Re: [ECOS] interrupt handlers for the ARM SA1110

[Gary Thomas <gthomas@redhat.com>]

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On 18-Jul-2001 Warren Jasper wrote:
> Hi Gary,
> 
>>
>>On 18-Jul-2001 Warren Jasper wrote:
>>> 
>>> This is a directed to Gary Thomas, but any comments are welcome.
>>> 
>>
>>Why me?
> 
> Because your name is on the hal code that I'm interested in :)
> 
> [snip]
> 
>>This would be in hal/arm/sa11x0/travis/current/hal_platform_ints.h
>>(yes, these files are not terribly consistent)  You can add the additional
>>interrupts from the DSP beyond the normal interrupts.  
> 
> OK, let me get this straight.  If I have a file  
> 
> hal/arm/sa11x0/travis/current/include/hal_platform_ints.h
> 
> then that will get included instead of  [in addition to?]
> 
> hal/arm/sa11x0/var/current/include/hal_var_ints.h ???
> 
> I've been grepping around, but I'm not clear on this little bit.
> 

Look in hal/arm/arch/current/include/hal_intr.h  - there is sufficient
mechanism in there to allow a platform to override the variant defaults.

> 
>>As for your cascaded interrupt, all of this support can be handled in
>>your platform code (look at hal/arm/sa11x0/ipaq/current/src/ipaq_misc.c
>>for some examples).  
>>
>>Handling the actual interrupt vectors for your additional sources would
>>involve some changes to the common (/var) code.  This can be added 
>>without too much perturbation, something like this:
>>
>>
>>void hal_interrupt_unmask(int vector)
>>{
>>#ifdef HAL_EXTENDED_INTERRUPT_UNMASK
>>    HAL_EXTENDED_INTERRUPT_UNMASK(vector)
>>#endif
>>    if (vector >= CYGNUM_HAL_INTERRUPT_GPIO11) {
>>        vector = CYGNUM_HAL_INTERRUPT_GPIO;
>>    }
>>    *SA11X0_ICMR |= (1 << vector);
>>}
>>
>>Where (in your platform interrupt file) you'd define 
>>
>>#define HAL_EXTENDED_INTERRUPT_UNMASK
>>    if (vector >= CYGNUM_HAL_INTERRUPT_DSP0) {
>>       // Do whatever is required
>>       return;
>>    }
>>
>>Hopefully you get the picture.  Such additions to the common code would
>>be accepted back into the mainline by us and you'd have the support you
>>need.
> 
> Yes, that is an excellent suggestion.  I need a few days to check out
> my HAL and debug it with the extended exception handler.  Then I'll
> send you my copy of the file:
> 
> hal/arm/sa11x0/var/current/src/sa11x0_misc.c 
> 
> with the hooks for board extended functionality as you suggested.
> 

I'll be glad to look at whatever you come up with.