From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f43.google.com (mail-wm1-f43.google.com [209.85.128.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D154D39D6FA for ; Thu, 30 Jul 2026 10:25:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.43 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785407110; cv=none; b=NVrP2KgFsSWw/6oq4bicJXoD8fE0nWAcvFfofQOAI6hKp4+JT+RgTHWbJCTRZ+w9Ew7nE/c59+sVJhecaUkmTbiRA82jMfkOObOQhLHzaEUUEsW/9VMT+bfn+/FkF3rzdufl1bDyQj+Cz5uZ8MdqMoVyP8OF8GQojywl4O+NypI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785407110; c=relaxed/simple; bh=xBRx4nU+Q+o/8/p+KCuQFmd/7/h0WdyvKVWwmf/wBh4=; h=From:To:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=S0dOA3w4Vw/yC88ByI/k3hhMJQEae7M4Yqj7Pj8ks7Ar9yFGHO4sYLW7Fbd+3lF16gu6c4pm7VUegegRG4xKeglFif1t/Cd50D948LrnNrOdxdzMkIPgSDrGb/QPk170/OMVeUULbfnaqBDbjoK8jd/4KkeH8rM6QFR3roVOGcM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=LFGW5ZFl; arc=none smtp.client-ip=209.85.128.43 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="LFGW5ZFl" Received: by mail-wm1-f43.google.com with SMTP id 5b1f17b1804b1-495757ccbc1so17344795e9.2 for ; Thu, 30 Jul 2026 03:25:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1785407106; x=1786011906; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:from:to:cc:subject:date:message-id :reply-to:content-type; bh=5M6b8h2Qx7uz2S7lrJX2+QvSSsq1tSsAAn6JVK5UB6A=; b=LFGW5ZFlZFcCKBYIDXEf3sL/xlQ7M2WrwUfbXVhV8NVozVerX2SYn6YvLV033SDicj u6ofP/CTXxoq47BqIQZ6huSvsT7wLO4b7hps+0k4Xg5/h2aLsc7ergxm8TS6vmDGQCKn ypPFe8gd4wivmkS77pUVg4Xb0xzrMYOb/Pzt9l6zM1wguO51IzEdc0pGBdartKUmP77L 6PV2kkIGY3zAwUt/d+PjWWIS+zltnS/SPmwVzagFd9chJpFE/u9qMfqT9BZ4xzhImUEy kY7iyJVgmaxn/luDLYqX4fVN4Vne9UJzT5IFEwN+xr+iKHJ8OOwIuIDwd+KO7OhzP48Z fDZg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1785407106; x=1786011906; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:x-gm-gg:x-gm-message-state:from:to :cc:subject:date:message-id:reply-to:content-type; bh=5M6b8h2Qx7uz2S7lrJX2+QvSSsq1tSsAAn6JVK5UB6A=; b=Mtj33pws9v25p4xEgpbRBj50cnJvk31Ef4hUis7/gKhKNZVb1YXxN1iHypoXXUICXB wGROcSRpA3nqD6rnC8/tz1PY7crvMs2CL6dtTWeRtTq96jt42/sQA9fIS/8KUrgYb2pd F2lqiiWmPG9vvFapm3X9hjJ2ExFQ3zov6F4rHdmWiafTyjKv/tBbQhcfgGAGw3swl34T EcI0CCBpsqZZKQ5BULS9440rJG2W+Pjq9k/3VDsqM0sWKtEUeG0+gAjllxHkFLVSi8H+ uOyaRAamsqaUQXpoiJy+DBL3kJgM8DGdTgtOAHMIxg7bZEpcoArqdym9LFWlR3rUFD4i t+rA== X-Forwarded-Encrypted: i=1; AHgh+Rq9hjJCepMvLpbKdH8K7ZfjB1LupQzhKo1kGOsSaTGgJTstVsfm+q7GM4SAk5g61aHICNepq7d+1GM=@vger.kernel.org X-Gm-Message-State: AOJu0Yxg3uEI90Oia7mjf6WokmCLHJLiRkCjt49KEKq6qmyMQPw8QSYp Mv9TUW8qqPOfixh3AxMUDgy5BXnFdo7UkK7d7aXhyZ/ns5Vf9wGqv3Gg X-Gm-Gg: AR+sD133i4v0vj91WSBfFm2mfd+U7KcB3J/xhpb4KxVF9+IhI9WrAA0/4B7qqOnuiYZ w2DWSdQOetGjTC7F/23Pe89v3LusdT5ruLMPd5a1cXOM30TmyrWN/rkTFjSuflsyLwppTZncG98 jz4XX9D+yEGeuPNalrVmpo8oynwvQf0cC+f/Ry724j7WXzzrajrgjs4+nSuLOxGJ+bUyg4Xsd4x dvtw5MltQWhcDdbjGd5nmIhcaLCLXtOQ7KlNrJ6NrLxxCZ+156SjCLxocgkHxBYI2k2WCdTeFaW rlhUKdEhZBvgQ2YqdtF70M7lphaJb7GDT9S1qEyipmqMJlAs/QkUPzkoOmFUModyVEWrBv46M4/ kWyK0lezTqRUlVM3K7orOJkKJ3h36EDcbkG8iG8ASZI63bk4TwgOWBhodxkQUMamGdooqfJ3TMV yiExJW4Bkym+AISpaCD5o3LyCr9z0+hEfg9SiNz8HQJtOsZYrj1BtzYbfEH9OPoqb+XVi4Z2VM5 3q/Y/u6lzzhRVsT0ny5DSj2hp1uHu/mfsp84Afarzlw01a91ZVUDA== X-Received: by 2002:a05:600c:1d8c:b0:495:6713:9a40 with SMTP id 5b1f17b1804b1-49800ea2aecmr25646785e9.18.1785407105759; Thu, 30 Jul 2026 03:25:05 -0700 (PDT) Received: from Ansuel-XPS24.localdomain (host-87-11-254-126.retail.telecomitalia.it. [87.11.254.126]) by smtp.googlemail.com with ESMTPSA id 5b1f17b1804b1-498011fd5fesm44720295e9.7.2026.07.30.03.25.