[igt-dev] [PATCH] lib/igt_kms: Add a helper function to check Bigjoiner support

[Navare, Manasi]

On Mon, May 02, 2022 at 08:21:14PM +0530, Bhanuprakash Modem wrote:
> Create a helper function to check that the system supports the
> given crtc/connector mode(s).
> 
> Example: Pipe-D won't support Bigjoiner, hence we can't use the
> connector modes greater than 5K on Pipe-D
> 
> To use this helper, each individual subtest needs to set the
> @pipe to a specific @output by igt_output_set_pipe() and call
> this helper to check the validity of the combo.

Thank you for taking a stab at cleaning this up and adding this check in
IGT.

In all cases, always the bigjoiner can only be supported on pipes 0 -
total_pipes - 1
So say the total pipes available in the platform are n, any mode > 5K
can only be requested on pipes 0- n-1 and will be rejected on pipe n.

Cant we just use this simple check in igt_check_bigjoiner_support() {

total_pipes = n; (based on platform hardcode that say now for all
platforms that support bigjoiner, total_pipes = 4)
If mode > 5K and pipe = 4,
skip test
}

Manasi

> 
> Signed-off-by: Bhanuprakash Modem <bhanuprakash.modem at intel.com>
> ---
>  lib/igt_kms.c | 66 +++++++++++++++++++++++++++++++++++++++++++++++++++
>  lib/igt_kms.h |  2 ++
>  2 files changed, 68 insertions(+)
> 
> diff --git a/lib/igt_kms.c b/lib/igt_kms.c
> index 7838ff28..e277193d 100644
> --- a/lib/igt_kms.c
> +++ b/lib/igt_kms.c
> @@ -5379,3 +5379,69 @@ int igt_get_dsc_debugfs_fd(int drmfd, drmModeConnector *connector)
>  
>  	return openat(igt_debugfs_dir(drmfd), file_name, O_WRONLY);
>  }
> +
> +/*
> + * igt_check_bigjoiner_support:
> + * @display: a pointer to an #igt_display_t structure
> + *
> + * Get all active pipes from connected outputs (i.e. pending_pipe != PIPE_NONE)
> + * and check those pipes supports the selected mode(s).
> + *
> + * Example: Pipe-D can't support mode > 5K
> + *
> + * Returns: true if a valid crtc/connector mode combo found, else false
> + */
> +bool igt_check_bigjoiner_support(igt_display_t *display)
> +{
> +	uint8_t i, total_pipes = 0, active_pipes = 0;
> +	enum pipe p;
> +	struct {
> +		enum pipe idx;
> +		drmModeModeInfo *mode;
> +	} pipes[IGT_MAX_PIPES];
> +
> +	/* Get total enabled pipes. */
> +	for_each_pipe(display, p)
> +		total_pipes++;
> +
> +	/*
> +	 * Get list of active pipes those were set by igt_output_set_pipe()
> +	 * just before calling this function.
> +	 */
> +	for (i = 0 ; i < display->n_outputs; i++) {
> +		igt_output_t *output = &display->outputs[i];
> +
> +		if (output->pending_pipe == PIPE_NONE)
> +			continue;
> +
> +		pipes[active_pipes].idx = output->pending_pipe;
> +		pipes[active_pipes].mode = igt_output_get_mode(output);
> +		active_pipes++;
> +	}
> +
> +	if (active_pipes)
> +		return true;
> +
> +	/*
> +	 * if mode.hdisplay > 5120, then ignore
> +	 *  - last crtc in single/multi-connector config
> +	 *  - consecutive crtcs in multi-connector config
> +	 *
> +	 * in multi-connector config ignore if
> +	 *  - previous crtc mode.hdisplay > 5120 and
> +	 *  - current & previous crtcs are consecutive
> +	 */
> +	for (i = 0; i < active_pipes; i++) {
> +		if (((pipes[i].mode->hdisplay > MAX_HDISPLAY_PER_PIPE) &&
> +		     ((pipes[i].idx >= (total_pipes - 1)) ||
> +		      ((i < (active_pipes - 1)) && (abs(pipes[i + 1].idx - pipes[i].idx) <= 1)))) ||
> +		    ((i > 0) && (pipes[i - 1].mode->hdisplay > MAX_HDISPLAY_PER_PIPE) &&
> +		     (abs(pipes[i].idx - pipes[i - 1].idx) <= 1))) {
> +			igt_debug("CRTC/Connector is not possible with selected mode(s).\n");
> +
> +			return false;
> +		}
> +	}
> +
> +	return true;
> +}
> diff --git a/lib/igt_kms.h b/lib/igt_kms.h
> index e9ecd21e..8a14bb3c 100644
> --- a/lib/igt_kms.h
> +++ b/lib/igt_kms.h
> @@ -109,6 +109,7 @@ const char *kmstest_connector_status_str(int status);
>  const char *kmstest_connector_type_str(int type);
>  
>  void kmstest_dump_mode(drmModeModeInfo *mode);
> +#define MAX_HDISPLAY_PER_PIPE 5120
>  
>  int kmstest_get_pipe_from_crtc_id(int fd, int crtc_id);
>  void kmstest_set_vt_graphics_mode(void);
> @@ -947,5 +948,6 @@ int igt_force_dsc_enable(int drmfd, drmModeConnector *connector);
>  int igt_force_dsc_enable_bpp(int drmfd, drmModeConnector *connector,
>  				int bpp);
>  int igt_get_dsc_debugfs_fd(int drmfd, drmModeConnector *connector);
> +bool igt_check_bigjoiner_support(igt_display_t *display);
>  
>  #endif /* __IGT_KMS_H__ */
> -- 
> 2.35.1
>