[U-Boot] [PATCH 2/9] sunxi: Move SPL s_init() code to board_init_f()

[Simon Glass]

Hi,

On 2 February 2015 at 01:07, Hans de Goede <hdegoede at redhat.com> wrote:
> Hi Simon, Siarhei,
>
> On 01-02-15 21:59, Simon Glass wrote:
>>
>> Hi Siarhei,
>>
>> On 1 February 2015 at 11:37, Siarhei Siamashka
>> <siarhei.siamashka at gmail.com>
>
>
> <snip>
>
>>> A comprehensive FEL usage guide is supposed to be in the linux-sunxi
>>> wiki. But it might be not very up to date with the mainline u-boot
>>> usage.
>>>
>>> Anyway, first just clone the https://github.com/linux-sunxi/sunxi-tools
>>> repository and build it. This will provide you with the x86 binary of
>>> the 'fel' tool, which is used on your desktop PC to talk with the
>>> device.
>>>
>>> Then connect the device to your PC using a "USB A to USB mini/micro B"
>>> cable. And reset the board while keeping the "FEL" button pressed. The
>>> button might be labelled as "UPGRADE" on your pcduino3 board:
>>> http://linux-sunxi.org/LinkSprite_pcDuino_V3#FEL_mode
>>>
>>> Then just run "fel ver" command:
>>> http://linux-sunxi.org/FEL#Running_the_fel_tool
>>>
>>> If everything is fine, it should respond with something like this:
>>> AWUSBFEX soc=00162500(A13) 00000001 ver=0001 44 08 scratchpad=00007e00
>>> 00000000 00000000
>>>
>>> Now you can use "write" commands to upload data to SRAM. And "exe"
>>> command to execute functions on the device (works as some kind of RPC):
>>> http://linux-sunxi.org/FEL/USBBoot#Manual_loading
>>>
>>> As a simple test, you can upload just a single "bx lr" instruction
>>> (compiled in ARM mode) to the address 0x2000 and try to execute it.
>>> In the case if your code screws up something and does not return
>>> control to the BROM correctly, then the "fel" tool can't communicate
>>> over USB anymore and just timeouts. Regarding the address space, you
>>> can use SRAM addresses starting from 0x2000 up to something like 0x5E00
>>> (that's where the stack pointer is set). This was a description of a
>>> "bare metal" FEL usage.
>>>
>>> Now as for the u-boot support. You can compile and run u-boot in the FEL
>>> mode configuration on pcduino3 in the following way:
>>>
>>> make CROSS_COMPILE=arm-none-gnueabi- Linksprite_pcDuino3_felconfig
>>> make CROSS_COMPILE=arm-none-gnueabi- -j2
>>>
>>> fel write 0x2000 spl/u-boot-spl.bin
>>> fel exe 0x2000
>>>
>>> sleep 1 # Wait for DRAM initialization to complete
>>
>>
>> i.e. wait for U-Boot SPL to return to the BROM?
>>
>>>
>>> fel write 0x4a000000 u-boot.bin
>>> fel exe 0x4a000000
>>>
>>> Please note the use of '*_felconfig' instead of '*_defconfig'.
>>> And also right now the FEL mode support is broken. That's why the
>>> http://lists.denx.de/pipermail/u-boot/2015-January/203282.html
>>> patchset tried to address this problem.
>>>
>>
>> OK that looks like an excellent guide, thank you. I will make some time to
>> take a more detailed look at this as soon as I can, but definitely in the
>> next few days.
>
>
> I've been reading all threads on this, thank you both for looking into this,
> since you're on it I'm going to leave this be (and not review / apply
> Siarhei's patches for this), and we can revisit this later, with hopefully a
> better fix.

Thanks to Siarhei's instructions I have a working setup with pcduino3.
One less board where I have to swap SD cards. Can I suggest that it
would be really nice to have a README.sunxi that covers all of this?

Anyway I will fiddle around and see what I can come up with.

Regards,
Simon