connect DFP & CRT monitor to DVI & VGA port of RV370, set video output mode to 1280x1024, VGA port fail to output video in this case. It's because registers FP_HORZ_STRETCH & FP_VERT_STRETCH are not properly initialized in the driver when VGA port is controlled by CRTC1. I suggest initialize these two registers in the function RADEONInitCrtcRegisters and set initial value by RADEONRestoreCrtcRegisters. it's actually how the driver initialize them in master branch.
Created attachment 11129 [details] [review] Set initial value for registers FP_HORZ_STRETCH & FP_VERT_STRETCH
I'll take a look at this tonight. So I assume RMX must always be programmed for crtc1 regardless of whether it's being used or not? Thanks Lisa.
when DFP is connected, BIOS will auto enable RMX stretch for display. however, for RV370, crtc1 is connected to VGA port, enable RMX stretch on this port may cause trouble to CRT monitors. It's better to program FP_HORZ_STRETCH & FP_VERT_STRETCH in driver to ensure both VGA and DFP monitors work properly.
fixed in git: 5b4a04c23e3f1ec2490418b111f417c16463c709 Thanks!
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