[Intel-gfx] [PATCH v3 4/8] drm/i915/tc/icl: Implement TC cold sequences
Imre Deak
imre.deak at intel.com
Tue Apr 7 22:03:46 UTC 2020
On Tue, Apr 07, 2020 at 02:39:56PM -0700, José Roberto de Souza wrote:
> This is required for legacy/static TC ports as IOM is not aware of
> the connection and will not trigger the TC cold exit.
>
> Just request PCODE to exit TCCOLD is not enough as it could enter
> again before driver makes use of the port, to prevent it BSpec states
> that aux powerwell should be held.
>
> So here embedding the TC cold exit sequence into ICL aux enable,
> it will enable aux and then request TC cold to exit.
>
> The TC cold block(exit and aux hold) and unblock was added to some
> exported TC functions for the others and to access PHY registers,
> callers should enable and keep aux powerwell enabled during access.
>
> Also adding TC cold check and warnig in tc_port_load_fia_params() as
> at this point of the driver initialization we can't request power
> wells, if we get this warning we will need to figure out how to handle
> it.
>
> v2:
> - moved ICL TC cold exit function to intel_display_power
> - using dig_port->tc_legacy_port to only execute sequences for legacy
> ports, hopefully VBTs will have this right
> - fixed check to call _hsw_power_well_continue_enable()
> - calling _hsw_power_well_continue_enable() unconditionally in
> icl_tc_phy_aux_power_well_enable(), if needed we will surpress timeout
> warnings of TC legacy ports
> - only blocking TC cold around fia access
>
> v3:
> - added timeout of 5msec to not loop forever if
> sandybridge_pcode_write_timeout() keeps returning -EAGAIN
> returning -EAGAIN in in icl_tc_cold_exit()
> - removed leftover tc_cold_wakeref
> - added one msec sleep when PCODE returns -EAGAIN
>
> BSpec: 21750
> Fixes: https://gitlab.freedesktop.org/drm/intel/issues/1296
> Cc: Imre Deak <imre.deak at intel.com>
> Cc: Cooper Chiou <cooper.chiou at intel.com>
> Cc: Kai-Heng Feng <kai.heng.feng at canonical.com>
> Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
> ---
> .../drm/i915/display/intel_display_power.c | 24 ++++++-
> drivers/gpu/drm/i915/display/intel_tc.c | 64 +++++++++++++++++--
> drivers/gpu/drm/i915/i915_reg.h | 1 +
> 3 files changed, 82 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_display_power.c b/drivers/gpu/drm/i915/display/intel_display_power.c
> index 1cd271d0f114..2d7b2999561a 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_power.c
> +++ b/drivers/gpu/drm/i915/display/intel_display_power.c
> @@ -575,6 +575,27 @@ static void icl_tc_port_assert_ref_held(struct drm_i915_private *dev_priv,
>
> #define TGL_AUX_PW_TO_TC_PORT(pw_idx) ((pw_idx) - TGL_PW_CTL_IDX_AUX_TC1)
>
> +static void icl_tc_cold_exit(struct drm_i915_private *i915)
> +{
> + const ktime_t timeout = ktime_add_ms(ktime_get_raw(), 5);
> + int ret;
> +
> + do {
> + ret = sandybridge_pcode_write_timeout(i915,
> + ICL_PCODE_EXIT_TCCOLD,
> + 0, 250, 1);
> + if (ret == -EAGAIN)
> + msleep(1);
> + } while (ret == -EAGAIN && ktime_compare(timeout, ktime_get_raw()) > 0);
this could exit after a single pcode_write() that polled for 1ms, and
msleep(1); is not needed in the last iteration. Retrying 3 times as
discussed earlier would solve that.
> +
> + /* Spec states that TC cold exit can take up to 1ms to complete */
> + if (!ret)
> + msleep(1);
> +
> + drm_dbg_kms(&i915->drm, "TC cold block %s\n", ret ? "failed" :
> + "succeeded");
You missed turning this to an error.
> +}
> +
> static void
> icl_tc_phy_aux_power_well_enable(struct drm_i915_private *dev_priv,
> struct i915_power_well *power_well)
> @@ -593,7 +614,8 @@ icl_tc_phy_aux_power_well_enable(struct drm_i915_private *dev_priv,
>
> hsw_power_well_enable_prepare(dev_priv, power_well);
>
> - /* TODO ICL TC cold handling */
> + if (INTEL_GEN(dev_priv) == 11 && dig_port->tc_legacy_port)
> + icl_tc_cold_exit(dev_priv);
>
> hsw_power_well_enable_complete(dev_priv, power_well);
>
> diff --git a/drivers/gpu/drm/i915/display/intel_tc.c b/drivers/gpu/drm/i915/display/intel_tc.c
> index 9b850c11aa78..74061bf9b2b9 100644
> --- a/drivers/gpu/drm/i915/display/intel_tc.c
> +++ b/drivers/gpu/drm/i915/display/intel_tc.c
> @@ -34,6 +34,7 @@ tc_port_load_fia_params(struct drm_i915_private *i915,
> if (INTEL_INFO(i915)->display.has_modular_fia) {
> modular_fia = intel_uncore_read(&i915->uncore,
> PORT_TX_DFLEXDPSP(FIA1));
> + drm_WARN_ON(&i915->drm, modular_fia == 0xffffffff);
> modular_fia &= MODULAR_FIA_MASK;
> } else {
> modular_fia = 0;
> @@ -52,6 +53,37 @@ tc_port_load_fia_params(struct drm_i915_private *i915,
> }
> }
>
> +static intel_wakeref_t
> +tc_cold_block(struct intel_digital_port *dig_port)
> +{
> + struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
> + enum intel_display_power_domain domain;
> +
> + if (INTEL_GEN(i915) != 11 || !dig_port->tc_legacy_port)
> + return 0;
> +
> + domain = intel_legacy_aux_to_power_domain(dig_port->aux_ch);
> + return intel_display_power_get(i915, domain);
> +}
> +
> +static void
> +tc_cold_unblock(struct intel_digital_port *dig_port, 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
> + * power should still be put down and 0 is a invalid save_depot_stack
> + * id so can be used to skip it for non TC legacy ports.
