[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
More information about the U-Boot
mailing list