From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-11.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 199BAC43464 for ; Mon, 21 Sep 2020 11:26:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D16ED20874 for ; Mon, 21 Sep 2020 11:26:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726743AbgIUL0m (ORCPT ); Mon, 21 Sep 2020 07:26:42 -0400 Received: from lhrrgout.huawei.com ([185.176.76.210]:2900 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726596AbgIUL0l (ORCPT ); Mon, 21 Sep 2020 07:26:41 -0400 Received: from lhreml710-chm.china.huawei.com (unknown [172.18.7.106]) by Forcepoint Email with ESMTP id BED74476BC36C441F46C; Mon, 21 Sep 2020 12:26:39 +0100 (IST) Received: from localhost (10.52.121.13) by lhreml710-chm.china.huawei.com (10.201.108.61) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1913.5; Mon, 21 Sep 2020 12:26:39 +0100 Date: Mon, 21 Sep 2020 12:25:00 +0100 From: Jonathan Cameron To: Sean V Kelley CC: , , , , , , , Subject: Re: [PATCH v5 06/10] PCI/RCEC: Add pcie_link_rcec() to associate RCiEPs Message-ID: <20200921122500.000032ff@Huawei.com> In-Reply-To: <20200918204603.62100-7-sean.v.kelley@intel.com> References: <20200918204603.62100-1-sean.v.kelley@intel.com> <20200918204603.62100-7-sean.v.kelley@intel.com> Organization: Huawei Technologies Research and Development (UK) Ltd. X-Mailer: Claws Mail 3.17.4 (GTK+ 2.24.32; i686-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.52.121.13] X-ClientProxiedBy: lhreml744-chm.china.huawei.com (10.201.108.194) To lhreml710-chm.china.huawei.com (10.201.108.61) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 18 Sep 2020 13:45:59 -0700 Sean V Kelley wrote: > A Root Complex Event Collector provides support for > terminating error and PME messages from associated RCiEPs. > > Make use of the RCEC Endpoint Association Extended Capability > to identify associated RCiEPs. Link the associated RCiEPs as > the RCECs are enumerated. > > Co-developed-by: Qiuxu Zhuo > Signed-off-by: Qiuxu Zhuo > Signed-off-by: Sean V Kelley A couple of minor things inline plus follow through on not special casing the older versions of the capability. Otherwise looks good to me. Reviewed-by: Jonathan Cameron > --- > drivers/pci/pci.h | 2 + > drivers/pci/pcie/portdrv_pci.c | 3 ++ > drivers/pci/pcie/rcec.c | 96 ++++++++++++++++++++++++++++++++++ > include/linux/pci.h | 1 + > 4 files changed, 102 insertions(+) > > diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h > index 7b547fc3679a..ddb5872466fb 100644 > --- a/drivers/pci/pci.h > +++ b/drivers/pci/pci.h > @@ -474,9 +474,11 @@ static inline void pci_dpc_init(struct pci_dev *pdev) {} > #ifdef CONFIG_PCIEPORTBUS > void pci_rcec_init(struct pci_dev *dev); > void pci_rcec_exit(struct pci_dev *dev); > +void pcie_link_rcec(struct pci_dev *rcec); > #else > static inline void pci_rcec_init(struct pci_dev *dev) {} > static inline void pci_rcec_exit(struct pci_dev *dev) {} > +static inline void pcie_link_rcec(struct pci_dev *rcec) {} > #endif > > #ifdef CONFIG_PCI_ATS > diff --git a/drivers/pci/pcie/portdrv_pci.c b/drivers/pci/pcie/portdrv_pci.c > index 4d880679b9b1..dbeb0155c2c3 100644 > --- a/drivers/pci/pcie/portdrv_pci.c > +++ b/drivers/pci/pcie/portdrv_pci.c > @@ -110,6 +110,9 @@ static int pcie_portdrv_probe(struct pci_dev *dev, > (pci_pcie_type(dev) != PCI_EXP_TYPE_RC_EC))) > return -ENODEV; > > + if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_EC) > + pcie_link_rcec(dev); > + > status = pcie_port_device_register(dev); > if (status) > return status; > diff --git a/drivers/pci/pcie/rcec.c b/drivers/pci/pcie/rcec.c > index 519ae086ff41..5630480a6659 100644 > --- a/drivers/pci/pcie/rcec.c > +++ b/drivers/pci/pcie/rcec.c > @@ -17,6 +17,102 @@ > > #include "../pci.h" > > +struct walk_rcec_data { > + struct pci_dev *rcec; > + int (*user_callback)(struct pci_dev *dev, void *data); > + void *user_data; > +}; > + > +static bool rcec_assoc_rciep(struct pci_dev *rcec, struct pci_dev *rciep) > +{ > + unsigned long bitmap = rcec->rcec_ext->bitmap; > + unsigned int devn; > + > + /* An RCiEP found on bus in range */ Perhaps adjust the comment to say: /* An RCiEP found on a different bus in range */ as the actual rcec bus can be in the range as I understand it. > + if (rcec->bus->number != rciep->bus->number) > + return true; > + > + /* Same bus, so check bitmap */ > + for_each_set_bit(devn, &bitmap, 32) > + if (devn == rciep->devfn) > + return true; > + > + return false; > +} > + > +static int link_rcec_helper(struct pci_dev *dev, void *data) > +{ > + struct walk_rcec_data *rcec_data = data; > + struct pci_dev *rcec = rcec_data->rcec; > + > + if ((pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END) && rcec_assoc_rciep(rcec, dev)) { > + dev->rcec = rcec; > + pci_dbg(dev, "PME & error events reported via %s\n", pci_name(rcec)); > + } > + > + return 0; > +} > + > +void walk_rcec(int (*cb)(struct pci_dev *dev, void *data), void *userdata) static, or declare it in a header if we are going to need it elsewhere later in the series. > +{ > + struct walk_rcec_data *rcec_data = userdata; > + struct pci_dev *rcec = rcec_data->rcec; > + u8 nextbusn, lastbusn; > + struct pci_bus *bus; > + unsigned int bnr; > + > + if (!rcec->rcec_cap) > + return; > + > + /* Walk own bus for bitmap based association */ > + pci_walk_bus(rcec->bus, cb, rcec_data); > + > + /* Check whether RCEC BUSN register is present */ > + if (rcec->rcec_ext->ver < PCI_RCEC_BUSN_REG_VER) > + return; If you make earlier suggested change go fill in nextbusn = 0xFF for the earlier versions of the capability can avoid special casing here. > + > + nextbusn = rcec->rcec_ext->nextbusn; > + lastbusn = rcec->rcec_ext->lastbusn; > + > + /* All RCiEP devices are on the same bus as the RCEC */ > + if (nextbusn == 0xff && lastbusn == 0x00) > + return; > + > + for (bnr = nextbusn; bnr <= lastbusn; bnr++) { > + /* No association indicated (PCIe 5.0-1, 7.9.10.3) */ > + if (bnr == rcec->bus->number) > + continue; > + > + bus = pci_find_bus(pci_domain_nr(rcec->bus), bnr); > + if (!bus) > + continue; > + > + /* Find RCiEP devices on the given bus ranges */ > + pci_walk_bus(bus, cb, rcec_data); > + } > +} > + > +/** > + * pcie_link_rcec - Link RCiEP devices associating with RCEC. > + * @rcec RCEC whose RCiEP devices should be linked. > + * > + * Link the given RCEC to each RCiEP device found. I'm a fusspot on blank lines. The one here doesn't add anything! > + * > + */ > +void pcie_link_rcec(struct pci_dev *rcec) > +{ > + struct walk_rcec_data rcec_data; > + > + if (!rcec->rcec_cap) > + return; > + > + rcec_data.rcec = rcec; > + rcec_data.user_callback = NULL; > + rcec_data.user_data = NULL; > + > + walk_rcec(link_rcec_helper, &rcec_data); > +} > + > void pci_rcec_init(struct pci_dev *dev) > { > u32 rcec, hdr, busn; > diff --git a/include/linux/pci.h b/include/linux/pci.h > index 5c5c4eb642b6..ad382a9484ea 100644 > --- a/include/linux/pci.h > +++ b/include/linux/pci.h > @@ -330,6 +330,7 @@ struct pci_dev { > #ifdef CONFIG_PCIEPORTBUS > u16 rcec_cap; /* RCEC capability offset */ > struct rcec_ext *rcec_ext; /* RCEC cached assoc. endpoint extended capabilities */ > + struct pci_dev *rcec; /* Associated RCEC device */ > #endif > u8 pcie_cap; /* PCIe capability offset */ > u8 msi_cap; /* MSI capability offset */