On Fri, Dec 13, 2019 at 12:40:13PM -0800, Manasi Navare wrote: > On Fri, Dec 13, 2019 at 10:06:37PM +0200, Ville Syrjälä wrote: > > On Wed, Dec 11, 2019 at 01:14:25PM -0800, Manasi Navare wrote: > > > While clearing the Ports ync mode enable and master select bits > > > we need to make sure that we perform a RMW for disable else > > > it sets the other bits casuing unwanted sideeffects. > > > > > > Bugzilla: https://gitlab.freedesktop.org/drm/intel/issues/5 > > > Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > > > Cc: Jani Nikula <jani.nikula@xxxxxxxxx> > > > Fixes: 51528afe7c5e ("drm/i915/display/icl: Disable transcoder port sync as part of crtc_disable() sequence") > > > Signed-off-by: Manasi Navare <manasi.d.navare@xxxxxxxxx> > > > --- > > > drivers/gpu/drm/i915/display/intel_display.c | 3 ++- > > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > > > diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c > > > index c0a2dab3fe67..3fccda0f1f36 100644 > > > --- a/drivers/gpu/drm/i915/display/intel_display.c > > > +++ b/drivers/gpu/drm/i915/display/intel_display.c > > > @@ -4599,7 +4599,8 @@ static void icl_disable_transcoder_port_sync(const struct intel_crtc_state *old_ > > > transcoder_name(old_crtc_state->cpu_transcoder)); > > > > > > reg = TRANS_DDI_FUNC_CTL2(old_crtc_state->cpu_transcoder); > > > - trans_ddi_func_ctl2_val = ~(PORT_SYNC_MODE_ENABLE | > > > + trans_ddi_func_ctl2_val = I915_READ(reg); > > > + trans_ddi_func_ctl2_val &= ~(PORT_SYNC_MODE_ENABLE | > > > PORT_SYNC_MODE_MASTER_SELECT_MASK); > > > I915_WRITE(reg, trans_ddi_func_ctl2_val); > > > > I915_WRITE(TRANS_DDI_FUNC_CTL2, 0); > > So not even consider the other values that might have been set in this reg? > You would prefer setting this to 0 directly? > Right now i do see that no other bits are set, but things can change when we > start using DSI port sync mode or genlock mode etc. No point in making it more complicated than it has to be. In fact after the series I just posted we should probably just suck this whole thing into intel_ddi_{enable,disable}_transcoder_func() since on older platforms these bits live in TRANS_DDI_FUNC_CTL itself. > > Manasi > > > > > > } > > > -- > > > 2.19.1 > > > > -- > > Ville Syrjälä > > Intel -- Ville Syrjälä Intel _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
