Path: news.eternal-september.org!eternal-september.org!feeder3.eternal-september.org!nntp-feed.chiark.greenend.org.uk!ewrotcd!.POSTED.chiark.greenend.org.uk!not-for-mail
From: Theo <theom+news@chiark.greenend.org.uk>
Newsgroups: comp.sys.raspberry-pi
Subject: Re: Pi2 bootcode.bin puzzle
Date: 25 Mar 2025 16:49:41 +0000 (GMT)
Organization: University of Cambridge, England
Message-ID: <buh*PEl+z@news.chiark.greenend.org.uk>
References: <vrufnd$3hlnn$1@dont-email.me>
Injection-Info: chiark.greenend.org.uk; posting-host="chiark.greenend.org.uk:93.93.131.173";
	logging-data="19695"; mail-complaints-to="abuse@chiark.greenend.org.uk"
User-Agent: tin/1.8.3-20070201 ("Scotasay") (UNIX) (Linux/5.10.0-28-amd64 (x86_64))
Originator: theom@chiark.greenend.org.uk ([93.93.131.173])

bp@www.zefox.net wrote:
> Can bootcode.bin pick up any parameters (other than noting the
> presence of a timeout file) from any files placed on the microSD?

No idea, but one problem I've had in the past is that USB devices can take a
while to initialise, and it varies quite a bit between devices.  This could
be a reason why boots will sometimes fail - especially with eg spinning HDD.

Often it was necessary to add an explicit delay so that system didn't try to
read them before they were ready.  I think on Linux the kernel cmdline
options were 'rootwait' and 'rootdelay' but I don't know if bootcode.bin has
any kind of setting like that.

Theo