From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: How to "register" a GSI for a non PCI non ISA device Date: Wed, 25 Jan 2012 14:02:14 -0500 Message-ID: <20120125190214.GC18606@phenom.dumpdata.com> References: <20120124184203.1b0878c2@xilun> <4F1F99A5.1000206@kernel.org> <20120125182314.7834c75b@xilun> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from rcsinet15.oracle.com ([148.87.113.117]:63294 "EHLO rcsinet15.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751964Ab2AYTEo (ORCPT ); Wed, 25 Jan 2012 14:04:44 -0500 Content-Disposition: inline In-Reply-To: <20120125182314.7834c75b@xilun> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Guillaume Knispel Cc: Len Brown , linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, Xavier Carcelle , =?iso-8859-1?B?Tm/p?= Rubinstein On Wed, Jan 25, 2012 at 06:23:14PM +0100, Guillaume Knispel wrote: > On Wed, 25 Jan 2012 00:56:53 -0500 > Len Brown wrote: > > > On 01/24/2012 12:42 PM, Guillaume Knispel wrote: > > > > > Hi, > > > > > > I'm building a PC platform with additional non-PCI and non-ISA devices: > > > they are basically simple telecom chipsets connected to an SPI and an > > > old school parallel bus (Intel LEB bus) and GPIO pins that can be used > > > as interrupts through the IO APIC which exposes 40 GSI. From the point > > > of view of the software the SPI, LEB, and GPIO are provided by PCI > > > devices (in reality they are embedded controllers in an Intel SoC > > > 80579). Anyway I'm not sure the additional GSI are described anywhere > > > in whatever black magic ACPI / legacy BIOS table they could be > > > (but I've complete control over the FW, so I can had whatever is > > > needed when I know it). > > > > What is the benefit of implementing ACPI on this custom system? > > For our short term project it seems to be more a necessity than a > benefit. ACPI is supported by the SoC, tables are already largely > provided by Coreboot, the whole x86 ecosystem including Linux is more > or less based around ACPI, and my whole interrogation comes from the > fact that *acpi*_register_gsi() seems to be necessary to configure a > GSI in the APIC but is not exported anymore, so my guess is that if I Hm, isn't it __acpi_register_gsi? > can't call it explicitly from my LKM, there should better be a way to > make it be called when an ACPI thing is done, or maybe a legacy table > parsed. Can you do it the way xen does? Look in arch/x86/xen/pci.c > > As we first target an unmodified (if possible) 2.6.32 kernel from > Debian Squeeze, I can't just re-export acpi_register_gsi() and call it > a day. (If I've no other choice I'll obviously do it, but this would be > quite bad for future maintenance). Oh wow. That is ancient. 3.2?