From patchwork Mon Jan 18 15:16:38 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Auger X-Patchwork-Id: 569561 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id F159C1402CD for ; Tue, 19 Jan 2016 02:17:35 +1100 (AEDT) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=linaro.org header.i=@linaro.org header.b=fcX+JVUU; dkim-atps=neutral Received: from localhost ([::1]:60250 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aLBYj-0000b2-P8 for incoming@patchwork.ozlabs.org; Mon, 18 Jan 2016 10:17:33 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48580) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aLBY8-0007tZ-L6 for qemu-devel@nongnu.org; Mon, 18 Jan 2016 10:16:58 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aLBY7-0001an-BE for qemu-devel@nongnu.org; Mon, 18 Jan 2016 10:16:56 -0500 Received: from mail-wm0-x233.google.com ([2a00:1450:400c:c09::233]:33953) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aLBY7-0001aP-1a for qemu-devel@nongnu.org; Mon, 18 Jan 2016 10:16:55 -0500 Received: by mail-wm0-x233.google.com with SMTP id u188so108051012wmu.1 for ; Mon, 18 Jan 2016 07:16:54 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=Fyo/zUr7Z8b70EQnLIZRqeVkx1MHZR78WEB5QlMVEGk=; b=fcX+JVUUlo6AAibSc3canm/r+Cpcf0+lgMFSYr8vq4wRThI7tr4M/6lEP3EP2PVkkA Q9sjUcJ3jHg2WxgCXxrmY7A4rUur3OUWZ7y14a1JYvRbdVixaBbg8pMw8BJbMGJFxOXF PhUfjQ2Pvqpbfpa1uZeztQHXqcSuhNIYYMsNM= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=Fyo/zUr7Z8b70EQnLIZRqeVkx1MHZR78WEB5QlMVEGk=; b=i7CvbaQ5yZ2qkoaw7T03C0I5HJ/LupxyEnl/ateM4OLtD6fX7k8yoVQplvgCxBGV8Z cwtspp+ix1kmfSDXCHmX1OiSW+CbV9O/vVPBaoyI9O/kjGEs3ImjsE4KYSMs4UVxIlTg 5n7Ptm/fDZeiH1IK2pPFMM4EcGjZJkv4i8XiG+qMt0O5eqyxYYoSoTqwOyiZukgKwFDM 3DyK+GM+0hNUap9oU/3J/9jfJfxp2PSD5ToJ3VCK1uMPNuz6kFuc+WCvc5XqeSmIzgTx Qr0pP5E5fzYbZw8uQvTC9LGb137T6657HuoZmu09f31S84c265v0kguTSoWEvbPE8EpL Ubnw== X-Gm-Message-State: AG10YOSxfcYISmXrrqFn/eBovM+nlt6LCkyjicL16qGzN3j4rWwHPXh+cU92HhDzTTWVkKh3 X-Received: by 10.28.11.73 with SMTP id 70mr13498007wml.40.1453130214462; Mon, 18 Jan 2016 07:16:54 -0800 (PST) Received: from new-host-9.home (LMontsouris-657-1-37-90.w80-11.abo.wanadoo.fr. [80.11.198.90]) by smtp.gmail.com with ESMTPSA id o7sm24230067wjf.45.2016.01.18.07.16.52 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 18 Jan 2016 07:16:52 -0800 (PST) From: Eric Auger To: eric.auger@st.com, eric.auger@linaro.org, qemu-devel@nongnu.org, qemu-arm@nongnu.org, peter.maydell@linaro.org, david@gibson.dropbear.id.au, alex.williamson@redhat.com Date: Mon, 18 Jan 2016 15:16:38 +0000 Message-Id: <1453130204-655-3-git-send-email-eric.auger@linaro.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1453130204-655-1-git-send-email-eric.auger@linaro.org> References: <1453130204-655-1-git-send-email-eric.auger@linaro.org> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2a00:1450:400c:c09::233 Cc: thomas.lendacky@amd.com, thuth@redhat.com, b.reynal@virtualopensystems.com, patches@linaro.org, crosthwaitepeter@gmail.com, suravee.suthikulpanit@amd.com, pbonzini@redhat.com, alex.bennee@linaro.org, christoffer.dall@linaro.org Subject: [Qemu-devel] [PATCH v5 2/8] device_tree: introduce load_device_tree_from_sysfs X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org This function returns the host device tree blob from sysfs (/proc/device-tree). It uses a recursive function inspired from dtc read_fstree. Signed-off-by: Eric Auger --- v1 -> v2: - do not implement/expose read_fstree and load_device_tree_from_sysfs if CONFIG_LINUX is not defined (lstat is not implemeted in mingw) - correct indentation in read_fstree - use /proc/device-tree