From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from foss.arm.com ([217.140.101.70]:40180 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750807AbbJPIs0 (ORCPT ); Fri, 16 Oct 2015 04:48:26 -0400 Message-ID: <5620B9D6.1010708@arm.com> Date: Fri, 16 Oct 2015 09:48:22 +0100 From: Marc Zyngier MIME-Version: 1.0 To: Jiang Liu , Thomas Gleixner , Jason Cooper CC: Ma Jun , linux-arm-kernel@lists.infradead.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH RFC 0/7] Adding core support for wire-MSI bridges References: <1444923568-17413-1-git-send-email-marc.zyngier@arm.com> <56205917.7090001@linux.intel.com> In-Reply-To: <56205917.7090001@linux.intel.com> Content-Type: text/plain; charset=windows-1252 Sender: linux-pci-owner@vger.kernel.org List-ID: Hi Gerry, On 16/10/15 02:55, Jiang Liu wrote: > On 2015/10/15 23:39, Marc Zyngier wrote: >> There seems to be a new class of interrupt controller out there whose >> sole purpose (apart from making everybody's life a nightmare) is to >> turn wired interrupts into MSIs. >> >> Instead of considering that the MSIs allocated to a device are for the >> direct use of that device, we can turn this set of MSIs into a irq >> domain, and use that domain to build a standard irqchip on top of >> that. > Hi Marc, > There's a working to enable Intel VMD storage device, which > has the similar requirement. Basically a PCIe hierarchy is hidden > behind a parent PCIe device, so we need to use the PCIe irqs on parent > to de-multiple PCIe IRQs from hidden PCIe devices. Seems a chance for > consolidation here. Do you know if there is a 1-1 mapping between the interrupts seen by the parent device and those seen by the hidden devices? Or is it a case of having to demultiplex the MSIs? Looks like the former, but I'd like to be sure. I just had a quick look at the code there: https://lkml.org/lkml/2015/8/27/674 Is there anything more recent? > cc Keith Busch who is the author of > VMD device driver. Sure, will do when I repost this (probably in a few weeks), and assuming this fits the bill for Thomas and the MBIGEN folks. Thanks, M. -- Jazz is not dead. It just smells funny...