Re: [PATCH v5 7/9] drm/i915/tgl: DC3CO PSR2 helper

Imre Deak
2019-08-13T16:06:29Z

On Sat, Aug 10, 2019 at 12:02:21AM +0530, Anshuman Gupta wrote:
> Add dc3co helper functions to enable/disable psr2 deep sleep.
> Disallow DC3CO state before PSR2 exit, it essentially does
> that by putting a reference to POWER_DOMAIN_VIDEO before
> PSR2 exit.
>
> Cc: Jani Nikula <jani.nikula@intel.com>
> Cc: Imre Deak <imre.deak@intel.com>
> Cc: Animesh Manna <animesh.manna@intel.com>
> Cc: José Roberto de Souza <jose.souza@intel.com>
> Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
> ---
> drivers/gpu/drm/i915/display/intel_psr.c | 44 ++++++++++++++++++++++++
> drivers/gpu/drm/i915/display/intel_psr.h | 2 ++
> 2 files changed, 46 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c
> index ad7044ea1efe..42f27df8445d 100644
> --- a/drivers/gpu/drm/i915/display/intel_psr.c
> +++ b/drivers/gpu/drm/i915/display/intel_psr.c
> @@ -533,6 +533,49 @@ static void hsw_activate_psr2(struct intel_dp *intel_dp)
> I915_WRITE(EDP_PSR2_CTL, val);
> }
>
> +void tgl_psr2_deep_sleep_disable(struct drm_i915_private *dev_priv)
> +{
> + u32 val;
> + int idle_frames = 0;
> +
> + idle_frames <<= EDP_PSR2_IDLE_FRAME_SHIFT;
> + val = I915_READ(EDP_PSR2_CTL);
> + val &= ~EDP_PSR2_IDLE_FRAME_MASK;
> + val |= idle_frames;
> + I915_WRITE(EDP_PSR2_CTL, val);

This could be factored out to a helper and reused elsewhere.

> +}
> +
> +void tgl_psr2_deep_sleep_enable(struct drm_i915_private *dev_priv)
> +{
> + u32 val;
> + int idle_frames;
> +
> + /*
> + * Let's use 6 as the minimum to cover all known cases including the
> + * off-by-one issue that HW has in some cases.
> + */
> + idle_frames = max(6, dev_priv->vbt.psr.idle_frames);
> + idle_frames = max(idle_frames, dev_priv->psr.sink_sync_latency + 1);
> + idle_frames <<= EDP_PSR2_IDLE_FRAME_SHIFT;
> + val = I915_READ(EDP_PSR2_CTL);
> + val &= ~EDP_PSR2_IDLE_FRAME_MASK;
> + val |= idle_frames;
> + I915_WRITE(EDP_PSR2_CTL, val);
> +}
> +
> +static void tgl_disallow_dc3co_on_psr2_exit(struct drm_i915_private *dev_priv)
> +{
> + intel_wakeref_t wakeref __maybe_unused;
> +
> + /* Before PSR2 exit disallow dc3co*/
> + mutex_lock(&dev_priv->csr.dc5_mutex);
> + wakeref = fetch_and_zero(&dev_priv->csr.dc5_wakeref);
> + if (wakeref)
> + intel_display_power_put(dev_priv, POWER_DOMAIN_VIDEO,
> + dev_priv->csr.dc5_wakeref);
> + mutex_unlock(&dev_priv->csr.dc5_mutex);
> +}
> +
> static bool intel_psr2_config_valid(struct intel_dp *intel_dp,
> struct intel_crtc_state *crtc_state)
> {
> @@ -789,6 +832,7 @@ static void intel_psr_exit(struct drm_i915_private *dev_priv)
> }
>
> if (dev_priv->psr.psr2_enabled) {
> + tgl_disallow_dc3co_on_psr2_exit(dev_priv);
> val = I915_READ(EDP_PSR2_CTL);
> WARN_ON(!(val & EDP_PSR2_ENABLE));
> I915_WRITE(EDP_PSR2_CTL, val & ~EDP_PSR2_ENABLE);
> diff --git a/drivers/gpu/drm/i915/display/intel_psr.h b/drivers/gpu/drm/i915/display/intel_psr.h
> index dc818826f36d..6fb4c385489c 100644
> --- a/drivers/gpu/drm/i915/display/intel_psr.h
> +++ b/drivers/gpu/drm/i915/display/intel_psr.h
> @@ -36,5 +36,7 @@ void intel_psr_short_pulse(struct intel_dp *intel_dp);
> int intel_psr_wait_for_idle(const struct intel_crtc_state *new_crtc_state,
> u32 *out_value);
> bool intel_psr_enabled(struct intel_dp *intel_dp);
> +void tgl_psr2_deep_sleep_disable(struct drm_i915_private *dev_priv);
> +void tgl_psr2_deep_sleep_enable(struct drm_i915_private *dev_priv);
>
> #endif /* __INTEL_PSR_H__ */
> --
> 2.21.0
>