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 30 Jul 2026 03:25:05 -0700 (PDT) From: Christian Marangi To: Maxime Chevallier , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Simon Horman , Jonathan Corbet , Shuah Khan , Christian Marangi , Lorenzo Bianconi , Heiner Kallweit , Russell King , Philipp Zabel , Nathan Chancellor , Nick Desaulniers , Bill Wendling , Justin Stitt , netdev@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, llvm@lists.linux.dev Subject: [PATCH net-next v10 05/11] net: phylink: support late PCS provider attach Date: Thu, 30 Jul 2026 12:24:16 +0200 Message-ID: <20260730102444.1967900-6-ansuelsmth@gmail.com> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260730102444.1967900-1-ansuelsmth@gmail.com> References: <20260730102444.1967900-1-ansuelsmth@gmail.com> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Add support for late PCS provider attachment to a phylink instance. This works by creating a global notifier for the PCS provider and making each phylink instance that makes use of fwnode subscribe to this notifier. The PCS notifier will emit the event FWNODE_PCS_PROVIDER_ADD every time a new PCS provider is added. phylink will then react to this event and will call the new function fwnode_phylink_pcs_get_from_fwnode() that will check if the PCS fwnode provided by the event is present in the pcs-handle property of the phylink instance. If a related PCS is found, then such PCS is added to the phylink instance PCS list. Then we link the PCS to the phylink instance and we refresh the supported interfaces of the phylink instance. Finally we check if we are in a major_config_failed scenario and trigger an interface reconfiguration in the next phylink resolve. In the example scenario where the link was previously torn down due to removal of PCS, the link will be established again as the PCS came back and is now available to phylink. Signed-off-by: Christian Marangi --- drivers/net/pcs/pcs.c | 49 +++++++++++++++++++++ drivers/net/phy/phylink.c | 93 ++++++++++++++++++++++++++++++++++++--- include/linux/pcs/pcs.h | 65 +++++++++++++++++++++++++++ 3 files changed, 201 insertions(+), 6 deletions(-) diff --git a/drivers/net/pcs/pcs.c b/drivers/net/pcs/pcs.c index fa8ab67076e2..ec0409909955 100644 --- a/drivers/net/pcs/pcs.c +++ b/drivers/net/pcs/pcs.c @@ -22,6 +22,19 @@ struct fwnode_pcs_provider { static LIST_HEAD(fwnode_pcs_providers); static DEFINE_MUTEX(fwnode_pcs_mutex); +static BLOCKING_NOTIFIER_HEAD(fwnode_pcs_notify_list); + +int register_fwnode_pcs_notifier(struct notifier_block *nb) +{ + return blocking_notifier_chain_register(&fwnode_pcs_notify_list, nb); +} +EXPORT_SYMBOL_GPL(register_fwnode_pcs_notifier); + +int unregister_fwnode_pcs_notifier(struct notifier_block *nb) +{ + return blocking_notifier_chain_unregister(&fwnode_pcs_notify_list, nb); +} +EXPORT_SYMBOL_GPL(unregister_fwnode_pcs_notifier); struct phylink_pcs *fwnode_pcs_simple_get(struct fwnode_reference_args *pcsspec, void *data) @@ -55,6 +68,10 @@ int fwnode_pcs_add_provider(struct fwnode_handle *fwnode, fwnode_dev_initialized(fwnode, true); + blocking_notifier_call_chain(&fwnode_pcs_notify_list, + FWNODE_PCS_PROVIDER_ADD, + fwnode); + return 0; } EXPORT_SYMBOL_GPL(fwnode_pcs_add_provider); @@ -150,6 +167,38 @@ struct phylink_pcs *fwnode_pcs_get(struct fwnode_handle *fwnode, unsigned int in } EXPORT_SYMBOL_GPL(fwnode_pcs_get); +struct phylink_pcs * +fwnode_phylink_pcs_get_from_fwnode(struct fwnode_handle *fwnode, + struct fwnode_handle *pcs_fwnode) +{ + struct fwnode_reference_args pcsspec; + int index = 0; + int ret; + + /* Loop until we find a matching PCS node or + * fwnode_parse_pcsspec() returns error + * if we don't have any other PCS reference to check. + */ + while (true) { + ret = fwnode_parse_pcsspec(fwnode, index, NULL, &pcsspec); + if (ret) + return ERR_PTR(ret); + + /* Exit loop if we found the matching PCS node */ + if (pcsspec.fwnode == pcs_fwnode) { + fwnode_handle_put(pcsspec.fwnode); + break; + } + + /* Check the next PCS reference */ + fwnode_handle_put(pcsspec.fwnode); + index++; + } + + return fwnode_pcs_get(fwnode, index); +} +EXPORT_SYMBOL_GPL(fwnode_phylink_pcs_get_from_fwnode); + unsigned int fwnode_phylink_pcs_count(struct fwnode_handle *fwnode) { struct fwnode_reference_args out_args; diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c index 562e09d1838b..d38820543ae4 100644 --- a/drivers/net/phy/phylink.c +++ b/drivers/net/phy/phylink.c @@ -12,6 +12,7 @@ #include #include #include +#include #include #include #include @@ -62,6 +63,7 @@ struct phylink { /* List of available PCS */ struct list_head pcs_list; + struct notifier_block fwnode_pcs_nb; /* What interface are supported by the current link. * Can change on removal or addition of new PCS. @@ -1965,6 +1967,27 @@ int phylink_set_fixed_link(struct phylink *pl, } EXPORT_SYMBOL_GPL(phylink_set_fixed_link); +static void phylink_add_pcs(struct phylink *pl, struct phylink_pcs *pcs) +{ + struct phylink_pcs *tmp; + + /* + * Make sure state mutex is locked to protect concurrent + * access to phylink instance PCS list from + * initial fill_available_pcs and late PCS attach + */ + lockdep_assert_held(&pl->state_mutex); + + list_for_each_entry(tmp, &pl->pcs_list, list) + if (tmp == pcs) + return; + + list_add_tail(&pcs->list, &pl->pcs_list); + + /* Link PCS to phylink */ + pcs->phylink = pl; +} + static int phylink_fill_available_pcs(struct phylink *pl, struct phylink_config *config) { @@ -1988,21 +2011,70 @@ static int phylink_fill_available_pcs(struct phylink *pl, if (ret < 0) goto out; + mutex_lock(&pl->state_mutex); + for (i = 0; i < config->num_possible_pcs; i++) { struct phylink_pcs *pcs = pcss[i]; if (!pcs) continue; - list_add_tail(&pcs->list, &pl->pcs_list); + phylink_add_pcs(pl, pcs); } + mutex_unlock(&pl->state_mutex); + out: kfree(pcss); return ret; } +static int pcs_provider_notify(struct notifier_block *self, + unsigned long val, void *data) +{ + struct phylink *pl = container_of(self, struct phylink, fwnode_pcs_nb); + struct fwnode_handle *pcs_fwnode = data; + struct phylink_pcs *pcs; + + rtnl_lock(); + + /* Check if the just added PCS provider is + * in the phylink instance pcs-handle property. + */ + pcs = fwnode_phylink_pcs_get_from_fwnode(dev_fwnode(pl->config->dev), + pcs_fwnode); + if (IS_ERR(pcs)) { + rtnl_unlock(); + return NOTIFY_DONE; + } + + /* Add the PCS */ + mutex_lock(&pl->state_mutex); + + phylink_add_pcs(pl, pcs); + + /* Refresh supported interfaces */ + phy_interface_copy(pl->supported_interfaces, + pl->config->supported_interfaces); + list_for_each_entry(pcs, &pl->pcs_list, list) + phy_interface_or(pl->supported_interfaces, + pl->supported_interfaces, + pcs->supported_interfaces); + + /* Force an interface reconfig if major config fail */ + if (pl->major_config_failed) + pl->force_major_config = true; + + mutex_unlock(&pl->state_mutex); + + rtnl_unlock(); + + phylink_run_resolve(pl); + + return NOTIFY_OK; +} + /** * phylink_create() - create a phylink instance * @config: a pointer to the target &struct phylink_config @@ -2047,15 +2119,21 @@ struct phylink *phylink_create(struct phylink_config *config, INIT_WORK(&pl->resolve, phylink_resolve); INIT_LIST_HEAD(&pl->pcs_list); + /* + * First register notifier for late PCS attach to catch + * any possible provider that registers while we fill + * the available PCS. + */ + if (!phy_interface_empty(config->pcs_interfaces)) { + pl->fwnode_pcs_nb.notifier_call = pcs_provider_notify; + register_fwnode_pcs_notifier(&pl->fwnode_pcs_nb); + } + /* Fill the PCS list with available PCS from phylink config */ ret = phylink_fill_available_pcs(pl, config); if (ret < 0) goto free_pl; - /* Link available PCS to phylink */ - list_for_each_entry(pcs, &pl->pcs_list, list) - pcs->phylink = pl; - phy_interface_copy(pl->supported_interfaces, config->supported_interfaces); @@ -2151,10 +2229,13 @@ void phylink_destroy(struct phylink *pl) if (pl->link_gpio) gpiod_put(pl->link_gpio); + /* Unregister notifier for late PCS attach */ + if (pl->fwnode_pcs_nb.notifier_call) + unregister_fwnode_pcs_notifier(&pl->fwnode_pcs_nb); + cancel_work_sync(&pl->resolve); /* Drop link between PCS and phylink */ - /* Remove every PCS from phylink PCS list */ list_for_each_entry_safe(pcs, tmp, &pl->pcs_list, list) { pcs->phylink = NULL; list_del(&pcs->list); diff --git a/include/linux/pcs/pcs.h b/include/linux/pcs/pcs.h index b7cfdd680b2a..45e8f96662db 100644 --- a/include/linux/pcs/pcs.h +++ b/include/linux/pcs/pcs.h @@ -4,7 +4,36 @@ #include +enum fwnode_pcs_notify_event { + FWNODE_PCS_PROVIDER_ADD, +}; + #if IS_ENABLED(CONFIG_FWNODE_PCS) +/** + * register_fwnode_pcs_notifier - Register a notifier block for fwnode + * PCS events + * @nb: pointer to the notifier block + * + * Registers a notifier block to the fwnode_pcs_notify_list blocking + * notifier chain. This allows phylink instance to subscribe for + * PCS provider events. + * + * Returns: 0 or a negative error. + */ +int register_fwnode_pcs_notifier(struct notifier_block *nb); + +/** + * unregister_fwnode_pcs_notifier - Unregister a notifier block for fwnode + * PCS events + * @nb: pointer to the notifier block + * + * Unregisters a notifier block to the fwnode_pcs_notify_list blocking + * notifier chain. + * + * Returns: 0 or a negative error. + */ +int unregister_fwnode_pcs_notifier(struct notifier_block *nb); + /** * fwnode_pcs_get - Retrieves a PCS from a firmware node * @fwnode: firmware node @@ -20,6 +49,25 @@ struct phylink_pcs *fwnode_pcs_get(struct fwnode_handle *fwnode, unsigned int index); +/** + * fwnode_phylink_pcs_get_from_fwnode - Retrieves the PCS provided + * by the firmware node from a + * firmware node + * @fwnode: firmware node + * @pcs_fwnode: PCS firmware node + * + * Parse 'pcs-handle' in 'fwnode' and get the PCS that match + * 'pcs_fwnode' firmware node. + * + * Returns: a pointer to the phylink_pcs or a negative + * error pointer. Can return -EPROBE_DEFER if the PCS is not + * present in global providers list (either due to driver + * still needs to be probed or it failed to probe/removed) + */ +struct phylink_pcs * +fwnode_phylink_pcs_get_from_fwnode(struct fwnode_handle *fwnode, + struct fwnode_handle *pcs_fwnode); + /** * fwnode_phylink_pcs_count - count PCS entries described in firmware node * @fwnode: firmware node @@ -53,12 +101,29 @@ int fwnode_phylink_pcs_parse(struct fwnode_handle *fwnode, struct phylink_pcs **available_pcs, unsigned int num_pcs); #else +static inline int register_fwnode_pcs_notifier(struct notifier_block *nb) +{ + return -EOPNOTSUPP; +} + +static inline int unregister_fwnode_pcs_notifier(struct notifier_block *nb) +{ + return -EOPNOTSUPP; +} + static inline struct phylink_pcs *fwnode_pcs_get(struct fwnode_handle *fwnode, unsigned int index) { return ERR_PTR(-ENOENT); } +static inline struct phylink_pcs * +fwnode_phylink_pcs_get_from_fwnode(struct fwnode_handle *fwnode, + struct fwnode_handle *pcs_fwnode) +{ + return ERR_PTR(-ENOENT); +} + static inline unsigned int fwnode_phylink_pcs_count(struct fwnode_handle *fwnode) { return 0; -- 2.53.0