AM335X 设备树修改MPU电压，报错问题

DTS :
dcdc2_reg: regulator@1 [
/* VDD_MPU voltage limits 0.95V - 1.325V with +/-4% tolerance */
regulator-name = "vdd_mpu";
regulator-min-microvolt = <925000>;
regulator-max-microvolt = <1378000>;
regulator-boot-on;
regulator-always-on;
];
regulator-min-microvolt = <1250000>;
regulator-max-microvolt = <1280000>;
修改最大电压为1.28V
系统运行后，电压确实1.28V 

但系统打印会报错，不知道是什么原因？求指点！谢谢了
[ 1.723441] remoteproc0: Direct firmware load failed with error -2
[ 1.730025] remoteproc0: Falling back to user helper
[ 1.735785] cpu cpu0: of_pm_voltdm_notifier_register: Fail calculating voltage latency[950000<->1325000]:-22
[ 1.746651] vdd_mpu: unsupportable voltage range: 1325000-1275000uV
[ 1.753254] vdd_mpu: unsupportable voltage range: 1298500-1275000uV
[ 1.759835] cpu cpu0: clk_voltdm_notifier_handler: Failed to scale voltage(1325000): -22
[ 1.768302] clk_set_rate: failed to set dpll_mpu_ck rate
[ 1.775052] cpufreq_cpu0: failed to set clock rate: -16
[ 1.780545] cpufreq: __cpufreq_driver_target: Failed to change cpu frequency: -16
[ 1.839120] vdd_mpu: unsupportable voltage range: 1325000-1275000uV
[ 1.845678] vdd_mpu: unsupportable voltage range: 1298500-1275000uV
[ 1.852251] cpu cpu0: clk_voltdm_notifier_handler: Failed to scale voltage(1325000): -22
[ 1.860725] clk_set_rate: failed to set dpll_mpu_ck rate
[ 1.867494] cpufreq_cpu0: failed to set clock rate: -16
[ 1.872972] cpufreq: __cpufreq_driver_target: Failed to change cpu frequency: -16
[ 1.939125] davinci_mdio 4a101000.mdio: davinci mdio revision 1.6