[U-Boot] [PATCH 26/34] imx: ventana: add DT fixup for GW54xx compatibility with older kernels

[Tim Harvey]

On Thu, Apr 16, 2015 at 12:46 AM, Stefano Babic <sbabic at denx.de> wrote:
> Hi Tim,
>
> I have no problem with the whole series, I will start to apply. Just a
> couple of questions:
>
> On 08/04/2015 21:54, Tim Harvey wrote:
>> Certain older kernels in use by some customers erroneously define a uart3
>> for GW54xx with a pinmux that conflicts with NAND. This will remove
>> that node to avoid such conflicts.
>>
>> Signed-off-by: Tim Harvey <tharvey at gateworks.com>
>> ---
>>  board/gateworks/gw_ventana/gw_ventana.c | 11 +++++++++++
>>  1 file changed, 11 insertions(+)
>>
>> diff --git a/board/gateworks/gw_ventana/gw_ventana.c b/board/gateworks/gw_ventana/gw_ventana.c
>> index 068c726..06611b5 100644
>> --- a/board/gateworks/gw_ventana/gw_ventana.c
>> +++ b/board/gateworks/gw_ventana/gw_ventana.c
>> @@ -1599,6 +1599,17 @@ int ft_board_setup(void *blob, bd_t *bd)
>>                   strlen((const char *)info->model) + 1);
>>
>>       /*
>> +      * disable serial2 node for GW54xx for compatibility with older
>> +      * 3.10.x kernel that improperly had this node enabled in the DT
>> +      */
>
> I understand the issue, but I guess you have a dtb file for your
> (Freescale) 3.10 kernel and another one for kernel mainline. So why this
> issue should be fixed here and not in the related DTS file ?

Stefano,

I only have a single dtb but in this case a customer has an older
kernel with a bug in the dtb and for various reasons required a
bootloader fix (rest of firmware was locked down). In their opinion a
previous bootloader worked (and I never dug in to find out just why...
likely a bootloader bug at the time) and the new one received on newer
boards did not (with their locked down software). I can work around
this in a bootloader script for them if you want to drop this
particular one.

Tim