From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S970232AbdDTN0G (ORCPT ); Thu, 20 Apr 2017 09:26:06 -0400 Received: from mail.kernel.org ([198.145.29.136]:52444 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S970195AbdDTNZ7 (ORCPT ); Thu, 20 Apr 2017 09:25:59 -0400 Date: Thu, 20 Apr 2017 08:25:54 -0500 From: Bjorn Helgaas To: Lorenzo Pieralisi Cc: linux-pci@vger.kernel.org, Wenrui Li , Gabriele Paoloni , Catalin Marinas , Shawn Lin , Will Deacon , Michal Simek , Thierry Reding , Tanmay Inamdar , Zhou Wang , Jonathan Corbet , Pratyush Anand , Russell King , Bharat Kumar Gogada , Murali Karicheri , Benjamin Herrenschmidt , Arnd Bergmann , Jon Mason , Ray Jui , John Garry , Joao Pinto , Bjorn Helgaas , Mingkai Hu , linux-arm-kernel@lists.infradead.org, Thomas Petazzoni , Jingoo Han , linux-kernel@vger.kernel.org, Stanimir Varbanov , Minghuan Lian , "Luis R . Rodriguez" , Roy Zang Subject: Re: [PATCH v4 00/21] PCI: fix config space memory mappings Message-ID: <20170420132554.GA8377@bhelgaas-glaptop.roam.corp.google.com> References: <20170419164913.19674-1-lorenzo.pieralisi@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170419164913.19674-1-lorenzo.pieralisi@arm.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 19, 2017 at 05:48:49PM +0100, Lorenzo Pieralisi wrote: > This patch series[1] is a v4 of a previous version: Applied to pci/ioremap for v4.12, thanks, Lorenzo! > v3 -> v4: > - Reverted back to pci_remap_cfgspace() interface for lack of > consensus on ioremap_nopost() semantics > - Dropped pci_remap_iospace() rework (owing to lack of adequate > pgprot_* attribute description across arches) > - Updated pci_remap_cfgspace() comments > > v3: http://lists.infradead.org/pipermail/linux-arm-kernel/2017-April/500838.html > > v2 -> v3: > - Created a default ioremap_nopost() implementation in a separate > asm-generic header and patched all arches to make use of it > - Removed PCI drivers patches from the series to simplify the > review, they will be posted separately once the ioremap_nopost() > interface is settled > - Fixed devm_ioremap_* BUS offset comments and implemented > nopost interface on top of it > - Added collected tags > > v2: https://lkml.org/lkml/2017/3/27/220 > > v2 -> v3: > - Fixed devm_ioremap_* BUS offset comments and implemented > nopost interface on top of it > - Added collected tags > > v1: https://lkml.org/lkml/2017/2/27/228 > > v1 -> v2: > - Changed pci_remap_cfgspace() to more generic ioremap_nopost() > interface > - Added pgprot_nonposted > - Fixed build errors on arches not relying on asm-generic headers > - Added PCI versatile host controller driver patch > - Added missing config space remapping to hisilicon host controller > > PCI local bus specifications (Rev3.0, 3.2.5 "Transaction Ordering > and Posting") strictly require PCI configuration and I/O Address space > write transactions to be non-posted. > > Current crop of DT/ACPI PCI host controllers drivers relies on > the ioremap interface to map ECAM and ECAM-derivative PCI config > regions and pci_remap_iospace() to create a VMA for mapping > PCI host bridge I/O Address space transactions to CPU virtual address > space. > > On some platforms (ie ARM/ARM64) ioremap fails to comply with the PCI > configuration non-posted write transactions requirement, because it > provides a memory mapping that issues "bufferable" or, in PCI terms > "posted" write transactions. Likewise, the current pci_remap_iospace() > implementation maps the physical address range that the PCI translates > to I/O space cycles to virtual address space through pgprot_device() > attributes that on eg ARM64 provides a memory mapping issuing > posted writes transactions, which is not PCI specifications compliant. > > This patch series[1] addresses