Re: [PATCH v11 1/4] drm/msm/dp: do not initialize phy until plugin interrupt received

From: Stephen Boyd
Date: Thu Jan 13 2022 - 14:47:55 EST


Quoting Kuogee Hsieh (2022-01-13 09:51:42)
>
> On 1/12/2022 8:13 PM, Stephen Boyd wrote:
> >>>> - if (dp->usbpd->orientation == ORIENTATION_CC2)
> >>>> - flip = true;
> >>>> + dp_power_init(dp->power, false);
> >>>> + dp_ctrl_reset_irq_ctrl(dp->ctrl, true);
> >>>> +
> >>>> + /*
> >>>> + * eDP is the embedded primary display and has its own phy
> >>>> + * initialize phy immediately
> >>> Question still stands why we can't wait for hpd high from the eDP panel.
> >>> Also, I think "has its own phy" means that it's not part of a combo
> >>> USB+DP phy? Can you please clarify?
> >>>
> >>>> + */
> >>>> + if (dp->dp_display.connector_type == DRM_MODE_CONNECTOR_eDP)
> >>>> + dp_display_host_phy_init(dp);
> >>>>
> >>>> - dp_power_init(dp->power, flip);
> >>>> - dp_ctrl_host_init(dp->ctrl, flip, reset);
> >>>> dp_aux_init(dp->aux);
> >>>> dp->core_initialized = true;
> >>>> }
> >>>> @@ -1306,20 +1330,23 @@ static int dp_pm_resume(struct device *dev)
> >>>> dp->hpd_state = ST_DISCONNECTED;
> >>>>
> >>>> /* turn on dp ctrl/phy */
> >>>> - dp_display_host_init(dp, true);
> >>>> + dp_display_host_init(dp);
> >>>>
> >>>> dp_catalog_ctrl_hpd_config(dp->catalog);
> >>>>
> >>>> - /*
> >>>> - * set sink to normal operation mode -- D0
> >>>> - * before dpcd read
> >>>> - */
> >>>> - dp_link_psm_config(dp->link, &dp->panel->link_info, false);
> >>>>
> >>>> if (dp_catalog_link_is_connected(dp->catalog)) {
> >>>> + /*
> >>>> + * set sink to normal operation mode -- D0
> >>>> + * before dpcd read
> >>>> + */
> >>>> + dp_display_host_phy_init(dp);
> >>>> + dp_link_psm_config(dp->link, &dp->panel->link_info, false);
> >>>> sink_count = drm_dp_read_sink_count(dp->aux);
> >>>> if (sink_count < 0)
> >>>> sink_count = 0;
> >>>> +
> >>>> + dp_display_host_phy_exit(dp);
> >>> Why is the phy exited on resume when the link is still connected? Is
> >>> this supposed to be done only when the sink_count is 0? And how does
> >>> this interact with eDP where the phy is initialized by the call to
> >>> dp_display_host_init() earlier in this function.
> >>>
> >>>> }
> >>>>
> >>>> dp->link->sink_count = sink_count;
> > Any response to the above two comments?

??