[PATCH 07/11] env: Enable SPI flash env for rockchip

[Soeren Moch]

Hi!

On 27.12.19 07:50, Jagan Teki wrote:
> Hi Kever,
>
> On Mon, Dec 23, 2019 at 8:04 AM Kever Yang <kever.yang at rock-chips.com> wrote:
>>
>> Jagan,
>>
>>
>> On 2019/12/21 下午3:54, Jagan Teki wrote:
>>> Most of the SPI flash devices in rockchip are 16MiB size.
>>>
>>> So, keeping U-Boot proper offset start from 128MiB with 1MiB
>>> size and then start env of 8KiB would be a compatible location
>>> between all variants of flash sizes.
>>>
>>> This patch add env start from 0x14000 with a size of 8KiB.
>>
>> What's the space map in SPI flash suppose to be? Including
>> tpl/spl/u-boot.itb
>>
>> I would prefer to use 128KiB-8KiB as the env start address, we'd better
>> to avoid the
>>
>> risk of overlap between the env space and the firmware space.
>
> Here is the 16MiB flash layout, I have used. I can see the loader1
> (tpl/spl) can be possible to load at 0x0 or 0x32K so I have given the
> space for it. and 8K env after loader2(u-boot). let me know your
> thoughts?

Why we cannot use the same layout as what is defined for SD/eMMC:
http://opensource.rock-chips.com/wiki_Partitions



>
>           0x0 - 0x8000,       32K  =>  reserved/loader1
>     0x8000 - 0x40000,    224K =>  loader1
>   0x40000 - 0x140000,    1M  =>  loader2
> 0x140000 - 0x142000,    8K  =>   env
> 0x142000 - 0x842000,    7M  =>  kernel
> 0x842000 - 0x853800,  100K =>  dtb
> 0x853800 -                             =>  root

These small loader1/loader2 partitions may byte us later when newer
u-boot versions only will fit for SD and not for SPI anymore.

The reserved space for kernel is already too small for normal kernel
builds today, not to mention a root filesystem.

Are there any use cases where somebody needs to place boot and root
partitions on SPI flash?

Regards,
Soeren