From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=209.85.128.49 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794653094; b=dY02oawyuvPhDECAbLwGaIeawjh8bDFUWvF34q2NQSTtTMIw9m8wWwjMu9vKVo0RFV/U hsEB+ajn/HUtMX4QsG/OH1nMOehq2IAXn0S041anUAj1ds65b/OO55G8Yy/ABUX0999gc 1wJq04BJ7EkQhIHGOrMx2O5YF4sozQDp3/Tw1ovFSVYmnh9Fdh8Cm/C2pYvlfwqT31N+n IY0vRC5kzMaDnZ7z9jOh5u9lFOSnDUN/Qw7oJ8TyIl2V774DmA6fX1zOfXo4CgYHbU6mZ ROS15pfBJOygukXQhXxQ03I0agRc6niU6Z486rHbguONY5XgXMmLWg4Sk3cFwO553QQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794653094; h=DMARC-Filter:Received:DKIM-Signature:X-Google-DKIM-Signature: X-Forwarded-Encrypted:X-Gm-Message-State:X-Gm-Gg:X-Received:Received: From:To:Subject:Date:Message-ID:X-Mailer:In-Reply-To:References: MIME-Version:Content-Transfer-Encoding; bh=ob2EIo0m2AuP+fLPWE6b5DDf72VtjDVDoAlCmtfRBv4=; b=VseWVslhi/robokyrRtjpCdJbVE0bgMUUlu0Cf/EerCzOUoSNytuWt9qumTzU+xpvZgT +fSda16KVxIKmdiEeDinyb0M6bECr4331SPNv+yRAh2UvDQbssm351t/NLCs9RVC0x9aL LozU+Z/xT+0ejrEfRzkykoVSim2zlGJEeYytCm01bBkl62Zziq5cVcTqF7KbCDksgzefZ G74huMgwBnNWcUggNwZJoVEw/XkHDB/pxF6BxLav/kVQ+uVWjY7O2L7BFyDITqLlJZAzT abNF+wQmTI8zk6A8hSL7LJpGVboxsPofpj5dS9DwI2ghSU0Pc29lbUaZgALcos2up2g== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20260707 header.b=kyPpHPsj; arc=none smtp.remote-ip=209.85.128.49 Received: from mail-wm1-f49.google.com (mail-wm1-f49.google.com [209.85.128.49]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 78E2660A6F6D for ; Sat, 14 Nov 2026 10:44:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 78E2660A6F6D 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.a=rsa-sha256 header.s=20260707 header.b=kyPpHPsj Received: by mail-wm1-f49.google.com with SMTP id 5b1f17b1804b1-4ac95761c85so10770485e9.2 for ; Sat, 14 Nov 2026 02:44:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20260707; t=1794653092; x=1795257892; 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=ob2EIo0m2AuP+fLPWE6b5DDf72VtjDVDoAlCmtfRBv4=; b=kyPpHPsjY+RKpyWV5CfTT3NwFqtuaiNG8+3sX988IRpgAR294pH3gAAlmhUCR8SEIM gUSAVRAuWvqyD8kiR6jlWc0URwyK6vn1uJgVcT5aSivHdQ2lQNVI2u0bgnkFYbJ7h53E AgnItRl3vBlcQmsdb7stDpCTTGR9lhvqQWQL/O6rWjfDFt+FBvROFw9Jxx8xuqDOyfED TvM938wuVvBvqFqL/aMxp2PwKO8GIPMF5Qx7nak/0joQDGC4ggKpJWMZGw91nRMsRAS+ 8yn3yrnuemBPhl4f8AVXuFx943avBGB11UPAFX/j8VVwGlo/nAP4FYgIO70sx2lmagN2 GxMQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1794653092; x=1795257892; 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=ob2EIo0m2AuP+fLPWE6b5DDf72VtjDVDoAlCmtfRBv4=; b=o4ZJhxX/UnE9yiyngfHZBBR7vK6fJp+ttZsTIDU7oNExYubyR+GYZd/lBp74Q/+L52 1abfSuCcshJjFqksrtMEoqWND7bvWn+LXZDV2PaD1XB2SgrRsNcCV8n24jThquYFQSS1 MUAamvZ/XKsai2a9ljps2s57vAFtb3L1LI4xFhgpfvL1mmDyQQJTqxqLtYktmTSCKPDv Sx59txsddyDP6qOtL37CehKyZDF4jD4USpLLhibj2ADi/cpIcxdrXIr35m0VjPcI3cpQ KvSxHuEFlHiMh6RYasE+4/XiUfju2RY8DfoYWro7p2RJYhaEhaC4wvt72eeuHgFKc3WJ 0aPw== X-Forwarded-Encrypted: