How to change the kernel command line?

bzhao

Under rv1126 Linux, in kernel DTS, I change like this:  
       chosen {
-               bootargs = "earlycon=uart8250,mmio32,0xff570000 console=ttyFIQ0 ro root=PARTLABEL=rootfs rootfstype=ext4 rootwait overlayroot=device:dev=PARTLABEL=userdata,fstype=ext4,mkfs=1 cgroup_enable=memory swapaccount=1 snd_aloop.index=7";
+               bootargs = "earlycon=uart8250,mmio32,0xff570000 console=ttyFIQ0 ro root=PARTLABEL=rootfs rootfstype=ext4 rootwait overlayroot=device:dev=PARTLABEL=userdata,fstype=ext4,mkfs=1 cgroup_enable=memory swapaccount=1 snd_aloop.index=7 loglevel=8";
        };

the logleve=8 is available after bootting, but it sound it does not works as expected