From mboxrd@z Thu Jan 1 00:00:00 1970 From: Liviu Dudau Subject: Re: [Patch v7 4/7] PCI/ACPI: Add interface acpi_pci_root_create() Date: Wed, 21 Oct 2015 12:52:24 +0100 Message-ID: <20151021115224.GH3394@e106497-lin.cambridge.arm.com> References: <1444804182-6596-1-git-send-email-jiang.liu@linux.intel.com> <1444804182-6596-5-git-send-email-jiang.liu@linux.intel.com> <562761A1.4020306@linaro.org> <20151021110201.GE3394@e106497-lin.cambridge.arm.com> <562776A5.7000303@linaro.org> <56277BB9.8090508@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from foss.arm.com ([217.140.101.70]:60657 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932211AbbJULw0 (ORCPT ); Wed, 21 Oct 2015 07:52:26 -0400 Content-Disposition: inline In-Reply-To: <56277BB9.8090508@linux.intel.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Jiang Liu Cc: Tomasz Nowicki , Bjorn Helgaas , "Rafael J . Wysocki" , Lorenzo Pieralisi , Marc Zyngier , Hanjun Guo , linux-acpi@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, x86@kernel.org On Wed, Oct 21, 2015 at 07:49:13PM +0800, Jiang Liu wrote: > On 2015/10/21 19:27, Tomasz Nowicki wrote: > > On 21.10.2015 13:02, Liviu Dudau wrote: > >> On Wed, Oct 21, 2015 at 11:57:53AM +0200, Tomasz Nowicki wrote: > >>> On 14.10.2015 08:29, Jiang Liu wrote: > >>>> Introduce common interface acpi_pci_root_create() and related da= ta > >>>> structures to create PCI root bus for ACPI PCI host bridges. It = will > >>>> be used to kill duplicated arch specific code for IA64 and x86. = It may > >>>> also help ARM64 in future. > >>>> > >>>> Reviewed-by: Lorenzo Pieralisi > >>>> Tested-by: Tony Luck > >>>> Signed-off-by: Jiang Liu > >>>> Signed-off-by: Liu Jiang > >>>> --- > >>>> drivers/acpi/pci_root.c | 204 > >>>> ++++++++++++++++++++++++++++++++++++++++++++++ > >>>> include/linux/pci-acpi.h | 24 ++++++ > >>>> 2 files changed, 228 insertions(+) > >>>> > >>> > >>> [...] > >>> > >>>> + > >>>> +struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root= , > >>>> + struct acpi_pci_root_ops *ops, > >>>> + struct acpi_pci_root_info *info, > >>>> + void *sysdata) > >>>> +{ > >>>> + int ret, busnum =3D root->secondary.start; > >>>> + struct acpi_device *device =3D root->device; > >>>> + int node =3D acpi_get_node(device->handle); > >>>> + struct pci_bus *bus; > >>>> + > >>>> + info->root =3D root; > >>>> + info->bridge =3D device; > >>>> + info->ops =3D ops; > >>>> + INIT_LIST_HEAD(&info->resources); > >>>> + snprintf(info->name, sizeof(info->name), "PCI Bus %04x:%02x= ", > >>>> + root->segment, busnum); > >>>> + > >>>> + if (ops->init_info && ops->init_info(info)) > >>>> + goto out_release_info; > >>>> + if (ops->prepare_resources) > >>>> + ret =3D ops->prepare_resources(info); > >>>> + else > >>>> + ret =3D acpi_pci_probe_root_resources(info); > >>>> + if (ret < 0) > >>>> + goto out_release_info; > >>>> + > >>>> + pci_acpi_root_add_resources(info); > >>>> + pci_add_resource(&info->resources, &root->secondary); > >>>> + bus =3D pci_create_root_bus(NULL, busnum, ops->pci_ops, > >>>> + sysdata, &info->resources); > >>> > >>> Thank a lot for this cleanup!! > >>> > >>> I recall you already considered passing segment (domain nr) to > >>> pci_create_root_bus, right? Can you please remind me why we gave = up > >>> on this? > >>> > >>> I am asking because currently I can not find the way to retrieve = domain > >>> number from pci_bus_assign_domain_nr (for those platforms which c= hoose > >>> PCI_DOMAINS_GENERIC and want to use segment nr from MCFG table) w= hich > >>> is the > >>> part of pci_create_root_bus. > >> > >> Not sure I fully understand your question, but > >> pci_bus_assign_domain_nr() will > >> put the assigned domain number in bus->domain_nr if you chose > >> PCI_DOMAINS_GENERIC. > >> Do you want to override that value with the segment nr from MCFG? > >> > >=20 > > Let me give ACPI ARM64 example: > >=20 > > 1. We parse MCFG table and get segment nr assigned to root bridge > > 2. Then PCI host bridge calls acpi_pci_root_create -> > > pci_create_root_bus -> pci_bus_assign_domain_nr > > 3. At this point we cannot get segment nr for ACPI > >=20 > > So I would like to assign MCFG segment nr to bus->domain_nr being i= n > > pci_bus_assign_domain_nr giving we have scenario above. > Please use sysdata for that, IA64 and x86 are making use of sysdata > to store such information: > struct pci_sysdata { > int domain; /* PCI domain */ > int node; /* NUMA node */ > #ifdef CONFIG_ACPI > struct acpi_device *companion; /* ACPI companion device */ > #endif > #ifdef CONFIG_X86_64 > void *iommu; /* IOMMU private data */ > #endif > }; >=20 > Hanjun once tried to introduce struct pci_sysdata for ARM64, but > seems it has been rejected. =46or good reason! There is a lot of duplication between different arch= es notion of the pci_sysdata and they can be moved into pci_bus or pci_host_bridg= e structures. The goal is to get rid of multiple pci_sysdata structures, = not to add more. Best regards, Liviu >=20 > >=20 > > Thanks, > > Tomasz > > --=20 > > To unsubscribe from this list: send the line "unsubscribe linux-ker= nel" in > > the body of a message to majordomo@vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > Please read the FAQ at http://www.tux.org/lkml/ >=20 --=20 =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D | I would like to | | fix the world, | | but they're not | | giving me the | \ source code! / --------------- =C2=AF\_(=E3=83=84)_/=C2=AF -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html