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: 13565573 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 9F9E1C48BC3 for ; Wed, 21 Feb 2024 13:04:21 +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:In-Reply-To:References:Message-Id :MIME-Version:Subject:Date:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=7qYuIMopzCnZH+3g6y57gBux7HX9DQgNCOx+4ksaBoQ=; b=MgHZwEbZdd9Zpi HIJe/rsI5Zw/CchJbeDYHzXIN0hzDqZTLYKkGghMVxgBTL2KtZHm3VafuKW+GEFxfjbuXIqZyHEFL YtVTMKMMPUQE6oVMrktstzbFrPDxpw4nKhpMbxj8czY5bFatrT644RaU2fG5tWWRQNOpfRym9Wegq ee0108DD/1CxpZxtpNO6sx3LyiSuW1YEvf/GMwFZjn/m3lN0RHLkohwydr8tAmWU0OfCfQe1m+db6 bKVmiuOy7aIIDaY4GXndzNigu62pXr8CjAxLddKNgnZSSHGHV5ruBmXHn2k2J5+3yC35jNcXjyjaW Zi4ROWPu7deGE0CU0QFw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rcmGd-00000000xCi-2qQz; Wed, 21 Feb 2024 13:04:07 +0000 Received: from relay4-d.mail.gandi.net ([217.70.183.196]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rcmGX-00000000x8g-3yY4 for linux-arm-kernel@lists.infradead.org; Wed, 21 Feb 2024 13:04:04 +0000 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 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-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240221_050402_451534_4FFA75A9 X-CRM114-Status: GOOD ( 22.59 ) 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 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 *);