[PATCH v14 5/9] drm/msm: Add MSM-specific DSC helper methods

From: Jessica Zhang <quic_jesszhan@quicinc.com>
To: <freedreno@lists.freedesktop.org>
Cc: linux-arm-msm@vger.kernel.org,
	Abhinav Kumar <quic_abhinavk@quicinc.com>,
	Kuogee Hsieh <quic_khsieh@quicinc.com>,
	Konrad Dybcio <konrad.dybcio@linaro.org>,
	dri-devel@lists.freedesktop.org,
	Jessica Zhang <quic_jesszhan@quicinc.com>,
	Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
	Marijn Suijten <marijn.suijten@somainline.org>,
	Sean Paul <sean@poorly.run>
Subject: [PATCH v14 5/9] drm/msm: Add MSM-specific DSC helper methods
Date: Wed, 24 May 2023 10:45:18 -0700	[thread overview]
Message-ID: <20230329-rfc-msm-dsc-helper-v14-5-bafc7be95691@quicinc.com> (raw)
In-Reply-To: <20230329-rfc-msm-dsc-helper-v14-0-bafc7be95691@quicinc.com>

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

Reviewed-by: Marijn Suijten <marijn.suijten@somainline.org>
Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
---
 drivers/gpu/drm/msm/msm_dsc_helper.h | 38 ++++++++++++++++++++++++++++++++++++
 1 file changed, 38 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..b9049fe1e279
--- /dev/null
+++ b/drivers/gpu/drm/msm/msm_dsc_helper.h
@@ -0,0 +1,38 @@
+/* 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_ */

-- 
2.40.1

