README.multihead revision 1.1.1.2
1 1.1 mrg WARNING: 2 1.1 mrg On exit XFree86 restores the old mode but it 3 1.1 mrg does not disable the secondary card. As a result 4 1.1 mrg the second card (which has some randonm CRTC timing) 5 1.1 mrg may produce synch pulses which are wrong for your 6 1.1 mrg monitor. 7 1.1 mrg 8 1.1 mrg If your monitor does not tolerate bad timing I would 9 1.1 mrg recommend that you don't try Multi-head yet, or at 10 1.1 mrg least, turn it off *before* leaving X. 11 1.1 mrg 12 1.1 mrg 13 1.1 mrg 3.9Nl notice: There is a problem with releasing 14 1.1 mrg of LBX colormap privates which may cause a seg. 15 1.1 mrg fault when the server exits. I got a patch from 16 1.1 mrg Mark Vojkovich which fixes it. 17 1.1 mrg 18 1.1 mrg If you have a CL-GD5480 or CL-GD5446 ver. B you 19 1.1 mrg should be able to try Multi-Head with that 20 1.1 mrg card as a secondary. The primary card should not 21 1.1 mrg have any special feature. Some MainBoards may 22 1.1 mrg not do it right too. I tried it with a 5465 (AGP) 23 1.1 mrg as a primary and 5446B (PCI) secondary on an 24 1.1 mrg ABIT LX6 upgraded to the latest bios. 25 1.1 mrg 26 1.1 mrg Version A of the 5446 cannot be pure MMIO (The driver 27 1.1 mrg requires that it is the primary display adapter). 28 1.1 mrg You can distinguish between the rel A and rel B by 29 1.1 mrg running "scanpci -v". Version 1 does not report a 30 1.1 mrg valid BASE1 address. 31 1.1 mrg 32 1.1 mrg The bios upgrade lets me chose if the primary 33 1.1 mrg display adapter is on PCI on AGP (I chose 34 1.1 mrg the AGP card as primary). Warning - this setup 35 1.1 mrg will *NOT* work with XFree86 3.3.2. 36 1.1 mrg 37 1.1 mrg The only problem that I found so far is with 38 1.1 mrg memory configuration initialization. My bios 39 1.1 mrg does not initialize the secondary display adapter. 40 1.1.1.2 mrg This results in a corrupted display. 41 1.1 mrg 42 1.1 mrg Here are the options: 43 1.1 mrg 1. warm booting from Windows 98 may work. I have 44 1.1 mrg not tried that. 45 1.1 mrg 46 1.1 mrg 2. Take out the other card and leave the 5446 47 1.1 mrg (or 5480) as the primary card. Start the server 48 1.1 mrg and watch it's output. Look for lines like: 49 1.1 mrg (--) CIRRUS(0): Memory Config reg 1 is 0x1B 50 1.1 mrg (--) CIRRUS(0): Memory Config reg 2 is 0x21 51 1.1 mrg Remember these values. Now edit XF86Config 52 1.1 mrg and add to the proper device section the lines: 53 1.1 mrg Option "MemCFG1" "0x1B" 54 1.1 mrg Option "MemCFG2" "0x21" 55 1.1 mrg These values are the contents of registers SR0F 56 1.1 mrg and SR17. (notice: the 5480 driver does not use 57 1.1 mrg and will not print MemCFG2). 58 1.1 mrg 59 1.1 mrg Now you can reinstall the other card (which 60 1.1 mrg must me set as the the primary display adaptor). 61 1.1 mrg 62 1.1 mrg A note about configuring multi-head: 63 1.1 mrg There should be a separate section for each 64 1.1 mrg adapter (device), Monitor and Screen. A "ServerLayout" 65 1.1 mrg section is optional (and recommended). To make it 66 1.1 mrg easier for XFree86 to relate device sections to 67 1.1 mrg actual cards, use a BusId line in each device 68 1.1 mrg section. XFree86 3.9N works properly if the config 69 1.1 mrg file is for Multi-head but it finds only one 70 1.1 mrg display adapter. 71
Indexes created Tue Oct 27 00:25:24 UTC 2026