Re: Clockport devices configuration layer [was: Re: USB stack vs bus_dma_tag_t]

[Frank Wille <frank%phoenix.owl.de@localhost>]

Radek Kujawa wrote:

>>> clockport0 at mainbus addr 0xd80000 # A1200 mainboard clockport
>>> clockport* at zbus? # various Zorro clockports
>>> tduhc0 at clockport? # E3B SUBWAY USB Controller
>>
>> [...]
>> But what is a Zorro clockport? Does it really exist? Do you have  
>> examples?
>
> It is simply a clockport located on a Zorro card. Best known Zorro  
> cards with clockports include Individual Computers Buddha and X-Surf.  

Ok, but then the clockport should attach to that specific Zorro card and not
to the zbus directly. For example:

ne* at zbus0
clockport* at ne?        # X-surf clockport


> Match code for clockport at zbus should contain list of vendors and  
> device IDs of cards carrying clockport, along with their default base  
> adresses.

When you do it like above the X-surf would know the address of its
clockport.


> In some cases base address of such clockport is static, always the  
> same, and in some cases it is configured dynamically. I think most  
> clockports on Zorro cards are static, but I know at least one that is  
> configurable - clockport on a Deneb USB controller. It is probably  
> possible to change its base address via software.

But the Deneb driver (when it ever exists) would probably know a way to
determine this address, so there is no problem.


-- 
Frank Wille