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_1 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 DF49CC433E0 for ; Sat, 11 Jul 2020 21:45:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ADDE92077D for ; Sat, 11 Jul 2020 21:45:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726948AbgGKVpS (ORCPT ); Sat, 11 Jul 2020 17:45:18 -0400 Received: from mga09.intel.com ([134.134.136.24]:4471 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726281AbgGKVpS (ORCPT ); Sat, 11 Jul 2020 17:45:18 -0400 IronPort-SDR: IGIGpwABWFTmBsr3RBJbqvrSv4VWSOLuRuq5k2jTPLliLR2674m/0qjGKJ/4CkCyGwf7pELs6e 4XQETjLeXUrA== X-IronPort-AV: E=McAfee;i="6000,8403,9679"; a="149903429" X-IronPort-AV: E=Sophos;i="5.75,341,1589266800"; d="scan'208";a="149903429" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Jul 2020 14:45:17 -0700 IronPort-SDR: IwKLLPRqS4CYlJbcYhqSY6sGQUINUKW8NxDufdHH24CCO9Dpalbw/qxoTC50wDFZNpDOJI8jrc jUg2A3UAmj2A== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.75,341,1589266800"; d="scan'208";a="269375260" Received: from nholling-mobl.amr.corp.intel.com (HELO [10.251.10.249]) ([10.251.10.249]) by fmsmga008.fm.intel.com with ESMTP; 11 Jul 2020 14:45:16 -0700 Subject: Re: [PATCH v6 1/4] ACPI/PCI: Ignore _OSC negotiation result if pcie_ports_native is set. To: Bjorn Helgaas Cc: bhelgaas@google.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, ashok.raj@intel.com References: <20200709230716.GA23972@bjorn-Precision-5520> From: "Kuppuswamy, Sathyanarayanan" Message-ID: <02f2c538-c192-65d3-75ec-7874436b966c@linux.intel.com> Date: Sat, 11 Jul 2020 14:45:16 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: <20200709230716.GA23972@bjorn-Precision-5520> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Hi Bjorn, On 7/9/20 4:07 PM, Bjorn Helgaas wrote: > On Fri, Jun 26, 2020 at 11:32:33AM -0700, sathyanarayanan.kuppuswamy@linux.intel.com wrote: >> From: Kuppuswamy Sathyanarayanan >> >> pcie_ports_native is set only if user requests native handling >> of PCIe capabilities via pcie_port_setup command line option. >> User input takes precedence over _OSC based control negotiation >> result. So consider the _OSC negotiated result only if >> pcie_ports_native is unset. >> >> Also, since struct pci_host_bridge ->native_* members caches the >> ownership status of various PCIe capabilities, use them instead >> of distributed checks for pcie_ports_native. >> >> Signed-off-by: Kuppuswamy Sathyanarayanan >> --- >> drivers/acpi/pci_root.c | 26 ++++++++++++++------------ >> drivers/pci/hotplug/pciehp_core.c | 2 +- >> drivers/pci/pci-acpi.c | 3 --- >> drivers/pci/pcie/aer.c | 2 +- >> drivers/pci/pcie/portdrv_core.c | 9 +++------ >> drivers/pci/probe.c | 5 +++-- >> 6 files changed, 22 insertions(+), 25 deletions(-) >> >> diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c >> index f90e841c59f5..02fab8b0118e 100644 >> --- a/drivers/acpi/pci_root.c >> +++ b/drivers/acpi/pci_root.c >> @@ -914,18 +914,20 @@ struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root, >> goto out_release_info; >> >> host_bridge = to_pci_host_bridge(bus->bridge); >> - if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL)) >> - host_bridge->native_pcie_hotplug = 0; >> - if (!(root->osc_control_set & OSC_PCI_SHPC_NATIVE_HP_CONTROL)) >> - host_bridge->native_shpc_hotplug = 0; >> - if (!(root->osc_control_set & OSC_PCI_EXPRESS_AER_CONTROL)) >> - host_bridge->native_aer = 0; >> - if (!(root->osc_control_set & OSC_PCI_EXPRESS_PME_CONTROL)) >> - host_bridge->native_pme = 0; >> - if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL)) >> - host_bridge->native_ltr = 0; >> - if (!(root->osc_control_set & OSC_PCI_EXPRESS_DPC_CONTROL)) >> - host_bridge->native_dpc = 0; >> + if (!pcie_ports_native) { >> + if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL)) >> + host_bridge->native_pcie_hotplug = 0; >> + if (!(root->osc_control_set & OSC_PCI_SHPC_NATIVE_HP_CONTROL)) >> + host_bridge->native_shpc_hotplug = 0; >> + if (!(root->osc_control_set & OSC_PCI_EXPRESS_AER_CONTROL)) >> + host_bridge->native_aer = 0; >> + if (!(root->osc_control_set & OSC_PCI_EXPRESS_PME_CONTROL)) >> + host_bridge->native_pme = 0; >> + if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL)) >> + host_bridge->native_ltr = 0; >> + if (!(root->osc_control_set & OSC_PCI_EXPRESS_DPC_CONTROL)) >> + host_bridge->native_dpc = 0; >> + } > > When the user boots with "pcie_ports=native", should we evaluate _OSC > at all? Since pcie_ports="native" does not override OSC_PCI_SHPC_NATIVE_HP_CONTROL, I think we should still evaluate _OSC. Also firmware might still wants to know about supported features during _OSC call. It seems confusing to say "OK, Mr. Firmware, here are the > features we want to use", and then turn around and use them all > regardless of what the platform said. Why not just ignore the > firmware completely and go ahead and use everything?