[U-Boot] GPIO configuration on 460EX

[U-Boot] GPIO configuration on 460EX

[Felix Radensky]

Hi,

I'm looking at GPIO setup code for Canyonlands, and
it looks like some initializations mentioned in the 460EX
manual are missing. When pin is configured as alternate
input, the corresponding bits in TSRL/H registers should
be set. U-Boot code sets TSRL/H registers only for output
pins.

Am I missing something ?

Thanks a lot.

Felix.

[U-Boot] GPIO configuration on 460EX

[Stefan Roese]

Hi Felix,

On Thursday 16 October 2008, Felix Radensky wrote:
> I'm looking at GPIO setup code for Canyonlands, and
> it looks like some initializations mentioned in the 460EX
> manual are missing. When pin is configured as alternate
> input, the corresponding bits in TSRL/H registers should
> be set. U-Boot code sets TSRL/H registers only for output
> pins.
>
> Am I missing something ?

Looking again at the users manual I can't find that the TSR register should be 
set for input functionality. Take a look at figure 35-1. Here you will see 
that TSR is only involved for output functionality.

I assume that you are asking because of your Linux IRQ problem with the 
external interrupt, correct? I'll take a look at the Linux thread and try to 
give another answer there.

And feel free to test with TSR configured for input as well. If this gets your 
interrupt working then this we need to change this GPIO config code of 
course.

Best regards,
Stefan

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[U-Boot] GPIO configuration on 460EX

[Felix Radensky]

Hi, Stefan

Stefan Roese wrote:
> Hi Felix,
>
> On Thursday 16 October 2008, Felix Radensky wrote:
>   
>> I'm looking at GPIO setup code for Canyonlands, and
>> it looks like some initializations mentioned in the 460EX
>> manual are missing. When pin is configured as alternate
>> input, the corresponding bits in TSRL/H registers should
>> be set. U-Boot code sets TSRL/H registers only for output
>> pins.
>>
>> Am I missing something ?
>>     
>
> Looking again at the users manual I can't find that the TSR register should be 
> set for input functionality. Take a look at figure 35-1. Here you will see 
> that TSR is only involved for output functionality.
>
>   
I was looking at section 35.5.3 and Table 35-9 in user manual (Version 1.14)
TSR is involved in both input and output functionality. This indeed 
contradicts
the description you were referring to. Maybe AMCC guys reading this list can
clarify ?
> I assume that you are asking because of your Linux IRQ problem with the 
> external interrupt, correct? I'll take a look at the Linux thread and try to 
> give another answer there.
>   
Thanks a lot. Your suggestion in this thread indeed helped. I was using
wrong IRQ number in device tree.
> And feel free to test with TSR configured for input as well. If this gets your 
> interrupt working then this we need to change this GPIO config code of 
> course.
>
>   
I've tried that, but it didn't help.

Thanks a lot for you help.

Felix.