From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1424784AbcFMPrY (ORCPT ); Mon, 13 Jun 2016 11:47:24 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:56402 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1424144AbcFMPrW (ORCPT ); Mon, 13 Jun 2016 11:47:22 -0400 Subject: Re: [RFC PATCH V2 1/2] ACPI/PCI: Match PCI config space accessors against platfrom specific ECAM quirks To: Dongdong Liu , helgaas@kernel.org, arnd@arndb.de, will.deacon@arm.com, catalin.marinas@arm.com, rafael@kernel.org, hanjun.guo@linaro.org, Lorenzo.Pieralisi@arm.com, okaya@codeaurora.org, jchandra@broadcom.com, tn@semihalf.com References: <1465822923-33599-1-git-send-email-liudongdong3@huawei.com> <1465822923-33599-2-git-send-email-liudongdong3@huawei.com> Cc: robert.richter@caviumnetworks.com, mw@semihalf.com, Liviu.Dudau@arm.com, ddaney@caviumnetworks.com, wangyijing@huawei.com, Suravee.Suthikulpanit@amd.com, msalter@redhat.com, linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, linaro-acpi@lists.linaro.org, jcm@redhat.com, andrea.gallo@linaro.org, dhdang@apm.com, jeremy.linton@arm.com, gabriele.paoloni@huawei.com, charles.chenxin@huawei.com, linuxarm@huawei.com From: Christopher Covington Message-ID: <575ED57F.6050503@codeaurora.org> Date: Mon, 13 Jun 2016 11:47:11 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:43.0) Gecko/20100101 Thunderbird/43.0 MIME-Version: 1.0 In-Reply-To: <1465822923-33599-2-git-send-email-liudongdong3@huawei.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Dongdong, On 06/13/2016 09:02 AM, Dongdong Liu wrote: > diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c > index d3c3e85..49612b3 100644 > --- a/drivers/acpi/pci_mcfg.c > +++ b/drivers/acpi/pci_mcfg.c > @@ -22,6 +22,10 @@ > #include > #include > #include > +#include > + > +/* Root pointer to the mapped MCFG table */ > +static struct acpi_table_mcfg *mcfg_table; > > /* Structure to hold entries from the MCFG table */ > struct mcfg_entry { > @@ -35,6 +39,38 @@ struct mcfg_entry { > /* List to save mcfg entries */ > static LIST_HEAD(pci_mcfg_list); > > +extern struct pci_cfg_fixup __start_acpi_mcfg_fixups[]; > +extern struct pci_cfg_fixup __end_acpi_mcfg_fixups[]; > + > +struct pci_ecam_ops *pci_mcfg_get_ops(struct acpi_pci_root *root) > +{ > + int bus_num = root->secondary.start; > + int domain = root->segment; > + struct pci_cfg_fixup *f; > + > + if (!mcfg_table) > + return &pci_generic_ecam_ops; > + > + /* > + * Match against platform specific quirks and return corresponding > + * CAM ops. > + * > + * First match against PCI topology then use OEM ID and > + * OEM revision from MCFG table standard header. > + */ > + for (f = __start_acpi_mcfg_fixups; f < __end_acpi_mcfg_fixups; f++) { > + if ((f->domain == domain || f->domain == PCI_MCFG_DOMAIN_ANY) && > + (f->bus_num == bus_num || f->bus_num == PCI_MCFG_BUS_ANY) && > + (!strncmp(f->oem_id, mcfg_table->header.oem_id, > + ACPI_OEM_ID_SIZE)) && > + (!strncmp(f->oem_table_id, mcfg_table->header.oem_table_id, > + ACPI_OEM_TABLE_ID_SIZE))) This would just be a small convenience, but if the character count used here were min(strlen(f->oem_id), ACPI_OEM_ID_SIZE) then the parameters to DECLARE_ACPI_MCFG_FIXUP macro could be substrings and wouldn't need to be padded out to the full length. > + return f->ops; > + } > + /* No quirks, use ECAM */ > + return &pci_generic_ecam_ops; > +} > diff --git a/include/linux/pci-acpi.h b/include/linux/pci-acpi.h > index 7d63a66..088a1da 100644 > --- a/include/linux/pci-acpi.h > +++ b/include/linux/pci-acpi.h > @@ -25,6 +25,7 @@ static inline acpi_status pci_acpi_remove_pm_notifier(struct acpi_device *dev) > extern phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle); > > extern phys_addr_t pci_mcfg_lookup(u16 domain, struct resource *bus_res); > +extern struct pci_ecam_ops *pci_mcfg_get_ops(struct acpi_pci_root *root); > > static inline acpi_handle acpi_find_root_bridge_handle(struct pci_dev *pdev) > { > @@ -72,6 +73,25 @@ struct acpi_pci_root_ops { > int (*prepare_resources)(struct acpi_pci_root_info *info); > }; > > +struct pci_cfg_fixup { > + struct pci_ecam_ops *ops; > + char *oem_id; > + char *oem_table_id; > + int domain; > + int bus_num; > +}; > + > +#define PCI_MCFG_DOMAIN_ANY -1 > +#define PCI_MCFG_BUS_ANY -1 > + > +/* Designate a routine to fix up buggy MCFG */ > +#define DECLARE_ACPI_MCFG_FIXUP(ops, oem_id, oem_table_id, dom, bus) \ > + static const struct pci_cfg_fixup \ > + __mcfg_fixup_##oem_id##oem_table_id##dom##bus \ I'm not entirely sure that this is the right fix--I'm pretty blindly following a GCC documentation suggestion [1]--but removing the first two preprocessor concatenation operators "##" solved the following build error for me. include/linux/pci-acpi.h:90:2: error: pasting "__mcfg_fixup_" and ""QCOM"" does not give a valid preprocessing token __mcfg_fixup_##oem_id##oem_table_id##dom##bus \ ^ arch/arm64/kernel/pci.c:225:1: note: in expansion of macro ‘DECLARE_ACPI_MCFG_FIXUP’ DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432", PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY); ^ arch/arm64/kernel/pci.c:225:44: error: pasting ""QCOM"" and ""QDF2432"" does not give a valid preprocessing token DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432", PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY); ^ include/linux/pci-acpi.h:90:17: note: in definition of macro ‘DECLARE_ACPI_MCFG_FIXUP’ __mcfg_fixup_##oem_id##oem_table_id##dom##bus \ ^ arch/arm64/kernel/pci.c:225:52: error: pasting ""QDF2432"" and "PCI_MCFG_DOMAIN_ANY" does not give a valid preprocessi ng token DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432", PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY); ^ include/linux/pci-acpi.h:90:25: note: in definition of macro ‘DECLARE_ACPI_MCFG_FIXUP’ __mcfg_fixup_##oem_id##oem_table_id##dom##bus \ ^ arch/arm64/kernel/pci.c:225:44: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before string constant DECLARE_ACPI_MCFG_FIXUP(&pci_32b_ecam_ops, "QCOM", "QDF2432", PCI_MCFG_DOMAIN_ANY, PCI_MCFG_BUS_ANY); ^ include/linux/pci-acpi.h:90:17: note: in definition of macro ‘DECLARE_ACPI_MCFG_FIXUP’ __mcfg_fixup_##oem_id##oem_table_id##dom##bus \ ^ make[1]: *** [arch/arm64/kernel/pci.o] Error 1 make: *** [arch/arm64/kernel] Error 2 1. https://gcc.gnu.org/onlinedocs/cpp/Concatenation.html#Concatenation > + __used __attribute__((__section__(".acpi_fixup_mcfg"), \ > + aligned((sizeof(void *))))) = \ > + { ops, oem_id, oem_table_id, dom, bus }; > + > extern int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info); > extern struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root, > struct acpi_pci_root_ops *ops, > Thanks, Cov -- Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project