i=1; AL+hErEr6tum6cUkBpvKuhyk4u6hA9KWzkKknKCNRK2tJicwahU/nBt6fIjwUdBz417+EPZLbqDXq7/NulE=@vger.kernel.org X-Gm-Message-State: APuU4Z8LYHSpa78dmt65RbLbB2Ou/CB4IRWB+iPQVuaUz3Eyj1QEJaXN HMkzmrXmo28KpRMC6oMuhdAl6OdOOc/RVu1FPNsVXWAL5A2GM+ojX5D3 X-Gm-Gg: AYBFou3SNSGUtUmFZgmqON10hcLAPNfRfWNx1yYpmFujJEwLQAnPfRWVQ1RTIe0zyJ/ nFP2kN0pymt80LpyO5uVUh/l/UTsUAAeIFTvNps9DBsJVkyVP+MULRY+5Yc4D4X2PuzClITEcHs n/B3hWHnQsucZKRSgNUw45bC7TGf1WlQR08wpx4sAxJsRABLoC5+eMJLu00unDO/C6kQsWh5Qzk NNsWKc2nu5UYcuXVN4XdFMOLchyRHpyrGa3tz+gDQ60ucKIeurN4b3JKMQU0yQ43ukFxi1MLap1 aMlCFiw20wzSFOv7d/z1gOcOvPH8F0rVuV3IhsQ4VDb1qRDDw12jnRsWQkN4fupfVzHQaytBsH9 OlCcJP/ZciHEE1CHTFXG03ShIhNjqxQXhU4UYUiGsLyjM1QJp5I3TKngN503nRlUy1QzvAlAd18 0q23ZFRGpadzlh/PKkho1zFsydTIbdXFEoDo1FvT8c9iwpf/bUJ8GDLEqZeuj9lws6vs1hwiDCt 9IHMZ8sAka7OVSnHdqSRGgAjpaGLrZYMbbp4g33ARizDhFKUyWFxux8RZeDedWYVlR2h4hAsHwN Gk2z15cp2bOdoM/Eh6Ot0eg8RNhaqLa8HuVuPDhJWK5al2bR59Z6AAvHetJIxZGzPPz1XQWtdOf Nk1RRSAGRWdzMfc4Yr+oPRWeUrtegV5nfrQ== X-Received: by 2002:a05:600c:548e:b0:4bb:5c92:ce12 with SMTP id 5b1f17b1804b1-4bb5c92cedemr72677785e9.17.1794653091746; Sat, 14 Nov 2026 02:44:51 -0800 (PST) Received: from Ansuel-XPS24.localdomain (93-34-92-103.ip49.fastwebnet.it. [93.34.92.103]) by smtp.googlemail.com with ESMTPSA id 5b1f17b1804b1-4bb56719391sm52858285e9.1.2026.11.14.02.44.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 14 Nov 2026 02:44:51 -0800 (PST) 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 , Randy Dunlap , 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 v20 09/15] net: phylink: support late PCS provider attach Date: Sat, 14 Nov 2026 11:43:48 +0100 Message-ID: <20261114104426.235620-10-ansuelsmth@gmail.com> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20261114104426.235620-1-ansuelsmth@gmail.com> References: <20261114104426.235620-1-ansuelsmth@gmail.com> X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Add support for late PCS provider attachment to a phylink instance. Similar to FWNODE_PCS_PROVIDER_DEL, FWNODE_PCS_PROVIDER_ADD is added to address the case where a PCS provider is added after a phylink instance is created and started. The PCS notifier will emit the event FWNODE_PCS_PROVIDER_ADD every time a new PCS provider is added. If a related PCS is found, then such PCS is added to the phylink instance PCS list. Such PCS is then linked to the phylink instance and the supported interfaces of the phylink instance get refreshed. If we are in a major_config_failed scenario an interface reconfiguration is triggered 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 | 22 +++++++++++ drivers/net/phy/phylink.c | 80 +++++++++++++++++++++++++++++---------- include/linux/pcs/pcs.h | 31 +++++++++++++++ 3 files changed, 114 insertions(+), 19 deletions(-) diff --git a/drivers/net/pcs/pcs.c b/drivers/net/pcs/pcs.c index 25b3248e8b93..fef560eddf2a 100644 --- a/drivers/net/pcs/pcs.c +++ b/drivers/net/pcs/pcs.c @@ -69,6 +69,10 @@ fwnode_pcs_add_provider(struct fwnode_handle *fwnode, mutex_unlock(&fwnode_pcs_mutex); + blocking_notifier_call_chain(&fwnode_pcs_notify_list, + FWNODE_PCS_PROVIDER_ADD, + pp); + pr_debug("Added pcs provider from %pfwf\n", fwnode); return pp; @@ -201,6 +205,24 @@ struct phylink_pcs *fwnode_pcs_get(const struct fwnode_handle *fwnode, unsigned } EXPORT_SYMBOL_GPL(fwnode_pcs_get); +struct phylink_pcs *fwnode_pcs_get_from_provider(struct fwnode_pcs_provider *provider, + const struct fwnode_handle *fwnode, + int index) +{ + struct fwnode_reference_args pcsspec; + struct phylink_pcs *pcs; + int ret; + + ret = fwnode_parse_pcsspec(fwnode, index, NULL, &pcsspec); + if (ret) + return ERR_PTR(ret); + + pcs = __fwnode_pcs_get_from_pcsspec_provider(&pcsspec, provider); + fwnode_handle_put(pcsspec.fwnode); + return pcs; +} +EXPORT_SYMBOL_GPL(fwnode_pcs_get_from_provider); + bool fwnode_pcs_matches_provider(struct fwnode_pcs_provider *provider, const struct fwnode_handle *fwnode, struct phylink_pcs *pl_pcs) diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c index f8fc52c73646..2bf7a1ecebd6 100644 --- a/drivers/net/phy/phylink.c +++ b/drivers/net/phy/phylink.c @@ -2043,6 +2043,35 @@ int phylink_set_fixed_link(struct phylink *pl, } EXPORT_SYMBOL_GPL(phylink_set_fixed_link); +static bool 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); + + /* Make sure PCS is not already in the list */ + list_for_each_entry(tmp, &pl->pcs_list, list) + if (tmp == pcs) + return false; + + if (WARN(rcu_access_pointer(pcs->phylink), + "%s: PCS already attached to a phylink instance\n", + __func__)) + return false; + + list_add_tail(&pcs->list, &pl->pcs_list); + + /* Link PCS to phylink */ + rcu_assign_pointer(pcs->phylink, pl); + + return true; +} + static int phylink_fill_available_pcs(struct phylink *pl, struct phylink_config *config) { @@ -2075,12 +2104,7 @@ static int phylink_fill_available_pcs(struct phylink *pl, if (!pcs) continue; - if (WARN(rcu_access_pointer(pcs->phylink), - "%s: PCS already attached to a phylink instance\n", - __func__)) - continue; - - list_add_tail(&pcs->list, &pl->pcs_list); + phylink_add_pcs(pl, pcs); } out: @@ -2127,20 +2151,42 @@ static int pcs_provider_notify(struct notifier_block *self, struct fwnode_pcs_provider *pp = data; struct phylink_pcs *pcs, *tmp; bool resolve = false; + int count, i; rtnl_lock(); mutex_lock(&pl->state_mutex); - /* - * Loop all the PCS for phylink instance and check if - * this notification is relevant for some of them. - */ - list_for_each_entry_safe(pcs, tmp, &pl->pcs_list, list) { - if (!fwnode_pcs_matches_provider(pp, pl->fwnode, pcs)) - continue; + switch (val) { + case FWNODE_PCS_PROVIDER_ADD: + count = fwnode_phylink_pcs_count(pl->fwnode); + for (i = 0; i < count; i++) { + pcs = fwnode_pcs_get_from_provider(pp, pl->fwnode, i); + if (IS_ERR_OR_NULL(pcs)) + continue; + + /* Trigger a