[Intel-gfx] [DMC_REDESIGN_V2 03/14] drm/i915/bxt: release rpm reference if csr firmware failed to load.

[Imre Deak]

On Wed, 2015-10-14 at 11:59 +0530, Animesh Manna wrote:
> 
> On 9/30/2015 7:54 PM, Imre Deak wrote:
> > On ke, 2015-08-26 at 16:58 +0530, Animesh Manna wrote:
> >> Note that for bxt without dmc, display engine can go to lowest
> >> possible state (dc9), so releasing the rpm reference.
> >>
> >> Cc: Daniel Vetter <daniel.vetter at intel.com>
> >> Cc: Damien Lespiau <damien.lespiau at intel.com>
> >> Cc: Imre Deak <imre.deak at intel.com>
> >> Cc: Sunil Kamath <sunil.kamath at intel.com>
> >> Signed-off-by: Animesh Manna <animesh.manna at intel.com>
> >> ---
> >>   drivers/gpu/drm/i915/intel_csr.c | 2 +-
> >>   1 file changed, 1 insertion(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/gpu/drm/i915/intel_csr.c b/drivers/gpu/drm/i915/intel_csr.c
> >> index 75a775b..be388da 100644
> >> --- a/drivers/gpu/drm/i915/intel_csr.c
> >> +++ b/drivers/gpu/drm/i915/intel_csr.c
> >> @@ -392,7 +392,7 @@ static void finish_csr_load(const struct firmware *fw, void *context)
> >>   
> >>   	DRM_DEBUG_KMS("Finished loading %s\n", dev_priv->csr.fw_path);
> >>   out:
> >> -	if (fw_loaded)
> >> +	if (fw_loaded || IS_BROXTON(dev))
> >>   		intel_display_power_put(dev_priv, POWER_DOMAIN_INIT);
> > I don't think this is needed. We disable all display side runtime power
> > management if the firmware is not available. So no need to special case
> > this either imo.
> In display off case for broxton platform we can directly goto dc9 state 
> for which dmc is not needed.
> So, don't want to block runtime power management from display side.

We could also runtime suspend on Skylake without the DMC firmware. We
made the decision that we won't allow that, for no other reason than to
simplify the code. Doing that we don't need to check for the firmware
loaded status for instance to decide whether to enable DC5/6 or not
(which can be racy). So why would we now add the complexity for one
platform when we decidedly removed it from another?

--Imre

> 
> -Animesh
> >
> >>   	else
> >>   		intel_csr_load_status_set(dev_priv, FW_FAILED);
> >
>