linux-stable/drivers/gpu/drm/i915/display/intel_tc.h
Imre Deak 3e0abc7661 drm/i915/tc: Fix TypeC PHY connect/disconnect logic on ADL-P
So far TC-cold was blocked only for the duration of TypeC mode resets.
The DP-alt and legacy modes require TC-cold to be blocked also whenever
the port is in use (AUX transfers, enable modeset), and this was ensured
by the held PHY ownership flag. On ADL-P this doesn't work, since the
PHY ownership flag is in a register backed by the PW#2 power well.
Whenever this power well is disabled the ownership flag is cleared by
the HW under the driver.

The only way to cleanly release and re-acquire the PHY ownership flag
and also allow for power saving (by disabling the display power wells
and reaching DC5/6 states) is to hold the TC-cold blocking power domains
while the PHY is connected and disconnect/reconnect the PHY on-demand
around AUX transfers and modeset enable/disables. Let's do that,
disconnecting a PHY with a 1 sec delay after it becomes idle. For
consistency do this on all platforms and TypeC modes.

v2: Add tc_mode!=disconnected and phy_is_owned asserts to
    __intel_tc_port_lock().

Cc: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210929132833.2253961-6-imre.deak@intel.com
2021-09-29 23:58:04 +03:00

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C

/* SPDX-License-Identifier: MIT */
/*
* Copyright © 2019 Intel Corporation
*/
#ifndef __INTEL_TC_H__
#define __INTEL_TC_H__
#include <linux/mutex.h>
#include <linux/types.h>
struct intel_digital_port;
struct intel_encoder;
bool intel_tc_port_in_tbt_alt_mode(struct intel_digital_port *dig_port);
bool intel_tc_port_in_dp_alt_mode(struct intel_digital_port *dig_port);
bool intel_tc_port_in_legacy_mode(struct intel_digital_port *dig_port);
bool intel_tc_port_connected(struct intel_encoder *encoder);
u32 intel_tc_port_get_lane_mask(struct intel_digital_port *dig_port);
u32 intel_tc_port_get_pin_assignment_mask(struct intel_digital_port *dig_port);
int intel_tc_port_fia_max_lane_count(struct intel_digital_port *dig_port);
void intel_tc_port_set_fia_lane_count(struct intel_digital_port *dig_port,
int required_lanes);
void intel_tc_port_sanitize(struct intel_digital_port *dig_port);
void intel_tc_port_lock(struct intel_digital_port *dig_port);
void intel_tc_port_unlock(struct intel_digital_port *dig_port);
void intel_tc_port_flush_work(struct intel_digital_port *dig_port);
void intel_tc_port_get_link(struct intel_digital_port *dig_port,
int required_lanes);
void intel_tc_port_put_link(struct intel_digital_port *dig_port);
bool intel_tc_port_ref_held(struct intel_digital_port *dig_port);
void intel_tc_port_init(struct intel_digital_port *dig_port, bool is_legacy);
bool intel_tc_cold_requires_aux_pw(struct intel_digital_port *dig_port);
#endif /* __INTEL_TC_H__ */