[U-Boot-Users] How to add Timer Interrupt to u-boot?

[U-Boot-Users] How to add Timer Interrupt to u-boot?

[Robert]

Hello all:

    Everybody knows how to add Timer Interrupt to the u-boot?
I wrote a fuction called timer0_isr(), and wanted to add it to Uboot,
but I didn't know what to do,  Does the uboot has a funciton like
function  request_irq() in linux kernel?
    Thanks in advance!

With kind regards,

Robert Xia 

[U-Boot-Users] How to add Timer Interrupt to u-boot?

[Jerry Van Baren]

Robert wrote:
> Hello all:
> 
>     Everybody knows how to add Timer Interrupt to the u-boot?
> I wrote a fuction called timer0_isr(), and wanted to add it to Uboot,
> but I didn't know what to do,  Does the uboot has a funciton like
> function  request_irq() in linux kernel?
>     Thanks in advance!
> 
> With kind regards,
> 
> Robert Xia 

Hi Robert,

Interrupts are not used by u-boot (with some rare exceptions). 
Generally things poll and there is usually some type of counter register 
(processor or board-specific) for measuring elapsed time.

If you really need interrupts, you will probably have to set up the 
vectors, interrupt registers, etc. yourself.

Best regards,
gvb

[U-Boot-Users] How to add Timer Interrupt to u-boot?

[Detlev Zundel]

Hi Robert,

>     Everybody knows how to add Timer Interrupt to the u-boot?
> I wrote a fuction called timer0_isr(), and wanted to add it to Uboot,
> but I didn't know what to do,  Does the uboot has a funciton like
> function  request_irq() in linux kernel?

As Jerry told you, U-Boot generally avoids using interrupts.  

For some architectures however we have code to allow using interrupts,
e.g. from standalone applications.  You can look at
examples/interrupt.c which effectively was written with
cpu/mpc5xxx/interrupts.c in mind.  The latter was of course derived
from the Linux version so it shouldn't be a big problem to do
something similar for other architectures.

Cheers
  Detlev

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