From patchwork Thu Mar 30 12:08:02 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Wu, Hao" X-Patchwork-Id: 9654023 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 84E486034C for ; Thu, 30 Mar 2017 12:15:41 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7429F2858C for ; Thu, 30 Mar 2017 12:15:41 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 68DEC28591; Thu, 30 Mar 2017 12:15:41 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F1CD02858D for ; Thu, 30 Mar 2017 12:15:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933637AbdC3MPd (ORCPT ); Thu, 30 Mar 2017 08:15:33 -0400 Received: from mga02.intel.com ([134.134.136.20]:27696 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933466AbdC3MPb (ORCPT ); Thu, 30 Mar 2017 08:15:31 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=intel.com; i=@intel.com; q=dns/txt; s=intel; t=1490876130; x=1522412130; h=from:to:cc:subject:date:message-id:in-reply-to: references; bh=QUZrOZ/pkw4fWL2z2VExmK360sZ+Ynh1DzApDpLWyAc=; b=sqgn5XSYj+6Gfuw8VIg0WLzbm2RFWY+ctc1q0SPrn14aVwsdBQBgMep0 wbpuJKiXXU5uke/HwCsmaaghmXT2Hg==; Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 30 Mar 2017 05:15:30 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.36,246,1486454400"; d="scan'208";a="840018069" Received: from hao-dev.bj.intel.com ([10.238.157.61]) by FMSMGA003.fm.intel.com with ESMTP; 30 Mar 2017 05:15:27 -0700 From: Wu Hao To: atull@kernel.org, moritz.fischer@ettus.com, linux-fpga@vger.kernel.org, linux-kernel@vger.kernel.org Cc: luwei.kang@intel.com, yi.z.zhang@intel.com, hao.wu@intel.com, Tim Whisonant , Enno Luebbers , Shiva Rao , Christopher Rauer , Xiao Guangrong Subject: [PATCH 02/16] fpga: add FPGA device framework Date: Thu, 30 Mar 2017 20:08:02 +0800 Message-Id: <1490875696-15145-3-git-send-email-hao.wu@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1490875696-15145-1-git-send-email-hao.wu@intel.com> References: <1490875696-15145-1-git-send-email-hao.wu@intel.com> Sender: linux-fpga-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fpga@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP During FPGA device (e.g PCI-based) discovery, platform devices are registered for different FPGA function units. But the device node path isn't quite friendly to applications. Consider this case, applications want to access child device's sysfs file for some information. 1) Access using bus-based path (e.g PCI) /sys/bus/pci/devices/xxxxx/fpga_func_a.0/sysfs_file From the path, it's clear which PCI device is the parent, but not perfect solution for applications. PCI device BDF is not fixed, application may need to search all PCI device to find the actual FPGA Device. 2) Or access using platform device path /sys/bus/platform/devices/fpga_func_a.0/sysfs_file Applications find the actual function by name easily, but no information about which fpga device it belongs to. It's quite confusing if multiple FPGA devices are in one system. 'FPGA Device' class is introduced to resolve this problem. Each node under this class represents a fpga device, which may have one or more child devices. Applications only need to search under this FPGA Device class folder to find the child device node it needs. For example, for the platform has 2 fpga devices, each fpga device has 3 child devices, the hierarchy looks like this. Two nodes are under /sys/class/fpga/: /sys/class/fpga/fpga.0 /sys/class/fpga/fpga.1 Each node has 1 function A device and 2 function B devices: /sys/class/fpga/fpga.0/func_a.0 /sys/class/fpga/fpga.0/func_b.0 /sys/class/fpga/fpga.0/func_b.1 /sys/class/fpga/fpga.1/func_a.1 /sys/class/fpga/fpga.1/func_b.2 /sys/class/fpga/fpga.1/func_b.3 This following APIs are provided by FPGA device framework: * fpga_dev_create Create fpga device under the given parent device. * fpga_dev_destroy Destroy fpga device The following sysfs files are created: * /sys/class/fpga//name Name of the fpga device. Signed-off-by: Tim Whisonant Signed-off-by: Enno Luebbers Signed-off-by: Shiva Rao Signed-off-by: Christopher Rauer Signed-off-by: Xiao Guangrong Signed-off-by: Wu Hao --- drivers/fpga/Kconfig | 6 +++ drivers/fpga/Makefile | 3 ++ drivers/fpga/fpga-dev.c | 120 ++++++++++++++++++++++++++++++++++++++++++ include/linux/fpga/fpga-dev.h | 34 ++++++++++++ 4 files changed, 163 insertions(+) create mode 100644 drivers/fpga/fpga-dev.c create mode 100644 include/linux/fpga/fpga-dev.h diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig index ce861a2..d99b640 100644 --- a/drivers/fpga/Kconfig +++ b/drivers/fpga/Kconfig @@ -12,6 +12,12 @@ config FPGA manager drivers. if FPGA +config