bfcpu-freq

#!/bin/sh

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#
# Read the core PLL register to calculate the core clock frequency
#
# F= padfreq*(F+1)/((R+1)*(OD+1))
#
# TYU Boot Record PLL0 register address.offset.length
#
# F: 0x1c0384.3:13
# R: 0x1c0384.20:6
# OD:0x1c0384.16:4
#

F=$(($(mcra mlx5_0 0x1c0384.3:13)))
R=$(($(mcra mlx5_0 0x1c0384.20:6)))
OD=$(($(mcra mlx5_0 0x1c0384.16:4)))

padfreq=156.25 # MHz

freq=$(echo "$F 1 + $padfreq * $R 1 + / $OD 1 + / p"  | dc)

echo "core freq = ${freq}MHz"