[PATCH 2/2] drm/i915: disable fbc due to Wa_16023588340

[Cavitt, Jonathan]

-----Original Message-----
From: Auld, Matthew <matthew.auld at intel.com> 
Sent: Wednesday, June 19, 2024 7:31 AM
To: intel-xe at lists.freedesktop.org
Cc: Cavitt, Jonathan <jonathan.cavitt at intel.com>; Roper, Matthew D <matthew.d.roper at intel.com>; De Marchi, Lucas <lucas.demarchi at intel.com>; Govindapillai, Vinod <vinod.govindapillai at intel.com>; intel-gfx at lists.freedesktop.org
Subject: [PATCH 2/2] drm/i915: disable fbc due to Wa_16023588340
> 
> On BMG-G21 we need to disable fbc due to complications around the WA.
> 
> Signed-off-by: Matthew Auld <matthew.auld at intel.com>
> Cc: Jonathan Cavitt <jonathan.cavitt at intel.com>
> Cc: Matt Roper <matthew.d.roper at intel.com>
> Cc: Lucas De Marchi <lucas.demarchi at intel.com>
> Cc: Vinod Govindapillai <vinod.govindapillai at intel.com>
> Cc: intel-gfx at lists.freedesktop.org
> ---
>  drivers/gpu/drm/i915/display/intel_display_wa.h |  8 ++++++++
>  drivers/gpu/drm/i915/display/intel_fbc.c        |  6 ++++++
>  drivers/gpu/drm/xe/Makefile                     |  4 +++-
>  drivers/gpu/drm/xe/display/xe_display_wa.c      | 16 ++++++++++++++++
>  4 files changed, 33 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/gpu/drm/xe/display/xe_display_wa.c
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_display_wa.h b/drivers/gpu/drm/i915/display/intel_display_wa.h
> index 63201d09852c..be644ab6ae00 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_wa.h
> +++ b/drivers/gpu/drm/i915/display/intel_display_wa.h
> @@ -6,8 +6,16 @@
>  #ifndef __INTEL_DISPLAY_WA_H__
>  #define __INTEL_DISPLAY_WA_H__
>  
> +#include <linux/types.h>
> +
>  struct drm_i915_private;
>  
>  void intel_display_wa_apply(struct drm_i915_private *i915);
>  
> +#ifdef I915
> +static inline bool intel_display_needs_wa_16023588340(struct drm_i915_private *i915) { return false; }
> +#else
> +bool intel_display_needs_wa_16023588340(struct drm_i915_private *i915);
> +#endif
> +
>  #endif
> diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i915/display/intel_fbc.c
> index 67116c9f1464..8488f82143a4 100644
> --- a/drivers/gpu/drm/i915/display/intel_fbc.c
> +++ b/drivers/gpu/drm/i915/display/intel_fbc.c
> @@ -56,6 +56,7 @@
>  #include "intel_display_device.h"
>  #include "intel_display_trace.h"
>  #include "intel_display_types.h"
> +#include "intel_display_wa.h"
>  #include "intel_fbc.h"
>  #include "intel_fbc_regs.h"
>  #include "intel_frontbuffer.h"
> @@ -1237,6 +1238,11 @@ static int intel_fbc_check_plane(struct intel_atomic_state *state,
>  		return 0;
>  	}
>  
> +	if (intel_display_needs_wa_16023588340(i915)) {
> +		plane_state->no_fbc_reason = "Wa_16023588340";
> +		return 0;
> +	}
> +
>  	/* WaFbcTurnOffFbcWhenHyperVisorIsUsed:skl,bxt */
>  	if (i915_vtd_active(i915) && (IS_SKYLAKE(i915) || IS_BROXTON(i915))) {
>  		plane_state->no_fbc_reason = "VT-d enabled";
> diff --git a/drivers/gpu/drm/xe/Makefile b/drivers/gpu/drm/xe/Makefile
> index 0e16e5029081..f7521fd5db4c 100644
> --- a/drivers/gpu/drm/xe/Makefile
> +++ b/drivers/gpu/drm/xe/Makefile
> @@ -34,7 +34,8 @@ uses_generated_oob := \
>  	$(obj)/xe_ring_ops.o \
>  	$(obj)/xe_vm.o \
>  	$(obj)/xe_wa.o \
> -	$(obj)/xe_ttm_stolen_mgr.o
> +	$(obj)/xe_ttm_stolen_mgr.o \
> +	$(obj)/display/xe_display_wa.o \
>  
>  $(uses_generated_oob): $(generated_oob)
>  
> @@ -192,6 +193,7 @@ xe-$(CONFIG_DRM_XE_DISPLAY) += \
>  	display/xe_display.o \
>  	display/xe_display_misc.o \
>  	display/xe_display_rps.o \
> +	display/xe_display_wa.o \
>  	display/xe_dsb_buffer.o \
>  	display/xe_fb_pin.o \
>  	display/xe_hdcp_gsc.o \
> diff --git a/drivers/gpu/drm/xe/display/xe_display_wa.c b/drivers/gpu/drm/xe/display/xe_display_wa.c
> new file mode 100644
> index 000000000000..68e3d1959ad6
> --- /dev/null
> +++ b/drivers/gpu/drm/xe/display/xe_display_wa.c
> @@ -0,0 +1,16 @@
> +// SPDX-License-Identifier: MIT
> +/*
> + * Copyright © 2024 Intel Corporation
> + */
> +
> +#include "intel_display_wa.h"
> +
> +#include "xe_device.h"
> +#include "xe_wa.h"
> +
> +#include <generated/xe_wa_oob.h>
> +
> +bool intel_display_needs_wa_16023588340(struct drm_i915_private *i915)
> +{
> +	return XE_WA(xe_root_mmio_gt(i915), 16023588340);

You'll probably want to get verification this is the correct WA number
before pushing this change, but other than that:
Reviewed-by: Jonathan Cavitt <jonathan.cavitt at intel.com>
-Jonathan Cavitt

> +}
> -- 
> 2.45.1
> 
>