[coreboot] v3 CS5536 SMBus bug

[Stefan Reinauer]

Carl-Daniel Hailfinger wrote:
> v3 can't use global variables in stage1 or initram. Same applies to
> static local variables. See the bug below.
>
> Ideas for fixes? The generic variable infrastructure would be one option.
>   

Just call smbus_init() prior to calling smbus_read_byte() the first
time. The variable infrastructure might be a nice idea for some things,
but I think in cases as simple as this, we should not rely on it.

Is there a method to change variables in your "variable infrastructure"
across cpus? If so, it could be useful for semaphores / locking. But I
don't think that's possible since the stuff is in cache, right?
> int smbus_read_byte(u16 device, u8 address)
> {
> 	//BUG here!
> 	static int first_time = 1;
>
> 	if (first_time) {
> 		smbus_init();
> 		first_time = 0;
> 	}
>
> 	return do_smbus_read_byte(SMBUS_IO_BASE, device, address);
> }
>
> Regards,
> Carl-Daniel
>
>   


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