On Wed, 21 Sep 2016, Ilia Mirkin wrote:
I think you want the reduced blanking modeline:
$ cvt -r 2560 1440
# 2560x1440 59.95 Hz (CVT 3.69M9-R) hsync: 88.79 kHz; pclk: 241.50 MHz
Modeline "2560x1440R" 241.50 2560 2608 2640 2720 1440 1443 1448
1481 +hsync -vsync
This matches your monitor's detailed timings:
[ 55.220] (II) NOUVEAU(0): Supported detailed timing:
[ 55.220] (II) NOUVEAU(0): clock: 241.5 MHz Image Size: 597 x 336 mm
[ 55.220] (II) NOUVEAU(0): h_active: 2560 h_sync: 2608 h_sync_end
2640 h_blank_end 2720 h_border: 0
[ 55.220] (II) NOUVEAU(0): v_active: 1440 v_sync: 1443 v_sync_end
1448 v_blanking: 1481 v_border: 0
Not sure why a 2560x1440 modeline isn't being advertised in EDID -
perhaps the monitor is in some "safe" setting where that's not
reported? Might have to flip it into DP 1.2 mode or something.
I tried the reduced blanking modeline, but the 1920x1080 format persisted.
So I then replaced the display port cables with the cables labelled "DP
V1.2" supplied by iiyama with the monitors. This fixed the problem. I now
have 2560x1440R on two iiyama monitors. I was most agreably surprized
that the nouveau driver automatically placed DP-2 to the right of DP-1 to
form a 5120x1440 surface. Very polished execution by nouveau!
Thanks for your help, Roger
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