[PATCH v10 4/8] drm/msm: Add MSM-specific DSC helper methods

[Jessica Zhang]

Introduce MSM-specific DSC helper methods, as some calculations are
common between DP and DSC.

Signed-off-by: Jessica Zhang <quic_jesszhan at quicinc.com>
---
 drivers/gpu/drm/msm/msm_dsc_helper.h | 65 ++++++++++++++++++++++++++++++++++++
 1 file changed, 65 insertions(+)

diff --git a/drivers/gpu/drm/msm/msm_dsc_helper.h b/drivers/gpu/drm/msm/msm_dsc_helper.h
new file mode 100644
index 000000000000..0d2a097b428d
--- /dev/null
+++ b/drivers/gpu/drm/msm/msm_dsc_helper.h
@@ -0,0 +1,65 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved
+ */
+
+#ifndef MSM_DSC_HELPER_H_
+#define MSM_DSC_HELPER_H_
+
+#include <linux/bug.h>
+#include <linux/math.h>
+#include <drm/display/drm_dsc_helper.h>
+
+/*
+ * Helper methods for MSM specific DSC calculations that are common between timing engine,
+ * DSI, and DP.
+ */
+
+/**
+ * msm_dsc_get_bpp_int() - get bits per pixel integer value
+ * @dsc: Pointer to drm dsc config struct
+ * Returns: BPP integer value
+ */
+static inline int msm_dsc_get_bpp_int(struct drm_dsc_config *dsc)
+{
+	WARN_ON_ONCE(dsc->bits_per_pixel & 0xf);
+	return dsc->bits_per_pixel >> 4;
+}
+
+/**
+ * msm_dsc_get_slice_per_intf() - get number of slices per interface
+ * @dsc: Pointer to drm dsc config struct
+ * @intf_width: interface width
+ * Returns: Integer representing the slice per interface
+ */
+static inline int msm_dsc_get_slice_per_intf(struct drm_dsc_config *dsc, int 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 pclk per interface
+ *
+ * Note: This value will then be passed along to DSI and DP for some more
+ * calculations. This is because DSI and DP divide the pclk_per_intf value
+ * by different values depending on if widebus is enabled.
+ */
+static inline int msm_dsc_get_bytes_per_line(struct drm_dsc_config *dsc)
+{
+	return dsc->slice_count * dsc->slice_chunk_size;
+}
+
+/**
+ * msm_dsc_get_bytes_per_intf() - get total bytes per interface
+ * @dsc: Pointer to drm dsc config struct
+ * @intf_width: interface width
+ * Returns: u32 value representing bytes per interface
+ */
+static inline u32 msm_dsc_get_bytes_per_intf(struct drm_dsc_config *dsc, int intf_width)
+{
+	return dsc->slice_chunk_size * msm_dsc_get_slice_per_intf(dsc, intf_width);
+}
+
+#endif /* MSM_DSC_HELPER_H_ */

-- 
2.40.1