On Mon, Feb 24, 2025 at 11:47:15AM +0530, Ankit Nautiyal wrote:
> For fixed refresh rate use fixed timings for all platforms that support
> VRR. For this add checks to avoid computing and reading VRR for
> platforms that do not support VRR.
> For platforms that do support VRR, readback vrr timings whether or not
> VRR_CTL_FLIP_LINE_EN is set in VRR_CTL or not.
>
> Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@xxxxxxxxx>
> ---
> drivers/gpu/drm/i915/display/intel_vrr.c | 43 ++++++++++++------------
> 1 file changed, 22 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_vrr.c b/drivers/gpu/drm/i915/display/intel_vrr.c
> index 551dcc16f0d4..975fed9930c1 100644
> --- a/drivers/gpu/drm/i915/display/intel_vrr.c
> +++ b/drivers/gpu/drm/i915/display/intel_vrr.c
> @@ -344,6 +344,9 @@ intel_vrr_compute_config(struct intel_crtc_state *crtc_state,
> struct drm_display_mode *adjusted_mode = &crtc_state->hw.adjusted_mode;
> int vmin = 0, vmax = 0;
>
> + if (!HAS_VRR(display))
> + return;
> +
> if (adjusted_mode->flags & DRM_MODE_FLAG_INTERLACE)
> return;
>
> @@ -358,9 +361,6 @@ intel_vrr_compute_config(struct intel_crtc_state *crtc_state,
>
> vmin = intel_vrr_compute_vmin(crtc_state);
>
> - if (vmin >= vmax)
> - return;
> -
> crtc_state->vrr.vmin = vmin;
> crtc_state->vrr.vmax = vmax;
I think your earlier pathc left vmax==0 here for the !in_range so
this looks a bit wrong. But if you change the earlier patch like I
suggested to set vmax=vmin then this would be fine.
>
> @@ -373,7 +373,7 @@ intel_vrr_compute_config(struct intel_crtc_state *crtc_state,
> */
> crtc_state->vrr.vmin -= intel_vrr_flipline_offset(display);
>
> - if (crtc_state->uapi.vrr_enabled)
> + if (crtc_state->uapi.vrr_enabled && vmin < vmax)
> intel_vrr_compute_vrr_timings(crtc_state);
> else if (is_cmrr_frac_required(crtc_state) && is_edp)
> intel_vrr_compute_cmrr_timings(crtc_state);
> @@ -640,6 +640,9 @@ void intel_vrr_get_config(struct intel_crtc_state *crtc_state)
> enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
> u32 trans_vrr_ctl, trans_vrr_vsync;
>
> + if (!HAS_VRR(display))
> + return;
I think the caller is already checking that. But I suppose we could
move the checks into the VRR code.
> +
> trans_vrr_ctl = intel_de_read(display,
> TRANS_VRR_CTL(display, cpu_transcoder));
>
> @@ -663,23 +666,21 @@ void intel_vrr_get_config(struct intel_crtc_state *crtc_state)
> crtc_state->vrr.pipeline_full =
> REG_FIELD_GET(VRR_CTL_PIPELINE_FULL_MASK, trans_vrr_ctl);
>
> - if (trans_vrr_ctl & VRR_CTL_FLIP_LINE_EN) {
> - crtc_state->vrr.flipline = intel_de_read(display,
> - TRANS_VRR_FLIPLINE(display, cpu_transcoder)) + 1;
> - crtc_state->vrr.vmax = intel_de_read(display,
> - TRANS_VRR_VMAX(display, cpu_transcoder)) + 1;
> - crtc_state->vrr.vmin = intel_de_read(display,
> - TRANS_VRR_VMIN(display, cpu_transcoder)) + 1;
> -
> - if (HAS_AS_SDP(display)) {
> - trans_vrr_vsync =
> - intel_de_read(display,
> - TRANS_VRR_VSYNC(display, cpu_transcoder));
> - crtc_state->vrr.vsync_start =
> - REG_FIELD_GET(VRR_VSYNC_START_MASK, trans_vrr_vsync);
> - crtc_state->vrr.vsync_end =
> - REG_FIELD_GET(VRR_VSYNC_END_MASK, trans_vrr_vsync);
> - }
I think you want to keep the VRR_CTL_FLIP_LINE_EN check around the
TRANS_VRR_FLIPLINE read at least, because we want the state checker
to catch any misprogrammng of VRR_CTL_FLIP_LINE_EN.
> + crtc_state->vrr.flipline = intel_de_read(display,
> + TRANS_VRR_FLIPLINE(display, cpu_transcoder)) + 1;
> + crtc_state->vrr.vmax = intel_de_read(display,
> + TRANS_VRR_VMAX(display, cpu_transcoder)) + 1;
> + crtc_state->vrr.vmin = intel_de_read(display,
> + TRANS_VRR_VMIN(display, cpu_transcoder)) + 1;
> +
> + if (HAS_AS_SDP(display)) {
> + trans_vrr_vsync =
> + intel_de_read(display,
> + TRANS_VRR_VSYNC(display, cpu_transcoder));
> + crtc_state->vrr.vsync_start =
> + REG_FIELD_GET(VRR_VSYNC_START_MASK, trans_vrr_vsync);
> + crtc_state->vrr.vsync_end =
> + REG_FIELD_GET(VRR_VSYNC_END_MASK, trans_vrr_vsync);
> }
>
> crtc_state->vrr.enable = trans_vrr_ctl & VRR_CTL_VRR_ENABLE &&
> --
> 2.45.2
--
Ville Syrjälä
Intel
