[Intel-gfx] [PATCH 1/2] drm/i915/psr: Equation changed for sending start/stop on prior line

[Kahola, Mika]

> -----Original Message-----
> From: Hogander, Jouni <jouni.hogander at intel.com>
> Sent: Monday, September 5, 2022 1:24 PM
> To: intel-gfx at lists.freedesktop.org
> Cc: Hogander, Jouni <jouni.hogander at intel.com>; Kahola, Mika
> <mika.kahola at intel.com>; Souza, Jose <jose.souza at intel.com>
> Subject: [PATCH 1/2] drm/i915/psr: Equation changed for sending start/stop on
> prior line
> 
> Equation for sending start/end SDP prior to the SU region start/end has
> changed. Update used formula.
> 
> Bspec: 49274
> 
> Cc: Mika Kahola <mika.kahola at intel.com>
> Cc: José Roberto de Souza <jose.souza at intel.com>

Reviewed-by: Mika Kahola <mika.kahola at intel.com>

> Signed-off-by: Jouni Högander <jouni.hogander at intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_psr.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_psr.c
> b/drivers/gpu/drm/i915/display/intel_psr.c
> index 079b7d3d0c53..6f03bf16d6f4 100644
> --- a/drivers/gpu/drm/i915/display/intel_psr.c
> +++ b/drivers/gpu/drm/i915/display/intel_psr.c
> @@ -805,8 +805,8 @@ static bool
> _compute_psr2_sdp_prior_scanline_indication(struct intel_dp *intel_d
>  	hblank_total = adjusted_mode->crtc_hblank_end - adjusted_mode-
> >crtc_hblank_start;
>  	hblank_ns = div_u64(1000000ULL * hblank_total, adjusted_mode-
> >crtc_clock);
> 
> -	/* From spec: (72 / number of lanes) * 1000 / symbol clock frequency
> MHz */
> -	req_ns = (72 / crtc_state->lane_count) * 1000 / (crtc_state->port_clock
> / 1000);
> +	/* From spec: ((60 / number of lanes) + 11) * 1000 / symbol clock
> frequency MHz */
> +	req_ns = ((60 / crtc_state->lane_count) + 11) * 1000 /
> +(crtc_state->port_clock / 1000);
> 
>  	if ((hblank_ns - req_ns) > 100)
>  		return true;
> --
> 2.34.1