core/lib/clock.c

100 	 *    dev_freq_khz * 1000 / 2^shift_constant = 1 scaled_ppm
101 	 *    ppb = scaled_ppm * 1000 / 2^16
105 	 *    dev_freq_khz * 1000 / 1 scaled_ppm = 2^shift_constant
395 static int mlx5_ptp_freq_adj_real_time(struct mlx5_core_dev *mdev, long scaled_ppm)
402 	    scaled_ppm <= S32_MAX && scaled_ppm >= S32_MIN) {
403 		/* HW scaled_ppm support on mlx5 devices only supports a 32-bit value */
406 		MLX5_SET(mtutc_reg, in, freq_adjustment, (s32)scaled_ppm);
409 		MLX5_SET(mtutc_reg, in, freq_adjustment, scaled_ppm_to_ppb(scaled_ppm));
415 static int mlx5_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
426 		int err = mlx5_ptp_freq_adj_real_time(mdev, scaled_ppm);
432 	mult = (u32)adjust_by_scaled_ppm(timer->nominal_c_mult, scaled_ppm);