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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DB34FC4332F for ; Fri, 11 Nov 2022 14:08:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234526AbiKKOIr (ORCPT ); Fri, 11 Nov 2022 09:08:47 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50012 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234661AbiKKOHU (ORCPT ); Fri, 11 Nov 2022 09:07:20 -0500 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 389458BAAE; Fri, 11 Nov 2022 06:00:05 -0800 (PST) Message-ID: <20221111135206.855773120@linutronix.de> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1668175136; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: references:references; bh=c9JDBZM977tVyvqvJg00lI013oKo3dOFRASxZv3UZ8g=; b=q2n47ka+68YaG2yfEg3JjMEqBvlfMw+HAAVmfrlUIzHf/hVn9tC4G73cZH4sgE7h/hFhjp qxr3IfDx24nO5xUGb25jZsF0uKHf179qiyWk6lnRbX9ILRvabBtWuvIOwXldNT9ZBboTTs PgdDqWxOIddAEFSFwb9SIv72XNuMb97d7jG9xpGK1Kf4xJsicv8HuVfpfsjCC5vffZ1jxj xGsZR88YLVNmL6HOn9Jk995+vgSrk+02/4prrg4niVOZMbiTPpuZa+1FT4amlFv4ihFRn9 LHfFmb8m13vorv94hbuxTzs8dTzTOjYSHaVvHAMRj/iOrf/KyUs0dVPhfV6xgQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1668175136; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: references:references; bh=c9JDBZM977tVyvqvJg00lI013oKo3dOFRASxZv3UZ8g=; b=g5YUbC+wZzhZLEQOjK7d4wtRAIdgARUsULHH+Sh+bi8sCZJAGFGrXCJgknnzYPLyDxVsDB LfqJdBHAqn2s+8Ag== From: Thomas Gleixner To: LKML Cc: x86@kernel.org, Joerg Roedel , Will Deacon , linux-pci@vger.kernel.org, Bjorn Helgaas , Lorenzo Pieralisi , Marc Zyngier , Greg Kroah-Hartman , Jason Gunthorpe , Dave Jiang , Alex Williamson , Kevin Tian , Dan Williams , Logan Gunthorpe , Ashok Raj , Jon Mason , Allen Hubbe , "Ahmed S. Darwish" , Reinette Chatre Subject: [patch 28/33] PCI/MSI: Provide IMS (Interrupt Message Store) support References: <20221111133158.196269823@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Date: Fri, 11 Nov 2022 14:58:55 +0100 (CET) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org IMS (Interrupt Message Store) is a new specification which allows implementation specific storage of MSI messages contrary to the strict standard specified MSI and MSI-X message stores. This requires new device specific interrupt domains to handle the implementation defined storage which can be an array in device memory or host/guest memory which is shared with hardware queues. Add a function to create IMS domains for PCI devices. IMS domains are using the new per device domain mechanism and are configured by the device driver via a template. IMS domains are created as secondary device domains so they work side on side with MSI[-X] on the same device. The IMS domains have a few constraints: - The index space is managed by the core code. Device memory based IMS provides a storage array with a fixed size which obviously requires an index. But there is no association between index and functionality so the core can randomly allocate an index in the array. Queue memory based IMS does not have the concept of an index as the storage is somewhere in memory. In that case the index is purely software based to keep track of the allocations. - There is no requirement for consecutive index ranges This is currently a limitation of the MSI core and can be implemented if there is a justified use case by changing the internal storage from xarray to maple_tree. For now it's single vector allocation. - The interrupt chip must provide the following callbacks: - irq_mask() - irq_unmask() - irq_write_msi_msg() - The interrupt chip must provide the following optional callbacks when the irq_mask(), irq_unmask() and irq_write_msi_msg() callbacks cannot operate directly on hardware, e.g. in the case that the interrupt message store is in queue memory: - irq_bus_lock() - irq_bus_unlock() These callbacks