From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jon Masters Subject: Re: [PATCH V6 05/13] acpi, pci: Support IO resources when parsing PCI host bridge resources. Date: Wed, 27 Apr 2016 01:36:27 -0400 Message-ID: <57204FDB.6010202@redhat.com> References: <1460740008-19489-1-git-send-email-tn@semihalf.com> <1460740008-19489-6-git-send-email-tn@semihalf.com> <20160427023916.GF6789@localhost> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mx1.redhat.com ([209.132.183.28]:41982 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752541AbcD0Fgh (ORCPT ); Wed, 27 Apr 2016 01:36:37 -0400 In-Reply-To: <20160427023916.GF6789@localhost> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Bjorn Helgaas , Tomasz Nowicki Cc: arnd@arndb.de, will.deacon@arm.com, catalin.marinas@arm.com, rafael@kernel.org, hanjun.guo@linaro.org, Lorenzo.Pieralisi@arm.com, okaya@codeaurora.org, jiang.liu@linux.intel.com, jchandra@broadcom.com, robert.richter@caviumnetworks.com, mw@semihalf.com, Liviu.Dudau@arm.com, ddaney@caviumnetworks.com, wangyijing@huawei.com, Suravee.Suthikulpanit@amd.com, msalter@redhat.com, linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, linaro-acpi@lists.linaro.org On 04/26/2016 10:39 PM, Bjorn Helgaas wrote: > On Fri, Apr 15, 2016 at 07:06:40PM +0200, Tomasz Nowicki wrote: >> Platforms that have memory mapped IO port (such as ARM64) need speci= al >> handling for PCI I/O resources. For host bridge's resource probing c= ase >> these resources need to be fixed up with pci_register_io_range/pci_r= emap_iospace etc. >=20 > ia64 also has memory-mapped I/O port space. The specific references of interest to anyone here are: *). Volume 2, Part 1: Itanium=AE Architecture-based Operating System Interaction Model with IA-32 Applications 2:267 section "10.7 I/O Port Space Model" which describes how they can map 4 "legacy" IO ports on a virtual page when operating in a "sparse" mode. *). Page 378 of the ACPI6.1 specification Table 6-213 I/O Resource Flag (Resource Type =3D 1) Definitions describes how a "sparse" translation = can exist depending upon bit _TRS. This seems to be implemented in Linux using the ACPI_SPARSE_TRANSLATION types. > It would be ideal to find > some way to handle ia64 and ARM64 similarly. At the very least, we > have to make sure that this doesn't break ia64. The ia64 dense/spars= e > I/O spaces complicate things; I don't know if ARM64 has something > similar or not. There's nothing directly similar - it's just regular MMIO. Jon. --=20 Computer Architect | Sent from my Fedora powered laptop -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html