[U-Boot-Users] RE: SCMR[PLLMF] and HRCW for MPC8272

Bastos Fernandez Alexandre ALEBAS at televes.com
Thu May 18 10:04:37 CEST 2006


Dmytro,

> I am trying to bring up a custom 8272 board.
> I set HRCW to 0x0A74B20A and on output I have
> 
> --8<---
> MPC8272 Clock Configuration
>   - Bus-to-Core Mult 4x, VCO Div 2, 60x Bus Freq  25-75 , Core Freq
> 100-300
>   - dfbrg 1, corecnf 0x1a, busdf 5, cpmdf 1, plldf 0, pllmf 2
>   - vco_out  198000000, scc_clk   49500000, brg_clk   12375000
>   - cpu_clk  264000000, cpm_clk   99000000, bus_clk   66000000
>   - pci_clk   33000000
> 
> CPU:   MPC8272 (HiP7 Rev 14, Mask 1.0 1K50M) at 264 MHz
> <HANGS HERE..>
> --8<---
> 
> BUS_CLK=66MHz - Correct.
> CPU_CLK=264MHz - Correct
> BUSDF=5 - Wrong! Should be BUSDF=3
> PLLMF=2 - Wrong! Should be PLLMF=3
> CPM_CLK=99MHz - Wrong! Should be 132MHz
> ( PLLMF = 2(CPM_CLK/CLKIN)-1 => which gives us CPM_CLK = 99MHz )
> 
> The problem is that PLLMF should be 3 that will give us CPM_CLK=132MHz.
> 
> I am using MODCK_H=1010 and PCI_MODCK=0 which according to clock 
> configuration for PCI host mode should give CPM multiplication factor 
> equals 2 and PLLMF=3. But PLLMF still gives me 2!
> 
> Can anybody help me please, what I am missing? How do I get PLLMF=3 in
> SCMR?
> 
In the Clock Configurations for PCI Host Mode and PCI_MODCK=0 in the
Hadrware Specifications doc. from Freescale I couldn't find any options for
MODCK_H=1010 and bus_CLK of 66MHz. Check this, maybe the problem
is about that.

Couls you also check the MODCK[1-3] hardware pins and report?

Best regards

Alex BASTOS





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