On Feb 20, 2006, at 3:18 PM, Jason Thorpe wrote:

>
> On Feb 20, 2006, at 3:10 PM, Peter Seebach wrote:
>
>> Well, the alternative proposed appears to be to essentially  
>> completely
>> duplicate the entire i2c bus architecture in a given platform's  
>> machdep.c,
>> giving us two copies of all of that code, and leaving it subject  
>> to bit rot
>> and divergence.
>
> No, that's not the alternative.  If you need to use I2C early, then  
> bootstrap the I2C back-end driver early and use it (the I2C exec  
> code can handle this -- Wasabi has/had at least one platform that  
> uses I2C early in this way, although that code is not available in  
> the public tree, unfortunately).

Here's a hint:

1- Modify the chip-specific i2c back-end to return an i2c_tag_t  
suitable for use in early bootstrap.

2- In machdep code, get the bootstrap i2c tag and use it to call  
seeprom_bootstrap_read() to get the data you want.

3- In device_register(), use device properties to associate the data  
read out of the SEEPROM with the appropriate emac instance.

-- thorpej