[U-Boot] of-platdata address map decode for 64-bits

Simon Glass
2017-02-08T05:10:21Z

Hi Kever,

On 4 February 2017 at 16:30, Kever Yang <kever.yang@rock-chips.com> wrote:
> Hi Simon,
>
> For rk3399, the data for sdram driver in dts is big, I don't want to do
> the copy for it,

Are you referring to the call to fdtdec_get_int_array()? Don't you
have heaps of SRAM though? So why does it matter? If you are really
worried about it you could loop through the data word by word instead.
But why?

> so I think use of-platdata is a good method, and for image size, its
> smaller, then it's sooner to load.

Yes it reduces the image size, but only by a small amount. I have not
checked it on ARM64 but it should be around 5KB. I don't think it is
very important.

Regards,
Simon

>
> Thanks,
> - Kever
>
> On 01/26/2017 10:22 PM, Simon Glass wrote:
>>
>> Hi Kever,
>>
>> On 17 January 2017 at 23:37, Kever Yang <kever.yang@rock-chips.com> wrote:
>>>
>>> Hi Simon,
>>>
>>> For my rk3399(64bit) dts, the address is described as below:
>>> #address-cells = <2>;
>>> reg = <0x0 0xfe320000 0x0 0x4000>;
>>>
>>> not like 32-bit soc which reg address describe like:
>>> reg = <0xfe320000 0x4000>;
>>>
>>> There should have some update for this dts decode, right?
>>> like:
>>> map_sysmem()
>>> regmap_init_mem_platdata()
>>>
>>> Do you have a idea to update all these kind of function call?
>>> It will be very great if you can send a patch for it.
>>>
>>> Thanks,
>>> - Kever
>>>
>> Yes I think so.
>>
>> But first I'd like to understand why we need to use of-platdata on
>> this very modern SoC. Can you tell me the maximum SPL size you can
>> support on this SoC? I thought you had removed the 30KB limit?
>>
>> Using of-platdata only saves 3-4KB.
>>
>> Regards,
>> Simon
>>
>>
>>
>
>