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

Dmytro Bablinyuk dmytro.bablinyuk at rftechnology.com.au
Mon May 15 06:59:15 CEST 2006


Hello,

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?

Thank you

Dimitry





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