diff mbox series

[3/3] drm/i915/dsb: Always set DSB_SKIP_WAITS_EN

Message ID 20240306040806.21697-4-ville.syrjala@linux.intel.com (mailing list archive)
State New, archived
Headers show
Series drm/i915: Fix DSB vblank waits with VRR | expand

Commit Message

Ville Syrjälä March 6, 2024, 4:08 a.m. UTC 
From: Ville Syrjälä <ville.syrjala@linux.intel.com>

Bspec asks us to always set the DSB_SKIP_WAITS_EN bit in
DSB_CHICKEN. This seems to instruct DSB to skip vblank and
scanline waits when PSR is entered.

I don't think we have any cases currently where we would want
to enter PSR while DSB is waiting for something, but let's
set the bit anyway to align with Bspec's wishes.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
---
 drivers/gpu/drm/i915/display/intel_dsb.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

Comments

Animesh Manna March 6, 2024, 12:29 p.m. UTC | #1 
> -----Original Message-----
> From: Intel-gfx <intel-gfx-bounces@lists.freedesktop.org> On Behalf Of Ville
> Syrjala
> Sent: Wednesday, March 6, 2024 9:38 AM
> To: intel-gfx@lists.freedesktop.org
> Subject: [PATCH 3/3] drm/i915/dsb: Always set DSB_SKIP_WAITS_EN
> 
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
> 
> Bspec asks us to always set the DSB_SKIP_WAITS_EN bit in DSB_CHICKEN.
> This seems to instruct DSB to skip vblank and scanline waits when PSR is
> entered.
> 
> I don't think we have any cases currently where we would want to enter PSR
> while DSB is waiting for something, but let's set the bit anyway to align with
> Bspec's wishes.
> 
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

Reviewed-by: Animesh Manna <animesh.manna@intel.com>

> ---
>  drivers/gpu/drm/i915/display/intel_dsb.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_dsb.c
> b/drivers/gpu/drm/i915/display/intel_dsb.c
> index e4515bf92038..4baaa92ceaec 100644
> --- a/drivers/gpu/drm/i915/display/intel_dsb.c
> +++ b/drivers/gpu/drm/i915/display/intel_dsb.c
> @@ -343,12 +343,13 @@ static int intel_dsb_dewake_scanline(const struct
> intel_crtc_state *crtc_state)  static u32 dsb_chicken(struct intel_crtc *crtc)  {
>  	if (crtc->mode_flags & I915_MODE_FLAG_VRR)
> -		return DSB_CTRL_WAIT_SAFE_WINDOW |
> +		return DSB_SKIP_WAITS_EN |
> +			DSB_CTRL_WAIT_SAFE_WINDOW |
>  			DSB_CTRL_NO_WAIT_VBLANK |
>  			DSB_INST_WAIT_SAFE_WINDOW |
>  			DSB_INST_NO_WAIT_VBLANK;
>  	else
> -		return 0;
> +		return DSB_SKIP_WAITS_EN;
>  }
> 
>  static void _intel_dsb_commit(struct intel_dsb *dsb, u32 ctrl,
> --
> 2.43.0
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/display/intel_dsb.c b/drivers/gpu/drm/i915/display/intel_dsb.c
index e4515bf92038..4baaa92ceaec 100644
--- a/drivers/gpu/drm/i915/display/intel_dsb.c
+++ b/drivers/gpu/drm/i915/display/intel_dsb.c
@@ -343,12 +343,13 @@  static int intel_dsb_dewake_scanline(const struct intel_crtc_state *crtc_state)
 static u32 dsb_chicken(struct intel_crtc *crtc)
 {
 	if (crtc->mode_flags & I915_MODE_FLAG_VRR)
-		return DSB_CTRL_WAIT_SAFE_WINDOW |
+		return DSB_SKIP_WAITS_EN |
+			DSB_CTRL_WAIT_SAFE_WINDOW |
 			DSB_CTRL_NO_WAIT_VBLANK |
 			DSB_INST_WAIT_SAFE_WINDOW |
 			DSB_INST_NO_WAIT_VBLANK;
 	else
-		return 0;
+		return DSB_SKIP_WAITS_EN;
 }
 
 static void _intel_dsb_commit(struct intel_dsb *dsb, u32 ctrl,