[U-Boot] Jetson TX2 hangs during dhcp boot

[Stephen Warren]

On 6/14/19 11:09 AM, Andreas Färber wrote:
> Am 14.06.19 um 18:41 schrieb Stephen Warren:
>> On 6/14/19 11:09 AM, Mian Yousaf Kaukab wrote:
>>> Hi,
>>> I am seeing a hang with dhcp boot on Jetson TX2. Its running firmware
>>> from
>>> L4T 32.1 with U-Boot from master branch (c2ea87883e) with [1] applied.
>>>
>>> I use following command sequence at u-boot prompt to boot:
>>>
>>> Tegra186 (P2771-0000-500) # setenv ftdfile tegra186-p2771-0000.dtb
>>> Tegra186 (P2771-0000-500) # setenv boot_targets dhcp
>>> Tegra186 (P2771-0000-500) # boot
>>>
>>> Last thing I see is the following error from TF-A and the board hangs:
>>
>> What is TF-A?
> 
> The artist formerly known as Arm Trusted Firmware.

Ah OK. I had only ever heard that called ATF before.

>>> U-Boot 2019.07-rc4-00137-g6fefd9c475 (Jun 14 2019 - 16:27:34 +0200)
>> ...
>>> TFTP from server xx.xx.xx.xx; our IP address is xx.xx.xx.xx
>>> Filename 'aarch64/grub.efi'.
>>> Load address: 0x80280000
>> ...
>>> MMC: no card present
>>> Scanning disk sdhci at 3400000.blk...
>>> Disk sdhci at 3400000.blk not ready
>>> Scanning disk sdhci at 3460000.blk...
>>> Found 32 disks
>>> copying carveout for
>>> /host1x at 13e00000/display-hub at 15200000/display at 15200000...
>>> copying carveout for
>>> /host1x at 13e00000/display-hub at 15200000/display at 15210000...
>>> copying carveout for
>>> /host1x at 13e00000/display-hub at 15200000/display at 15220000...
>>> ERROR:   ARI request timed out: req 89 on CPU 4
>>> ASSERT: plat/nvidia/tegra/soc/t186/drivers/mce/ari.c <127> : retries
>>> != 0U
>>
>> That file doesn't exist in U-Boot; I guess it's part of grub.efi?
> 
> Looks rather like a TF-A path to me, CC'ing Varun.

Ah yes, I do see that path in our ATF code.

> As Yousaf says above, it's the TF-A you guys ship with latest R32.1.0.
> 
> Maybe the tftpboot operation is overwriting memory used by your TF-A, or

That's pretty unlikely since ATF code/data is in a protected memory 
region that non-secure software can't access.

> differing memory usage is uncovering a missing U-Boot EFI reservation?

Perhaps. I know almost nothing about U-Boot EFI though.

> (I recently wondered whether TX1 may be missing some, as I needed
> multiple tries to boot the kernel successfully there - TF-A 2.1 didn't
> work there, so some more investigations TBD. R28.3.0 still wasn't
> booting U-Boot ~2019.04, I needed R24.2.2 still as you once suggested.)

Hmm. Are you building your own copy of ATF (you mentioned 2.1; I can't 
recall what version we ship)?

FWIW, my usptream U-Boot test system uses L4T r28.1 to test Jetson TX1 
and TX2. It does test DHCP/TFTP, but not EFI or booting a kernel.

Can you provide complete instructions on how to reproduce this issue 
(e.g. which components in L4T you replaced, how to build those 
replacements, how to get/build/use EFI, any config/script/... files you 
used from U-Boot/EFI to trigger the issue above)?

Your best bet is likely to post all this information to the NVIDIA 
Jetson forum so our support people can track the process. I don't expect 
to have much time personally to look at EFI stuff on TX2 right now. Sorry.