From patchwork Thu Apr 11 23:56:22 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Saravana Kannan X-Patchwork-Id: 13626652 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2AEF3C4345F for ; Thu, 11 Apr 2024 23:56:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Cc:To:From:Subject:References: Mime-Version:Message-Id:In-Reply-To:Date:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=/KvHj1m6DaIPQ6Y30td58eVuhZanoi+AtJYJUDelWYw=; b=GSjMvwkR7xZPRY+//75G0VZ3tt 0EHGWaGLe8gOuWai0dWXcMm8IYlpDPF1uPGxrDMB39vPbNo5BthSb0H+uZxZeeMgDoFMl9TWzJgLf xYdzF9brqM896iijErHUGoow4EpadmB4IkAFSBN30N4e9TX+gHnJACD4rO8Qs/unnPAyJ8mWdGjQv YXh+x7klkOVrsCmUMMZLTUvvHWDq081JjWPjKSYucVge18TQ3tKB+3b7WiKT1kJLBtcaPUmHKNy+o yF8aojwoHLy2RggJ21M6CkqbcY6VEOnzdpcoTXNKfHjCiaH8sfpp7RUMpkN8rodUxg+Hn+P2QGoVd 095BJ33Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rv4HZ-0000000EYUC-3T3K; Thu, 11 Apr 2024 23:56:41 +0000 Received: from mail-pj1-x104a.google.com ([2607:f8b0:4864:20::104a]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rv4HS-0000000EYRM-3ltj for linux-arm-kernel@lists.infradead.org; Thu, 11 Apr 2024 23:56:36 +0000 Received: by mail-pj1-x104a.google.com with SMTP id 98e67ed59e1d1-2a2e6197371so310323a91.3 for ; Thu, 11 Apr 2024 16:56:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1712879794; x=1713484594; darn=lists.infradead.org; h=cc:to:from:subject:references:mime-version:message-id:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=HizrqH7rz47v2QLp5elrgTIyG7EQRo9SAEpqH/+kBy0=; b=xvRifzmOJ0hJPQTfeWBo4Aq5HyWUx1v8Xm8FhBNQ8QAK90iu5iVPf90JvaSJM6QYGt r3gNaihSwoOERk7x6K9XA9ygjNL8XioPNFiF1yMQeTOu5ZVrfqAACM32gzZzK8RyNqGP CngabxdKEJ0T65A7y8tCQRQiWpKKRT8nKpH7YaxTxkZvC/yeOQ+fp6S7aTJZEqhG1hp2 oCu2OA6g+S2H4tne9tNtcgbzvA+lWrTJYbetiD3FbKo735ERQcmACJ7kzzTn0PEurFoG ZGkiia6T9jCUYu7gzGN+dFkMGg+AYY9wS0glmVL7Cj15ly91crk77tz73wMeW5WerNWm o8Yg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1712879794; x=1713484594; h=cc:to:from:subject:references:mime-version:message-id:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=HizrqH7rz47v2QLp5elrgTIyG7EQRo9SAEpqH/+kBy0=; b=FC0nl46DEE62scmTZFS111V3qzD6CdSiB441Bu+N3n1Ae5yac0phKe/mIeapCwkD35 mE//gHdPbqSwlGScrZRDZNA2uHlwdLjFYl1NlONJI93zjopGKFir1JHnxjntlP0jwfhz ExA1MN9HjQUY+tJKNe41UceMVTZQmZvWTxaIBKFrO85IYf05vXYZa7GNg7w6Dn9sdd1Y 0/f2cjVMdvGiQBsLb/WW/K6Zq/VojHJe3l9qzPlPt0qFYCOGt4Omf3sJGrSjqE6mtiKg T5F8wXDCeZT9oQ/JfmQ/2R33YL27Hhu7jbuJg2to5ddvZ0RWWHss5+/YTTQBoVDV79jy 9Uug== X-Forwarded-Encrypted: i=1; AJvYcCVjhmJMJuPZ4ODTRMDeglUezZAU9PVvx4LA5ax5n9qErR3JwDxRKNjzIFfUmzOERJ4Q95q/cCbW514C6A9lQl0MruGRwltySjuwPYOmtghZRXbFtsA= X-Gm-Message-State: AOJu0YzLs0O+EQo7cirBZz2EMcyQydf+1LbYNyGbHgTFTn/8nVd8XTut r82ZptWB/bxYgpVqy3hov7+ArjVWI0QqlD7zVNkgZNkkxKnttSRIIDzTov9buRVrgpMS9I2fT2F nAwUisP+WpX28Vg== X-Google-Smtp-Source: AGHT+IHqTq2UPkwQrTsIwISL3TPeqKf9uyBTI5tIlaviAP1Wf5pw15DCSNWSteziJ1gjlX/gPxjg3k35MoA1MA0= X-Received: from saravanak.san.corp.google.com ([2620:15c:2d:3:a472:f40c:d4ba:c29]) (user=saravanak job=sendgmr) by 2002:a17:90a:6546:b0:2a5:fb3a:32e6 with SMTP id f6-20020a17090a654600b002a5fb3a32e6mr3270pjs.4.1712879793807; Thu, 11 Apr 2024 16:56:33 -0700 (PDT) Date: Thu, 11 Apr 2024 16:56:22 -0700 In-Reply-To: <20240411235623.1260061-1-saravanak@google.com> Message-Id: <20240411235623.1260061-3-saravanak@google.com> Mime-Version: 1.0 References: <20240411235623.1260061-1-saravanak@google.com> X-Mailer: git-send-email 2.44.0.683.g7961c838ac-goog Subject: [PATCH v3 2/2] of: dynamic: Fix overlayed devices not probing because of fw_devlink From: Saravana Kannan To: Herve Codina , Greg Kroah-Hartman , "Rafael J. Wysocki" , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , Wolfram Sang , Rob Herring , Saravana Kannan , Mark Brown , Len Brown , Andy Shevchenko , Daniel Scally , Heikki Krogerus , Sakari Ailus , Geert Uytterhoeven Cc: kernel-team@android.com, Wolfram Sang , linux-kernel@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-i2c@vger.kernel.org, devicetree@vger.kernel.org, linux-spi@vger.kernel.org, linux-acpi@vger.kernel.org X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240411_165635_027095_7BEF1EE8 X-CRM114-Status: GOOD ( 24.86 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org When an overlay is applied, if the target device has already probed successfully and bound to a device, then some of the fw_devlink logic that ran when the device was probed needs to be rerun. This allows newly created dangling consumers of the overlayed device tree nodes to be moved to become consumers of the target device. Fixes: 1a50d9403fb9 ("treewide: Fix probing of devices in DT overlays") Reported-by: Herve Codina Closes: https://lore.kernel.org/lkml/CAMuHMdXEnSD4rRJ-o90x4OprUacN_rJgyo8x6=9F9rZ+-KzjOg@mail.gmail.com/ Closes: https://lore.kernel.org/all/20240221095137.616d2aaa@bootlin.com/ Closes: https://lore.kernel.org/lkml/20240312151835.29ef62a0@bootlin.com/ Signed-off-by: Saravana Kannan --- drivers/base/core.c | 76 +++++++++++++++++++++++++++++++++++++----- drivers/of/overlay.c | 15 +++++++++ include/linux/fwnode.h | 1 + 3 files changed, 83 insertions(+), 9 deletions(-) diff --git a/drivers/base/core.c b/drivers/base/core.c index 5f4e03336e68..1a646f393dd7 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -46,6 +46,8 @@ static bool fw_devlink_drv_reg_done; static bool fw_devlink_best_effort; static struct workqueue_struct *device_link_wq; +#define get_dev_from_fwnode(fwnode) get_device((fwnode)->dev) + /** * __fwnode_link_add - Create a link between two fwnode_handles. * @con: Consumer end of the link. @@ -237,6 +239,70 @@ static void __fw_devlink_pickup_dangling_consumers(struct fwnode_handle *fwnode, __fw_devlink_pickup_dangling_consumers(child, new_sup); } +static void fw_devlink_pickup_dangling_consumers(struct device *dev) +{ + struct fwnode_handle *child; + + mutex_lock(&fwnode_link_lock); + fwnode_for_each_available_child_node(dev->fwnode, child) + __fw_devlink_pickup_dangling_consumers(child, dev->fwnode); + __fw_devlink_link_to_consumers(dev); + mutex_unlock(&fwnode_link_lock); +} + +/** + * fw_devlink_refresh_fwnode - Recheck the tree under this firmware node + * @fwnode: The fwnode under which the fwnode tree has changed + * + * This function is mainly meant to adjust the supplier/consumer dependencies + * after a fwnode tree overlay has occurred. + */ +void fw_devlink_refresh_fwnode(struct fwnode_handle *fwnode) +{ + struct device *dev; + + /* + * Find the closest ancestor fwnode that has been converted to a device + * that can bind to a driver (bus device). + */ + fwnode_handle_get(fwnode); + do { + if (fwnode->flags & FWNODE_FLAG_NOT_DEVICE) + continue; + + dev = get_dev_from_fwnode(fwnode); + if (!dev) + continue; + + if (dev->bus) + break; + + put_device(dev); + } while ((fwnode = fwnode_get_next_parent(fwnode))); + + /* + * If none of the ancestor fwnodes have (yet) been converted to a device + * that can bind to a driver, there's nothing to fix up. + */ + if (!fwnode) + return; + + WARN(device_is_bound(dev) && dev->links.status != DL_DEV_DRIVER_BOUND, + "Don't multithread overlaying and probing the same device!