> -----Original Message-----
> From: Kandpal, Suraj <[email protected]>
> Sent: Tuesday, April 16, 2024 12:58 PM
> To: [email protected]
> Cc: Borah, Chaitanya Kumar <[email protected]>; Shankar,
> Uma <[email protected]>; Nautiyal, Ankit K
> <[email protected]>; Bhadane, Dnyaneshwar
> <[email protected]>; Kandpal, Suraj
> <[email protected]>
> Subject: [PATCH 2/2] drm/i915/pps: Disable DPLS_GATING around pps
> sequence
>
> Disable bit 29 of SCLKGATE_DIS register around pps sequence when we turn
> panel power on.
> WA: 16023567976
> Bspec: 49304
>
> Signed-off-by: Suraj Kandpal <[email protected]>
> ---
> drivers/gpu/drm/i915/display/intel_pps.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_pps.c
> b/drivers/gpu/drm/i915/display/intel_pps.c
> index 3078dfac7817..a912e712ca63 100644
> --- a/drivers/gpu/drm/i915/display/intel_pps.c
> +++ b/drivers/gpu/drm/i915/display/intel_pps.c
> @@ -919,6 +919,7 @@ void intel_pps_on_unlocked(struct intel_dp
> *intel_dp)
> struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
> u32 pp;
> i915_reg_t pp_ctrl_reg;
> + int dis_ver = DISPLAY_VER(dev_priv);
>
> lockdep_assert_held(&dev_priv->display.pps.mutex);
>
> @@ -948,6 +949,13 @@ void intel_pps_on_unlocked(struct intel_dp
> *intel_dp)
> intel_de_posting_read(dev_priv, pp_ctrl_reg);
> }
>
> + /* WA: 16023567976
> + * Disable DPLS gating around power sequence.
> + */
> + if (dis_ver >= 12 && dis_ver <= 14)
Hi Suraj,
You might want to use IS_DISPLAY_IP_RANGE() as it is fixed IP based range.
Dnyaneshwar
> + intel_de_rmw(dev_priv, SCLKGATE_DIS,
> + DPLS_GATING_DISABLE, 1);
> +
> pp |= PANEL_POWER_ON;
> if (!IS_IRONLAKE(dev_priv))
> pp |= PANEL_POWER_RESET;
> @@ -958,6 +966,10 @@ void intel_pps_on_unlocked(struct intel_dp
> *intel_dp)
> wait_panel_on(intel_dp);
> intel_dp->pps.last_power_on = jiffies;
>
> + if (dis_ver >= 12 && dis_ver <= 14)
> + intel_de_rmw(dev_priv, SCLKGATE_DIS,
> + DPLS_GATING_DISABLE, 0);
> +
> if (IS_IRONLAKE(dev_priv)) {
> pp |= PANEL_POWER_RESET; /* restore panel reset bit */
> intel_de_write(dev_priv, pp_ctrl_reg, pp);
> --
> 2.43.2
