From: Michael Buesch <mb@bu3sch•de>
To: benh@kernel•crashing.org
Cc: linuxppc-dev@ozlabs•org
Subject: Re: Powerbook shuts down hard when hot, patch found
Date: Sun, 30 Sep 2007 12:13:36 +0200 [thread overview]
Message-ID: <200709301213.36821.mb@bu3sch.de> (raw)
In-Reply-To: <1191106145.28637.11.camel@pasglop>
On Sunday 30 September 2007 00:49:05 Benjamin Herrenschmidt wrote:
> Well, it's possible that they have a too weak pull-up resistor on those
> lines, and thus when asserted to 0, a significant current goes through
> causing the whole thing to heat up. That heat added to the residual heat
> of a hot boot becomes then enough to trigger the temperature sensor
> threshold... just one possible explanation.
Possible, yes.
> > That's why I thought about some silicon bug. Why only when it's hot? :)
> >
> > > Also, the other change I made you do turns these into inputs, thus the
> >
> > The _EN bits are already all cleared, as you can see in my printk dump.
> > So clearing them has no effect, of course.
> > So the ports are Inputs as default on boot.
>
> Hrm, that's weird then, because in that case, changing the output bits
> shouldn't have any effect, unless maybe on some chips, the EN bits are
> flipped. I don't have anything specific about the rv350 tho.
>
> Can you print which specific DDC register is doing that (it's called
> twice right ?) and maybe do a patch preventing that write only for one
> of them and let me know if it makes a difference.
Here's the log of a working kernel.
As you can see, I only removed the write for register 0x60 here.
So it only crashes when I clear the bits in this register.
(makes sense, as there's nothing to clear in the other one).
[ 0.453703] PCI: Enabling device 0000:00:10.0 (0006 -> 0007)
[ 0.649319] radeonfb (0000:00:10.0): Invalid ROM signature 303 should be 0xaa55
[ 0.649329] radeonfb: Retrieved PLL infos from Open Firmware
[ 0.649340] radeonfb: Reference=27.00 MHz (RefDiv=12) Memory=203.00 Mhz, System=392.00 MHz
[ 0.649350] radeonfb: PLL min 12000 max 35000
[ 0.650146] DDC REG 0x00000060 IS 0x00000303
[ 0.793754] i2c-adapter i2c-2: unable to read EDID block.
[ 1.013748] i2c-adapter i2c-2: unable to read EDID block.
[ 1.233748] i2c-adapter i2c-2: unable to read EDID block.
[ 1.310002] DDC REG 0x0000006C IS 0x00000000
[ 1.310007] WRITING
[ 1.650506] ieee1394: Host added: ID:BUS[0-00:1023] GUID[001124fffed98036]
[ 1.700986] radeonfb: Monitor 1 type LCD found
[ 1.700995] radeonfb: EDID probed
[ 1.701001] radeonfb: Monitor 2 type no found
[ 1.701015] radeonfb: Using Firmware dividers 0x0002008e from PPLL 0
[ 1.701130] radeonfb: Dynamic Clock Power Management enabled
[ 1.742608] Console: switching to colour frame buffer device 160x53
[ 1.765577] radeonfb: Backlight initialized (radeonbl0)
[ 1.765767] radeonfb (0000:00:10.0): ATI Radeon NP
[ 1.776757] Generic RTC Driver v1.07
[ 1.777085] Macintosh non-volatile memory driver v1.1
[ 1.777429] Linux agpgart interface v0.102
[ 1.777739] agpgart: Detected Apple UniNorth 2 chipset
--
Greetings Michael.
next prev parent reply other threads:[~2007-09-30 10:17 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-09-28 21:32 Powerbook shuts down hard when hot, patch found Michael Buesch
2007-09-28 23:04 ` Benjamin Herrenschmidt
2007-09-29 11:06 ` Michael Buesch
2007-09-29 11:22 ` Michael Buesch
2007-09-29 21:51 ` Benjamin Herrenschmidt
2007-09-29 21:53 ` Michael Buesch
2007-09-29 22:19 ` Benjamin Herrenschmidt
2007-09-29 22:26 ` Michael Buesch
2007-09-29 22:49 ` Benjamin Herrenschmidt
2007-09-30 10:13 ` Michael Buesch [this message]
2007-09-30 10:16 ` Michael Buesch
2007-10-01 8:00 ` Michel Dänzer
2007-10-01 20:58 ` Michael Buesch
2007-10-02 6:43 ` Michel Dänzer
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=200709301213.36821.mb@bu3sch.de \
--to=mb@bu3sch$(echo .)de \
--cc=benh@kernel$(echo .)crashing.org \
--cc=linuxppc-dev@ozlabs$(echo .)org \
/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