imx8m(n): garbage on serial line

[Fabio Estevam]

On Mon, Jun 13, 2022 at 11:27 AM Fabio Estevam <festevam at gmail.com> wrote:

> U-Boot 2022.07-rc4-00007-g57bd363de7 (Jun 13 2022 - 11:18:10 -0300)
>
> CPU:   Freescale i.MX8MMQ rev1.0 1600 MHz (running at 1200 MHz)
> CPU:   Industrial temperature grade (-40C to 105C) at 60C
> Reset cause: POR
> Model: Kontron i.MX8MM N801X S
> DRAM:  4 GiB
> Core:  175 devices, 25 uclasses, devicetree: separate
> WDT:   Not starting watchdog at 30280000
> MMC:   FSL_SDHC: 0, FSL_SDHC: 1
> Loading Environment from SPIFlash... SF: Detected mx25r1635f with page
> size 256 Bytes, erase size 64 KiB, total 2 MiB
> OK
> In:    serial
> Out:   serial
> Err:   serial
> Net:   Could not get PHY for FEC0: addr 0
> No ethernet found.
>
> Hit any key to stop autoboot:  0
> => [55;203R
> Unknown command '[55' - try 'help'
> Unknown command '203R' - try 'help'
>
> and the serial garbage is seen.

I managed to bisect it, and the serial console garbage is caused by:

commit a9bf024b2933bba0e23038892970a18b72dfaeb4
Author: AKASHI Takahiro <takahiro.akashi at linaro.org>
Date:   Tue Apr 19 10:05:12 2022 +0900

    efi_loader: disk: a helper function to create efi_disk objects from udevice

    Add efi_disk_probe() function.
    This function creates an efi_disk object for a raw disk device (UCLASS_BLK)
    and additional objects for related partitions (UCLASS_PARTITION).

    So this function is expected to be called through driver model's "probe"
    interface every time one raw disk device is detected and activated.
    We assume that partition devices (UCLASS_PARTITION) have been created
    when this function is invoked.

    Signed-off-by: AKASHI Takahiro <takahiro.akashi at linaro.org>

Akashi-san, any ideas?