[PATCH v2 4/4] drm/amd/display: Rewrite CalculateWriteBackDISPCLK function

[Maíra Canal]

Based on the dml30_CalculateWriteBackDISPCLK, it separates the
DISPCLK calculations on three variables, making no functional changes, in order
to make it more readable and better express that three values are being compared
on dml_max.

Signed-off-by: Maíra Canal <mairacanal at riseup.net>
Reviewed-by: André Almeida <andrealmeid at igalia.com>
---
 .../drm/amd/display/dc/dml/display_mode_vba.c | 29 ++++++++++++-------
 1 file changed, 18 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/dml/display_mode_vba.c b/drivers/gpu/drm/amd/display/dc/dml/display_mode_vba.c
index 503e7d984ff0..df80c79d8fbc 100644
--- a/drivers/gpu/drm/amd/display/dc/dml/display_mode_vba.c
+++ b/drivers/gpu/drm/amd/display/dc/dml/display_mode_vba.c
@@ -1115,20 +1115,27 @@ double CalculateWriteBackDISPCLK(
 		unsigned int HTotal,
 		unsigned int WritebackChromaLineBufferWidth)
 {
-	double CalculateWriteBackDISPCLK = 1.01 * PixelClock * dml_max(
-		dml_ceil(WritebackLumaHTaps / 4.0, 1) / WritebackHRatio,
-		dml_max((WritebackLumaVTaps * dml_ceil(1.0 / WritebackVRatio, 1) * dml_ceil(WritebackDestinationWidth / 4.0, 1)
+	double DISPCLK_H, DISPCLK_V, DISPCLK_HB, CalculateWriteBackDISPCLK;
+
+	DISPCLK_H = dml_ceil(WritebackLumaHTaps / 4.0, 1) / WritebackHRatio;
+	DISPCLK_V = (WritebackLumaVTaps * dml_ceil(1.0 / WritebackVRatio, 1) * dml_ceil(WritebackDestinationWidth / 4.0, 1)
 			+ dml_ceil(WritebackDestinationWidth / 4.0, 1)) / (double) HTotal + dml_ceil(1.0 / WritebackVRatio, 1)
-			* (dml_ceil(WritebackLumaVTaps / 4.0, 1) + 4.0) / (double) HTotal,
-			dml_ceil(1.0 / WritebackVRatio, 1) * WritebackDestinationWidth / (double) HTotal));
+			* (dml_ceil(WritebackLumaVTaps / 4.0, 1) + 4.0) / (double) HTotal;
+	DISPCLK_HB = dml_ceil(1.0 / WritebackVRatio, 1) * WritebackDestinationWidth / (double) HTotal;
+
+	CalculateWriteBackDISPCLK = 1.01 * PixelClock * dml_max3(DISPCLK_H, DISPCLK_V, DISPCLK_HB);
+
 	if (WritebackPixelFormat != dm_444_32) {
-		CalculateWriteBackDISPCLK = dml_max(CalculateWriteBackDISPCLK, 1.01 * PixelClock * dml_max(
-			dml_ceil(WritebackChromaHTaps / 2.0, 1) / (2 * WritebackHRatio),
-			dml_max((WritebackChromaVTaps * dml_ceil(1 / (2 * WritebackVRatio), 1) * dml_ceil(WritebackDestinationWidth / 2.0 / 2.0, 1)
-				+ dml_ceil(WritebackDestinationWidth / 2.0 / WritebackChromaLineBufferWidth, 1)) / HTotal
-				+ dml_ceil(1 / (2 * WritebackVRatio), 1) * (dml_ceil(WritebackChromaVTaps / 4.0, 1) + 4) / HTotal,
-				dml_ceil(1.0 / (2 * WritebackVRatio), 1) * WritebackDestinationWidth / 2.0 / HTotal)));
+		DISPCLK_H = dml_ceil(WritebackChromaHTaps / 2.0, 1) / (2 * WritebackHRatio);
+		DISPCLK_V = (WritebackChromaVTaps * dml_ceil(1 / (2 * WritebackVRatio), 1) *
+				dml_ceil(WritebackDestinationWidth / 4.0, 1) +
+				dml_ceil(WritebackDestinationWidth / 2.0 / WritebackChromaLineBufferWidth, 1)) / HTotal +
+			dml_ceil(1 / (2 * WritebackVRatio), 1) *(dml_ceil(WritebackChromaVTaps / 4.0, 1) + 4) / HTotal;
+		DISPCLK_HB = dml_ceil(1.0 / (2 * WritebackVRatio), 1) * WritebackDestinationWidth / 2.0 / HTotal;
+		CalculateWriteBackDISPCLK = dml_max(CalculateWriteBackDISPCLK,
+				1.01 * PixelClock * dml_max3(DISPCLK_H, DISPCLK_V, DISPCLK_HB));
 	}
+
 	return CalculateWriteBackDISPCLK;
 }
 
-- 
2.36.1