From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ig0-f176.google.com ([209.85.213.176]:36433 "EHLO mail-ig0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932082AbbIXAeS (ORCPT ); Wed, 23 Sep 2015 20:34:18 -0400 Message-ID: <56034505.1080301@gmail.com> Date: Wed, 23 Sep 2015 17:34:13 -0700 From: David Daney MIME-Version: 1.0 To: "Sean O. Stalley" CC: bhelgaas@google.com, yinghai@kernel.org, rajatxjain@gmail.com, mst@redhat.com, zajec5@gmail.com, gong.chen@linux.intel.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-api@vger.kernel.org Subject: Re: [PATCH v2 0/2] PCI: Add support for PCI Enhanced Allocation "BARs" References: <1443047264-4003-1-git-send-email-sean.stalley@intel.com> In-Reply-To: <1443047264-4003-1-git-send-email-sean.stalley@intel.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-pci-owner@vger.kernel.org List-ID: Hi Sean, Thanks for doing this, I think we will use it for Cavium ThunderX. A couple of questions... On 09/23/2015 03:27 PM, Sean O. Stalley wrote: > PCI Enhanced Allocation is a new method of allocating MMIO & IO > resources for PCI devices & bridges. It can be used instead > of the traditional PCI method of using BARs. > > EA entries are hardware-initialized to a fixed address. > Unlike BARs, regions described by EA are cannot be moved. > Because of this, only devices which are permanently connected to > the PCI bus can use EA. A removable PCI card must not use EA. > > This patchset adds support for using EA entries instead of BARs > on Root Complex Integrated Endpoints. > > The Enhanced Allocation ECN is publicly available here: > https://www.pcisig.com/specifications/conventional/ECN_Enhanced_Allocation_23_Oct_2014_Final.pdf > > > Changes from V1: > - Use generic PCI resource claim functions (instead of EA-specific functions) > - Only add support for RCiEPs (instead of all devices). Why not all devices? The spec. allows for EA on devices behind bridges. > - Removed some debugging messages leftover from early testing. > > > Sean O. Stalley (2): > PCI: Add Enhanced Allocation register entries > PCI: Add support for Enhanced Allocation devices > > drivers/pci/pci.c | 174 ++++++++++++++++++++++++++++++++++++++++++ > drivers/pci/pci.h | 1 + > drivers/pci/probe.c | 3 + > include/uapi/linux/pci_regs.h | 40 +++++++++- > 4 files changed, 217 insertions(+), 1 deletion(-) >