10.0-stable PowerMac G4 boot SSD has X11/xfce4 failing but they work when that SSD boots a PowerMac G5

[Mark Millard]

The following eventually reports that moving a PowerMac G4 FreeBSD boot SSD to a PowerMac G5 and booting from it makes X11 with xfce4 go from not working to working. (No other changes are involved.)


Earlier when trying the "/dev/mem instead of /dev/console for memory-mapping frame buffers in X11 on PowerPC" testing I had reported that I was unable to get to the point of a reasonable test on PowerMac G4's, including for NVIDIA. (http://lists.freebsd.org/pipermail/freebsd-ppc/2014-July/007124.html)

> PowerMac G4 (3,6), GeForce4 Ti 4600: UI hangs during the initial xfce4 "welcome" screen update, frequently without the background being finished. What is displayed seems fine as far as it got. Can still Option-Fn just fine to get back to VTn and use it.

The "PowerMac G4 (3,6), ATI Radeon 9000/PRO If (AGP/PCI)" was far worse off for as much as I tested back then: random varying garbage displayed and it ignored my input after attempting to switch back to to a VTn. Forced power switch based shutdown.

Now that I've access to the Power Mac's again I experimented more with "PowerMac G4 (3,6), ATI Radeon 9000/PRO If (AGP/PCI)" and I managed to make it work better then what I reported before. Avoiding DRI (use NoAccel or use "False" for DRI) makes the Radeon behave the similar to the NVIDIA GeForce4 Ti 4600 as indicated above. The difference is that the VTn stays black when I switch to it. But it does take what I type and executes the commands, such as reboot. (Yep: still syscons.)

In both G4 contexts the Xorg.0.log that results appears to have no information indicating any failure. Of course in each case /etc/X11/xorg.conf was generated (-configure) for the card in use, but with NoAccel in use.

The SSD has:

FreeBSD FBSDG4S0 10.0-STABLE FreeBSD 10.0-STABLE #0 r268571: Sun Jul 13 05:15:31 UTC 2014     root at grind.freebsd.org:/usr/obj/powerpc.powerpc/usr/src/sys/GENERIC  powerpc



BUT...

Now switching that SSD to a G5 PowerMac and booting from it: PowerMac G5 (7,2), Radeon 9800PRO NH (AGP)

Using the same Radeon /etc/X11/xorg.conf (with NoAccel enabled or with "False" for DRI in each context): X11 with xfce4 works fine! 

Even switching to a VTn works fine on the G5 PowerMac: it is displays correctly instead of ending up with a black screen.



The generated -configure xorg.conf.new is the same for the two Radeon contexts. But in each case I need to pick an option that disables DRI use in order to get reasonable behavior.

Without NoAccel/"False"-for-DRI for the G5: text does not display correctly and if composite is enabled with shadows then the shadowing is messed up. Bit/Byte order/alignment issues when accelerated?

The Radeon 9000 with DRI enabled gets a Xorg.0.log report that r200_dri.so is not found and the Radeon 9800 with DRI enabled gets a report that r300_dri.so is not found. (As is probably expected in each case.) So the behaviors are examples of the error handling for "not found".



Mac OS X 10.4 works fine in all the PowerMacs involved: no evidence of problems.


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Mark Millard
markmi at dsl-only.net