On Wed, Sep 18, 2019 at 10:51:54AM +0200, Maarten Lankhorst wrote: > Op 17-09-2019 om 18:37 schreef Manasi Navare: > > On Tue, Sep 17, 2019 at 05:04:28PM +0200, Maarten Lankhorst wrote: > >> Op 09-09-2019 om 05:43 schreef Manasi Navare: > >>> This clears the transcoder port sync bits of the TRANS_DDI_FUNC_CTL2 > >>> register during crtc_disable(). > >>> > >>> Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > >>> Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx> > >>> Cc: Matt Roper <matthew.d.roper@xxxxxxxxx> > >>> Cc: Jani Nikula <jani.nikula@xxxxxxxxx> > >>> Signed-off-by: Manasi Navare <manasi.d.navare@xxxxxxxxx> > >>> --- > >>> drivers/gpu/drm/i915/display/intel_display.c | 23 ++++++++++++++++++++ > >>> 1 file changed, 23 insertions(+) > >>> > >>> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c > >>> index 351c90ad7059..07deb0b93f5c 100644 > >>> --- a/drivers/gpu/drm/i915/display/intel_display.c > >>> +++ b/drivers/gpu/drm/i915/display/intel_display.c > >>> @@ -4438,6 +4438,26 @@ static void icl_enable_trans_port_sync(const struct intel_crtc_state *crtc_state > >>> trans_ddi_func_ctl2_val); > >>> } > >>> > >>> +static void icl_disable_transcoder_port_sync(const struct intel_crtc_state *old_crtc_state) > >>> +{ > >>> + struct intel_crtc *crtc = to_intel_crtc(old_crtc_state->base.crtc); > >>> + struct drm_i915_private *dev_priv = to_i915(crtc->base.dev); > >>> + i915_reg_t reg; > >>> + u32 trans_ddi_func_ctl2_val; > >>> + > >>> + if (old_crtc_state->master_transcoder == INVALID_TRANSCODER) > >>> + return; > >>> + > >>> + DRM_DEBUG_KMS("Disabling Transcoder Port Sync on Slave Transcoder %s\n", > >>> + transcoder_name(old_crtc_state->cpu_transcoder)); > >>> + > >>> + reg = TRANS_DDI_FUNC_CTL2(old_crtc_state->cpu_transcoder); > >>> + 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); > >>> +} > >>> + > >> Would anything break if we just wrote 0 here? > > We dont want to accidently reset other bits in the register which are for DSI and not used currently but > > to make this function more future proof, I have avoided writing a 0 > > > > But if you strongly feel against this, I can switch this to writing 0 directly. > > We overwrite func_ctl2 in enable_port_sync so it makes sense to do the same in disable. :) Yes as per the reviews on the enable patch, the RMW was not recommended, so even here I will just overwrite with ~(PORT_SYNC_MODE_ENABLE | PORT_SYNC_MODE_MASTER_SELECT_MASK); This sounds good? Manasi > _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx