summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorMitul Golani <mitulkumar.ajitkumar.golani@intel.com>2026-09-17 13:13:22 +0530
committerJani Nikula <jani.nikula@intel.com>2026-09-28 12:14:43 +0300
commitc034e8a46e4cb703018fe7e10fe5a3a974d6a7c3 (patch)
treec01b0f16226520841c21691c46d2f0b0b91a00c7
parent72d3fcf802c45d00b300f25b848a93c3a2bd7c7e (diff)
downloadlinux-stable-c034e8a46e4cb703018fe7e10fe5a3a974d6a7c3.tar.gz
linux-stable-c034e8a46e4cb703018fe7e10fe5a3a974d6a7c3.zip
drm/i915/vrr: Disable DC balance by default
Disable VRR DC balance by default due to timing issues observed on some panel/TCON combinations. Keep the module parameter to enable DC balance during debugging and to isolate DC balance effects from underlying VRR/display timing issues. --v2: - Make enable_dc_balance a bool and keep it disabled by default; fix the parameter type/value mismatch and correct the description (Chaitanya Kumar Borah, Jani Nikula) - Explain in the commit message why the feature is gated and why a module parameter is used (Jani Nikula) --v3: - Commit message update (Jani Nikula) Fixes: 555819270707 ("drm/i915/vrr: Enable DC Balance") Cc: <stable@vger.kernel.org> # v7.0+ Signed-off-by: Mitul Golani <mitulkumar.ajitkumar.golani@intel.com> Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com> Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com> Link: https://patch.msgid.link/20260917074322.2606738-1-mitulkumar.ajitkumar.golani@intel.com (cherry picked from commit d1ef78f0581e856c4238c751e9ae2884ce58c275) Signed-off-by: Jani Nikula <jani.nikula@intel.com>
-rw-r--r--drivers/gpu/drm/i915/display/intel_display_params.c4
-rw-r--r--drivers/gpu/drm/i915/display/intel_display_params.h1
-rw-r--r--drivers/gpu/drm/i915/display/intel_vrr.c4
3 files changed, 8 insertions, 1 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_display_params.c b/drivers/gpu/drm/i915/display/intel_display_params.c
index 2aed110c5..ca0ef466b 100644
--- a/drivers/gpu/drm/i915/display/intel_display_params.c
+++ b/drivers/gpu/drm/i915/display/intel_display_params.c
@@ -120,6 +120,10 @@ intel_display_param_named_unsafe(enable_psr, int, 0400,
"(0=disabled, 1=enable up to PSR1, 2=enable up to PSR2) "
"Default: -1 (use per-chip default)");
+intel_display_param_named_unsafe(enable_dc_balance, bool, 0400,
+ "Enable VRR DC balance (0=disabled, 1=enabled). "
+ "Default: 0 (disabled)");
+
intel_display_param_named_unsafe(enable_panel_replay, int, 0400,
"Enable Panel Replay (0=disabled, 1=enabled). Default: -1 (use per-chip default)");
diff --git a/drivers/gpu/drm/i915/display/intel_display_params.h b/drivers/gpu/drm/i915/display/intel_display_params.h
index b95ecf728..16759e94c 100644
--- a/drivers/gpu/drm/i915/display/intel_display_params.h
+++ b/drivers/gpu/drm/i915/display/intel_display_params.h
@@ -46,6 +46,7 @@ struct drm_printer;
param(bool, enable_dp_mst, true, 0600) \
param(int, enable_fbc, -1, 0600) \
param(int, enable_psr, -1, 0600) \
+ param(bool, enable_dc_balance, false, 0600) \
param(int, enable_panel_replay, -1, 0600) \
param(bool, psr_safest_params, false, 0400) \
param(bool, enable_psr2_sel_fetch, true, 0400) \
diff --git a/drivers/gpu/drm/i915/display/intel_vrr.c b/drivers/gpu/drm/i915/display/intel_vrr.c
index 51e4f3309..cfc0cfbff 100644
--- a/drivers/gpu/drm/i915/display/intel_vrr.c
+++ b/drivers/gpu/drm/i915/display/intel_vrr.c
@@ -386,10 +386,12 @@ static bool intel_vrr_dc_balance_possible(const struct intel_crtc_state *crtc_st
static void
intel_vrr_dc_balance_compute_config(struct intel_crtc_state *crtc_state)
{
+ struct intel_display *display = to_intel_display(crtc_state);
int guardband_usec, adjustment_usec;
struct drm_display_mode *adjusted_mode = &crtc_state->hw.adjusted_mode;
- if (!intel_vrr_dc_balance_possible(crtc_state) || !crtc_state->vrr.enable)
+ if (!intel_vrr_dc_balance_possible(crtc_state) ||
+ !crtc_state->vrr.enable || !display->params.enable_dc_balance)
return;
crtc_state->vrr.dc_balance.vmax = crtc_state->vrr.vmax;