drm/msm: Add MSM-specific DSC helper methods

/* SPDX-License-Identifier: GPL-2.0-only */

/*

 * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved

 *

 * Helper methods for MSM-specific DSC calculations that are common between timing engine,

 * DSI, and DP.

 */

#ifndef MSM_DSC_HELPER_H_

#define MSM_DSC_HELPER_H_

#include <linux/math.h>

#include <drm/display/drm_dsc_helper.h>

/**

 * msm_dsc_get_slices_per_intf() - calculate number of slices per interface

 * @dsc: Pointer to drm dsc config struct

 * @intf_width: interface width in pixels

 * Returns: Integer representing the number of slices for the given interface

 */

static inline u32 msm_dsc_get_slices_per_intf(const struct drm_dsc_config *dsc, u32 intf_width)

{

	return DIV_ROUND_UP(intf_width, dsc->slice_width);

}

/**

 * msm_dsc_get_bytes_per_line() - calculate bytes per line

 * @dsc: Pointer to drm dsc config struct

 * Returns: Integer value representing bytes per line. DSI and DP need

 *          to perform further calculations to turn this into pclk_per_intf,

 *          such as dividing by different values depending on if widebus is enabled.

 */

static inline u32 msm_dsc_get_bytes_per_line(const struct drm_dsc_config *dsc)

{

	return dsc->slice_count * dsc->slice_chunk_size;

}

#endif /* MSM_DSC_HELPER_H_ */