From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753567AbbJFREp (ORCPT ); Tue, 6 Oct 2015 13:04:45 -0400 Received: from foss.arm.com ([217.140.101.70]:53568 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753534AbbJFREl (ORCPT ); Tue, 6 Oct 2015 13:04:41 -0400 From: Marc Zyngier To: Rob Herring , Jason Cooper , Thomas Gleixner , Bjorn Helgaas Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-pci@vger.kernel.org, Mark Rutland , David Daney , Robin Murphy Subject: [PATCH v2 8/8] PCI/MSI: Allow the MSI domain to be device-specific Date: Tue, 6 Oct 2015 18:04:03 +0100 Message-Id: <1444151043-31084-9-git-send-email-marc.zyngier@arm.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1444151043-31084-1-git-send-email-marc.zyngier@arm.com> References: <1444151043-31084-1-git-send-email-marc.zyngier@arm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org So far, we've always considered that for a given PCI device, its MSI controller was either set by the architecture-specific pcibios hook, or simply inherited from the host bridge. This doesn't cover things like firmware-defined topologies like msi-map (DT) or IORT (ACPI), which can provide information about which MSI controller to use on a per-device basis. This patch adds the necessary hook into the MSI code to allow this feature, and provides the msi-map functionnality as a first implementation. Signed-off-by: Marc Zyngier --- drivers/pci/msi.c | 17 +++++++++++++++++ drivers/pci/probe.c | 8 ++++++++ include/linux/msi.h | 6 ++++++ 3 files changed, 31 insertions(+) diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 81a2798..3daff31 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -1357,4 +1357,21 @@ u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev) return rid; } + +/** + * pci_msi_get_device_domain - Get the MSI domain for a given PCI device + * @pdev: The PCI device + * + * Use the firmware data to find a device-specific MSI domain + * (i.e. not one that is ste as a default). + * + * Returns: The coresponding MSI domain or NULL if none has been found. + */ +struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev) +{ + u32 rid = 0; + + pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid); + return of_msi_map_get_device_domain(&pdev->dev, rid); +} #endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */ diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 7c333f8..f14a970 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1639,6 +1639,14 @@ static struct irq_domain *pci_dev_msi_domain(struct pci_dev *dev) if (d) return d; + /* + * Let's see if we have a firmware interface able to provide + * the domain. + */ + d = pci_msi_get_device_domain(dev); + if (d) + return d; + return NULL; } diff --git a/include/linux/msi.h b/include/linux/msi.h index 56e3b76..375be7c 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -294,6 +294,12 @@ irq_hw_number_t pci_msi_domain_calc_hwirq(struct pci_dev *dev, int pci_msi_domain_check_cap(struct irq_domain *domain, struct msi_domain_info *info, struct device *dev); u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev); +struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev); +#else +static inline struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev) +{ + return NULL; +} #endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */ #endif /* LINUX_MSI_H */ -- 2.1.4