On Fri, 2017-06-16 at 21:54 +0000, Navare, Manasi D wrote: > On Fri, 2017-06-16 at 21:26 +0000, Vivi, Rodrigo wrote: > > On Fri, 2017-06-16 at 21:21 +0000, Pandiyan, Dhinakaran wrote: > > > On Fri, 2017-06-16 at 14:12 -0700, Manasi Navare wrote: > > > > On Fri, Jun 16, 2017 at 08:58:25PM +0000, Pandiyan, Dhinakaran wrote: > > > > > On Fri, 2017-06-16 at 13:20 -0700, Rodrigo Vivi wrote: > > > > > > This missing case could be reached out on missing type or > > > > > > missing voltage. > > > > > > > > > > Should we even reach this far with a missing DDI type? > > > > > > > > > > -DK > > > > > > > > > > > > > Yes it is possible that we get into this situation if reading of > > > > the vccio voltage from PORT_COMP_DW3 returns a garbage value due > > > > to some corruption > > > > > > MISSING_CASE already logs that. > > > > > > > or lets say the type is something that is not supported on this > > > > platform. > > > > > > > But my question is, should we even be trying to program vswing > > > without knowing the ddi type or for an invalid type? > > > > we will reach the return; and avoid vswing programming. > > And logs will give us some information of what failed during modeset. > > > > Correct me if I am wrong, the only callers I could see are > intel_dp_set_signal_levels() and intel_ddi_pre_enable_hdmi(). In both cases, > the encoder type should have been set appropriately. My concern is that if we > are seeing some other type, we should be handling that before calling > cnl_ddi_vswing_program()
this is why I didn't get the missing case on the type if/else ;) we should never reach that case, but in case there is the missing case an extra debug message doesn't hurt... > > > But this debug message catches the condition where the type is correct but > the type and corresponding vccio voltage > Combination is wrong and the ddi tables are not present for that combination. > I definitely think it is a good idea to have this Debug print here in the > missing case. > > Manasi > > > > > > > > > > > > > > So let's add a debug > > > > > > message to make our lives easier whenever this might happen. > > > > > > > > > > > > Cc: Paulo Zanoni <[email protected]> > > > > > > Signed-off-by: Rodrigo Vivi <[email protected]> > > > > > > --- > > > > > > drivers/gpu/drm/i915/intel_ddi.c | 1 + > > > > > > 1 file changed, 1 insertion(+) > > > > > > > > > > > > diff --git a/drivers/gpu/drm/i915/intel_ddi.c > > > > > > b/drivers/gpu/drm/i915/intel_ddi.c > > > > > > index e66947a..c96c8d0 100644 > > > > > > --- a/drivers/gpu/drm/i915/intel_ddi.c > > > > > > +++ b/drivers/gpu/drm/i915/intel_ddi.c > > > > > > @@ -1802,6 +1802,7 @@ static void cnl_ddi_vswing_program(struct > > > > > > drm_i915_private *dev_priv, > > > > > > } > > > > > > > > > > > > if (ddi_translations == NULL) { > > > > > > + DRM_DEBUG_KMS("Missing DDI translation table for type > > > > > > %d > > > > > > +with voltage %d\n", type, voltage); > > > > > > MISSING_CASE(voltage); > > > > > > return; > > > > > > } > > > > > > > > Like Paulo suggested it would be better to use a switch statement > > > > for different vccio voltages and then have this in the default. What do > > > > you think? > > > > we don't need to iterate on voltages... and the switch for type > > wouldn't catch failures happening inside the functions where we > > actually pick the table. > > > > > > > > > > Manasi > > > > > > > > > > > > > > > > > > _______________________________________________ > > > > > Intel-gfx mailing list > > > > > [email protected] > > > > > https://lists.freedesktop.org/mailman/listinfo/intel-gfx > > > > _______________________________________________ > > > > Intel-gfx mailing list > > > > [email protected] > > > > https://lists.freedesktop.org/mailman/listinfo/intel-gfx > > > > > > > _______________________________________________ > > Intel-gfx mailing list > > [email protected] > > https://lists.freedesktop.org/mailman/listinfo/intel-gfx > > _______________________________________________ > Intel-gfx mailing list > [email protected] > https://lists.freedesktop.org/mailman/listinfo/intel-gfx _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
