[Intel-gfx] 945GSE - Component Video Bug

[Mathew McKernan]

Hi all,

I think I have stumbled across a bug with the Intel i915 DRM Module.

I am running the 2.6.37.5 kernel with the intel module for xorg on 2.14.0.

The unit is a single board computer that is connected to a TV via the Component Video Output, this board has a combination Component Video/Composite output.

The issues I am seeing:
- The SBC boots with Component enabled at 480i.
- The kernel starts as normal, but when udev loads the i915 module the kernel drops the output back to NTSC 480i. This disables component and then outputs composite video on the relevant connector.
- I am unable to change the mode using the command below to 576p, 480i etc. There appears to be no kernel dmesg output when I make any adjustments.
	- xrandr changes make no difference when running:
	- xrandr --output TV1 --set mode 576p


Here are some log lines whereby the issue occurs:
[    7.886917] [drm:drm_crtc_helper_set_mode], [CRTC:3]
[    7.886924] [drm:intel_panel_set_backlight], set backlight PWM = 0
[    7.887535] [drm:intel_crtc_mode_set], Mode for pipe A:
[    7.887542] [drm:drm_mode_debug_printmodeline], Modeline 0:"NTSC 480i" 0 107520 1280 1368 1496 1712 1024 1027 1034 1104 0x40 0x0
[    7.890033] [drm:intel_pipe_set_base], No FB bound
[    7.890045] [drm:drm_crtc_helper_set_mode], [ENCODER:12:TV-12] set [MODE:0:NTSC 480i]
[    7.910092] [drm:intel_update_watermarks], plane B (pipe 0) clock: 107520
[    7.910100] [drm:i9xx_get_fifo_size], FIFO size - (0x00001d9c) A: 28
[    7.910108] [drm:i9xx_get_fifo_size], FIFO size - (0x00001d9c) B: 31
[    7.910115] [drm:intel_calculate_wm], FIFO entries required for mode: 0
[    7.910121] [drm:intel_calculate_wm], FIFO watermark level: 26
[    7.910127] [drm:intel_calculate_wm], FIFO entries required for mode: 34
[    7.910133] [drm:intel_calculate_wm], FIFO watermark level: -5
[    7.910139] [drm:i9xx_update_wm], FIFO watermarks - A: 26, B: 1
[    7.910145] [drm:i9xx_update_wm], self-refresh entries: 80
[    7.910151] [drm:i9xx_update_wm], Setting FIFO watermarks - A: 26, B: 1, C: 2, SR 47
[    7.910195] [drm:intel_update_fbc],
[    7.948039] [drm:intel_tv_detect_type], TV detected: 260017, 8f0000aa
[    7.948048] [drm:intel_tv_detect_type], Detected Component TV connection
[    7.948057] [drm:intel_panel_set_backlight], set backlight PWM = 0

I am at a loss as to the cause. I am happy to write a patch or do as much troubleshooting as required but need some direction on where to start.

If it helps, I have a unit running Windows that I can grab information from as the 1080i output is working fine on that and not falling back to NTSC on start.

Thanks!

Matty McKernan
matmckernan at rauland.com.au
North Melbourne Australia