From patchwork Wed Feb 21 13:04:19 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Romain Gantois X-Patchwork-Id: 13565566 X-Patchwork-Delegate: kuba@kernel.org Received: from relay4-d.mail.gandi.net (relay4-d.mail.gandi.net [217.70.183.196]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7FB174F885; Wed, 21 Feb 2024 13:04:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.183.196 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708520647; cv=none; b=V4vZ5qWkBAefKqqWuN2uWZ0U43L3EM+V3gvTmkJ+SqSoy0Rg9ZfESqOYXTGWU8U3YyQ5tMV26psCd0cd9Jr50L38sTrbjhEPPeBcKRna7+EvawfOK/TyBXAI/zych0Z3urt2O9fS82kW4j0DJwo/FhckXB0qie6h5+sycczaJns= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708520647; c=relaxed/simple; bh=W4kwxjanPnBMQEebBImaSu8oin1Isnonpi0RAYuh2vs=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=sl1o166xGMIu/vGhQhTFTFGhseQ7RZbuwJu9XU8J9GuUzLQbBabYb4pjii1GJWjFUl26brT+xsqvbsCKcI28528QJkAt0J9IgPBc9QMyQJW3a9EKVQ9T8zh6jDr5v2o4Nd64uy8soPgFESQiBwupDI70n9+1Nj9nyJXHwYI5df8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=NID9xw5K; arc=none smtp.client-ip=217.70.183.196 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="NID9xw5K" Received: by mail.gandi.net (Postfix) with ESMTPSA id 26705E0004; Wed, 21 Feb 2024 13:03:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1708520640; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=TihZ+E5bRCt9eqbBQ5SrGYKdzNeo69DFCWBLyHM4SoE=; b=NID9xw5KJjHVsZnbq58Nox6xZOGQjitn2OssuAS0zkc0NZWwpPzSRxM/JQzkrbMBYoClWh zZMNeyaawLNvvs+bnEmUNUQj5a4PcAzUNSrnomR38DaMZYRRtVo032hTcDuGCjiscqIT0w TWAX2YNJO9rfHemGu9nHDdXXJmci+i/ekrLp+9kjnPrEFgfOgzwvrgkhEzVIy8Rl3p1iWB KRSRLHYP/sNxp9DqAbtFJayCZdSqpgJ1SYOxTXYceS9eqKmgkAXm/Qb5hmNm7XR9ASnfTI cGvVXMdJ0GLgbnvlCK0kELK+LLLS4LpBiyEDf8/Ke3mLOi2l5ghGSZYTmnRR7A== From: Romain Gantois Date: Wed, 21 Feb 2024 14:04:19 +0100 Subject: [PATCH net-next v4 2/7] net: phylink: add rxc_always_on flag to phylink_pcs Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20240221-rxc_bugfix-v4-2-4883ee1cc7b1@bootlin.com> References: <20240221-rxc_bugfix-v4-0-4883ee1cc7b1@bootlin.com> In-Reply-To: <20240221-rxc_bugfix-v4-0-4883ee1cc7b1@bootlin.com> To: Russell King , Andrew Lunn , Heiner Kallweit , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Alexandre Torgue , Jose Abreu , Maxime Coquelin , =?utf-8?b?Q2zDqW1lbnQgTMOp?= =?utf-8?b?Z2Vy?= Cc: Maxime Chevallier , Miquel Raynal , Thomas Petazzoni , netdev@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-renesas-soc@vger.kernel.org, Romain Gantois X-Mailer: b4 0.12.4 X-GND-Sasl: romain.gantois@bootlin.com X-Patchwork-Delegate: kuba@kernel.org Some MAC drivers (e.g. stmmac) require a continuous receive clock signal to be generated by a PCS that is handled by a standalone PCS driver. Such a PCS driver does not have access to a PHY device, thus cannot check the PHY_F_RXC_ALWAYS_ON flag. They cannot check max_requires_rxc in the phylink config either, since it is a private member. Therefore, a new flag is needed to signal to the PCS that it should keep the RX clock signal up at all times. Suggested-by: Russell King Signed-off-by: Romain Gantois --- drivers/net/phy/phylink.c | 14 ++++++++++++++ include/linux/phylink.h | 38 ++++++++++++++++++++++++++++++++++++++ 2 files changed, 52 insertions(+) diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c index 2bb583543dea..dad7462996ab 100644 --- a/drivers/net/phy/phylink.c +++ b/drivers/net/phy/phylink.c @@ -1042,6 +1042,20 @@ static void phylink_pcs_poll_start(struct phylink *pl) mod_timer(&pl->link_poll, jiffies + HZ); } +int phylink_pcs_pre_init(struct phylink *pl, struct phylink_pcs *pcs) +{ + int ret = 0; + + /* Signal to PCS driver that MAC