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Subject: Re: hoo boy, interrupt Handling on BGQ
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Jimi Xenidis <jimix@pobox.com>
Date: Tue, 13 Nov 2012 09:19:27 +1100
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On Mon, 2012-11-12 at 15:33 -0600, Jimi Xenidis wrote:
> So interrupts need to go to FW before Linux, please let not talk about how silly that is.
> Lets talk about something far more silly...
> In order to get to the Linux exception handlers, we have to tell FW where the interrupt page is, and then it _copies_ it.
> 
> IFAICT, this means that each vectors on the "copied" page must:
> 1) construct an 64-bit absolute address to a per vector stub
> 2) leap at the (with bctr or blr)
> 3) restore CTR or LR and anything else that (1) messed up
> 4) normal branch to the actual vector
> 
> This is what I'll be working on, but I'd love to hear any other ideas.

Replace the firmware with something sane ?

Cheers,
Ben.