Re: Linux-2.6.27-rc5, drm errors in log

Gene Heskett
2008-08-31T10:56:16Z

On Sunday 31 August 2008, Dave Airlie wrote:
>On Sun, Aug 31, 2008 at 12:19 PM, Gene Heskett <gene.heskett@verizon.net> wrote:
>> On Saturday 30 August 2008, Bridgman, John wrote:
>>>))I'm drowning in these errors:
>>>))
>>>))Aug 30 13:21:05 coyote kernel: [14927.850078] [drm] wait for fifo failed
>>> status : 0x80076100 0x00000000
>>>
>>>I'm just going on the code in your email - can't view git until later
>>> today - but in this case it seems like the timeouts were always happening
>>> and now there is code to print an error message.
>>>
>>>IIRC the usual fix is to bump the timeout but (Michael ?) has suggested a
>>> couple of times that the ideal solution would be to change the logic so
>>> that the driver never times out while the chip is making progress (ie
>>> while the number of slots available in the fifo is increasing, even if it
>>> hasn't increased enough yet).
>>
>> FWIW, I added the 3 lines that cause that printout to the 2.6.27-rc4 tree
>> and rebuilt it. There are no more errors being reported now by
>> 2.6.27-rc4, and there were none without those 3 added lines prior to this,
>> so it is rc5 specific.
>
>Hmm I'm just looking at the patches I put in for rc5, and there is no
>functional difference to the
>r200 codepath that I can see from those patches apart from the debug prints.

Update: there were 3 of those in the log after I sent the denial msg.
======
Aug 30 23:48:34 coyote kernel: [ 7242.890000] [drm] wait for fifo failed status : 0x80076100 0x00000000
Aug 30 23:57:51 coyote kernel: [ 7800.370001] [drm] wait for fifo failed status : 0x8003C100 0x00000000
Aug 30 23:57:51 coyote kernel: [ 7800.458000] [drm] wait for fifo failed status : 0x8007C100 0x00000000
======
So this is a real, pre-rc5 problem, but without the reporting that enabled.

>Can you get a clean -rc4 and apply just
> 54f961a628b737f66710eca0b0d95346645dd33e to it.

Yes I can, but how do I get that specific patch? Or is that the git # for the
patch I first applied to -rc2, which added the firmware/radeon stuff? I'm
familiar with patch, but not on a first name basis with git, sorry.

So I'm going to do a bisect, my style. I will rebuild, starting with -rc3,
using only the -rcX patch and the firmware addition patch, which applied to
-rc3 as follows:
now applying [PATCH]radeon_cp-use-request_firmware

patching file drivers/gpu/drm/radeon/radeon_cp.c
patching file drivers/gpu/drm/radeon/radeon_drv.h
patching file drivers/gpu/drm/radeon/radeon_microcode.h
patching file firmware/Makefile
Hunk #1 FAILED at 34.
1 out of 1 hunk FAILED -- saving rejects to file firmware/Makefile.rej
===So I added that into the firmware/Makefile at line 28 by hand===
patching file firmware/WHENCE
Hunk #1 succeeded at 339 (offset -233 lines).
patching file firmware/radeon/R100_cp.bin.ihex
patching file firmware/radeon/R200_cp.bin.ihex
patching file firmware/radeon/R300_cp.bin.ihex
patching file firmware/radeon/R420_cp.bin.ihex
patching file firmware/radeon/R520_cp.bin.ihex
patching file firmware/radeon/RS600_cp.bin.ihex
patching file firmware/radeon/RS690_cp.bin.ihex

patch [PATCH]radeon_cp-use-request_firmware done

=== and I'm watching the build for errors===
It got past the MK_FW for those ok.
However there were 6 section miss-matches reported, and the suggested
addition to .config did not make it any noisier so I'm no smarter.
Now I've added those 3 reporter lines to radeon_cp.c, rebuilt again and
will reboot to -rc3 for effects, reporting after a few hours uptime.

Unless you have a better plan I can learn of course.

>See if you can get that to produce the errors, if it does, apply just
>the drm info chunks, try again, if that works, try adding
>the isync cntl chunk. and re-testing. I can't see how writing isync
>cntl here would affect things though.

>Dave.

--
Cheers, Gene
"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
It is always the best policy to tell the truth, unless, of course,
you are an exceptionally good liar.
-- Jerome K. Jerome
--
Cheers, Gene
"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Equal bytes for women.