Re: [PATCH] drm/i915: fix display ver 12-13 fault error handling

[Jani Nikula <jani.nikula@intel.com>]

On Fri, 08 Dec 2023, Jani Nikula <jani.nikula@intel.com> wrote:
> Unless I'm completely misreading the bspec, there are no defined bits
> for plane gtt fault errors in DE PIPE IIR for a display versions
> 12-14. This would explain why DG2 in the linked bug is getting thousands
> of fault errors.
>
> Bspec: 50335
> Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/9769

Okay, looking at the bug, this seems optimistic, but it might clear the
ratelimited fault errors.

> Fixes: 99e2d8bcb887 ("drm/i915/rkl: Limit number of universal planes to 5")
> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
> Cc: Matt Roper <matthew.d.roper@intel.com>
> Cc: Lucas De Marchi <lucas.demarchi@intel.com>
> Cc: <stable@vger.kernel.org> # v5.9+
> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_display_irq.c | 4 +++-
>  drivers/gpu/drm/i915/i915_reg.h                  | 3 ++-
>  2 files changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_display_irq.c b/drivers/gpu/drm/i915/display/intel_display_irq.c
> index f8ed53f30b2e..7bede5b56286 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_irq.c
> +++ b/drivers/gpu/drm/i915/display/intel_display_irq.c
> @@ -834,7 +834,9 @@ static u32 gen8_de_port_aux_mask(struct drm_i915_private *dev_priv)
>  
>  static u32 gen8_de_pipe_fault_mask(struct drm_i915_private *dev_priv)
>  {
> -	if (DISPLAY_VER(dev_priv) >= 13 || HAS_D12_PLANE_MINIMIZATION(dev_priv))
> +	if (DISPLAY_VER(dev_priv) >= 14)
> +		return MTL_DE_PIPE_IRQ_FAULT_ERRORS;
> +	else if (DISPLAY_VER(dev_priv) >= 12)
>  		return RKL_DE_PIPE_IRQ_FAULT_ERRORS;
>  	else if (DISPLAY_VER(dev_priv) >= 11)
>  		return GEN11_DE_PIPE_IRQ_FAULT_ERRORS;
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index 27dc903f0553..fcf980694cb4 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -4354,7 +4354,8 @@
>  	 GEN11_PIPE_PLANE7_FAULT | \
>  	 GEN11_PIPE_PLANE6_FAULT | \
>  	 GEN11_PIPE_PLANE5_FAULT)
> -#define RKL_DE_PIPE_IRQ_FAULT_ERRORS \
> +#define RKL_DE_PIPE_IRQ_FAULT_ERRORS	0
> +#define MTL_DE_PIPE_IRQ_FAULT_ERRORS \
>  	(GEN9_DE_PIPE_IRQ_FAULT_ERRORS | \
>  	 GEN11_PIPE_PLANE5_FAULT)

-- 
Jani Nikula, Intel