| AFAIK, for PCIe features, It should functionally make no difference (evaluating _OSC vs not). But, IMO, its useful if we print some warnings if firmware denies some of the PCIe feature control. > > I can't remember if there's a reason we need to call > negotiate_os_control() so early and then hang on to the results until > we get here: > > acpi_pci_root_add > negotiate_os_control <--- eval _OSC > pci_acpi_scan_root > acpi_pci_root_create > pci_create_root_bus > if (!(root->osc_control_set & ...)) <--- use results > host_bridge->native_... = 0; > > I think it would be a lot simpler if we could do the _OSC negotiation > right here where we need most of the results. It would be even better > if we could update the host_bridge->native_... items directly inside > negotiate_os_control() so we wouldn't have to hang onto the > osc_control_set mask. Makes sense. I also don't see any one use _OSC negotiated results until pci_create_root_bus(). But I think this should be a seperate patch. > >> /* >> * Evaluate the "PCI Boot Configuration" _DSM Function. If it >> diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c >> index bf779f291f15..5fc999bf6f1b 100644 >> --- a/drivers/pci/hotplug/pciehp_core.c >> +++ b/drivers/pci/hotplug/pciehp_core.c >> @@ -255,7 +255,7 @@ static bool pme_is_native(struct pcie_device *dev) >> const struct pci_host_bridge *host; >> >> host = pci_find_host_bridge(dev->port->bus); >> - return pcie_ports_native || host->native_pme; >> + return host->native_pme; >> } >> >> static void pciehp_disable_interrupt(struct pcie_device *dev) >> diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c >> index 7224b1e5f2a8..e09589571a9d 100644 >> --- a/drivers/pci/pci-acpi.c >> +++ b/drivers/pci/pci-acpi.c >> @@ -800,9 +800,6 @@ bool pciehp_is_native(struct pci_dev *bridge) >> if (!(slot_cap & PCI_EXP_SLTCAP_HPC)) >> return false; >> >> - if (pcie_ports_native) >> - return true; >> - >> host = pci_find_host_bridge(bridge->bus); >> return host->native_pcie_hotplug; >> } >> diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c >> index 3acf56683915..d663bd9c7257 100644 >> --- a/drivers/pci/pcie/aer.c >> +++ b/drivers/pci/pcie/aer.c >> @@ -219,7 +219,7 @@ int pcie_aer_is_native(struct pci_dev *dev) >> if (!dev->aer_cap) >> return 0; >> >> - return pcie_ports_native || host->native_aer; >> + return host->native_aer; >> } >> >> int pci_enable_pcie_error_reporting(struct pci_dev *dev) >> diff --git a/drivers/pci/pcie/portdrv_core.c b/drivers/pci/pcie/portdrv_core.c >> index 50a9522ab07d..ccd5e0ce5605 100644 >> --- a/drivers/pci/pcie/portdrv_core.c >> +++ b/drivers/pci/pcie/portdrv_core.c >> @@ -208,8 +208,7 @@ static int get_port_device_capability(struct pci_dev *dev) >> struct pci_host_bridge *host = pci_find_host_bridge(dev->bus); >> int services = 0; >> >> - if (dev->is_hotplug_bridge && >> - (pcie_ports_native || host->native_pcie_hotplug)) { >> + if (dev->is_hotplug_bridge && host->native_pcie_hotplug) { >> services |= PCIE_PORT_SERVICE_HP; >> >> /* >> @@ -221,8 +220,7 @@ static int get_port_device_capability(struct pci_dev *dev) >> } >> >> #ifdef CONFIG_PCIEAER >> - if (dev->aer_cap && pci_aer_available() && >> - (pcie_ports_native || host->native_aer)) { >> + if (dev->aer_cap && pci_aer_available() && host->native_aer) { >> services |= PCIE_PORT_SERVICE_AER; >> >> /* >> @@ -238,8 +236,7 @@ static int get_port_device_capability(struct pci_dev *dev) >> * Event Collectors can also generate PMEs, but we don't handle >> * those yet. >> */ >> - if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT && >> - (pcie_ports_native || host->native_pme)) { >> + if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT && host->native_pme) { >> services |= PCIE_PORT_SERVICE_PME; > > I *love* that you removed pcie_ports_native from all these places. > >> /* >> diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c >> index 2f66988cea25..5fb90bb9b4e3 100644 >> --- a/drivers/pci/probe.c >> +++ b/drivers/pci/probe.c >> @@ -588,13 +588,14 @@ static void pci_init_host_bridge(struct pci_host_bridge *bridge) >> * may implement its own AER handling and use _OSC to prevent the >> * OS from interfering. >> */ >> +#ifdef CONFIG_PCIEPORTBUS >> bridge->native_aer = 1; >> bridge->native_pcie_hotplug = 1; >> - bridge->native_shpc_hotplug = 1; >> bridge->native_pme = 1; >> bridge->native_ltr = 1; >> bridge->native_dpc = 1; >> - >> +#endif >> + bridge->native_shpc_hotplug = 1; > > This looks like a bugfix that should be its own patch. Agreed. I will split it in next version. > >> device_initialize(&bridge->dev); >> } >> >> -- >> 2.17.1 >> -- Sathyanarayanan Kuppuswamy Linux Kernel Developer