diff mbox series

drm/i915/display: Dual refresh rate fastset fixes with VRR fastset

Message ID 20230809232646.1947120-1-navaremanasi@chromium.org (mailing list archive)
State New, archived
Headers show
Series drm/i915/display: Dual refresh rate fastset fixes with VRR fastset | expand

Commit Message

Manasi Navare Aug. 9, 2023, 11:26 p.m. UTC
Dual refresh rate (DRR) fastset seamlessly lets refresh rate
throttle without needing a full modeset.
However with the recent VRR fastset patches that got merged this
logic was broken. This is broken because now with VRR fastset
VRR parameters are calculated by default at the nominal refresh rate say 120Hz.
Now when DRR throttle happens to switch refresh rate to 60Hz, crtc clock
changes and this throws a mismatch in VRR parameters and fastset logic
for DRR gets thrown off and full modeset is indicated.

This patch fixes this by ignoring the pipe mismatch for VRR parameters
in the case of DRR and when VRR is not enabled. With this fix, DRR
will still throttle seamlessly as long as VRR is not enabled.

This will still need a full modeset for both DRR and VRR operating together
during the refresh rate throttle and then enabling VRR since now VRR
parameters need to be recomputed with new crtc clock and written to HW.

This DRR + VRR fastset in conjunction needs more work in the driver and
will be fixed in later patches.

Cc: Drew Davenport <ddavenport@chromium.org>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Manasi Navare <navaremanasi@chromium.org>
---
 drivers/gpu/drm/i915/display/intel_display.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

Comments

Vidya Srinivas Aug. 11, 2023, 5:36 a.m. UTC | #1
Hello Mansi,

I tried your patch for the VRR panel we have (bug https://gitlab.freedesktop.org/drm/intel/-/issues/8851).
Have uploaded logs with your patch to the bug as well.
But display is blanking out and also I get underrun. Could you kindly have a check please? Many thanks.

