linuxppc-dev.lists.ozlabs.org archive mirror
 help / color / mirror / Atom feed
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Felix Radensky <felix@embedded-sol.com>
Cc: linuxppc-dev@ozlabs.org, Stefan Roese <sr@denx.de>,
	Feng Kan <fkan@amcc.com>
Subject: Re: PCI-PCI bridge scanning broken on 460EX
Date: Mon, 11 Jan 2010 08:31:57 +1100	[thread overview]
Message-ID: <1263159117.724.15.camel@pasglop> (raw)
In-Reply-To: <4B4A4307.5050704@embedded-sol.com>


> OK, I'll try writing byte by byte. The funny thing is the u-boot also 
> writes the
> same value to PCI_PRIMARY_BUS register and it doesn't cause reset.

Maybe the bridge doesn't want to be programmed more than once on these
registers ? In any case, that's very very fishy.... I wonder if the
bridge is causing a PCI reset -upstream- (which would really be a weird
thing to do) and the 460 is turning that into a system reset ? Check if
there are ways to control how the 460 reacts to PCI resets...

In any case, it looks like a fucked up bridge to me. I don't suppose
you've seen anything in the bridge data sheet or errata sheet that could
explain what it's doing ?

Cheers,
Ben.

  reply	other threads:[~2010-01-10 21:32 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-12-28 10:51 PCI-PCI bridge scanning broken on 460EX Felix Radensky
2010-01-04  5:55 ` Benjamin Herrenschmidt
2010-01-04  8:59   ` Felix Radensky
2010-01-10 12:56     ` Felix Radensky
2010-01-10 20:38       ` Benjamin Herrenschmidt
2010-01-10 21:13         ` Felix Radensky
2010-01-10 21:31           ` Benjamin Herrenschmidt [this message]
2010-01-11  9:58             ` Stef van Os
2010-01-11 11:48               ` Felix Radensky
2010-01-11 16:46                 ` Felix Radensky
2010-01-11 20:53                   ` Benjamin Herrenschmidt
2010-01-11 22:48                     ` Felix Radensky
2010-01-11 22:53                       ` Benjamin Herrenschmidt
2010-01-12 11:02                         ` Felix Radensky
2010-01-12 11:14                           ` Stef van Os

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1263159117.724.15.camel@pasglop \
    --to=benh@kernel.crashing.org \
    --cc=felix@embedded-sol.com \
    --cc=fkan@amcc.com \
    --cc=linuxppc-dev@ozlabs.org \
    --cc=sr@denx.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).