[Intel-gfx] [PATCH] drm/i915: Turn off hsync and vsync on ADPA when disabling crt

[Patrik Jakobsson]

On Tue, Mar 5, 2013 at 3:59 PM, Ville Syrjälä
<ville.syrjala at linux.intel.com> wrote:
> On Tue, Mar 05, 2013 at 03:33:26PM +0100, Patrik Jakobsson wrote:
>> > Accroding to the docs these bits don't exist on PCH platforms.
>> > intel_crt_dpms() already has a check for this, so I suppose
>> > intel_disable_crt() should have one too.
>> >
>> > Also I noticed that we seem to have the hsync and vsync disable
>> > bits reversed. At least that's what the docs are telling me.
>>
>> The PCH check just forces suspend and standby to off and we're only doing dpms
>> off in intel_disable_crt() so no need to check it there.
>
> You're right. I assumed that the check would somehow avoid setting
> these bits too, but it doesn't. So I guess we don't really care
> that they don't exist.
>
>> I'm looking at the 965/G35 PRM and the "sync disable" are defined correctly but
>> used incorrectly in intel_disable_crt(). That's what my patch fixes. I haven't
>> checked the other PRMs. Is it different on newer hardware?
>
> This is what the docs say:
>
> 11:10 Monitor DPMS: (for CRT port) ...
> ...
> 00 = ... (will not affect sync pulses)
> 01 = ... (HSYNC pulses, VSYNC does not)
> 10 = ... (VSYNC pulses, HSYNC does not)
> 11 = ... (Neither HSYNC nor VSYNC pulses)
>
> These are our definintions:
>
> #define   ADPA_VSYNC_CNTL_DISABLE (1<<11)
> #define   ADPA_HSYNC_CNTL_DISABLE (1<<10)
>
> As you can see they don't match.

Aha, you're right. I thought you meant disable = 0 and enable = 1.
So when we're doing suspend we are in fact doing standby and vice versa.

-Patrik