On Tue, Sep 28, 2021 at 12:56:24AM +0300, Souza, Jose wrote:
> On Tue, 2021-09-21 at 03:23 +0300, Imre Deak wrote:
> > A follow-up change will select the TC-cold blocking power domain based
> > on the TypeC mode, prepare for that here.
> >
> > Also bring intel_tc_cold_requires_aux_pw() earlier to its logical place
> > for readability.
> >
> > No functional change.
> >
> > Cc: José Roberto de Souza <jose.so...@intel.com>
> > Signed-off-by: Imre Deak <imre.d...@intel.com>
> > ---
> > .../drm/i915/display/intel_display_types.h | 2 +
> > drivers/gpu/drm/i915/display/intel_tc.c | 63 +++++++++++--------
> > 2 files changed, 39 insertions(+), 26 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h
> > b/drivers/gpu/drm/i915/display/intel_display_types.h
> > index e9e806d90eec4..08a73ffded957 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> > +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> > @@ -1663,8 +1663,10 @@ struct intel_digital_port {
> > enum intel_display_power_domain ddi_io_power_domain;
> > intel_wakeref_t ddi_io_wakeref;
> > intel_wakeref_t aux_wakeref;
> > +
> > struct mutex tc_lock; /* protects the TypeC port mode */
> > intel_wakeref_t tc_lock_wakeref;
> > + enum intel_display_power_domain tc_lock_power_domain;
> > int tc_link_refcount;
> > bool tc_legacy_port:1;
> > char tc_port_name[8];
> > diff --git a/drivers/gpu/drm/i915/display/intel_tc.c
> > b/drivers/gpu/drm/i915/display/intel_tc.c
> > index 77b16a7c43466..24d2dc2e19a7d 100644
> > --- a/drivers/gpu/drm/i915/display/intel_tc.c
> > +++ b/drivers/gpu/drm/i915/display/intel_tc.c
> > @@ -48,8 +48,16 @@ bool intel_tc_port_in_legacy_mode(struct
> > intel_digital_port *dig_port)
> > return intel_tc_port_in_mode(dig_port, TC_PORT_LEGACY);
> > }
> >
> > +bool intel_tc_cold_requires_aux_pw(struct intel_digital_port *dig_port)
> > +{
> > + struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
> > +
> > + return (DISPLAY_VER(i915) == 11 && dig_port->tc_legacy_port) ||
> > + IS_ALDERLAKE_P(i915);
> > +}
> > +
> > static enum intel_display_power_domain
> > -tc_cold_get_power_domain(struct intel_digital_port *dig_port)
> > +tc_cold_get_power_domain(struct intel_digital_port *dig_port, enum
> > tc_port_mode mode)
> > {
> > if (intel_tc_cold_requires_aux_pw(dig_port))
> > return intel_legacy_aux_to_power_domain(dig_port->aux_ch);
> > @@ -58,23 +66,30 @@ tc_cold_get_power_domain(struct intel_digital_port
> > *dig_port)
> > }
> >
> > static intel_wakeref_t
> > -tc_cold_block(struct intel_digital_port *dig_port)
> > +tc_cold_block_in_mode(struct intel_digital_port *dig_port, enum
> > tc_port_mode mode,
> > + enum intel_display_power_domain *domain)
> > {
> > struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
> > - enum intel_display_power_domain domain;
> >
> > if (DISPLAY_VER(i915) == 11 && !dig_port->tc_legacy_port)
> > return 0;
> >
> > - domain = tc_cold_get_power_domain(dig_port);
> > - return intel_display_power_get(i915, domain);
> > + *domain = tc_cold_get_power_domain(dig_port, mode);
>
> I see problems with this approach.
>
> If there is a TC alt-mode is connected and current software state is
> TBT or disconnected it will not get the power domain to exit TC cold,
> what could case invalid reads of registers.
If the mode needs to be changed, like in the above cases, the power
domain required to exit TC cold will be taken.
> From the next patch commit message: 'For the ADL-P TBT mode the spec
> doesn't require blocking TC-cold by using the legacy AUX power
> domain'.
>
> It is not required for TBT but when there is nothing connected,
> hardware is not in TBT mode so it can still get into TC cold.
If there is nothing connected the required power domain will be taken to
exit TC cold.
