Bug 15583

Summary: Panel bloom on X startup with iBook and Radeon M7
Product: xorg Reporter: Dan Williams <dcbw>
Component: Driver/RadeonAssignee: xf86-video-ati maintainers <xorg-driver-ati>
Status: RESOLVED INVALID QA Contact: Xorg Project Team <xorg-team>
Severity: normal    
Priority: medium CC: airlied
Version: unspecified   
Hardware: Other   
OS: All   
Whiteboard:
i915 platform: i915 features:
Attachments:
Description Flags
Xorg log with prints of LVDS and PIXCLK reads & writes none

Description Dan Williams 2008-04-18 08:07:20 UTC 
Created attachment 16017 [details]
Xorg log with prints of LVDS and PIXCLK reads & writes

PowerMac4,3

White iBook G3 800MHz 32MB VRAM with Radeon Mobility 7500.

Xorg logs which print out LVDS and PIXCLK info here:

http://bigw.org/~dan/x-debug.log

I've narrowed down the issue to legacy_output.c, RADEONEnableDisplay(), around line 865 where it does:

862                     tmp |= RADEON_LVDS_DISPLAY_DIS;
863                     tmp &= ~(RADEON_LVDS_ON | RADEON_LVDS_BLON | RADEON_LVDS_EN);
864     ErrorF("%s (#%d): WRITE 0x%lX -> RADEON_LVDS_GEN_CNTL\n", __func__, __LINE__, tmp);
865                     OUTREG(RADEON_LVDS_GEN_CNTL, tmp);

the problem write is 0x52622 -> LVDS_GEN_CNTRL.  At this point the panel bloom starts.  Switching VTs after X has started also corrupts the font (looks like every other vertical pixel column is not displayed or something), not sure if that's related at all.
Comment 1 Dan Williams 2008-04-18 08:18:28 UTC 
Actual backtrace at this point is:

(gdb) bt
#0  RADEONEnableDisplay (output=<value optimized out>, bEnable=<value optimized out>) at /usr/include/xorg/compiler.h:1232
#1  0x0e82da38 in radeon_dpms (output=<value optimized out>, mode=3) at radeon_output.c:433
#2  0x0e82a074 in RADEONBlank (pScrn=<value optimized out>) at radeon_crtc.c:703
#3  0x0e812350 in RADEONScreenInit (scrnIndex=0, pScreen=0x102677b0, argc=<value optimized out>, argv=<value optimized out>) at radeon_driver.c:3067
#4  0x10021990 in AddScreen ()
#5  0x1006593c in InitOutput ()
#6  0x10022178 in main ()
(gdb) 

where the line in RADEONEnableDisplay() that is causing the issue is the line #865 as described in my previous comment.
Comment 2 Dan Williams 2010-07-20 09:04:45 UTC 
Closing as I don't have the hardware anymore and even if I did nobody really makes up-to-date PPC distros either.

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