From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Andi Kleen <ak@suse.de>, Bernhard Kaindl <bk@suse.de>,
discuss@x86-64.org, linux1394-devel@lists.sourceforge.net,
linux-kernel@vger.kernel.org
Subject: Re: remote debugging via FireWire
Date: Mon, 12 Feb 2007 08:35:38 +1100 [thread overview]
Message-ID: <1171229738.20494.60.camel@localhost.localdomain> (raw)
In-Reply-To: <45CE19F3.2070603@s5r6.in-berlin.de>
On Sat, 2007-02-10 at 20:16 +0100, Stefan Richter wrote:
> [ohci1394_early]
>
> Some remarks to the September 2006 version at
> http://www.suse.de/~bk/firewire/ :
>
> - Seems its .remove won't work properly if more than one OHCI-1394
> controller is installed. And it's .probe isn't reentrant, but that
> might be less of a problem.
> - Its functionality will be lost if there is a FireWire bus reset,
> e.g. when something is plugged in or out. To keep physical DMA
> alive, an interrupt handler had to be installed which writes ~0
> to OHCI1394_PhyReqFilter{Hi,Lo}Set. Can interrupt handlers be
> registered in an early setup stage?
> - There might be some register accesses in the setup which could be
> omitted; I'd have to look this up.
> - Could be optimized to not use ohci1394.h::struct ti_ohci.
> - PCI_CLASS_FIREWIRE_OHCI can be replaced by
> include/linux/pci_ids.h::PCI_CLASS_SERIAL_FIREWIRE_OHCI which
> was newly added in 2.6.20-git#.
> - I suppose .probe should check for PCI_CLASS_SERIAL_FIREWIRE_OHCI
> instead of PCI_CLASS_SERIAL_FIREWIRE.
> - How about dropping support for configuring this as module, to
> simplify the code? Unless this would interfere with ohci1394; and
> it probably would if there was an interrupt handler...
> - "depends on X86_64" is missing in Kconfig.
> - Maybe put it into arch/x86_64/drivers/ instead of drivers/ieee1394?
> - Plus what I mentioned earlier in the thread.
>
> I could send code to address some of this at next weekend or later.
I'd like to have that on ppc as well, so I'd rather keep it in drivers/
I agree that it doesn't need to be a module. If you can load modules,
then you can load the full ohci driver. Thus, if it's an early thingy
initialized by arch, it can export a special "takeover" hook that the
proper ohci module can then call to override it (important if we start
having an irq handler).
Andi, also, how do you deal with iommu ? Not at all ? :-)
Ben.
next prev parent reply other threads:[~2007-02-11 21:36 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-02-10 11:42 What will be in the x86-64/x86 2.6.21 merge Andi Kleen
2007-02-10 13:43 ` [discuss] " Muli Ben-Yehuda
2007-02-10 13:52 ` Andi Kleen
2007-02-10 13:56 ` Muli Ben-Yehuda
2007-02-10 14:03 ` Andi Kleen
2007-02-10 13:51 ` remote debugging via FireWire (was What will be in the x86-64/x86 2.6.21 merge) Stefan Richter
2007-02-10 14:02 ` Andi Kleen
2007-02-10 15:14 ` remote debugging via FireWire Stefan Richter
2007-02-10 15:41 ` Andi Kleen
2007-02-10 19:16 ` Stefan Richter
2007-02-11 21:35 ` Benjamin Herrenschmidt [this message]
2007-02-12 6:49 ` Andi Kleen
2007-02-12 7:29 ` Benjamin Herrenschmidt
2007-12-04 3:45 ` remote debugging via FireWire * __fast__ firedump! Bernhard Kaindl
2007-12-04 7:39 ` Andi Kleen
2007-12-06 16:02 ` Bernhard Kaindl
2007-12-04 22:15 ` Stefan Richter
2007-12-04 22:34 ` Stefan Richter
2007-12-04 22:40 ` Stefan Richter
2007-12-06 18:36 ` [feedback discussion] Early boot debugging via FireWire (ohci1394_dma=early) Bernhard Kaindl
2007-12-06 19:23 ` Stefan Richter
2007-12-06 19:23 ` [PATCH] " Bernhard Kaindl
2007-12-06 20:23 ` Stefan Richter
2007-12-17 13:49 ` Ingo Molnar
2007-12-06 16:32 ` remote debugging via FireWire * __fast__ firedump! Bernhard Kaindl
2007-02-12 14:11 ` What will be in the x86-64/x86 2.6.21 merge James Morris
2007-02-12 14:14 ` Andi Kleen
2007-02-12 14:46 ` James Morris
2007-02-14 6:53 ` Rusty Russell
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=1171229738.20494.60.camel@localhost.localdomain \
--to=benh@kernel.crashing.org \
--cc=ak@suse.de \
--cc=bk@suse.de \
--cc=discuss@x86-64.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux1394-devel@lists.sourceforge.net \
--cc=stefanr@s5r6.in-berlin.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).