with the help of xvilka, idwer and roysjosh i did my first board enable today. it was a standard awdflash RE job; the disassembly is on xvilka's gobby server, if you are interested.
we have identified two parts. the first is equivalent to the enable_flash_sb400 chipset enable, the second one sets a gpio line of the sb400 to one.
this was confirmed by the sb7xx datasheet (thanks roysjosh for the hint!); see amd document 43009 http://support.amd.com/us/psearch/Pages/psearch.aspx?type=2.2;2.3&produc...
i have attached the patch, which is not for inclusion yet (still untested).
the main reason i am posting now it the question if i should generalize this. i was thinking about something like intel_ich_gpio_set. because the gpio registers of the sb400 and sb7xx are spread out quite randomly we would need a mapping including: - gpio# (can be array index but i would include it for a sanity check) - output enable register address - output enable register bit - output register address - output register bit
since this is the first time we need a board enable for this southbridge family i am wondering if it is worth it at all... but i would work on it if you wish.