both issues in one go: > > - It updates the pci_remap_iospace() function to use a page mapping > that guarantees non-posted write transactions for I/O space addresses > - It adds a kernel API to remap PCI config space resources, so that > architecture can override it with a mapping implementation that > guarantees PCI specifications compliancy wrt non-posted write > configuration transactions > - It updates all PCI host controller implementations (and the generic > ECAM layer) to use the newly introduced mapping interface > > Tested on Juno ECAM based interface (DT/ACPI). > > Non-ECAM PCI host controller drivers patches need checking to make > sure that: > > - I patched the correct resource region mapping for config space > - There are not any other ways to ensure posted-write completion > in the respective pci_ops that make the relevant patch unnecessary > > [1] git://git.kernel.org/pub/scm/linux/kernel/git/lpieralisi/linux.git pci/config-io-mappings-fix-v4 > > Cc: Pratyush Anand > Cc: Arnd Bergmann > Cc: Jonathan Corbet > Cc: Will Deacon > Cc: Jingoo Han > Cc: Bjorn Helgaas > Cc: Mingkai Hu > Cc: Tanmay Inamdar > Cc: Murali Karicheri > Cc: Russell King > Cc: Bharat Kumar Gogada > Cc: Ray Jui > Cc: Wenrui Li > Cc: Shawn Lin > Cc: Minghuan Lian > Cc: Catalin Marinas > Cc: Jon Mason > Cc: Gabriele Paoloni > Cc: Thomas Petazzoni > Cc: Joao Pinto > Cc: Thierry Reding > Cc: Luis R. Rodriguez > Cc: Michal Simek > Cc: Stanimir Varbanov > Cc: Zhou Wang > Cc: Roy Zang > > Lorenzo Pieralisi (21): > PCI: remove __weak tag from pci_remap_iospace() > linux/io.h: add PCI config space remap interface > ARM64: implement pci_remap_cfgspace() interface > ARM: implement pci_remap_cfgspace() interface > lib: fix Devres devm_ioremap_* offset parameter kerneldoc description > PCI: implement Devres interface to map PCI config space > PCI: ECAM: use pci_remap_cfgspace() to map config region > PCI: xilinx: update PCI config space remap function > PCI: xilinx-nwl: update PCI config space remap function > PCI: spear13xx: update PCI config space remap function > PCI: rockchip: update PCI config space remap function > PCI: qcom: update PCI config space remap function > PCI: iproc-platform: update PCI config space remap function > PCI: designware: update PCI config space remap function > PCI: armada8k: update PCI config space remap function > PCI: xgene: update PCI config space remap function > PCI: tegra: update PCI config space remap function > PCI: hisi: update PCI config space remap function > PCI: layerscape: update PCI config space remap function > PCI: keystone-dw: update PCI config space remap function > PCI: versatile: update PCI config space remap function > > Documentation/driver-model/devres.txt | 6 ++- > arch/arm/include/asm/io.h | 10 ++++ > arch/arm/mm/ioremap.c | 7 +++ > arch/arm/mm/nommu.c | 12 +++++ > arch/arm64/include/asm/io.h | 10 ++++ > drivers/pci/dwc/pci-keystone-dw.c | 2 +- > drivers/pci/dwc/pci-layerscape.c | 2 +- > drivers/pci/dwc/pcie-armada8k.c | 2 +- > drivers/pci/dwc/pcie-designware-host.c | 12 +++-- > drivers/pci/dwc/pcie-hisi.c | 7 ++- > drivers/pci/dwc/pcie-qcom.c | 2 +- > drivers/pci/dwc/pcie-spear13xx.c | 2 +- > drivers/pci/ecam.c | 6 ++- > drivers/pci/host/pci-tegra.c | 4 +- > drivers/pci/host/pci-versatile.c | 3 +- > drivers/pci/host/pci-xgene.c | 4 +- > drivers/pci/host/pcie-iproc-platform.c | 3 +- > drivers/pci/host/pcie-rockchip.c | 2 +- > drivers/pci/host/pcie-xilinx-nwl.c | 2 +- > drivers/pci/host/pcie-xilinx.c | 2 +- > drivers/pci/pci.c | 84 +++++++++++++++++++++++++++++++++- > include/linux/io.h | 19 ++++++++ > include/linux/pci.h | 5 ++ > lib/devres.c | 6 +-- > 24 files changed, 183 insertions(+), 31 deletions(-) > > -- > 2.10.0 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel