Hi, On Wed, 2009-10-21 at 14:42 +0200, ext Gary Thomas wrote: > I'm using DSS2, currently just with a frame buffer to a > [VGA/RGB] monitor. > > I'm trying to understand how to set the timing parameters > for my device. The simple 'omapfb.mode=1024x768-24@75' > doesn't quite cut it for some of the devices I need to > use. > > Questions: > * How can I get different pixel clocks? I seem to always > end up with 61714285: The pixel clock is calculated based on the given resolution and refresh rate. You can adjust it via sysfs. But you don't have very fine graded control when using the normal pixel clock source. When using DSI PLL to generate the DISPC functional clock, you can get much more exact pixel clock. But DSI PLL support is quite experimental. > # cat /tmp/dbg/omapdss/clk > - dss - > internal clk count 2 > dss_ick 83000000 1 > dss1_alwon_fck 123428570 1 > dss2_alwon_fck 13000000 0 > dss_tv_fck 54000000 0 > dss_96m_fck 96000000 0 > - dispc - > dispc fclk source = dss1_alwon_fclk > pixel clk = 123428570 / 1 / 2 = 61714285 > * How can I control the waveform? In particular, the > size and shape of the "porches"? My display seems to > need these settings: > 61714,1024/26/162/136,768/3/29/6 > I'd like to get this behaviour, either from the boot line > or ideally by default. Currently you cannot set these via kernel arguments, only via sysfs or in the panel driver. > * The display also seems to want the sync pulses to be > asserted low (inverted?). Currently, I have this "hard-wired" > into my display device, but I'd also like this to be adjustable. These cannot currently be changed at all, they can only be defined in the panel driver. Tomi -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
