port to check graphics > > > > Signed-off-by: Kristen Carlson Accardi <[email protected]> > > --- > > arch/x86/platform/mrst/pmu.c | 2 +- > > 1 files changed, 1 insertions(+), 1 deletions(-) > > > > diff --git a/arch/x86/platform/mrst/pmu.c b/arch/x86/platform/mrst/pmu.c > > index daef72c..ab26663 100644 > > --- a/arch/x86/platform/mrst/pmu.c > > +++ b/arch/x86/platform/mrst/pmu.c > > @@ -114,7 +114,7 @@ static struct mrst_device *pci_id_2_mrst_dev(u16 > > pci_dev_num) > > */ > > static int graphics_is_in_d3(void) > > { > > - return (0xC == (0xC & inl(0x1130))); /* DEBUG only */ > > + return (0xC == (0xC & inl(0x1120))); /* DEBUG only */ > > } > > > > /** > > Hi Kristen, > > 0x1130, i.e. PM subsystem status register, is the correct port to check gfx > status. 0x1120 is PM subsystem configuration register. Gfx driver's runtime > code writes to 0x1120 to put gfx into low power state. Whether the gfx driver > succeeds to do that will be reflected in PM subsystem status register which > is port 0x1130. Hope this clarifies. > > Thanks > -Yong > Interesting - because when we write to 0x1120 and read from 0x1130 the write is never reflected in the status and graphics_is_in_d3() never returns true. I wonder if that means that regardless of writes to 0x1120 gfx never actually succeeds to go into a lower power state? _______________________________________________ MeeGo-kernel mailing list [email protected] http://lists.meego.com/listinfo/meego-kernel
