public inbox for linuxppc-dev@ozlabs.org 
 help / color / mirror / Atom feed
From: Eugene Surovegin <ebs@ebshome•net>
To: Rupesh S <rupesh.sugathan@gmail•com>
Cc: linuxppc-embedded@ozlabs•org
Subject: Re: PPC kernel hangs
Date: Tue, 12 Oct 2004 14:36:34 -0700	[thread overview]
Message-ID: <20041012213634.GA4936@gate.ebshome.net> (raw)
In-Reply-To: <1e44ebcf04101214247d3072b6@mail.gmail.com>

On Tue, Oct 12, 2004 at 02:24:50PM -0700, Rupesh S wrote:
> Hi,
> 
> To perform a Memory Mapped access of a device, I setup the OR and BR
> registers in the bootloader (u-boot). I am able to read and write to
> the device being in the u-boot prompt. However, when I try to access
> the device after the Linux kernel boots up (say, in a driver), it
> gives me a exception message as follows.
> #################################################################
> enabl0004, DSISR: 00000063
> TASK = c3ef4000[18] 'insmod' Last syscall: 128
> last math 00000000 last altivec 00000000
> GPR00: C60B0338 C3EF5E50 C3EF4000 60000004 00001032 00000001 C018009E C60B0000
> GPR08: C60B0BB8 C60B085C C60B0BBC C60B0000 C0180000 10056374 00000000 00000000
> 3
> TASK = c3ef4000[18] 'insmod' Last syscall: 128
> last math 00000000 last altivec 00000000
> GPR00: C60B0338 C3EF5E50 C3EF4000 60000004 00001032 00000001 C018009E C60B0000
> GPR08: C60B0BB8 C60B085C C60B0BBC C60B0000 C0180000 10056374 00000000 00000000
> GPR16: 00000000 00000000 00000000 00000000 00009032 C3EF5E98 10064EBC C3E2C000
> GPR24: C02EEA80 00000008 C60B2000 00000060 FFFFFFEA 00000000 C60B0000 C60B0000
> Call backtrace:
> 00000000 C60B0338 C0014DE4 C000447C 10050000 1000B27C 1000C344
> 10003CBC 100038C8 0FE70E88 00000000
> #################################################################
> 
> My platform is MPC880 Processor.
> 
> Do I need to setup something more in the kernel?

Did you use ioremap to get valid kernel virtual address for your 
device registers? You generally cannot just use physical address to 
access device from the device driver.

--
Eugene

  reply	other threads:[~2004-10-12 21:43 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-10-12 21:24 PPC kernel hangs Rupesh S
2004-10-12 21:36 ` Eugene Surovegin [this message]
2004-10-12 23:03   ` Jon Masters
2004-10-12 23:05     ` Jon Masters
2004-10-12 23:34     ` Eugene Surovegin
2004-10-13 18:00       ` Jon Masters
2004-10-14 16:44     ` Rupesh S
2004-10-14 21:23       ` Jon Masters

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=20041012213634.GA4936@gate.ebshome.net \
    --to=ebs@ebshome$(echo .)net \
    --cc=linuxppc-embedded@ozlabs$(echo .)org \
    --cc=rupesh.sugathan@gmail$(echo .)com \
    /path/to/YOUR_REPLY

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