[U-Boot] [PATCH 12/12] imx: ventana: switch to SPL

[York Sun]

On 05/07/2014 01:35 PM, Tim Harvey wrote:
> On Wed, May 7, 2014 at 1:29 PM, York Sun <yorksun at freescale.com> wrote:
>> On 05/07/2014 01:27 PM, Tim Harvey wrote:
>>> On Wed, May 7, 2014 at 9:14 AM, York Sun <yorksun at freescale.com> wrote:
>>>> On 05/06/2014 04:35 PM, Tim Harvey wrote:
>>>>> On Tue, May 6, 2014 at 12:11 PM, Jeroen Hofstee <dasuboot at myspectrum.nl> wrote:
>>>>>> Hello Tim,
>>>>>>
>>>> <snip>
>>>>>>
>>>>>> Since Crt0.S already created gd on the stack before calling
>>>>>> board_init_f, can't the assignment of gd not simply be removed?
>>>>>> Is there anything special about gdata?
>>>>>>
>>>>>> Regards,
>>>>>> Jeroen
>>>>>>
>>>>>>
>>>>>
>>>>> Jeroen,
>>>>>
>>>>> That does make sense, but what I find is that York's ocmmit
>>>>> dec1861be90c948ea9fb771927d3d26a994d2e20 requires that gd be blanked
>>>>> and its not. This causes bus_i2c_init to skip its initialization
>>>>> because p->base is not zero.
>>>>>
>>>>> York, does this make sense? Your patch creates a dependence on
>>>>> gd->srdata being blank which isn't the case with the SRAM when booting
>>>>> from the IMX6 boot rom.
>>>>>
>>>>
>>>> GD should be cleared (zeroed). Then we don't have this problem. Whoever sets up
>>>> gd (board_int_f, cpu_init_f, or others) should make sure gd is cleared. Why
>>>> isn't it the case for IMX6 boot rom?
>>>>
>>>> York
>>>>
>>>
>>> York,
>>>
>>> crt0.S is mapping gd to where the SPL stack pointer is defined, which
>>> is where Freescale says its stack pointer is for its firmware BOOT
>>> ROM, so its initial data will be dependent on what the BOOT ROM did.
>>>
>>> I think the right solution is to have crt0.S zero it out.
>>>
>>
>> Either crt0.S, or somewhere before gd is used for the first time. Can it be done
>> in board_init_f()?
>>
>> York
>>
>>
> 
> It makes more sense to do it in crt0.S so that all boards don't have
> to do it and can make the assumption that it is cleared.
> 

No objection as far as it is cleared.

York