imx8m(n): garbage on serial line

imx8m(n): garbage on serial line

[Heiko Thiery]

Hi,

I just rebased my pending patch for adding support for the NXP imx8mn
ddr3l evk board. When applying on the current master I see some
garbage on the serial input.

Can anyone confirm that behavior or is it just here?

U-Boot 2022.07-rc4-00011-gacd4e97ae6 (Jun 10 2022 - 09:46:24 +0200)

CPU:   Freescale i.MX8MNano UltraLite Quad rev1.0 at 1200 MHz
Reset cause: WDOG
Model: NXP i.MX8MNano DDR3L EVK board
DRAM:  1 GiB
Core:  140 devices, 18 uclasses, devicetree: separate
WDT:   Started watchdog@30280000 with servicing (60s timeout)
MMC:   FSL_SDHC: 1, FSL_SDHC: 2
Loading Environment from MMC... OK
In:    serial
Out:   serial
Err:   serial
Net:   eth0: ethernet@30be0000
Hit any key to stop autoboot:  0
u-boot=> [25;88R
Unknown command '[25' - try 'help'
Unknown command '88R' - try 'help'
u-boot=>
Unknown command '[25' - try 'help'
Unknown command '88R' - try 'help'
u-boot=>

Thanks
-- 
Heiko

Re: imx8m(n): garbage on serial line

[Fabio Estevam]

Hi Heiko,

On Fri, Jun 10, 2022 at 7:29 AM Heiko Thiery <heiko.thiery@gmail.com> wrote:
>
> Hi,
>
> I just rebased my pending patch for adding support for the NXP imx8mn
> ddr3l evk board. When applying on the current master I see some
> garbage on the serial input.
>
> Can anyone confirm that behavior or is it just here?
>
> U-Boot 2022.07-rc4-00011-gacd4e97ae6 (Jun 10 2022 - 09:46:24 +0200)
>
> CPU:   Freescale i.MX8MNano UltraLite Quad rev1.0 at 1200 MHz
> Reset cause: WDOG
> Model: NXP i.MX8MNano DDR3L EVK board
> DRAM:  1 GiB
> Core:  140 devices, 18 uclasses, devicetree: separate
> WDT:   Started watchdog@30280000 with servicing (60s timeout)
> MMC:   FSL_SDHC: 1, FSL_SDHC: 2
> Loading Environment from MMC... OK
> In:    serial
> Out:   serial
> Err:   serial
> Net:   eth0: ethernet@30be0000
> Hit any key to stop autoboot:  0
> u-boot=> [25;88R
> Unknown command '[25' - try 'help'
> Unknown command '88R' - try 'help'
> u-boot=>
> Unknown command '[25' - try 'help'
> Unknown command '88R' - try 'help'
> u-boot=>

Yes,  I see the same on the Kontron i.MX8MM N801X S board:

U-Boot 2022.07-rc3 (Jun 07 2022 - 22:29:02 +0000)

CPU:   Freescale i.MX8MMQ rev1.0 1600 MHz (running at 1200 MHz)
CPU:   Industrial temperature grade (-40C to 105C) at 50C
Reset cause: POR
Model: Kontron i.MX8MM N801X S
DRAM:  4 GiB
Core:  177 devices, 27 uclasses, devicetree: separate
WDT:   Not starting watchdog@30280000
MMC:   FSL_SDHC: 0, FSL_SDHC: 1
Loading Environment from MMC... OK
In:    serial
Out:   serial
Err:   serial
SEC0:  RNG instantiated
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'

I haven't had a chance to debug/bisect it yet.

Regards,

Fabio Estevam

Re: imx8m(n): garbage on serial line

[Fabio Estevam]

Hi Heiko,

On Fri, Jun 10, 2022 at 7:29 AM Heiko Thiery <heiko.thiery@gmail.com> wrote:
>
> Hi,
>
> I just rebased my pending patch for adding support for the NXP imx8mn
> ddr3l evk board. When applying on the current master I see some
> garbage on the serial input.
>
> Can anyone confirm that behavior or is it just here?

