Re: [PATCH v2 12/23] drm/i915: Sanitize the TypeC connect/detect sequences

Ville Syrjälä
2019-06-26T11:51:47Z

On Tue, Jun 25, 2019 at 09:30:43PM +0300, Imre Deak wrote:
> On Tue, Jun 25, 2019 at 04:42:01PM +0300, Ville Syrjälä wrote:
> > On Thu, Jun 20, 2019 at 05:05:49PM +0300, Imre Deak wrote:
> > > Make the order during detection more consistent: first reset the TypeC
> > > port mode if needed (adding new helpers for this), then detect any
> > > connected sink.
> > >
> > > To check if a port mode reset is needed determine first the target port
> > > mode based on the live status if a sink is already connected or the
> > > PHY status complete flag otherwise.
> > >
> > > Add a WARN in legacy mode if unexpectedly we can't set the unsafe mode
> > > or if the FIA doesn't provide the 4 lanes required.
> > >
> > > Cc: José Roberto de Souza <jose.souza@intel.com>
> > > Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> > > Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
> > > Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
> > > Signed-off-by: Imre Deak <imre.deak@intel.com>
> > > ---
> > > drivers/gpu/drm/i915/display/intel_tc.c | 96 ++++++++++++-------------
> > > 1 file changed, 47 insertions(+), 49 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/i915/display/intel_tc.c b/drivers/gpu/drm/i915/display/intel_tc.c
> > > index fffe4c4a6602..ed2253b21b09 100644
> > > --- a/drivers/gpu/drm/i915/display/intel_tc.c
> > > +++ b/drivers/gpu/drm/i915/display/intel_tc.c
> > > @@ -172,41 +172,43 @@ static bool icl_tc_phy_set_safe_mode(struct intel_digital_port *dig_port,
> > > * will require a lot of coordination with user space and thorough testing for
> > > * the extra possible cases.
> > > */
> > > -static bool icl_tc_phy_connect(struct intel_digital_port *dig_port)
> > > +static void icl_tc_phy_connect(struct intel_digital_port *dig_port)
> > > {
> > > - u32 live_status_mask;
> > > -
> > > - if (dig_port->tc_mode != TC_PORT_LEGACY &&
> > > - dig_port->tc_mode != TC_PORT_DP_ALT)
> > > - return true;
> > > -
> > > if (!icl_tc_phy_status_complete(dig_port)) {
> > > DRM_DEBUG_KMS("Port %s: PHY not ready\n",
> > > dig_port->tc_port_name);
> > > - WARN_ON(dig_port->tc_legacy_port);
> >
> > Are we expecting legacy ports to indicate "not complete"?
>
> Yes, I think that may happen if during driver loading/resume the sink is
> not connected, VBT says the port is legacy, but the firmware would
> happen to set the 'phy complete' flag only with some delay. In that case
> we'd try to connect the PHY from intel_tc_port_sanitize(), later in the
> patchset, so 'phy complete' could be still unset here. We'd only connect
> the PHY then when the sink gets plugged.

OK.

