From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sinan Kaya Subject: Re: [PATCHv2] PCI: QDF2432 32 bit config space accessors Date: Wed, 2 Nov 2016 12:36:16 -0400 Message-ID: <3fd26a0d-a5c2-c385-866e-b957dffb7dda@codeaurora.org> References: <20160921173129.GA20006@localhost> <20160921223805.21652-1-cov@codeaurora.org> <20161031214833.GB14603@bhelgaas-glaptop.roam.corp.google.com> <20161102160820.GA6568@bhelgaas-glaptop.roam.corp.google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20161102160820.GA6568@bhelgaas-glaptop.roam.corp.google.com> Sender: linux-pci-owner@vger.kernel.org To: Bjorn Helgaas , cov@codeaurora.org Cc: Tomasz Nowicki , will.deacon@arm.com, catalin.marinas@arm.com, rafael@kernel.org, Lorenzo.Pieralisi@arm.com, arnd@arndb.de, hanjun.guo@linaro.org, jchandra@broadcom.com, dhdang@apm.com, ard.biesheuvel@linaro.org, robert.richter@caviumnetworks.com, mw@semihalf.com, Liviu.Dudau@arm.com, ddaney@caviumnetworks.com, wangyijing@huawei.com, msalter@redhat.com, linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linaro-acpi@lists.linaro.org, jcm@redhat.com, andrea.gallo@linaro.org, jeremy.linton@arm.com, liudongdong3@huawei.com, gabriele.paoloni@huawei.com, jhugo@codeaurora.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-acpi@vger.kernel.org Hi Bjorn, On 11/2/2016 12:08 PM, Bjorn Helgaas wrote: > On Tue, Nov 01, 2016 at 07:06:31AM -0600, cov@codeaurora.org wrote: >> Hi Bjorn, >> >> On 2016-10-31 15:48, Bjorn Helgaas wrote: >>> On Wed, Sep 21, 2016 at 06:38:05PM -0400, Christopher Covington wrote: >>>> The Qualcomm Technologies QDF2432 SoC does not support accesses >>>> smaller >>>> than 32 bits to the PCI configuration space. Register the appropriate >>>> quirk. >>>> >>>> Signed-off-by: Christopher Covington >>> >>> Hi Christopher, >>> >>> Can you rebase this against v4.9-rc1? It no longer applies to my tree. >> >> I apologize for not being clearer. This patch depends on: >> >> PCI/ACPI: Extend pci_mcfg_lookup() responsibilities >> PCI/ACPI: Check platform-specific ECAM quirks >> >> These patches from Tomasz Nowicki were previously in your pci/ecam-v6 >> branch, but that seems to have come and gone. How would you like to >> proceed? > > Oh yes, that's right, I forgot that connection. I'm afraid I kind of > dropped the ball on that thread, so I went back and read through it > again. > > I *think* the current state is: > > - I'm OK with the first two patches that add the quirk > infrastructure. > > - My issue with the last three patches that add ThunderX quirks is > that there's no generic description of the ECAM address space. > > So if I understand correctly, your Qualcomm patch depends only on the > first two patches. > > Then the question is how the Qualcomm ECAM address space is described. > Your quirk overrides the default pci_generic_ecam_ops with the > &pci_32b_ops, but it doesn't touch the address space part, so I assume > the bus ranges and corresponding address space in your MCFG is > correct. So far, so good. Qualcomm ECAM space includes both the root port and the endpoint address space with a single contiguous 256 MB address space described in MCFG table. There is no need to describe additional resources like PNP0C02. The only thing we missed was 8/16 bits access support on the root port. That's why, we need Cov's patch. > > Is there also an ACPI device that contains that space in _CRS? I > think we concluded that the standard solution is to describe this with > a PNP0C02 device. > > Would you mind opening a bugzilla at bugzilla.kernel.org and attaching > the dmesg log, /proc/iomem, and maybe a DSDT dump? I'd like to have > something to point at to say "if you need an MCFG quirk, you need the > MCFG bit and *also* these other related ACPI device bits, and here's > how it should be done." > > Bjorn > -- Sinan Kaya Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.