Just tried booting on a imx8mn ddr4 evk and such a problem does not happen:

U-Boot SPL 2022.07-rc4-00007-g57bd363de7 (Jun 10 2022 - 09:42:49 -0300)
SEC0:  RNG instantiated
Normal Boot
WDT:   Started watchdog@30280000 with servicing (60s timeout)
Trying to boot from BOOTROM
image offset 0x8000, pagesize 0x200, ivt offset 0x0
NOTICE:  BL31: v2.7(release):v2.7.0
NOTICE:  BL31: Built : 09:42:28, Jun 10 2022


U-Boot 2022.07-rc4-00007-g57bd363de7 (Jun 10 2022 - 09:42:49 -0300)

CPU:   Freescale i.MX8MNano Quad rev1.0 at 1200 MHz
Reset cause: POR
Model: NXP i.MX8MNano DDR4 EVK board
DRAM:  2 GiB
Core:  139 devices, 22 uclasses, devicetree: separate
WDT:   Started watchdog@30280000 with servicing (60s timeout)
MMC:   FSL_SDHC: 1, FSL_SDHC: 2
Loading Environment from MMC... OK
In:    serial@30890000
Out:   serial@30890000
Err:   serial@30890000
Net:   eth0: ethernet@30be0000
Hit any key to stop autoboot:  0

Also tried booting on a imx8mm evk and did not see the serial garbage either.

Not sure why this happens on the imx8mn ddr3 evk and on the
kontron_sl_imx8mm though.

None of the boards I have physical access show the problem. The
Kontron board  have remote access only,
so not very easy to run git bisect.

Are you able to bisect it with the kontron_sl_imx8mm board?

Re: imx8m(n): garbage on serial line

[Heiko Thiery]

Hi,

Am Fr., 10. Juni 2022 um 15:00 Uhr schrieb Fabio Estevam <festevam@gmail.com>:
>
> Hi Heiko,
>
> On Fri, Jun 10, 2022 at 7:29 AM Heiko Thiery <heiko.thiery@gmail.com> wrote:
> >
> > Hi,
> >
> > I just rebased my pending patch for adding support for the NXP imx8mn
> > ddr3l evk board. When applying on the current master I see some
> > garbage on the serial input.
> >
> > Can anyone confirm that behavior or is it just here?
>
> Just tried booting on a imx8mn ddr4 evk and such a problem does not happen:
>
> U-Boot SPL 2022.07-rc4-00007-g57bd363de7 (Jun 10 2022 - 09:42:49 -0300)
> SEC0:  RNG instantiated
> Normal Boot
> WDT:   Started watchdog@30280000 with servicing (60s timeout)
> Trying to boot from BOOTROM
> image offset 0x8000, pagesize 0x200, ivt offset 0x0
> NOTICE:  BL31: v2.7(release):v2.7.0
> NOTICE:  BL31: Built : 09:42:28, Jun 10 2022
>
>
> U-Boot 2022.07-rc4-00007-g57bd363de7 (Jun 10 2022 - 09:42:49 -0300)
>
> CPU:   Freescale i.MX8MNano Quad rev1.0 at 1200 MHz
> Reset cause: POR
> Model: NXP i.MX8MNano DDR4 EVK board
> DRAM:  2 GiB
> Core:  139 devices, 22 uclasses, devicetree: separate
> WDT:   Started watchdog@30280000 with servicing (60s timeout)
> MMC:   FSL_SDHC: 1, FSL_SDHC: 2
> Loading Environment from MMC... OK
> In:    serial@30890000
> Out:   serial@30890000
> Err:   serial@30890000
> Net:   eth0: ethernet@30be0000
> Hit any key to stop autoboot:  0
>
> Also tried booting on a imx8mm evk and did not see the serial garbage either.
>
> Not sure why this happens on the imx8mn ddr3 evk and on the
> kontron_sl_imx8mm though.

Yes, this is strange.

>
> None of the boards I have physical access show the problem. The
> Kontron board  have remote access only,
> so not very easy to run git bisect.
>
> Are you able to bisect it with the kontron_sl_imx8mm board?

Unfortunately only next week again. But I will try on my imx8mq later.

--
Heiko

Re: imx8m(n): garbage on serial line

[Heiko Thiery]