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

>
> >
> > > - return false;
> > > + goto out_set_tbt_alt_mode;
> > > }
> > >
> > > - if (!icl_tc_phy_set_safe_mode(dig_port, false))
> > > - return false;
> > > + if (!icl_tc_phy_set_safe_mode(dig_port, false) &&
> > > + !WARN_ON(dig_port->tc_legacy_port))
> > > + goto out_set_tbt_alt_mode;
> > >
> > > - if (dig_port->tc_mode == TC_PORT_LEGACY)
> > > - return true;
> > > + if (dig_port->tc_legacy_port) {
> > > + WARN_ON(intel_tc_port_fia_max_lane_count(dig_port) != 4);
> > > + dig_port->tc_mode = TC_PORT_LEGACY;
> > >
> > > - live_status_mask = tc_port_live_status_mask(dig_port);
> > > + return;
> > > + }
> > >
> > > /*
> > > * Now we have to re-check the live state, in case the port recently
> > > * became disconnected. Not necessary for legacy mode.
> > > */
> > > - if (!(live_status_mask & BIT(TC_PORT_DP_ALT))) {
> > > + if (!(tc_port_live_status_mask(dig_port) & BIT(TC_PORT_DP_ALT))) {
> > > DRM_DEBUG_KMS("Port %s: PHY sudden disconnect\n",
> > > dig_port->tc_port_name);
> > > - icl_tc_phy_disconnect(dig_port);
> > > - return false;
> > > + goto out_set_safe_mode;
> > > }
> > >
> > > - return true;
> > > + dig_port->tc_mode = TC_PORT_DP_ALT;
> > > +
> > > + return;
> > > +
> > > +out_set_safe_mode:
> > > + icl_tc_phy_set_safe_mode(dig_port, true);
> > > +out_set_tbt_alt_mode:
> > > + dig_port->tc_mode = TC_PORT_TBT_ALT;
> > > }
> > >
> > > /*
> > > @@ -227,27 +229,37 @@ void icl_tc_phy_disconnect(struct intel_digital_port *dig_port)
> > > default:
> > > MISSING_CASE(dig_port->tc_mode);
> > > }
> > > +}
> > >
> > > - DRM_DEBUG_KMS("Port %s: mode %s disconnected\n",
> > > - dig_port->tc_port_name,
> > > - tc_port_mode_name(dig_port->tc_mode));
> > > +static enum tc_port_mode
> > > +intel_tc_port_get_target_mode(struct intel_digital_port *dig_port)
> > > +{
> > > + u32 live_status_mask = tc_port_live_status_mask(dig_port);
> > > +
> > > + if (live_status_mask)
> > > + return fls(live_status_mask) - 1;
> > > +
> > > + return icl_tc_phy_status_complete(dig_port) &&
> > > + dig_port->tc_legacy_port ? TC_PORT_LEGACY :
> > > + TC_PORT_TBT_ALT;
> > > }
> > >
> > > -static void icl_update_tc_port_type(struct drm_i915_private *dev_priv,
> > > - struct intel_digital_port *intel_dig_port,
> > > - u32 live_status_mask)
> > > +static void intel_tc_port_reset_mode(struct intel_digital_port *dig_port)
> > > {
> > > - enum tc_port_mode old_mode = intel_dig_port->tc_mode;
> > > + enum tc_port_mode old_tc_mode = dig_port->tc_mode;
> > >
> > > - if (!live_status_mask)
> > > - return;
> > > + icl_tc_phy_disconnect(dig_port);
> > > + icl_tc_phy_connect(dig_port);
> > >
> > > - intel_dig_port->tc_mode = fls(live_status_mask) - 1;
> > > + DRM_DEBUG_KMS("Port %s: TC port mode reset (%s -> %s)\n",
> > > + dig_port->tc_port_name,
> > > + tc_port_mode_name(old_tc_mode),
> > > + tc_port_mode_name(dig_port->tc_mode));
> > > +}
> > >
> > > - if (old_mode != intel_dig_port->tc_mode)
> > > - DRM_DEBUG_KMS("Port %s: port has mode %s\n",
> > > - intel_dig_port->tc_port_name,
> > > - tc_port_mode_name(intel_dig_port->tc_mode));
> > > +static bool intel_tc_port_needs_reset(struct intel_digital_port *dig_port)
> > > +{
> > > + return intel_tc_port_get_target_mode(dig_port) != dig_port->tc_mode;
> > > }
> > >
> > > /*
> > > @@ -262,24 +274,10 @@ static void icl_update_tc_port_type(struct drm_i915_private *dev_priv,
> > > */
> > > bool intel_tc_port_connected(struct intel_digital_port *dig_port)
> > > {
> > > - struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
> > > - u32 live_status_mask = tc_port_live_status_mask(dig_port);
> > > -
> > > - /*
> > > - * The spec says we shouldn't be using the ISR bits for detecting
> > > - * between TC and TBT. We should use DFLEXDPSP.
> > > - */
> > > - if (!live_status_mask && !dig_port->tc_legacy_port) {
> > > - icl_tc_phy_disconnect(dig_port);
> > > -
> > > - return false;
> > > - }
> > > -
> > > - icl_update_tc_port_type(dev_priv, dig_port, live_status_mask);
> > > - if (!icl_tc_phy_connect(dig_port))
> > > - return false;
> > > + if (intel_tc_port_needs_reset(dig_port))
> > > + intel_tc_port_reset_mode(dig_port);
> > >
> > > - return true;
> > > + return tc_port_live_status_mask(dig_port) & BIT(dig_port->tc_mode);
> > > }
> > >
> > > void intel_tc_port_init(struct intel_digital_port *dig_port, bool is_legacy)
> > > --
> > > 2.17.1
> >
> > --
> > Ville Syrjälä
> > Intel

--
Ville Syrjälä
Intel