[U-Boot] [PATCH] i.MX28: Add function to adjust memory parameters

[Marek Vasut]

Dear Fabio Estevam,

> Hi Marek,
> 
> On Wed, May 30, 2012 at 2:43 AM, Marek Vasut <marex at denx.de> wrote:
> > This function can be overridden at run-time and allows implementors
> > of new boards based on the i.MX28 chip to fine-tune the memory params.
> > It is possible to write into the dram_vals array because when the SPL
> > runs, it is located SRAM. Therefore the location is writable. There is
> > no possibility of these data to be read-only.
> 
> This still does not fix the mx28evk booting issue on u-boot-imx tree.
> 
> Have you tried to boot m28evk with the following commit reverted?

It's broken, that's why the following patch was applied ;-)

Call this or similar in your spl_boot.c to adjust the DRAM configuration. 
Actually I think even the following value should fix your problem:

void mx28_adjust_memory_params(uint32_t *dram_vals)
{
        dram_vals[0x74 >> 2] = 0x0f02010a;
}

> 
> commit 19a2066b578f826c7bcb2b96a90434382e8ec8f3
> Author: Marek Vasut <marex at denx.de>
> Date:   Thu May 3 05:47:19 2012 +0000
> 
>     M28: Scan only first 512 MB of DRAM to avoid memory wraparound

Best regards,
Marek Vasut