Hi Fabio,

Am Fr., 10. Juni 2022 um 16:13 Uhr schrieb Heiko Thiery
<heiko.thiery@gmail.com>:
>
> Hi,
>
> Am Fr., 10. Juni 2022 um 15:00 Uhr schrieb Fabio Estevam <festevam@gmail.com>:
> >
> > Hi Heiko,
> >
> > On Fri, Jun 10, 2022 at 7:29 AM Heiko Thiery <heiko.thiery@gmail.com> wrote:
> > >
> > > Hi,
> > >
> > > I just rebased my pending patch for adding support for the NXP imx8mn
> > > ddr3l evk board. When applying on the current master I see some
> > > garbage on the serial input.
> > >
> > > Can anyone confirm that behavior or is it just here?
> >
> > Just tried booting on a imx8mn ddr4 evk and such a problem does not happen:
> >
> > U-Boot SPL 2022.07-rc4-00007-g57bd363de7 (Jun 10 2022 - 09:42:49 -0300)
> > SEC0:  RNG instantiated
> > Normal Boot
> > WDT:   Started watchdog@30280000 with servicing (60s timeout)
> > Trying to boot from BOOTROM
> > image offset 0x8000, pagesize 0x200, ivt offset 0x0
> > NOTICE:  BL31: v2.7(release):v2.7.0
> > NOTICE:  BL31: Built : 09:42:28, Jun 10 2022
> >
> >
> > U-Boot 2022.07-rc4-00007-g57bd363de7 (Jun 10 2022 - 09:42:49 -0300)
> >
> > CPU:   Freescale i.MX8MNano Quad rev1.0 at 1200 MHz
> > Reset cause: POR
> > Model: NXP i.MX8MNano DDR4 EVK board
> > DRAM:  2 GiB
> > Core:  139 devices, 22 uclasses, devicetree: separate
> > WDT:   Started watchdog@30280000 with servicing (60s timeout)
> > MMC:   FSL_SDHC: 1, FSL_SDHC: 2
> > Loading Environment from MMC... OK
> > In:    serial@30890000
> > Out:   serial@30890000
> > Err:   serial@30890000
> > Net:   eth0: ethernet@30be0000
> > Hit any key to stop autoboot:  0
> >
> > Also tried booting on a imx8mm evk and did not see the serial garbage either.
> >
> > Not sure why this happens on the imx8mn ddr3 evk and on the
> > kontron_sl_imx8mm though.
>
> Yes, this is strange.
>
> >
> > None of the boards I have physical access show the problem. The
> > Kontron board  have remote access only,
> > so not very easy to run git bisect.
> >
> > Are you able to bisect it with the kontron_sl_imx8mm board?
>
> Unfortunately only next week again. But I will try on my imx8mq later.

It took me some effort to get the current u-boot running on my imx8mq.
But finally it works and I do not see this garbage on the imx8mq. Next
week I will check on the kontron_sl_imx8mm.

> --
> Heiko

Re: imx8m(n): garbage on serial line

[Fabio Estevam]

Hi Heiko,

On Sat, Jun 11, 2022 at 3:12 AM Heiko Thiery <heiko.thiery@gmail.com> wrote:

> It took me some effort to get the current u-boot running on my imx8mq.
> But finally it works and I do not see this garbage on the imx8mq. Next
> week I will check on the kontron_sl_imx8mm.

Thanks, appreciated it!

Re: imx8m(n): garbage on serial line

[Heiko Thiery]

Hi Fabio,


Am Sa., 11. Juni 2022 um 13:10 Uhr schrieb Fabio Estevam <festevam@gmail.com>:
>
> Hi Heiko,
>
> On Sat, Jun 11, 2022 at 3:12 AM Heiko Thiery <heiko.thiery@gmail.com> wrote:
>
> > It took me some effort to get the current u-boot running on my imx8mq.
> > But finally it works and I do not see this garbage on the imx8mq. Next
> > week I will check on the kontron_sl_imx8mm.


This is the output on the kontron bl-imx8m board:

U-Boot SPL 2022.07-rc4-00007-g8c3f838be2 (Jun 13 2022 - 15:36:08 +0200)
Kontron SL i.MX8MM (N801X) module, 1 GB RAM detected
Touch controller detected, assuming LVDS panel...
Normal Boot
WDT:   Not starting watchdog@30280000
Trying to boot from MMC2
NOTICE:  BL31: v2.4(release):v2.4
NOTICE:  BL31: Built : 15:09:24, Sep 10 2021


U-Boot 2022.07-rc4-00007-g8c3f838be2 (Jun 13 2022 - 15:36:08 +0200)

CPU:   Freescale i.MX8MMQ rev1.0 1600 MHz (running at 1200 MHz)
CPU:   Industrial temperature grade (-40C to 105C) at 46C
Reset cause: POR
Model: Kontron i.MX8MM N801X S LVDS
DRAM:  1 GiB
Core:  178 devices, 25 uclasses, devicetree: separate
WDT:   Not starting watchdog@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
=>



Here I cannot see the extra serial-in garbage ;-/

>
> Thanks, appreciated it!