are invoked from preemptible task context and are allowed to sleep. In this case the mandatory callbacks above just store the information. The irq_bus_unlock() callback is supposed to make the change effective before returning. - Interrupt affinity setting is handled by the underlying parent interrupt domain and communicated to the IMS domain via irq_write_msi_msg(). IMS domains cannot have a irq_set_affinity() callback. That's a reasonable restriction similar to the PCI/MSI device domain implementations. The domain is automatically destroyed when the PCI device is removed. Signed-off-by: Thomas Gleixner --- drivers/pci/msi/irqdomain.c | 59 ++++++++++++++++++++++++++++++++++++++++++++ include/linux/pci.h | 5 +++ 2 files changed, 64 insertions(+) --- a/drivers/pci/msi/irqdomain.c +++ b/drivers/pci/msi/irqdomain.c @@ -355,6 +355,65 @@ bool pci_msi_domain_supports(struct pci_ return (supported & feature_mask) == feature_mask; } +/** + * pci_create_ims_domain - Create a secondary IMS domain for a PCI device + * @pdev: The PCI device to operate on + * @template: The MSI info template which describes the domain + * @hwsize: The size of the hardware entry table or 0 if the domain + * is purely software managed + * @data: Optional pointer to domain specific data to be stored + * in msi_domain_info::data + * + * Return: True on success, false otherwise + * + * A IMS domain is expected to have the following constraints: + * - The index space is managed by the core code + * + * - There is no requirement for consecutive index ranges + * + * - The interrupt chip must provide the following callbacks: + * - irq_mask() + * - irq_unmask() + * - irq_write_msi_msg() + * + * - The interrupt chip must provide the following optional callbacks + * when the irq_mask(), irq_unmask() and irq_write_msi_msg() callbacks + * cannot operate directly on hardware, e.g. in the case that the + * interrupt message store is in queue memory: + * - irq_bus_lock() + * - irq_bus_unlock() + * + * These callbacks are invoked from preemptible task context and are + * allowed to sleep. In this case the mandatory callbacks above just + * store the information. The irq_bus_unlock() callback is supposed + * to make the change effective before returning. + * + * - Interrupt affinity setting is handled by the underlying parent + * interrupt domain and communicated to the IMS domain via + * irq_write_msi_msg(). + * + * The domain is automatically destroyed when the PCI device is removed. + */ +bool pci_create_ims_domain(struct pci_dev *pdev, const struct msi_domain_template *template, + unsigned int hwsize, void *data) +{ + struct irq_domain *domain = dev_get_msi_domain(&pdev->dev); + + if (!domain || !irq_domain_is_msi_parent(domain)) + return -ENOTSUPP; + + if (template->info.bus_token != DOMAIN_BUS_PCI_DEVICE_IMS || + !(template->info.flags & MSI_FLAG_ALLOC_SIMPLE_MSI_DESCS) || + !(template->info.flags & MSI_FLAG_FREE_MSI_DESCS) || + !template->chip.irq_mask || !template->chip.irq_unmask || + !template->chip.irq_write_msi_msg || template->chip.irq_set_affinity) + return -EINVAL; + + return msi_create_device_irq_domain(&pdev->dev, MSI_SECONDARY_DOMAIN, template, + hwsize, data, NULL); +} +EXPORT_SYMBOL_GPL(pci_create_ims_domain); + /* * Users of the generic MSI infrastructure expect a device to have a single ID, * so with DMA aliases we have to pick the least-worst compromise. Devices with --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -2481,6 +2481,11 @@ static inline bool pci_is_thunderbolt_at void pci_uevent_ers(struct pci_dev *pdev, enum pci_ers_result err_type); #endif +struct msi_domain_template; + +bool pci_create_ims_domain(struct pci_dev *pdev, const struct msi_domain_template *template, + unsigned int hwsize, void *data); + #include #define pci_printk(level, pdev, fmt, arg...) \