On Thu, 06 Jun 2024, Suraj Kandpal <suraj.kandpal@xxxxxxxxx> wrote:
> To reach PC10 when PKG_C_LATENCY is configure we must do the following
> things
> 1) Enter PSR1 only when delayed_vblank < 6 lines and DC5 can be entered
> 2) Allow PSR2 deep sleep when DC5 can be entered
> 3) DC5 can be entered when all transocoder have either PSR1, PSR2 or
> eDP 1.5 PR ALPM enabled and VBI is disabled and flips and pushes are
> not happening.
>
> WA: 16023497226
> Signed-off-by: Suraj Kandpal <suraj.kandpal@xxxxxxxxx>
> ---
> drivers/gpu/drm/i915/display/intel_psr.c | 75 +++++++++++++++++++++++-
> 1 file changed, 73 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c
> index 6fc88f6c6b26..b22745c019df 100644
> --- a/drivers/gpu/drm/i915/display/intel_psr.c
> +++ b/drivers/gpu/drm/i915/display/intel_psr.c
> @@ -811,12 +811,81 @@ static u8 psr_compute_idle_frames(struct intel_dp *intel_dp)
> return idle_frames;
> }
>
> +static bool intel_psr_check_delayed_vblank_limit(struct drm_i915_private *i915,
> + enum transcoder cpu_transcoder)
> +{
> + return intel_de_read(i915, TRANS_SET_CONTEXT_LATENCY(cpu_transcoder)) >= 6;
Please don't use the hardware to preserve the state for you. It will get
really complicated to maintain.
> +}
> +
> +static bool intel_psr_is_dpkgc_configured(struct drm_i915_private *i915)
> +{
> + return intel_de_read(i915, LNL_PKG_C_LATENCY) == U32_MAX;
Ditto.
> +}
> +
> +static bool intel_psr_is_dc5_entry_possible(struct drm_i915_private *i915)
> +{
> + struct intel_crtc *intel_crtc;
> + bool ret = true;
> +
> + for_each_intel_crtc(&i915->drm, intel_crtc) {
> + struct intel_encoder *encoder;
> + struct drm_crtc *crtc = &intel_crtc->base;
> + enum pipe pipe = intel_crtc->pipe;
> +
> + if (!crtc->active)
> + continue;
> +
> + if (!(i915->display.irq.de_irq_mask[pipe] & GEN8_PIPE_VBLANK))
You have no business looking directly at that. It's for display irq code
*only*.
> + ret = false;
> +
> + for_each_encoder_on_crtc(&i915->drm, crtc, encoder) {
> + struct intel_dp *intel_dp = enc_to_intel_dp(_encoder);
> + struct intel_psr *psr = &intel_dp->psr;
> +
> + if (!psr->enabled)
> + ret = false;
> + }
> + }
> +
> + return ret;
> +}
> +
> +static bool wa_16023497226_check(struct intel_dp *intel_dp, bool psr1)
> +{
> + struct drm_i915_private *i915 = dp_to_i915(intel_dp);
> + enum transcoder cpu_transcoder = intel_dp->psr.transcoder;
> +
> + if (DISPLAY_VER(i915) != 20)
> + return true;
> +
> + if (is_dpkg_c_configured(i915)) {
> + if (psr1 &&
> + (intel_psr_check_delayed_vblank_limit(i915, cpu_transcoder) ||
> + intel_psr_is_dc5_entry_possible(i915)))
> + return true;
> + else if (!psr1 && is_dc5_entry_possible(i915))
> + return true;
> + else
> + return false;
> + }
> +
> + return true;
> +}
> +
> static bool hsw_activate_psr1(struct intel_dp *intel_dp)
> {
> struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
> enum transcoder cpu_transcoder = intel_dp->psr.transcoder;
> u32 max_sleep_time = 0x1f;
> - u32 val = EDP_PSR_ENABLE;
> + u32 val = 0;
> +
> + /* WA: 16023497226*/
> + if (wa_16023497226_check(intel_dp, true)) {
> + val = EDP_PSR_ENABLE;
> + } else {
> + drm_dbg_kms(&dev_priv->drm, "PSR1 was not activated\n");
Please add reason.
> + return false;
> + }
Switch the condition around and use early return.
>
> val |= EDP_PSR_IDLE_FRAMES(psr_compute_idle_frames(intel_dp));
>
> @@ -910,7 +979,9 @@ static void hsw_activate_psr2(struct intel_dp *intel_dp)
> u32 val = EDP_PSR2_ENABLE;
> u32 psr_val = 0;
>
> - val |= EDP_PSR2_IDLE_FRAMES(psr_compute_idle_frames(intel_dp));
> + /* WA: 16023497226*/
> + if (wa_16023497226_check(intel_dp, false))
> + val |= EDP_PSR2_IDLE_FRAMES(psr_compute_idle_frames(intel_dp));
>
> if (DISPLAY_VER(dev_priv) < 14 && !IS_ALDERLAKE_P(dev_priv))
> val |= EDP_SU_TRACK_ENABLE;
--
Jani Nikula, Intel