Regards
Vidya

> -----Original Message-----
> From: Intel-gfx <intel-gfx-bounces@lists.freedesktop.org> On Behalf Of
> Manasi Navare
> Sent: Thursday, August 10, 2023 4:57 AM
> To: intel-gfx@lists.freedesktop.org
> Cc: Drew Davenport <ddavenport@chromium.org>; Sean Paul
> <seanpaul@chromium.org>
> Subject: [Intel-gfx] [PATCH] drm/i915/display: Dual refresh rate fastset fixes
> with VRR fastset
> 
> Dual refresh rate (DRR) fastset seamlessly lets refresh rate throttle without
> needing a full modeset.
> However with the recent VRR fastset patches that got merged this logic was
> broken. This is broken because now with VRR fastset VRR parameters are
> calculated by default at the nominal refresh rate say 120Hz.
> Now when DRR throttle happens to switch refresh rate to 60Hz, crtc clock
> changes and this throws a mismatch in VRR parameters and fastset logic for
> DRR gets thrown off and full modeset is indicated.
> 
> This patch fixes this by ignoring the pipe mismatch for VRR parameters in the
> case of DRR and when VRR is not enabled. With this fix, DRR will still throttle
> seamlessly as long as VRR is not enabled.
> 
> This will still need a full modeset for both DRR and VRR operating together
> during the refresh rate throttle and then enabling VRR since now VRR
> parameters need to be recomputed with new crtc clock and written to HW.
> 
> This DRR + VRR fastset in conjunction needs more work in the driver and will
> be fixed in later patches.
> 
> Cc: Drew Davenport <ddavenport@chromium.org>
> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
> Cc: Sean Paul <seanpaul@chromium.org>
> Signed-off-by: Manasi Navare <navaremanasi@chromium.org>
> ---
>  drivers/gpu/drm/i915/display/intel_display.c | 14 ++++++++------
>  1 file changed, 8 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_display.c
> b/drivers/gpu/drm/i915/display/intel_display.c
> index 763ab569d8f3..441d5f3e06c0 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.c
> +++ b/drivers/gpu/drm/i915/display/intel_display.c
> @@ -5352,7 +5352,7 @@ intel_pipe_config_compare(const struct
> intel_crtc_state *current_config,
>  	if (IS_G4X(dev_priv) || DISPLAY_VER(dev_priv) >= 5)
>  		PIPE_CONF_CHECK_I(pipe_bpp);
> 
> -	if (!fastset || !pipe_config->seamless_m_n) {
> +	if ((!fastset || !pipe_config->seamless_m_n) &&
> +!pipe_config->vrr.enable) {
>  		PIPE_CONF_CHECK_I(hw.pipe_mode.crtc_clock);
>  		PIPE_CONF_CHECK_I(hw.adjusted_mode.crtc_clock);
>  	}
> @@ -5387,11 +5387,13 @@ intel_pipe_config_compare(const struct
> intel_crtc_state *current_config,
> 
>  	if (!fastset)
>  		PIPE_CONF_CHECK_BOOL(vrr.enable);
> -	PIPE_CONF_CHECK_I(vrr.vmin);
> -	PIPE_CONF_CHECK_I(vrr.vmax);
> -	PIPE_CONF_CHECK_I(vrr.flipline);
> -	PIPE_CONF_CHECK_I(vrr.pipeline_full);
> -	PIPE_CONF_CHECK_I(vrr.guardband);
> +	if ((!fastset && !pipe_config->seamless_m_n) || pipe_config-
> >vrr.enable) {
> +		PIPE_CONF_CHECK_I(vrr.vmin);
> +		PIPE_CONF_CHECK_I(vrr.vmax);
> +		PIPE_CONF_CHECK_I(vrr.flipline);
> +		PIPE_CONF_CHECK_I(vrr.pipeline_full);
> +		PIPE_CONF_CHECK_I(vrr.guardband);
> +	}
> 
>  #undef PIPE_CONF_CHECK_X
>  #undef PIPE_CONF_CHECK_I
> --
> 2.41.0.640.ga95def55d0-goog
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index 763ab569d8f3..441d5f3e06c0 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -5352,7 +5352,7 @@  intel_pipe_config_compare(const struct intel_crtc_state *current_config,
 	if (IS_G4X(dev_priv) || DISPLAY_VER(dev_priv) >= 5)
 		PIPE_CONF_CHECK_I(pipe_bpp);
 
-	if (!fastset || !pipe_config->seamless_m_n) {
+	if ((!fastset || !pipe_config->seamless_m_n) && !pipe_config->vrr.enable) {
 		PIPE_CONF_CHECK_I(hw.pipe_mode.crtc_clock);
 		PIPE_CONF_CHECK_I(hw.adjusted_mode.crtc_clock);
 	}
@@ -5387,11 +5387,13 @@  intel_pipe_config_compare(const struct intel_crtc_state *current_config,
 
 	if (!fastset)
 		PIPE_CONF_CHECK_BOOL(vrr.enable);
-	PIPE_CONF_CHECK_I(vrr.vmin);
-	PIPE_CONF_CHECK_I(vrr.vmax);
-	PIPE_CONF_CHECK_I(vrr.flipline);
-	PIPE_CONF_CHECK_I(vrr.pipeline_full);
-	PIPE_CONF_CHECK_I(vrr.guardband);
+	if ((!fastset && !pipe_config->seamless_m_n) || pipe_config->vrr.enable) {
+		PIPE_CONF_CHECK_I(vrr.vmin);
+		PIPE_CONF_CHECK_I(vrr.vmax);
+		PIPE_CONF_CHECK_I(vrr.flipline);
+		PIPE_CONF_CHECK_I(vrr.pipeline_full);
+		PIPE_CONF_CHECK_I(vrr.guardband);
+	}
 
 #undef PIPE_CONF_CHECK_X
 #undef PIPE_CONF_CHECK_I