> > +
> > + return intel_display_power_get(i915, *domain);
> > +}
> > +
> > +static intel_wakeref_t
> > +tc_cold_block(struct intel_digital_port *dig_port, enum
> > intel_display_power_domain *domain)
> > +{
> > + return tc_cold_block_in_mode(dig_port, dig_port->tc_mode, domain);
> > }
> >
> > static void
> > -tc_cold_unblock(struct intel_digital_port *dig_port, intel_wakeref_t
> > wakeref)
> > +tc_cold_unblock(struct intel_digital_port *dig_port, enum
> > intel_display_power_domain domain,
> > + intel_wakeref_t wakeref)
> > {
> > struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
> > - enum intel_display_power_domain domain;
> >
> > /*
> > * wakeref == -1, means some error happened saving save_depot_stack but
> > @@ -84,8 +99,7 @@ tc_cold_unblock(struct intel_digital_port *dig_port,
> > intel_wakeref_t wakeref)
> > if (wakeref == 0)
> > return;
> >
> > - domain = tc_cold_get_power_domain(dig_port);
> > - intel_display_power_put_async(i915, domain, wakeref);
> > + intel_display_power_put(i915, domain, wakeref);
> > }
> >
> > static void
> > @@ -98,7 +112,8 @@ assert_tc_cold_blocked(struct intel_digital_port
> > *dig_port)
> > return;
> >
> > enabled = intel_display_power_is_enabled(i915,
> > -
> > tc_cold_get_power_domain(dig_port));
> > +
> > tc_cold_get_power_domain(dig_port,
> > +
> > dig_port->tc_mode));
> > drm_WARN_ON(&i915->drm, !enabled);
> > }
> >
> > @@ -634,7 +649,8 @@ void intel_tc_port_sanitize(struct intel_digital_port
> > *dig_port)
> >
> > drm_WARN_ON(&i915->drm, dig_port->tc_mode != TC_PORT_DISCONNECTED);
> > if (active_links) {
> > - intel_wakeref_t tc_cold_wref = tc_cold_block(dig_port);
> > + enum intel_display_power_domain domain;
> > + intel_wakeref_t tc_cold_wref = tc_cold_block(dig_port, &domain);
> >
> > dig_port->tc_mode = intel_tc_port_get_current_mode(dig_port);
> >
> > @@ -644,7 +660,7 @@ void intel_tc_port_sanitize(struct intel_digital_port
> > *dig_port)
> > dig_port->tc_port_name, active_links);
> > intel_tc_port_link_init_refcount(dig_port, active_links);
> >
> > - tc_cold_unblock(dig_port, tc_cold_wref);
> > + tc_cold_unblock(dig_port, domain, tc_cold_wref);
> > }
> >
> > drm_dbg_kms(&i915->drm, "Port %s: sanitize mode (%s)\n",
> > @@ -673,15 +689,16 @@ bool intel_tc_port_connected(struct intel_encoder
> > *encoder)
> > {
> > struct intel_digital_port *dig_port = enc_to_dig_port(encoder);
> > bool is_connected;
> > + enum intel_display_power_domain domain;
> > intel_wakeref_t tc_cold_wref;
> >
> > intel_tc_port_lock(dig_port);
> > - tc_cold_wref = tc_cold_block(dig_port);
> > + tc_cold_wref = tc_cold_block(dig_port, &domain);
> >
> > is_connected = tc_port_live_status_mask(dig_port) &
> > BIT(dig_port->tc_mode);
> >
> > - tc_cold_unblock(dig_port, tc_cold_wref);
> > + tc_cold_unblock(dig_port, domain, tc_cold_wref);
> > intel_tc_port_unlock(dig_port);
> >
> > return is_connected;
> > @@ -698,15 +715,16 @@ static void __intel_tc_port_lock(struct
> > intel_digital_port *dig_port,
> > mutex_lock(&dig_port->tc_lock);
> >
> > if (!dig_port->tc_link_refcount) {
> > + enum intel_display_power_domain domain;
> > intel_wakeref_t tc_cold_wref;
> >
> > - tc_cold_wref = tc_cold_block(dig_port);
> > + tc_cold_wref = tc_cold_block(dig_port, &domain);
> >
> > if (force_disconnect || intel_tc_port_needs_reset(dig_port))
> > intel_tc_port_reset_mode(dig_port, required_lanes,
> > force_disconnect);
> >
> > - tc_cold_unblock(dig_port, tc_cold_wref);
> > + tc_cold_unblock(dig_port, domain, tc_cold_wref);
> > }
> >
> > drm_WARN_ON(&i915->drm, dig_port->tc_mode == TC_PORT_DISCONNECTED);
> > @@ -775,6 +793,7 @@ void intel_tc_port_put_link(struct intel_digital_port
> > *dig_port)
> > static bool
> > tc_has_modular_fia(struct drm_i915_private *i915, struct
> > intel_digital_port *dig_port)
> > {
> > + enum intel_display_power_domain domain;
> > intel_wakeref_t wakeref;
> > u32 val;
> >
> > @@ -782,9 +801,9 @@ tc_has_modular_fia(struct drm_i915_private *i915,
> > struct intel_digital_port *dig
> > return false;
> >
> > mutex_lock(&dig_port->tc_lock);
> > - wakeref = tc_cold_block(dig_port);
> > + wakeref = tc_cold_block(dig_port, &domain);
> > val = intel_uncore_read(&i915->uncore, PORT_TX_DFLEXDPSP(FIA1));
> > - tc_cold_unblock(dig_port, wakeref);
> > + tc_cold_unblock(dig_port, domain, wakeref);
> > mutex_unlock(&dig_port->tc_lock);
> >
> > drm_WARN_ON(&i915->drm, val == 0xffffffff);
> > @@ -829,11 +848,3 @@ void intel_tc_port_init(struct intel_digital_port
> > *dig_port, bool is_legacy)
> > dig_port->tc_link_refcount = 0;
> > tc_port_load_fia_params(i915, dig_port);
> > }
> > -
> > -bool intel_tc_cold_requires_aux_pw(struct intel_digital_port *dig_port)
> > -{
> > - struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
> > -
> > - return (DISPLAY_VER(i915) == 11 && dig_port->tc_legacy_port) ||
> > - IS_ALDERLAKE_P(i915);
> > -}
>