symlink instead of /sys/firmware/devicetree/base path (kernel.org/doc/Documentation/ABI/testing/sysfs-firmware-ofw) - use g_file_get_contents in read_fstree - introduce SYSFS_DT_BASEDIR macro and use strlen - exit on error in load_device_tree_from_sysfs - user error_setg RFC -> v1: - remove runtime dependency on dtc binary and introduce read_fstree --- device_tree.c | 100 +++++++++++++++++++++++++++++++++++++++++++ include/sysemu/device_tree.h | 3 ++ 2 files changed, 103 insertions(+) diff --git a/device_tree.c b/device_tree.c index a9f5f8e..b262c2d 100644 --- a/device_tree.c +++ b/device_tree.c @@ -17,6 +17,9 @@ #include #include #include +#ifdef CONFIG_LINUX +#include +#endif #include "qemu-common.h" #include "qemu/error-report.h" @@ -117,6 +120,103 @@ fail: return NULL; } +#ifdef CONFIG_LINUX + +#define SYSFS_DT_BASEDIR "/proc/device-tree" + +/** + * read_fstree: this function is inspired from dtc read_fstree + * @fdt: preallocated fdt blob buffer, to be populated + * @dirname: directory to scan under SYSFS_DT_BASEDIR + * the search is recursive and the tree is searched down to the + * leafs (property files). + * + * the function self-asserts in case of error + */ +static void read_fstree(void *fdt, const char *dirname) +{ + DIR *d; + struct dirent *de; + struct stat st; + const char *root_dir = SYSFS_DT_BASEDIR; + char *parent_node; + + if (strstr(dirname, root_dir) != dirname) { + error_report("%s: %s must be searched within %s", + __func__, dirname, root_dir); + exit(1); + } + parent_node = (char *)&dirname[strlen(SYSFS_DT_BASEDIR)]; + + d = opendir(dirname); + if (!d) { + error_setg(&error_fatal, "%s cannot open %s", __func__, dirname); + } + + while ((de = readdir(d)) != NULL) { + char *tmpnam; + + if (!g_strcmp0(de->d_name, ".") + || !g_strcmp0(de->d_name, "..")) { + continue; + } + + tmpnam = g_strjoin("/", dirname, de->d_name, NULL); + + if (lstat(tmpnam, &st) < 0) { + error_setg(&error_fatal, "%s cannot lstat %s", __func__, tmpnam); + } + + if (S_ISREG(st.st_mode)) { + gchar *val; + gsize len; + + if (!g_file_get_contents(tmpnam, &val, &len, NULL)) { + error_setg(&error_fatal, "%s not able to extract info from %s", + __func__, tmpnam); + } + + if (strlen(parent_node) > 0) { + qemu_fdt_setprop(fdt, parent_node, + de->d_name, val, len); + } else { + qemu_fdt_setprop(fdt, "/", de->d_name, val, len); + } + g_free(val); + } else if (S_ISDIR(st.st_mode)) { + char *node_name; + + node_name = g_strdup_printf("%s/%s", + parent_node, de->d_name); + qemu_fdt_add_subnode(fdt, node_name); + g_free(node_name); + read_fstree(fdt, tmpnam); + } + + g_free(tmpnam); + } + + closedir(d); +} + +/* load_device_tree_from_sysfs: extract the dt blob from host sysfs */ +void *load_device_tree_from_sysfs(void) +{ + void *host_fdt; + int host_fdt_size; + + host_fdt = create_device_tree(&host_fdt_size); + read_fstree(host_fdt, SYSFS_DT_BASEDIR); + if (fdt_check_header(host_fdt)) { + error_setg(&error_fatal, + "%s host device tree extracted into memory is invalid", + __func__); + } + return host_fdt; +} + +#endif /* CONFIG_LINUX */ + static int findnode_nofail(void *fdt, const char *node_path) { int offset; diff --git a/include/sysemu/device_tree.h b/include/sysemu/device_tree.h index 359e143..fdf25a4 100644 --- a/include/sysemu/device_tree.h +++ b/include/sysemu/device_tree.h @@ -16,6 +16,9 @@ void *create_device_tree(int *sizep); void *load_device_tree(const char *filename_path, int *sizep); +#ifdef CONFIG_LINUX +void *load_device_tree_from_sysfs(void); +#endif int qemu_fdt_setprop(void *fdt, const char *node_path, const char *property, const void *val, int size);