Re: Boot from USB on RPi4 8GB?

From: Mark Millard via freebsd-arm <freebsd-arm_at_freebsd.org>
Date: Sun, 30 May 2021 20:28:33 UTC

On 2021-May-30, at 10:59, William Carson via freebsd-arm <freebsd-arm at freebsd.org> wrote:

Thank you for the quick and thorough reply!

>> . . .
> 
>> What does:
>> 
>> # rpi-eeprom-config 
>> [all]
>> BOOT_UART=0
>> WAKE_ON_GPIO=1
>> POWER_OFF_ON_HALT=0
>> DHCP_TIMEOUT=45000
>> DHCP_REQ_TIMEOUT=4000
>> TFTP_FILE_TIMEOUT=30000
>> ENABLE_SELF_UPDATE=1
>> DISABLE_HDMI=0
>> BOOT_ORDER=0xf41
>> 
>> report in your context? (An equivalent command is
>> "vcgencmd bootloader_config". I show example output
>> above.)
> 
> root@raspberrypi:~# rpi-eeprom-config
> [all]
> BOOT_UART=0
> WAKE_ON_GPIO=1
> POWER_OFF_ON_HALT=0
> 

That looks like an old default is still in place.

What my output showed is the modern default they ship
with as I understand. You may want to update.

If you want more debug output from the RPi4B firmware,
you could use:

BOOT_UART=1

I normally do. I've just not gotten around to updating
that specific device yet. That goes along with using:

enable_uart=1
uart_2ndstage=1
dtdebug=1

in config.txt . I use dtoverlay=disable-bt in config.txt
which causes the better UART to be used for the serial
console. There is also the alternative:
dtoverlay=miniuart-bt

The (or an) explicit BOOT_ORDER in rpi-eeprom-config
might be appropriate as well. I saw no reason to change
or eliminate the others and left them in place on the
other RPi4B's.

https://www.raspberrypi.org/documentation/configuration/config-txt/boot.md

lists the following for config.txt use:

bootcode_delay (default 0, so 0 sec)
boot_delay (default 1, so 1 sec)
boot_delay_ms (default 0, so 0 msec)

It also has notes about uart_2ndstage use and the like.
I've never had to use these but if your device takes a
while to become ready, thse might be able to help.

===
Mark Millard
marklmi at yahoo.com
( dsl-only.net went
away in early 2018-Mar)