requires RX clock for init */ + if (pl->config->mac_requires_rxc) + pcs->rxc_always_on = true; + + if (pcs->ops->pcs_pre_init) + ret = pcs->ops->pcs_pre_init(pcs); + + return ret; +} + static void phylink_mac_config(struct phylink *pl, const struct phylink_link_state *state) { diff --git a/include/linux/phylink.h b/include/linux/phylink.h index 019993e5f570..f6ef5bc82179 100644 --- a/include/linux/phylink.h +++ b/include/linux/phylink.h @@ -396,6 +396,10 @@ struct phylink_pcs_ops; * @phylink: pointer to &struct phylink_config * @neg_mode: provide PCS neg mode via "mode" argument * @poll: poll the PCS for link changes + * @rxc_always_on: The MAC driver requires the reference clock + * to always be on. Standalone PCS drivers which + * do not have access to a PHY device can check + * this instead of PHY_F_RXC_ALWAYS_ON. * * This structure is designed to be embedded within the PCS private data, * and will be passed between phylink and the PCS. @@ -408,6 +412,7 @@ struct phylink_pcs { struct phylink *phylink; bool neg_mode; bool poll; + bool rxc_always_on; }; /** @@ -422,6 +427,8 @@ struct phylink_pcs { * @pcs_an_restart: restart 802.3z BaseX autonegotiation. * @pcs_link_up: program the PCS for the resolved link configuration * (where necessary). + * @pcs_pre_init: configure PCS components necessary for MAC hardware + * initialization e.g. RX clock for stmmac. */ struct phylink_pcs_ops { int (*pcs_validate)(struct phylink_pcs *pcs, unsigned long *supported, @@ -441,6 +448,7 @@ struct phylink_pcs_ops { void (*pcs_an_restart)(struct phylink_pcs *pcs); void (*pcs_link_up)(struct phylink_pcs *pcs, unsigned int neg_mode, phy_interface_t interface, int speed, int duplex); + int (*pcs_pre_init)(struct phylink_pcs *pcs); }; #if 0 /* For kernel-doc purposes only. */ @@ -549,6 +557,34 @@ void pcs_an_restart(struct phylink_pcs *pcs); */ void pcs_link_up(struct phylink_pcs *pcs, unsigned int neg_mode, phy_interface_t interface, int speed, int duplex); + +/** + * pcs_pre_init() - Configure PCS components necessary for MAC initialization + * @pcs: a pointer to a &struct phylink_pcs. + * + * This function can be called by MAC drivers through the + * phylink_pcs_pre_init() wrapper, before their hardware is initialized. It + * should not be called after the link is brought up, as reconfiguring the PCS + * at this point could break the link. + * + * Some MAC devices require specific hardware initialization to be performed by + * their associated PCS device before they can properly initialize their own + * hardware. An example of this is the initialization of stmmac controllers, + * which requires an active REF_CLK signal to be provided by the PHY/PCS. + * + * By calling phylink_pcs_pre_init(), MAC drivers can ensure that the PCS is + * setup in a way that allows for successful hardware initialization. + * + * The specific configuration performed by pcs_pre_init() is dependent on the + * model of PCS and the requirements of the MAC device attached to it. PCS + * driver authors should consider whether their target device is to be used in + * conjunction with a MAC device whose driver calls phylink_pcs_pre_init(). MAC + * driver authors should document their requirements for the PCS + * pre-initialization. + * + */ +int pcs_config(struct phylink_pcs *pcs); + #endif struct phylink *phylink_create(struct phylink_config *, @@ -568,6 +604,8 @@ void phylink_disconnect_phy(struct phylink *); void phylink_mac_change(struct phylink *, bool up); void phylink_pcs_change(struct phylink_pcs *, bool up); +int phylink_pcs_pre_init(struct phylink *pl, struct phylink_pcs *pcs); + void phylink_start(struct phylink *); void phylink_stop(struct phylink *);