[igt-dev] [i-g-t V2] lib/igt_kms: Choose default mode based on --environment flag from igt_runner

[Petri Latvala]

On Thu, Sep 01, 2022 at 09:01:18PM +0530, Bhanuprakash Modem wrote:
> igt_runner provides --environment flag KEY=VALUE pair as the environment
> variable to execute test processes. 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.
> 
> Possible options are:
>   0/lowest: Choose the mode with lowest possible resolution.
>   1/highest: Choose the mode with highest possible resolution.
> 
> By default (without this flag) fallback to take the preferred mode exposed
> by the Kernel.
> 
> Usage:
> ./igt_runner --environment "IGT_KMS_RESOLUTION=1" ...
> ./igt_runner --environment "IGT_KMS_RESOLUTION=lowest" ...
> 
> V2:
> - Allow "lowest" & "highest" options too
> 
> Cc: Petri Latvala <petri.latvala at intel.com>
> Cc: Swati Sharma <swati2.sharma at intel.com>
> Cc: Karthik B S <karthik.b.s at intel.com>
> Signed-off-by: Bhanuprakash Modem <bhanuprakash.modem at intel.com>

Reviewed-by: Petri Latvala <petri.latvala at intel.com>

> ---
>  lib/igt_kms.c | 21 +++++++++++++++++++++
>  1 file changed, 21 insertions(+)
> 
> diff --git a/lib/igt_kms.c b/lib/igt_kms.c
> index 1ba3bd2a..7d4916a7 100644
> --- a/lib/igt_kms.c
> +++ b/lib/igt_kms.c
> @@ -1586,6 +1586,7 @@ void igt_sort_connector_modes(drmModeConnector *connector,
>  bool kmstest_get_connector_default_mode(int drm_fd, drmModeConnector *connector,
>  					drmModeModeInfo *mode)
>  {
> +	char *env;
>  	int i;
>  
>  	if (!connector->count_modes) {
> @@ -1594,6 +1595,26 @@ bool kmstest_get_connector_default_mode(int drm_fd, drmModeConnector *connector,
>  		return false;
>  	}
>  
> +	env = getenv("IGT_KMS_RESOLUTION");
> +	if (env) {
> +		/*
> +		 * Only (0 or 1) and (lowest or highest) are allowed.
> +		 *
> +		 * 0/lowest: Choose connector mode with lowest possible resolution.
> +		 * 1/highest: Choose connector mode with highest possible resolution.
> +		 */
> +		if (!strcmp(env, "highest") || !strcmp(env, "1"))
> +			igt_sort_connector_modes(connector, sort_drm_modes_by_res_dsc);
> +		else if (!strcmp(env, "lowest") || !strcmp(env, "0"))
> +			igt_sort_connector_modes(connector, sort_drm_modes_by_res_asc);
> +		else
> +			goto default_mode;
> +
> +		*mode = connector->modes[0];
> +		return true;
> +	}
> +
> +default_mode:
>  	for (i = 0; i < connector->count_modes; i++) {
>  		if (i == 0 ||
>  		    connector->modes[i].type & DRM_MODE_TYPE_PREFERRED) {
> -- 
> 2.35.1
>