On 9/12/2025 7:29 PM, Ville Syrjala wrote:
From: Ville Syrjälä <[email protected]> DRRS has been defeatured on LNL+. Adjust HAS_DOUBLE_BUFFERED_M_N() to match. Note that the M/N registers still appear to be double buffered under the hood but the double buffer update point is now documented to be just the last register write to the M/N registers, so it no longer happens synchronously with the vblank/MSA transmission. We should perhaps rename HAS_DOUBLE_BUFFERED_M_N() to more accurately reflect reality, but couldn't come up with a decent name right now...
I think the name is alright for now, we might need to change few corresponding helpers too, if we change the naming here.
Thanks for clearing this up with the HW team and get the bspec updated too. This saves a lot of trouble in the series for making VRR guardband static. Reviewed-by: Ankit Nautiyal <[email protected]> Regards, Ankit
Bspec: 68917 HSD: 14016007525 Cc: Ankit Nautiyal <[email protected]> Signed-off-by: Ville Syrjälä <[email protected]> --- drivers/gpu/drm/i915/display/intel_display_device.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/display/intel_display_device.h b/drivers/gpu/drm/i915/display/intel_display_device.h index f329f1beafef..1f091fbcd0ec 100644 --- a/drivers/gpu/drm/i915/display/intel_display_device.h +++ b/drivers/gpu/drm/i915/display/intel_display_device.h @@ -155,7 +155,7 @@ struct intel_display_platforms { #define HAS_DISPLAY(__display) (DISPLAY_RUNTIME_INFO(__display)->pipe_mask != 0) #define HAS_DMC(__display) (DISPLAY_RUNTIME_INFO(__display)->has_dmc) #define HAS_DMC_WAKELOCK(__display) (DISPLAY_VER(__display) >= 20) -#define HAS_DOUBLE_BUFFERED_M_N(__display) (DISPLAY_VER(__display) >= 9 || (__display)->platform.broadwell) +#define HAS_DOUBLE_BUFFERED_M_N(__display) (IS_DISPLAY_VER((__display), 9, 14) || (__display)->platform.broadwell) #define HAS_DOUBLE_BUFFERED_LUT(__display) (DISPLAY_VER(__display) >= 30) #define HAS_DOUBLE_WIDE(__display) (DISPLAY_VER(__display) < 4) #define HAS_DP20(__display) ((__display)->platform.dg2 || DISPLAY_VER(__display) >= 14)
