[coreboot] [RFC] [PATCH] Overclocking support for 939a785gmh

Rudolf Marek r.marek at assembler.cz
Tue Jan 25 21:24:12 CET 2011

Hi all,

Attached patch adds support for CMOS options which can alter DDR Memory, HT GPU, 
and Sideport Voltages. Also as a quick hack it can change CPU base frequency 
from 200MHz to something else.

I think this would be nice to show on FOSDEM.It could be extended so not only 
CPU PLL is programmed but also PCIe etc, also one could adjust the DDR divisors 
so the memory runs still like on 200MHz (same for HT). Also FID could be 
changed, but this is not implemented yet. The CPU voltage changes are possible 
too. It is just a question of writing to SIO...

boot_option = Fallback
last_boot = Fallback
ECC_memory = Disable
baud_rate = 115200
debug_level = Info
power_on_after_fail = Disable
hw_scrubber = Disable
nmi = Disable
iommu = Enable
interleave_chip_selects = Enable
multi_core = Enable
slow_cpu = off
max_mem_clock = DDR400
cmos_defaults_loaded = Disable
ht_voltage = 1.30V
sideport_voltage = 1.82V
gpu_voltage = 1.10V
memory_voltage = 2.60V
cpu_freq = 210MHz

Although it is bit hackish I do

Signed-off-by: Rudolf Marek <r.marek at assembler.cz>

If someone has similar/same board and has more time to work on this it would be 
very nice!

Not sure If I will be able to prepare it to comittable state before FOSDEM.

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