[U-Boot] [PATCH] imx_common: check for Serial Downloader in spl_boot_device

[Stefan Roese <sr@denx.de>]

Hi Stefano,

On 04.12.2015 12:49, Stefano Babic wrote:
> On 04/12/2015 11:51, Fabio Estevam wrote:
>> Hi Stefano,
>>
>> On Fri, Dec 4, 2015 at 7:02 AM, Stefano Babic <sbabic@denx.de> wrote:
>>> Check for bmode before reading the boot device
>>> to check if a serial downloader is started,
>>> and returns UART if the serial downloader is set,
>>> letting SPL to wait for an image if
>>> CONFIG_SPL_YMODEM_SUPPORT is set.
>>>
>>> This allows to load again a SPL based board
>>> with imx_usb_loader together with a tool
>>> such as kermit.
>>
>> Just curious: what were the commands you usned with imx_usb_loader to
>> load SPL + u-boot.img?
>>
>
> I did in this way:
>
> sudo ../imx_usb_loader/imx_usb -v SPL
> kermit kermit_uboot
>
> And kermit_uboot (a kermit script) contains the lines:
>
> set line /dev/ttyUSB1
> set speed 115200
> SET CARRIER-WATCH OFF
> set flow-control none
> set handshake none
> set prefixing all
> set file type bin
> set protocol ymodem
> send u-boot.img
> c
>
> The last "c" command tells kermit (from ckermit package in most distro)
> to switch from command line mode to communication mode, and when the
> script is finished, I get U-Boot prompt in the same shell. I tested on a
> custom board booting from SPI (when internal mode is used), and changing
> BOOT_MODE to serial, SPL starts automatically a download with y-modem.

Could you please add this description to some imx README in the
U-Boot source tree? I'm pretty sure this could be helpful to others
as well.

Thanks,
Stefan