[Intel-gfx] [PATCH 4/7] drm/i915: Add i830 "pipes power well"

[Maarten Lankhorst]

Op 01-06-17 om 16:36 schreef ville.syrjala at linux.intel.com:
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
>
> 830 more or less requires both pipes and DPLLs to remain on as long
> as either pipe is needed. However, when neither pipe is actually needed,
> we can save a bit of power by turning everything off. To do that we add
> a new "power well" that turns both pipes and DPLLs on and off in the
> right order. Seems to save ~50mW on my Fujitsu-Siemens Lifebook S6010.
>
> This also avoids having to abuse the load detection to force pipe A on
> at init time. That was never very robust, and it only worked for one
> pipe, whereas 830 really needs both pipes enabled. As a bonus the 830
> pipe quirk is now a bit more isolated from the rest of the mode setting
> infrastructure, which should mean that it's much less likely someone
> will accidentally break it in the future. The extra cost is of course
> slight code duplication, but that seems like a worthwile tradeoff here.
>
> v2; s/BIT/BIT_ULL/
>
> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> ---
>  drivers/gpu/drm/i915/intel_display.c    | 92 ++++++++++++++++++++++++++++++++-
>  drivers/gpu/drm/i915/intel_drv.h        |  2 +
>  drivers/gpu/drm/i915/intel_runtime_pm.c | 64 +++++++++++++++++++++++
>  3 files changed, 157 insertions(+), 1 deletion(-)

For patch 1-3:
Reviewed-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>

If you replace the remainder of crtc->config with pipe_config in
i9xx_crtc_enable and i9xx_crtc_disable and create a crtc_state for
disabling, won't it become possible to re-use some of the called
functions there instead of hardcoding the writes here?

For the rest of the series,

Acked-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>