Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751759AbaLXWMw (ORCPT ); Wed, 24 Dec 2014 17:12:52 -0500 Received: from devils.ext.ti.com ([198.47.26.153]:43038 "EHLO devils.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751858AbaLXWMX (ORCPT ); Wed, 24 Dec 2014 17:12:23 -0500 From: Murali Karicheri To: , , , , , , , , , CC: Murali Karicheri Subject: [PATCH v2 1/2] of/pci: add of_pci_dma_configure() update dma configuration Date: Wed, 24 Dec 2014 17:11:38 -0500 Message-ID: <1419459099-6667-2-git-send-email-m-karicheri2@ti.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1419459099-6667-1-git-send-email-m-karicheri2@ti.com> References: <1419459099-6667-1-git-send-email-m-karicheri2@ti.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add of_pci_dma_configure() to allow updating the dma configuration of the pci device using the configuration from DT of the parent of the root bridge device. Signed-off-by: Murali Karicheri --- drivers/of/of_pci.c | 73 ++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/of_pci.h | 12 ++++++++ 2 files changed, 85 insertions(+) diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c index 88471d3..6d43f59 100644 --- a/drivers/of/of_pci.c +++ b/drivers/of/of_pci.c @@ -229,6 +229,79 @@ parse_failed: return err; } EXPORT_SYMBOL_GPL(of_pci_get_host_bridge_resources); + +/** + * of_get_pci_root_bridge_parent - Helper function to get the OF node of + * the root bridge's parent + * @dev: ptr to pci_dev struct of the pci device + * + * This function will traverse the bus up to the root bus starting with + * the child and return the of node ptr to bridge device's parent device. + */ +struct device_node *of_get_pci_root_bridge_parent(struct pci_dev *dev) +{ + struct pci_bus *bus = dev->bus; + struct device *bridge; + + while (!pci_is_root_bus(bus)) + bus = bus->parent; + bridge = bus->bridge; + + return bridge->parent->of_node; +} +EXPORT_SYMBOL_GPL(of_get_pci_root_bridge_parent); + +/** + * of_pci_dma_configure - Setup DMA configuration + * @dev: ptr to pci_dev struct of the pci device + * + * Try to get PCI devices's DMA configuration from DT and update it + * accordingly. This is similar to of_dma_configure() in of/platform.c + */ +void of_pci_dma_configure(struct pci_dev *pci_dev) +{ + struct device *dev = &pci_dev->dev; + u64 dma_addr, paddr, size; + struct device_node *parent_np; + unsigned long offset; + bool coherent; + int ret; + + parent_np = of_get_pci_root_bridge_parent(pci_dev); + + if (parent_np) { + /* + * Set default dma-mask to 32 bit. Drivers are expected to setup + * the correct supported dma_mask. + */ + dev->coherent_dma_mask = DMA_BIT_MASK(32); + + /* + * Set it to coherent_dma_mask by default if the architecture + * code has not set it. + */ + if (!dev->dma_mask) + dev->dma_mask = &dev->coherent_dma_mask; + + ret = of_dma_get_range(parent_np, &dma_addr, &paddr, &size); + if (ret < 0) { + dma_addr = offset = 0; + size = dev->coherent_dma_mask + 1; + } else { + offset = PFN_DOWN(paddr - dma_addr); + dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset); + } + dev->dma_pfn_offset = offset; + + coherent = of_dma_is_coherent(parent_np); + dev_dbg(dev, "device is%sdma coherent\n", + coherent ? " " : " not "); + + arch_setup_dma_ops(dev, dma_addr, size, NULL, coherent); + } +} +EXPORT_SYMBOL_GPL(of_pci_dma_configure); + #endif /* CONFIG_OF_ADDRESS */ #ifdef CONFIG_PCI_MSI diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h index ce0e5ab..0465a2a 100644 --- a/include/linux/of_pci.h +++ b/include/linux/of_pci.h @@ -16,6 +16,8 @@ int of_pci_get_devfn(struct device_node *np); int of_irq_parse_and_map_pci(const struct pci_dev *dev, u8 slot, u8 pin); int of_pci_parse_bus_range(struct device_node *node, struct resource *res); int of_get_pci_domain_nr(struct device_node *node); +struct device_node *of_get_pci_root_bridge_parent(struct pci_dev *dev); +void of_pci_dma_configure(struct pci_dev *pci_dev); #else static inline int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq) { @@ -50,6 +52,16 @@ of_get_pci_domain_nr(struct device_node *node) { return -1; } + +static inline struct device_node +*of_get_pci_root_bridge_parent(struct pci_dev *dev) +{ + return NULL; +} + +static inline void of_pci_dma_configure(struct pci_dev *pci_dev) +{ +} #endif #if defined(CONFIG_OF_ADDRESS) -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" 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/