error cpu rate

[ricar]

Hi,
I have been using  A20-Olinuxino LIME board, with a Linux Debian image booted from NAND. The board is connected with USB serial cable to my PC. This morning I found this error :

<3>[ccu-err] rate (336000000) is invalid when set cpu rate (408000000)

[26101.732983] [ccu-err] rate (336000000) is invalid when set cpu rate (408000000)
<3>[ccu-err] 0xf1c20000 = 0xa1005100

[26101.743616] [ccu-err] 0xf1c20000 = 0xa1005100
<3>[ccu-err] clk_set_rate: set cpu rate to 336000000 failed

[26101.753346] [ccu-err] clk_set_rate: set cpu rate to 336000000 failed
<3>[cpu_freq] ERR:try to set target frequency failed!

[26101.765527] [cpu_freq] ERR:try to set target frequency failed!
<3>[cpu_freq] ERR:no compatible settings cpu freq for 336000000

[26101.777916] [cpu_freq] ERR:no compatible settings cpu freq for 336000000
<3>[ccu-err] rate (336000000) is invalid when set cpu rate (408000000)

[72743.078108] [ccu-err] rate (336000000) is invalid when set cpu rate (408000000)
<3>[ccu-err] 0xf1c20000 = 0xa1005100

[72743.088741] [ccu-err] 0xf1c20000 = 0xa1005100
<3>[ccu-err] clk_set_rate: set cpu rate to 336000000 failed

[72743.102406] [ccu-err] clk_set_rate: set cpu rate to 336000000 failed
<3>[cpu_freq] ERR:try to set target frequency failed!

[72743.113652] [cpu_freq] ERR:try to set target frequency failed!
<3>[cpu_freq] ERR:no compatible settings cpu freq for 336000000

[72743.126363] [cpu_freq] ERR:no compatible settings cpu freq for 336000000.

What does it means? Thanks.