Re: use interrupt without clearing ?

On Mon, Oct 12, 2015 at 5:53 AM, Michael Ellerman [off-list ref] wrote:

On Sun, 2015-10-11 at 15:13 +0300, Ran Shalit wrote:

quoted

Hello,

Is it possible to register an interrupt (in linux), without using the
automatic clear of interrupt.
I need this just for testing.

Hi Ran,

You need to give us much more info than that before anyone will be able to
answer your question. Linux runs on lots of different powerpc machines, so
without knowing what hardware you're talking about it's impossible to
answer.

cheers

Hi,

The interrupt for external IRQ.
It is configured in device tree as following:


intc4@0{
compatible = "intc4";
 #address-cells = <1>;
 #size-cells = <0>;
 reg = <0 0x1000>;
 interrupts = <20 0x8> ;
 interrupt-parent = <&ipic>;
};

It works OK (with normal clearing of interrupt), but we need to
implement a testing requirement as following (startup BIT  testing):

1. an interrupt is given - and not being cleared automatically
2. need to validate that there is a pending interrupt
3. and then we can clear the interrupt and restore the mechnism to its
normal usage (automatic cleari of interrupt)

Regards,
Ran