Bug 13913

Summary: 2.6.31-rc5 with radeon KMS enabled fails to boot on X1300 Pro
Product: Drivers Reporter: Adam Tkac (vonsch)
Component: Video(DRI - non Intel)Assignee: drivers_video-dri
Status: CLOSED CODE_FIX    
Severity: normal CC: akpm, alexdeucher, rjw
Priority: P1    
Hardware: All   
OS: Linux   
Kernel Version: 2.6.31-rc5 Subsystem:
Regression: Yes Bisected commit-id:
Bug Depends on:    
Bug Blocks: 13615    

Description Adam Tkac 2009-08-04 16:55:15 UTC 
2.6.31-rc5 fails to boot on the video card specified below (lspci output):

01:00.0 VGA compatible controller: ATI Technologies Inc RV516 [Radeon X1300/X1550 Series]
01:00.1 Display controller: ATI Technologies Inc RV516 [Radeon X1300 Pro] (Secondary)

When machine is booting screen gets blank when normally "kernel output letters become smaller" - I think it is time when radeonfb code gets executed.

I bisected revisions between 2.6.31-rc4 (fine) and 2.6.31-rc5 (bad) and the first bad revision is:

commit 7a50f01a4ab89d5c05eb2cf62e206ac0bfc61d2c
Author: Dave Airlie <airlied@redhat.com>
Date:   Tue Jul 21 20:39:30 2009 +1000

    drm/radeon/kms: vram sizing on certain r100 chips needs workaround.

Note that current master (a33a052f19a21d727847391c8c1aff3fb221c472) doesn't work as well.

Feel free to ask me for more details if needed.
Comment 2 Andrew Morton 2009-08-05 23:53:21 UTC 
I marked this as a regression.

Please do test the patch which Alex identifed and let us know?

Thanks.
Comment 3 Alex Deucher 2009-08-05 23:57:25 UTC 
Dave requested that Linus pull that patch as part of his last drm update so I think it may already be in a newer rc.
Comment 5 Adam Tkac 2009-08-06 08:50:32 UTC 
Yes, patch written in comment #1 fixes the problem. Thanks.
Comment 6 Rafael J. Wysocki 2009-08-09 23:02:25 UTC 
Fixed by commit 0924d942256ac470c5f7b4ebaf7fe0415fc6fa59 .