[U-Boot] [PATCH v3 22/23] tegra: fdt: Add EMC data for Tegra2 Seaboard

[Simon Glass]

Hi,

On Tue, Apr 3, 2012 at 5:47 PM, Simon Glass <sjg at chromium.org> wrote:
> Hi Olof,
>
> On Mon, Apr 2, 2012 at 10:22 PM, Olof Johansson <olof at lixom.net> wrote:
>> On Mon, Apr 2, 2012 at 4:19 PM, Simon Glass <sjg at chromium.org> wrote:
>>> This adds timings for T20 and T25 Seaboards, using the bindings found here:
>>>
>>> http://patchwork.ozlabs.org/patch/132928/
>>>
>>> We supply both full speed options for normal running, and half speed options
>>> for testing / development.
>>>
>>> Signed-off-by: Simon Glass <sjg at chromium.org>
>>
>> This seems incorrect to me. You provide both T20 and T25 EMC tables in
>> the same device tree with no way to determine which one to use.
>>
>> Unfortunately nvidia didn't use the boot straps to tell if they were
>> on a t20 or t25 seaboard, so you'll just have to know. At the kernel
>> side we chose to just ditch T20 since most boards still in use are
>> T25.
>
> The selection of memory speed is down to the board. There is a later
> patch in this series (just cc'd to you) which looks at the SOC ID to
> determine whether it is T20 or T25, and selects the speed accordingly.
> This speed is used to look up the correct table in the device tree

Well if we really want to do this properly we should have a separate
device tree file for the T20 Seaboard. Since the kernel has dropped
T20 support, we should do the same. I have updated this patch.

Regards,
Simon

>
>>
>>
>>
>> -Olof
>
> Regards,
> Simon