> + */
> + if (wakeref == 0)
> + return;
> +
> + domain = intel_legacy_aux_to_power_domain(dig_port->aux_ch);
> + intel_display_power_put_async(i915, domain, wakeref);
> +}
> +
> u32 intel_tc_port_get_lane_mask(struct intel_digital_port *dig_port)
> {
> struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
> @@ -415,9 +447,14 @@ static void intel_tc_port_reset_mode(struct intel_digital_port *dig_port,
> enum tc_port_mode old_tc_mode = dig_port->tc_mode;
>
> intel_display_power_flush_work(i915);
> - drm_WARN_ON(&i915->drm,
> - intel_display_power_is_enabled(i915,
> - intel_aux_power_domain(dig_port)));
> + if (INTEL_GEN(i915) != 11 || !dig_port->tc_legacy_port) {
> + enum intel_display_power_domain aux_domain;
> + bool aux_powered;
> +
> + aux_domain = intel_aux_power_domain(dig_port);
> + aux_powered = intel_display_power_is_enabled(i915, aux_domain);
> + drm_WARN_ON(&i915->drm, aux_powered);
> + }
>
> icl_tc_phy_disconnect(dig_port);
> icl_tc_phy_connect(dig_port, required_lanes);
> @@ -439,9 +476,11 @@ intel_tc_port_link_init_refcount(struct intel_digital_port *dig_port,
> void intel_tc_port_sanitize(struct intel_digital_port *dig_port)
> {
> struct intel_encoder *encoder = &dig_port->base;
> + intel_wakeref_t tc_cold_wref;
> int active_links = 0;
>
> mutex_lock(&dig_port->tc_lock);
> + tc_cold_wref = tc_cold_block(dig_port);
>
> dig_port->tc_mode = intel_tc_port_get_current_mode(dig_port);
> if (dig_port->dp.is_mst)
> @@ -466,6 +505,7 @@ void intel_tc_port_sanitize(struct intel_digital_port *dig_port)
> dig_port->tc_port_name,
> tc_port_mode_name(dig_port->tc_mode));
>
> + tc_cold_unblock(dig_port, tc_cold_wref);
> mutex_unlock(&dig_port->tc_lock);
> }
>
> @@ -487,10 +527,15 @@ static bool intel_tc_port_needs_reset(struct intel_digital_port *dig_port)
> bool intel_tc_port_connected(struct intel_digital_port *dig_port)
> {
> bool is_connected;
> + intel_wakeref_t tc_cold_wref;
>
> intel_tc_port_lock(dig_port);
> + tc_cold_wref = tc_cold_block(dig_port);
> +
> is_connected = tc_port_live_status_mask(dig_port) &
> BIT(dig_port->tc_mode);
> +
> + tc_cold_unblock(dig_port, tc_cold_wref);
> intel_tc_port_unlock(dig_port);
>
> return is_connected;
> @@ -506,9 +551,16 @@ static void __intel_tc_port_lock(struct intel_digital_port *dig_port,
>
> mutex_lock(&dig_port->tc_lock);
>
> - if (!dig_port->tc_link_refcount &&
> - intel_tc_port_needs_reset(dig_port))
> - intel_tc_port_reset_mode(dig_port, required_lanes);
> + if (!dig_port->tc_link_refcount) {
> + intel_wakeref_t tc_cold_wref;
> +
> + tc_cold_wref = tc_cold_block(dig_port);
> +
> + if (intel_tc_port_needs_reset(dig_port))
> + intel_tc_port_reset_mode(dig_port, required_lanes);
> +
> + tc_cold_unblock(dig_port, tc_cold_wref);
> + }
>
> drm_WARN_ON(&i915->drm, dig_port->tc_lock_wakeref);
> dig_port->tc_lock_wakeref = wakeref;
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index 1a7bd6db164b..0389afa2361f 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -9108,6 +9108,7 @@ enum {
> #define ICL_PCODE_MEM_SS_READ_QGV_POINT_INFO(point) (((point) << 16) | (0x1 << 8))
> #define GEN6_PCODE_READ_D_COMP 0x10
> #define GEN6_PCODE_WRITE_D_COMP 0x11
> +#define ICL_PCODE_EXIT_TCCOLD 0x12
> #define HSW_PCODE_DE_WRITE_FREQ_REQ 0x17
> #define DISPLAY_IPS_CONTROL 0x19
> /* See also IPS_CTL */
> --
> 2.26.0
>
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