Re: kern/51676 (Enhancement - interrupt support for RPI gpio, kevents for gpio.c, PPS driver for gpio, and more)

[Brad Spencer <brad%anduin.eldar.org@localhost>]

thorpej%NetBSD.org@localhost writes:

> Synopsis: Enhancement - interrupt support for RPI gpio, kevents for gpio.c, PPS driver for gpio, and more
>
> Responsible-Changed-From-To: mbalmer->thorpej
> Responsible-Changed-By: thorpej%NetBSD.org@localhost
> Responsible-Changed-When: Mon, 30 Apr 2018 17:20:50 +0000
> Responsible-Changed-Why:
> No action for over 1 year, and I have a need for this, so I'll pick it up.


Hello...

I was the one who put in this PR..  You may want to visit my web site:

http://anduin.eldar.org/stratum-1

and download MUCH improved patches for some of what was in the PR.


I have not had time to update anything to support the FDTization that
occurred with the RPI, so all patches are very much pre-FDT.  Sorry...

I was also mostly unclear if the RPI will support interrupts coming to
more than one CPU core.  Right now, the patches pretty much have CPU0
handle the interrupts.  This won't be a problem for PPS, but may very
well be a problem if there is a high number of interrupts occurring on a
pin, such as what can happen here:

http://anduin.eldar.org/true-rng

for one of the true rng generators I built.



I would love to see GPIO interrupts official for the RPI as well....



-- 
Brad Spencer - brad%anduin.eldar.org@localhost - KC8VKS - http://anduin.eldar.org