[9fans] questions on sis630 driver...

[paurea@gsyc.escet.urjc.es]

I continue trying to write the sis630 driver and have a lot of questions.
Forgive me if they are really naive, it is the first time I try to write a
driver... I am still fighting with aux/vga.
The questions are on how should I map and use fb memory and mmio.
I have finally understand that the mmio ports and the address of the video
memory are configured using some PCI configuration registers.

I don't have a pnp bios. I don't know what plan9 pnp capabilities are
(haven't found anything by browsing the source). Anyway I have found
that the BAR registers of the card are set to zero. This gets me to my two
questions.

1) Which addresses do I choose for the framebuffer and the mmio registers?.
I have to set the card's register to them... (can I use segattach for that?)

2) After choosing the addresses and setting the card to them, how do I
   access them?. I have been looking to the vgaxio function and
   haven't been able to understand how does it know where the
   registers are mapped...  Do I have to write to the PCI register the
   absolute address and use myself the address minus 0x80000000 for
   the pointers?. How does vgaxio know what the base address is?

TIA
--
                 Saludos, Gorka

"Curiosity sKilled the cat"