On 6/16/2026 10:43 AM, Manna, Animesh wrote:

-----Original Message-----
From: Nautiyal, Ankit K <[email protected]>
Sent: Friday, June 12, 2026 9:18 AM
To: [email protected]; [email protected]
Cc: Hogander, Jouni <[email protected]>; Manna, Animesh
<[email protected]>; Nautiyal, Ankit K
<[email protected]>
Subject: [PATCH] drm/i915/alpm: Move the check for PSR and Fixed RR in
compute_config_late

With optimized guardband, we need to take into account LOBF requirements
via intel_alpm_lobf_min_guardband().

Currently, we set has_lobf based not only on whether it is supported, but
also on whether PSR/fixed RR are ON. Since these features can switch ON and
OFF seamlessly, this may cause LOBF to change, resulting in a change in
guardband requirements, and eventually to a full modeset.

To avoid this, always account for LOBF if it is supported, in the
encoder->compute_config() stage. For this, allow has_lobf to be set
irrespective of PSR/Fixed RR. Later, in the encoder->compute_config_late()
stage, use the PSR/Fixed RR checks to set has_lobf to the final value.

Move the PSR/Fixed RR checks from intel_alpm_lobf_compute_config() to
intel_alpm_lobf_compute_config_late(), where we already account for other
LOBF constraints.

Signed-off-by: Ankit Nautiyal <[email protected]>
---
  drivers/gpu/drm/i915/display/intel_alpm.c | 12 +++++++-----
  1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_alpm.c
b/drivers/gpu/drm/i915/display/intel_alpm.c
index c6963ea420cc..b7cab744d0ea 100644
--- a/drivers/gpu/drm/i915/display/intel_alpm.c
+++ b/drivers/gpu/drm/i915/display/intel_alpm.c
@@ -291,6 +291,12 @@ void intel_alpm_lobf_compute_config_late(struct
intel_dp *intel_dp,
        if (!crtc_state->has_lobf)
                return;

+       if (crtc_state->has_psr)
+               return;
If has_psr is true we need to reset has_lobf otherwise both flags will be true.

+
+       if (!intel_vrr_is_fixed_rr(crtc_state))
+               return;
Same for fixed_rr.

Oh yes you are right. I will correct this and resend.

Thanks,

Ankit

+
        if (!intel_alpm_lobf_is_window1_sufficient(crtc_state)) {
                crtc_state->has_lobf = false;
                return;
@@ -343,11 +349,7 @@ void intel_alpm_lobf_compute_config(struct
intel_dp *intel_dp,
        if (!intel_dp->as_sdp_supported)
                return;

-       if (crtc_state->has_psr)
-               return;
-
-       if (!intel_vrr_always_use_vrr_tg(display) ||
-           !intel_vrr_is_fixed_rr(crtc_state))
+       if (!intel_vrr_always_use_vrr_tg(display))
                return;

        if (!(intel_alpm_aux_wake_supported(intel_dp) ||
--
2.45.2

Reply via email to