resolve only if a PCS is actually added */ + if (phylink_add_pcs(pl, pcs)) + resolve = true; + } + + /* Force an interface reconfig if major config fail */ + if (resolve && pl->major_config_failed) + pl->force_major_config = true; - phylink_del_pcs(pl, pcs); - resolve = true; + break; + case FWNODE_PCS_PROVIDER_DEL: + /* + * Loop all the PCS for phylink instance and check if + * this notification is relevant for some of them. + */ + list_for_each_entry_safe(pcs, tmp, &pl->pcs_list, list) { + if (!fwnode_pcs_matches_provider(pp, pl->fwnode, pcs)) + continue; + + phylink_del_pcs(pl, pcs); + resolve = true; + } + break; } /* Exit early if nothing has changed */ @@ -2392,10 +2438,6 @@ struct phylink *phylink_create(struct phylink_config *config, mutex_lock(&pl->state_mutex); - /* Link available PCS to phylink */ - list_for_each_entry(pcs, &pl->pcs_list, list) - rcu_assign_pointer(pcs->phylink, pl); - phy_interface_copy(pl->supported_interfaces, pl->config->supported_interfaces); diff --git a/include/linux/pcs/pcs.h b/include/linux/pcs/pcs.h index 83e0a2ad4b09..00a636c82c65 100644 --- a/include/linux/pcs/pcs.h +++ b/include/linux/pcs/pcs.h @@ -5,6 +5,7 @@ #include enum fwnode_pcs_notify_event { + FWNODE_PCS_PROVIDER_ADD, FWNODE_PCS_PROVIDER_DEL, }; @@ -50,6 +51,28 @@ int unregister_fwnode_pcs_notifier(struct notifier_block *nb); struct phylink_pcs *fwnode_pcs_get(const struct fwnode_handle *fwnode, unsigned int index); +/** + * fwnode_pcs_get_from_provider() - Retrieve a PCS from a specific provider + * @provider: PCS provider to use + * @fwnode: firmware node + * @index: index fwnode PCS handle in firmware node + * + * Get a PCS from the firmware node at index specifically provided by + * passed PCS provider. + * + * Unlike fwnode_pcs_get(), this function does not search the global list of + * PCS providers. The caller must provide the provider responsible for the + * referenced PCS. + * + * Returns: a pointer to the phylink_pcs or a negative error pointer. Can + * return -ENODEV 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) or + * can return -EINVAL if the PCS provider doesn't expose any PCS for the fwnode. + */ +struct phylink_pcs *fwnode_pcs_get_from_provider(struct fwnode_pcs_provider *provider, + const struct fwnode_handle *fwnode, + int index); + /** * fwnode_pcs_matches_provider() - Check whether a PCS belongs to a provider * @provider: PCS provider to check @@ -120,6 +143,14 @@ static inline struct phylink_pcs *fwnode_pcs_get(const struct fwnode_handle *fwn return ERR_PTR(-ENOENT); } +static inline struct phylink_pcs * +fwnode_pcs_get_from_provider(struct fwnode_pcs_provider *provider, + const struct fwnode_handle *fwnode, + int index) +{ + return ERR_PTR(-ENOENT); +} + static inline bool fwnode_pcs_matches_provider(struct fwnode_pcs_provider *provider, const struct fwnode_handle *fwnode, struct phylink_pcs *pl_pcs) -- 2.55.0