Re: [PATCH] fb/intelfb: Do not depend on EMBEDDED

From: Krzysztof Halasa
Date: Wed Dec 16 2009 - 18:20:01 EST


Dave Airlie <airlied@xxxxxxxx> writes:

> Currently with the command line video=, this isn't optimal but still
> nobody has come up with a way to make fbset useful since it can't deal
> with multiple heads.

Ahh, now I can see it.

> also the old intelfb didn't deal with analog rgb tv at all.

Well... actually, it did: intelfb works very well if a correct mode is
set (a trivial patch adjusting the clock lower limit to 13.5 MHz may be
needed, or one can use the double clock and resolution, or maybe 1:1
pixel aspect ratio etc). It's not about the CH7xxx encoder, the TV is
connected directly to VGA output.

E.g.

# PAL 720x576, 50 Hz, Interlaced (13.5 MHz dotclock)
#
# Horizontal Vertical
# Resolution 720 576
# Scan Frequency 15.625 kHz 50 Hz (I)
# Sync Width 4.296 us 1.280 ms
# Front Porch 1.000 us 0.256 ms
# Back Porch 5.370 us 1.600 ms
# Active Time 53.333 us 36.864 ms
# Blank Time 10.667 us 3.136 ms
# Polarity Negative Negative
#
# H: 720 + 14 + 58 + 72 = 864
# V: 576 + 4 + 20 + 25 = 625

mode "PAL"
# D: 13.5 MHz, H: 15.625 kHz, V: 50 Hz
geometry 720 576 720 576 32
timings 74074 72 14 25 4 58 20
laced true
hsync low
vsync low
endmode

"fbset PAL" is all one needs to use it.

(I know i915 doesn't have interlaced mode support for analog VGA out,
not a problem).
--
Krzysztof Halasa
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