u-boot | u-boot on the Nintendo Switch

Hi, I was trying to make network work on qemu-system-arm uboot for tftp/dhcp booting , Could not understand QEMU 5.0.0 networking configuration needed , can you help on this.

$qemu-system-arm --version QEMU emulator version 5.0.0

Yocto BSP used: https://github.com/ahmedkassem56/meta-qemuarma9.git

$ cat /etc/qemu-ifup

I maintain a custom Yocto meta layer compatible with Dunfell. It supports a Microchip SAMA5D27 processor based board. I have several bbappend files in this layer that apply only to file from the meta-atmel and other Microchip specific packages.

Now, I want to re-use many parts of this custom meta layer and support a new processor from a different vendor. I have created my own new image recipe in my layer that does not include these bbappend files that are only relevant to Microchip.

The problem is that Yocto throws as error 'No recipes available for' regarding my bbappend files. The error seems to happen during parsing and does not consider whether I use the recipe or not in the current target.

I have searched extensively for a solution, but so far have come up empty. How can I use 1 meta-layer and maintain different bbappend files, while being able to switch MACHINE variables for different target builds? Thanks!

Bitbake Version:

I believe the UBoot binary image has a common format , containing following fields:

Background:

I have an old Seagate BlackArmor NAS 110 that I'm trying to install Debian on by following the instructions here: https://github.com/hn/seagate-blackarmor-nas.

I have a couple of USB to TTL serial adapters (one FTDI chipset and the other Prolific) that I've tried and have run into the same issue with both. I have made the connection to the serial port on the board of the NAS using a multimeter to make sure I've gotten the pinout correct.

Problem:

I'm not able to stop the autoboot process by pressing keys and any point during the boot process. The device also does not seem to respond to any keystrokes although they are echoed back.

What I've Tried So Far:

• Using USB to TTL serial adapters with two different chipsets
• Using the adapters on two different computers (MacBook Pro and a ThinkPad)
• Using different operating systems (MacOS, Windows 10, Ubuntu 20.04)
• Using different terminal programs (Screen, Minicom, Putty)
• Turned off hardware and software flow control
• Tested output of adapters by shorting RX and TX pins and seeing keystrokes echoed back
• Commands seem to be sent to device as when I type I see my commands echoed back (not sure if this is supposed to happen)

I've been at this for a few days and can't figure it out. I've also recorded my screen while experiencing the issue: https://streamable.com/xl43br. Can anyone see where I'm going wrong?

Terminal output while experiencing the problem:

I want to buy the Jetson Tx2 in order to do some deep dive. According to their Docs, the Bootloader at some point executes the C-Boot followed by U-Boot. C-Boot runs with Exception Level (EL) 2, does somebody know whether C-Boot passes EL 2 to U-Boot (or C-Boost passes EL 3 to U-Boot)?

If you have a Tx2 you could simply test it by:

dmesg | grep EL

Thanks in advance!

i'm working on building U-Boot boot loader for raspberry pi 4. i have followed all the documentation instructions and building has finished well, but the results files are the following

I have a MIPS system (VSC7427) with u-boot and I am trying to boot a more recent kernel than the kernel provided by the vendor in their GPL release (which boots just fine).

The kernel FIT image appears to be sane, and judging by the output I think it should be bootable:

I am running Linux kernel 4.14.149 built by Yocto Zeus, and I am running 2019.07 U-boot. At the recommendation of our security team, I am trying to get rid of the Linux console. I am not worried about debugging (once I get this to work anyways); we have other ways of getting the system logs out of the machine, and this will not be done on software development boards. That mechanism is already in place and is tested working. We have an i.MX6 as our core (this is an embedded system), and we have dedicated UART5 to our console on dev boards.

I have tried a few different methods to do this. The first was to disable the framebuffer console kernel config (CONFIG_FRAMEBUFFER_CONSOLE). The primary issue with this approach is that it disabled the splash screen. We have a splash screen that is put up in U-boot (and it is displayed again by Linux), but Linux appears to reset the framebuffer or something when it is booting, resulting in the display flickering and being blank for a bit before our applications start, which was unacceptable (and is the reason we put the splash screen up in both U-boot and Linux).

I also tried just setting "console=" on our command line. This is close to what we want to achieve in that the console doesn't come out the UART anymore, but we see it start to appear on the display on top of the splash screen. I haven't found any way to fix that (I can upload a screenshot if desired).

Just eliminating the console parameter entirely didn't appear to work, it still came out the UART. This is to be expected based on the serial console documentation which says it just uses the first available device.

I have tried commenting out the console initialization in main.c in the Linux source, which exploded rather quickly.

I tried setting to be a netconsole (see Where do you send the kernel console on an embedded system?) but the splash screen still got overwritten, same as the setting it nothing case.

The last thing I have tried was just setting it to a bogus device ("console=ttymxc9" on the Linux command line). While this appears to work (there is no data on the display or the UART) it appears to stall (crash?) partway through bootup and without being able to get the logs (it stalls before our application service runs). I say stall because we have Linux configured for a heartbeat and we do still get proper LED heartbeat behavior. None of the systemd services I added to our build however appear to run (I added one to save the journalctl log file after boot to a file on an external SD card for debugging purposes until I get this working)

At this point, I have run out of ideas on how to get rid of the console while keeping the splash screen intact. What is the proper way to disable the Linux console?

My boot chain is EFI --> U-Boot (as EFI app) --> loading itb file to the ramdisk --> starting kernel. When system ends startup process, and I've checked the /boot directory, I expected to see boot.cfg and image.itb files. I see bzImage file instead. Device architecture is x86_64.

My image content looks like: