[U-Boot] ODROID dynamic memory initialization

Daniel Drake drake at endlessm.com
Wed Jul 23 14:27:30 CEST 2014


On Tue, Jul 22, 2014 at 2:08 PM, Daniel Drake <drake at endlessm.com> wrote:
> While looking at the old uboot from hardkernel, I'm curious about
> CONFIG_CLK_BUS_DMC_220_440, which is set by default. This appears to
> run the memory at a high speed, by writing certain registers in the
> Dynamic Memory Controller (e.g. TIMINGROW), and clocking MPLL to
> 880MHz.
>
> Your uboot patches don't seem to touch DMC regs like TIMINGROW, and
> also clock the MPLL at 800MHz.

I looked in more detail, and now understand better the SPL vs uboot division.

The vendor code I was referring to above is SPL code.

Since we are still using the same SPL as before, it means that MPLL
and memory is already set up by the time the real/new uboot loads.

So I think there should be no need to modify MPLL, and I wonder if
most of the other clock configuration code in your patches is also
unnecessary.

Thoughts?

Thanks
Daniel


More information about the U-Boot mailing list