-- 
Heiko

Re: imx8m(n): garbage on serial line

[Fabio Estevam]

Hi Heiko,

On Mon, Jun 13, 2022 at 10:54 AM Heiko Thiery <heiko.thiery@gmail.com> wrote:

> This is the output on the kontron bl-imx8m board:
>
> U-Boot SPL 2022.07-rc4-00007-g8c3f838be2 (Jun 13 2022 - 15:36:08 +0200)
> Kontron SL i.MX8MM (N801X) module, 1 GB RAM detected
> Touch controller detected, assuming LVDS panel...
> Normal Boot
> WDT:   Not starting watchdog@30280000
> Trying to boot from MMC2
> NOTICE:  BL31: v2.4(release):v2.4

Just tried with the same v2.4 TF-A version:

U-Boot SPL 2022.07-rc4-00007-g57bd363de7 (Jun 13 2022 - 11:18:10 -0300)
Kontron SL i.MX8MM (N801X) module, 4 GB RAM detected
Normal Boot
WDT:   Not starting watchdog@30280000
Trying to boot from MMC1
NOTICE:  BL31: v2.4(release):v2.4
NOTICE:  BL31: Built : 11:17:34, Jun 13 2022


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@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.

My version has 4GiB of RAM, yours has only 1GiB.

Could this make a difference?

Thanks

Re: imx8m(n): garbage on serial line

[Heiko Thiery]

Hi Fabio,

Am Mo., 13. Juni 2022 um 16:27 Uhr schrieb Fabio Estevam <festevam@gmail.com>:
>
> Hi Heiko,
>
> On Mon, Jun 13, 2022 at 10:54 AM Heiko Thiery <heiko.thiery@gmail.com> wrote:
>
> > This is the output on the kontron bl-imx8m board:
> >
> > U-Boot SPL 2022.07-rc4-00007-g8c3f838be2 (Jun 13 2022 - 15:36:08 +0200)
> > Kontron SL i.MX8MM (N801X) module, 1 GB RAM detected
> > Touch controller detected, assuming LVDS panel...
> > Normal Boot
> > WDT:   Not starting watchdog@30280000
> > Trying to boot from MMC2
> > NOTICE:  BL31: v2.4(release):v2.4
>
> Just tried with the same v2.4 TF-A version:
>
> U-Boot SPL 2022.07-rc4-00007-g57bd363de7 (Jun 13 2022 - 11:18:10 -0300)
> Kontron SL i.MX8MM (N801X) module, 4 GB RAM detected
> Normal Boot
> WDT:   Not starting watchdog@30280000
> Trying to boot from MMC1
> NOTICE:  BL31: v2.4(release):v2.4
> NOTICE:  BL31: Built : 11:17:34, Jun 13 2022
>
>
> 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@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.
>
> My version has 4GiB of RAM, yours has only 1GiB.
>
> Could this make a difference?


I can hardly imagine it. I don't have an explanation for it.

>
> Thanks

Re: imx8m(n): garbage on serial line

[Fabio Estevam]

On Mon, Jun 13, 2022 at 11:27 AM Fabio Estevam <festevam@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@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@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@linaro.org>

Akashi-san, any ideas?

Re: imx8m(n): garbage on serial line

[Fabio Estevam]

Hi Heiko,

On Fri, Jun 10, 2022 at 7:29 AM Heiko Thiery <heiko.thiery@gmail.com> wrote:

> Hit any key to stop autoboot:  0
> u-boot=> [25;88R
> Unknown command '[25' - try 'help'
> Unknown command '88R' - try 'help'

git bisect points me to an efi loader commit as the guilty one.

Can you please pass the line below into your imx8mn ddr3l evk board defconfig?

# CONFIG_EFI_LOADER is not set

Do you see serial console garbage in this case?

Just wanted to confirm if the error we are seeing is due to the efi
loader breakage.

Re: imx8m(n): garbage on serial line

[Heiko Thiery]

Hi Fabio,

Am Mo., 13. Juni 2022 um 19:01 Uhr schrieb Fabio Estevam <festevam@gmail.com>:
>
> Hi Heiko,
>
> On Fri, Jun 10, 2022 at 7:29 AM Heiko Thiery <heiko.thiery@gmail.com> wrote:
>
> > Hit any key to stop autoboot:  0
> > u-boot=> [25;88R
> > Unknown command '[25' - try 'help'
> > Unknown command '88R' - try 'help'
>
> git bisect points me to an efi loader commit as the guilty one.
>
> Can you please pass the line below into your imx8mn ddr3l evk board defconfig?
>
> # CONFIG_EFI_LOADER is not set
>
> Do you see serial console garbage in this case?
>
> Just wanted to confirm if the error we are seeing is due to the efi
> loader breakage.

I can confirm that by disabling EFI loader the error is gone.


--
Heiko