FPGA_DEVICE + tristate "FPGA Device Framework" + help + Say Y here if you want support for FPGA Devices from the kernel. + The FPGA Device Framework adds a FPGA device class and provide + interfaces to create FPGA devices. config FPGA_REGION tristate "FPGA Region" diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile index 8df07bc..53a41d2 100644 --- a/drivers/fpga/Makefile +++ b/drivers/fpga/Makefile @@ -5,6 +5,9 @@ # Core FPGA Manager Framework obj-$(CONFIG_FPGA) += fpga-mgr.o +# FPGA Device Framework +obj-$(CONFIG_FPGA_DEVICE) += fpga-dev.o + # FPGA Manager Drivers obj-$(CONFIG_FPGA_MGR_SOCFPGA) += socfpga.o obj-$(CONFIG_FPGA_MGR_SOCFPGA_A10) += socfpga-a10.o diff --git a/drivers/fpga/fpga-dev.c b/drivers/fpga/fpga-dev.c new file mode 100644 index 0000000..0f4c0ed --- /dev/null +++ b/drivers/fpga/fpga-dev.c @@ -0,0 +1,120 @@ +/* + * FPGA Device Framework Driver + * + * Copyright (C) 2017 Intel Corporation, Inc. + * + * This work is licensed under a dual BSD/GPLv2 license. When using or + * redistributing this file, you may do so under either license. See the + * LICENSE.BSD file under drivers/fpga/intel for the BSD license and see + * the COPYING file in the top-level directory for the GPLv2 license. + */ +#include +#include +#include +#include + +static DEFINE_IDA(fpga_dev_ida); +static struct class *fpga_dev_class; + +static ssize_t name_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct fpga_dev *fdev = to_fpga_dev(dev); + + return sprintf(buf, "%s\n", fdev->name); +} +static DEVICE_ATTR_RO(name); + +static struct attribute *fpga_dev_attrs[] = { + &dev_attr_name.attr, + NULL, +}; +ATTRIBUTE_GROUPS(fpga_dev); + +/** + * fpga_dev_create - create a fpga device + * @parent: parent device + * @name: fpga device name + * + * Return fpga_dev struct for success, error code otherwise. + */ +struct fpga_dev *fpga_dev_create(struct device *parent, const char *name) +{ + struct fpga_dev *fdev; + int id, ret = 0; + + if (!name || !strlen(name)) { + dev_err(parent, "Attempt to register with no name!\n"); + return ERR_PTR(-EINVAL); + } + + fdev = kzalloc(sizeof(*fdev), GFP_KERNEL); + if (!fdev) + return ERR_PTR(-ENOMEM); + + id = ida_simple_get(&fpga_dev_ida, 0, 0, GFP_KERNEL); + if (id < 0) { + ret = id; + goto error_kfree; + } + + fdev->name = name; + + device_initialize(&fdev->dev); + fdev->dev.class = fpga_dev_class; + fdev->dev.parent = parent; + fdev->dev.id = id; + + ret = dev_set_name(&fdev->dev, "fpga.%d", id); + if (ret) + goto error_device; + + ret = device_add(&fdev->dev); + if (ret) + goto error_device; + + dev_dbg(fdev->dev.parent, "fpga device [%s] created\n", fdev->name); + + return fdev; + +error_device: + ida_simple_remove(&fpga_dev_ida, id); +error_kfree: + kfree(fdev); + + return ERR_PTR(ret); +} +EXPORT_SYMBOL_GPL(fpga_dev_create); + +static void fpga_dev_release(struct device *dev) +{ + struct fpga_dev *fdev = to_fpga_dev(dev); + + ida_simple_remove(&fpga_dev_ida, fdev->dev.id); + kfree(fdev); +} + +static int __init fpga_dev_class_init(void) +{ + pr_info("FPGA Device framework\n"); + + fpga_dev_class = class_create(THIS_MODULE, "fpga"); + if (IS_ERR(fpga_dev_class)) + return PTR_ERR(fpga_dev_class); + + fpga_dev_class->dev_groups = fpga_dev_groups; + fpga_dev_class->dev_release = fpga_dev_release; + + return 0; +} + +static void __exit fpga_dev_class_exit(void) +{ + class_destroy(fpga_dev_class); +} + +MODULE_DESCRIPTION("FPGA Device framework"); +MODULE_LICENSE("Dual BSD/GPL"); + +subsys_initcall(fpga_dev_class_init); +module_exit(fpga_dev_class_exit); diff --git a/include/linux/fpga/fpga-dev.h b/include/linux/fpga/fpga-dev.h new file mode 100644 index 0000000..7b58356 --- /dev/null +++ b/include/linux/fpga/fpga-dev.h @@ -0,0 +1,34 @@ +/* + * FPGA Device Driver Header + * + * Copyright (C) 2017 Intel Corporation, Inc. + * + * This work is licensed under a dual BSD/GPLv2 license. When using or + * redistributing this file, you may do so under either license. See the + * LICENSE.BSD file under drivers/fpga/intel for the BSD license and see + * the COPYING file in the top-level directory for the GPLv2 license. + * + */ +#ifndef _LINUX_FPGA_DEV_H +#define _LINUX_FPGA_DEV_H + +/** + * struct fpga_dev - fpga device structure + * @name: name of fpga device + * @dev: fpga device + */ +struct fpga_dev { + const char *name; + struct device dev; +}; + +#define to_fpga_dev(d) container_of(d, struct fpga_dev, dev) + +struct fpga_dev *fpga_dev_create(struct device *parent, const char *name); + +static inline void fpga_dev_destroy(struct fpga_dev *fdev) +{ + device_unregister(&fdev->dev); +} + +#endif