From patchwork Wed Dec 12 16:37:50 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Murray X-Patchwork-Id: 205577 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 192D62C0087 for ; Thu, 13 Dec 2012 03:38:11 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754734Ab2LLQhz (ORCPT ); Wed, 12 Dec 2012 11:37:55 -0500 Received: from service87.mimecast.com ([91.220.42.44]:40781 "EHLO service87.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754472Ab2LLQhy convert rfc822-to-8bit (ORCPT ); Wed, 12 Dec 2012 11:37:54 -0500 Received: from cam-owa2.Emea.Arm.com (fw-tnat.cambridge.arm.com [217.140.96.21]) by service87.mimecast.com; Wed, 12 Dec 2012 16:37:52 +0000 Received: from arm.com ([10.1.255.212]) by cam-owa2.Emea.Arm.com with Microsoft SMTPSVC(6.0.3790.3959); Wed, 12 Dec 2012 16:37:50 +0000 Date: Wed, 12 Dec 2012 16:37:50 +0000 From: Andrew Murray To: linux-pci@vger.kernel.org Cc: Thierry Reding , Grant Likely , Michal Simek , Rob Herring , devicetree-discuss , Rob Herring , linuxppc-dev , Benjamin Herrenschmidt , Liviu Dudau Subject: [PATCH] pci: Provide support for parsing PCI DT ranges property Message-ID: <20121212163749.GA17371@arm.com> MIME-Version: 1.0 User-Agent: Mutt/1.5.20 (2009-06-14) X-OriginalArrivalTime: 12 Dec 2012 16:37:51.0022 (UTC) FILETIME=[06D1F4E0:01CDD887] X-MC-Unique: 112121216375201301 Content-Disposition: inline Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org DT bindings for PCI host bridges often use the ranges property to describe memory and IO ranges - this binding tends to be the same across architectures yet several parsing implementations exist, e.g. arch/mips/pci/pci.c, arch/powerpc/kernel/pci-common.c, arch/sparc/kernel/pci.c and arch/microblaze/pci/pci-common.c (clone of PPC). Some of these duplicate functionality provided by drivers/of/address.c. This patch provides a common iterator-based parser for the ranges property, it is hoped this will reduce DT representation differences between architectures and that architectures will migrate in part to this new parser. It is also hoped (and the motativation for the patch) that this patch will reduce duplication of code when writing host bridge drivers that are supported by multiple architectures. This patch provides struct resources from a device tree node, e.g.: u32 *last = NULL; struct resource res; while ((last = of_pci_process_ranges(np, res, last))) { //do something with res } Platforms with quirks can then do what they like with the resource or migrate common quirk handling to the parser. In an ideal world drivers can just request the obtained resources and pass them on (e.g. pci_add_resource_offset). Signed-off-by: Andrew Murray Signed-off-by: Liviu Dudau --- drivers/of/address.c | 53 +++++++++++++++++++++++++++++++++++++++++++- include/linux/of_address.h | 7 +++++ 2 files changed, 59 insertions(+), 1 deletions(-) diff --git a/drivers/of/address.c b/drivers/of/address.c index 7e262a6..03bfe61 100644 --- a/drivers/of/address.c +++ b/drivers/of/address.c @@ -219,6 +219,57 @@ int of_pci_address_to_resource(struct device_node *dev, int bar, return __of_address_to_resource(dev, addrp, size, flags, NULL, r); } EXPORT_SYMBOL_GPL(of_pci_address_to_resource); + +const __be32 *of_pci_process_ranges(struct device_node *node, + struct resource *res, const __be32 *from) +{ + const __be32 *start, *end; + int na, ns, np, pna; + int rlen; + struct of_bus *bus; + WARN_ON(!res); + + bus = of_match_bus(node); + bus->count_cells(node, &na, &ns); + if (!OF_CHECK_COUNTS(na, ns)) { + pr_err("Bad cell count for %s\n", node->full_name); + return NULL; + } + + pna = of_n_addr_cells(node); + np = pna + na + ns; + + start = of_get_property(node, "ranges", &rlen); + if (start == NULL) + return NULL; + + end = start + rlen; + + if (!from) + from = start; + + while (from + np <= end) { + u64 cpu_addr, size; + + cpu_addr = of_translate_address(node, from + na); + size = of_read_number(from + na + pna, ns); + res->flags = bus->get_flags(from); + from += np; + + if (cpu_addr == OF_BAD_ADDR || size == 0) + continue; + + res->name = node->full_name; + res->start = cpu_addr; + res->end = res->start + size - 1; + res->parent = res->child = res->sibling = NULL; + return from; + } + + return NULL; +} +EXPORT_SYMBOL_GPL(of_pci_process_ranges); + #endif /* CONFIG_PCI */ /* @@ -421,7 +472,7 @@ u64 __of_translate_address(struct device_node *dev, const __be32 *in_addr, goto bail; bus = of_match_bus(parent); - /* Cound address cells & copy address locally */ + /* Count address cells & copy address locally */ bus->count_cells(dev, &na, &ns); if (!OF_CHECK_COUNTS(na, ns)) { printk(KERN_ERR "prom_parse: Bad cell count for %s\n", diff --git a/include/linux/of_address.h b/include/linux/of_address.h index 01b925a..4582b20 100644 --- a/include/linux/of_address.h +++ b/include/linux/of_address.h @@ -26,6 +26,8 @@ static inline unsigned long pci_address_to_pio(phys_addr_t addr) { return -1; } #define pci_address_to_pio pci_address_to_pio #endif +const __be32 *of_pci_process_ranges(struct device_node *node, + struct resource *res, const __be32 *from); #else /* CONFIG_OF_ADDRESS */ static inline int of_address_to_resource(struct device_node *dev, int index, struct resource *r) @@ -48,6 +50,11 @@ static inline const u32 *of_get_address(struct device_node *dev, int index, { return NULL; } +const __be32 *of_pci_process_ranges(struct device_node *node, + struct resource *res, const __be32 *from) +{ + return NULL; +} #endif /* CONFIG_OF_ADDRESS */