[igt-dev] [RFC i-g-t 3/4] lib/igt_kms: Add support for --resolution from igt_runner

[Petri Latvala]

On Fri, May 27, 2022 at 01:43:52PM +0530, Bhanuprakash Modem wrote:
> Upon user request igt_runner will set an environment variable to choose
> default DRM display mode for subtests instead of taking the preferred
> mode.
> 
> Example:
> Eventhough we have an 8K panel, Kernel may expose 4K or lesser mode
> as a preferred mode. So all subtests will take this mode as a default
> may cause losing the coverage.
> 
> This patch will parse the environment variable exposed by igt_runner
> and take the decision to choose the mode from the available list.
> 
> The default is still to take the preferred mode exposed by the Kernel.
> Other options are:
>  * highest: Choose the mode with highest possible resolution.
>  * lowest:  Choose the mode with lowest possible resolution.
> 
> Cc: Petri Latvala <petri.latvala at intel.com>
> Cc: Swati Sharma <swati2.sharma at intel.com>
> Signed-off-by: Bhanuprakash Modem <bhanuprakash.modem at intel.com>
> ---
>  lib/igt_kms.c | 37 ++++++++++++++++++++++++++++++++++++-
>  1 file changed, 36 insertions(+), 1 deletion(-)
> 
> diff --git a/lib/igt_kms.c b/lib/igt_kms.c
> index 84e798b5..aa964e11 100644
> --- a/lib/igt_kms.c
> +++ b/lib/igt_kms.c
> @@ -1431,6 +1431,20 @@ void kmstest_force_edid(int drm_fd, drmModeConnector *connector,
>  	igt_assert(ret != -1);
>  }
>  
> +static int sort_drm_modes_asc(const void *a, const void *b)
> +{
> +	const drmModeModeInfo *mode1 = a, *mode2 = b;
> +
> +	return (mode1->hdisplay > mode2->hdisplay) - (mode2->hdisplay > mode1->hdisplay);
> +}
> +
> +static int sort_drm_modes_dsc(const void *a, const void *b)
> +{
> +	const drmModeModeInfo *mode1 = a, *mode2 = b;
> +
> +	return (mode1->hdisplay < mode2->hdisplay) - (mode2->hdisplay < mode1->hdisplay);
> +}
> +
>  /**
>   * kmstest_get_connector_default_mode:
>   * @drm_fd: DRM fd
> @@ -1444,7 +1458,13 @@ void kmstest_force_edid(int drm_fd, drmModeConnector *connector,
>  bool kmstest_get_connector_default_mode(int drm_fd, drmModeConnector *connector,
>  					drmModeModeInfo *mode)
>  {
> -	int i;
> +	enum {
> +		RESOLUTION_DEFAULT = 0,
> +		RESOLUTION_HIGHEST,
> +		RESOLUTION_LOWEST,
> +	};
> +	char *env;
> +	int i, res = RESOLUTION_DEFAULT;
>  
>  	if (!connector->count_modes) {
>  		igt_warn("no modes for connector %d\n",
> @@ -1452,6 +1472,21 @@ bool kmstest_get_connector_default_mode(int drm_fd, drmModeConnector *connector,
>  		return false;
>  	}
>  
> +	env = getenv("IGT_KMS_RESOLUTION");
> +	if (env)
> +		res = atoi(env);

With what I replied to the igt_runner patch in mind, the parsing of
the strings "highest" and "lowest" would have to be done here instead
of in the runner.


-- 
Petri Latvala


> +
> +	if (res) {
> +		qsort(connector->modes,
> +		      connector->count_modes,
> +		      sizeof(drmModeModeInfo),
> +		      (res == RESOLUTION_HIGHEST) ?
> +			sort_drm_modes_dsc : sort_drm_modes_asc);
> +
> +		*mode = connector->modes[0];
> +		return true;
> +	}
> +
>  	for (i = 0; i < connector->count_modes; i++) {
>  		if (i == 0 ||
>  		    connector->modes[i].type & DRM_MODE_TYPE_PREFERRED) {
> -- 
> 2.35.1
>