[coreboot] TV-Out Plan - need suggestions

joe at settoplinux.org joe at settoplinux.org
Fri Apr 18 04:44:06 CEST 2008

Starting to work on the TV-Out code for the RCA RM4100, and I need some help. Here is the Logical Plan:

1. Setup a custom vga init (similar to Corey's vga.c for the cn700 northbridge) that will call a i2c (i810_i2c.c which could be used for a bunch of intel nothbridges) driver from coreboot-v2/src/drivers/i2c/ that will setup communications with the Tv encoder via the GPIO (sda, sdl) lines in the nothbridge.
2. Then setup a init (that would program the registers, and fire it up)for the Tv encoder coreboot-v2/src/drivers/tv-out which could also be called from the nothbridge vga.c.

Here is where it gets tricky. I want to make it dynamic in the respect that you could specify from your mainboard directory:
a. TV-out settings (with a header file??) like NTSC, PAl, resolution, macrovision, filters, etc.
a. enable TV encoder usage (if yes setup i2c, otherwise just skip over it)
b. Specify which Tv encoder to use

This would broaden the horizons and allow other boards that have TV-out to use this code also. The only thing I can think to do is setup some global parameters? Suggestions?

Joseph Smith

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