From: Anton Vorontsov <avorontsov@ru.mvista.com>
To: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Ingo Molnar <mingo@elte.hu>,
linux-ide@vger.kernel.org,
Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>,
Alan Cox <alan@lxorguk.ukuu.org.uk>,
linux-kernel@vger.kernel.org,
Thomas Gleixner <tglx@linutronix.de>,
Steven Rostedt <rostedt@goodmis.org>,
Daniel Walker <dwalker@mvista.com>
Subject: Re: [PATCH v2 -rt] ide: workaround buggy hardware issues with preemptable hardirqs
Date: Sat, 28 Jun 2008 15:31:26 +0400 [thread overview]
Message-ID: <20080628113126.GA438@polina.dev.rtsoft.ru> (raw)
In-Reply-To: <486612CC.3060505@ru.mvista.com>
On Sat, Jun 28, 2008 at 02:30:36PM +0400, Sergei Shtylyov wrote:
> Hello.
>
> Anton Vorontsov wrote:
>> IDE interrupt handler relies on the fact that, if necessary, hardirqs
>> will re-trigger on ISR exit. The assumption is valid for level sensitive
>> interrupts.
>>
>
> It's valid for both edge and level triggered interrupts.
I think this is depends on PIC, whether it can or can not detect masked
edge interrupts...
>> But some hardware (namely ULi M5228 in the ULi M1575 "Super South Brige")
>> behaves in a strange way: it asserts interrupts as edge sensitive. And
>> because preemptable IRQ handler disables PIC's interrupt, PIC will likely
>> miss it.
>>
>
> Unmasking an IRQ should re-enable an edge detector in a PIC (or that
> detector should even be independent from mask).
Should? Hm.. well, I can easily check it. Will just program the MPIC IRQ
to edge sensitive, and see if it fixes the problem (not sure if I already
tried this, I think I did try).
--
Anton Vorontsov
email: cbouatmailru@gmail.com
irc://irc.freenode.net/bd2
next prev parent reply other threads:[~2008-06-28 11:31 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-06-23 23:40 [PATCH -rt] ide: fix interrupts processing issue with preempt-able hardirqs Anton Vorontsov
2008-06-23 23:51 ` Ingo Molnar
2008-06-24 0:00 ` Anton Vorontsov
2008-06-25 12:34 ` Anton Vorontsov
2008-06-25 12:32 ` Alan Cox
2008-06-25 14:12 ` Anton Vorontsov
2008-06-25 13:15 ` Sergei Shtylyov
2008-06-25 14:22 ` Anton Vorontsov
2008-06-25 14:32 ` Alan Cox
2008-06-25 15:26 ` Anton Vorontsov
2008-06-25 14:59 ` Anton Vorontsov
2008-06-28 0:54 ` [PATCH v2 -rt] ide: workaround buggy hardware issues with preemptable hardirqs Anton Vorontsov
2008-06-28 1:09 ` Anton Vorontsov
2008-06-28 9:15 ` Alan Cox
2008-06-28 9:14 ` Alan Cox
2008-06-28 10:43 ` Sergei Shtylyov
2008-06-29 12:49 ` Alan Cox
2008-06-29 13:17 ` Sergei Shtylyov
2008-06-29 14:23 ` Anton Vorontsov
2008-06-28 10:30 ` Sergei Shtylyov
2008-06-28 11:31 ` Anton Vorontsov [this message]
2008-06-28 11:52 ` Sergei Shtylyov
2008-06-29 23:26 ` Benjamin Herrenschmidt
2008-06-23 23:52 ` [PATCH -rt] ide: fix interrupts processing issue with preempt-able hardirqs Anton Vorontsov
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=20080628113126.GA438@polina.dev.rtsoft.ru \
--to=avorontsov@ru.mvista.com \
--cc=alan@lxorguk.ukuu.org.uk \
--cc=bzolnier@gmail.com \
--cc=dwalker@mvista.com \
--cc=linux-ide@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=rostedt@goodmis.org \
--cc=sshtylyov@ru.mvista.com \
--cc=tglx@linutronix.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).