Re: [PATCH i-g-t v2 8/8] tests/intel/kms_fbcon_fbt: use a common source for checking fbc tests skips

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

On Tue, 07 Apr 2026, Vinod Govindapillai <vinod.govindapillai@intel.com> wrote:
> There could be few reasons where fbc cannot be enabled and the tests
> could be skipped. There is a common array declarred in intel_fbc.h
> which act as source of fbc skip reasons for kms_frontbuffer_tracking
> tests. Use that array for kms_fbcon_fbt tests as well and also update
> the array with reasons from this tests also. All those reasons are
> valid and declared by the driver as a reason for not enabling FBC in
> a pipe.
>
> Signed-off-by: Vinod Govindapillai <vinod.govindapillai@intel.com>
> ---
>  lib/i915/intel_fbc.h        |  7 +++++++
>  tests/intel/kms_fbcon_fbt.c | 16 ++--------------
>  2 files changed, 9 insertions(+), 14 deletions(-)
>
> diff --git a/lib/i915/intel_fbc.h b/lib/i915/intel_fbc.h
> index 3dd15de31..2b6f21bc4 100644
> --- a/lib/i915/intel_fbc.h
> +++ b/lib/i915/intel_fbc.h
> @@ -14,10 +14,17 @@ enum psr_mode;
>  
>  const char *const no_fbc_reasons[] = {
>  	"FBC disabled: not enough stolen memory",
> +	"FBC disabled: pixel format not supported",
> +	"FBC disabled: tiling not supported",
> +	"FBC disabled: rotation not supported",
>  	"FBC disabled: stride not supported",
> +	"FBC disabled: per-pixel alpha not supported",
>  	"FBC disabled: plane size too big",
>  	"FBC disabled: surface size too big",
>  	"FBC disabled: PSR1 enabled (Wa_14016291713)"
> +	"FBC disabled: plane start Y offset misaligned",
> +	"FBC disabled: plane end Y offset misaligned",
> +	"FBC disabled: pixel rate too high"
>  };
>  
>  void intel_fbc_enable(igt_display_t *display);
> diff --git a/tests/intel/kms_fbcon_fbt.c b/tests/intel/kms_fbcon_fbt.c
> index 78c6cc4b2..95a4f66b7 100644
> --- a/tests/intel/kms_fbcon_fbt.c
> +++ b/tests/intel/kms_fbcon_fbt.c
> @@ -296,18 +296,6 @@ static inline void psr_debugfs_enable(int device, int debugfs_fd)
>  
>  static void fbc_skips_on_fbcon(int debugfs_fd)
>  {
> -	const char *reasons[] = {
> -		"pixel format not supported",
> -		"tiling not supported",
> -		"rotation not supported",
> -		"stride not supported",
> -		"per-pixel alpha not supported",
> -		"plane size too big",
> -		"surface size too big",
> -		"plane start Y offset misaligned",
> -		"plane end Y offset misaligned",
> -		"pixel rate too high"
> -	};
>  	bool skip = false;
>  	char buf[FBC_STATUS_BUF_LEN];
>  	int i;
> @@ -316,8 +304,8 @@ static void fbc_skips_on_fbcon(int debugfs_fd)
>  	if (strstr(buf, "FBC enabled\n"))
>  		return;
>  
> -	for (i = 0; skip == false && i < ARRAY_SIZE(reasons); i++)
> -		skip = strstr(buf, reasons[i]);
> +	for (i = 0; !skip && i < ARRAY_SIZE(no_fbc_reasons); i++)
> +		skip = strstr(buf, no_fbc_reasons[i]);

IMO this kind of loop should be in intel_fbc.c.

>  
>  	igt_skip_on_f(skip, "fbcon modeset is not compatible with FBC\n");
>  }

-- 
Jani Nikula, Intel