\n"); + + /* + * If the device has already bound to a driver, then we need to redo + * some of the work that was done after the device was bound to a + * driver. If the device hasn't bound to a driver, running thing too + * soon would incorrectly pick up consumers that it shouldn't. + */ + if (dev->links.status == DL_DEV_DRIVER_BOUND) + fw_devlink_pickup_dangling_consumers(dev); + + put_device(dev); + fwnode_handle_put(fwnode); +} + static DEFINE_MUTEX(device_links_lock); DEFINE_STATIC_SRCU(device_links_srcu); @@ -1322,14 +1388,8 @@ void device_links_driver_bound(struct device *dev) * child firmware node. */ if (dev->fwnode && dev->fwnode->dev == dev) { - struct fwnode_handle *child; fwnode_links_purge_suppliers(dev->fwnode); - mutex_lock(&fwnode_link_lock); - fwnode_for_each_available_child_node(dev->fwnode, child) - __fw_devlink_pickup_dangling_consumers(child, - dev->fwnode); - __fw_devlink_link_to_consumers(dev); - mutex_unlock(&fwnode_link_lock); + fw_devlink_pickup_dangling_consumers(dev); } device_remove_file(dev, &dev_attr_waiting_for_supplier); @@ -1888,8 +1948,6 @@ static void fw_devlink_unblock_consumers(struct device *dev) device_links_write_unlock(); } -#define get_dev_from_fwnode(fwnode) get_device((fwnode)->dev) - static bool fwnode_init_without_drv(struct fwnode_handle *fwnode) { struct device *dev; diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c index 2ae7e9d24a64..7b2396c53127 100644 --- a/drivers/of/overlay.c +++ b/drivers/of/overlay.c @@ -179,6 +179,15 @@ static int overlay_notify(struct overlay_changeset *ovcs, return 0; } +static void overlay_fw_devlink_refresh(struct overlay_changeset *ovcs) +{ + for (int i = 0; i < ovcs->count; i++) { + struct device_node *np = ovcs->fragments[i].target; + + fw_devlink_refresh_fwnode(of_fwnode_handle(np)); + } +} + /* * The values of properties in the "/__symbols__" node are paths in * the ovcs->overlay_root. When duplicating the properties, the paths @@ -953,6 +962,12 @@ static int of_overlay_apply(struct overlay_changeset *ovcs, pr_err("overlay apply changeset entry notify error %d\n", ret); /* notify failure is not fatal, continue */ + /* + * Needs to happen after changset notify to give the listeners a chance + * to finish creating all the devices they need to create. + */ + overlay_fw_devlink_refresh(ovcs); + ret_tmp = overlay_notify(ovcs, OF_OVERLAY_POST_APPLY); if (ret_tmp) if (!ret) diff --git a/include/linux/fwnode.h b/include/linux/fwnode.h index 0d79070c5a70..95a78b87777a 100644 --- a/include/linux/fwnode.h +++ b/include/linux/fwnode.h @@ -220,6 +220,7 @@ int fwnode_link_add(struct fwnode_handle *con, struct fwnode_handle *sup, u8 flags); void fwnode_links_purge(struct fwnode_handle *fwnode); void fw_devlink_purge_absent_suppliers(struct fwnode_handle *fwnode); +void fw_devlink_refresh_fwnode(struct fwnode_handle *fwnode); bool fw_devlink_is_strict(void); #endif