From patchwork Tue Nov 14 09:07:33 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Romain Gantois X-Patchwork-Id: 743890 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (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 B6FE416414; Tue, 14 Nov 2023 09:08:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="AbvX2tn/" Received: from relay6-d.mail.gandi.net (relay6-d.mail.gandi.net [IPv6:2001:4b98:dc4:8::226]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B929D1AA; Tue, 14 Nov 2023 01:08:27 -0800 (PST) Received: by mail.gandi.net (Postfix) with ESMTPSA id 63EDDC000F; Tue, 14 Nov 2023 09:08:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1699952906; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=8Fa50vvn+duinPvSNUJkisW2bIzFpaD50oi5DY2jbeU=; b=AbvX2tn/bXd5sC+lEFQ0xbvvkaIB1xrfzmwNkKJnPUdYGc9G3/wPiGRN5I669nl4P2KABk pZvKKJrP2mS2MQSvHTk4apC9vKyG+w4iQiv61clhW1t7qq00T4u242qS2xoojWe8XkzRNt mDKwDZ6bAOcBxDNBeX5spExg0ZWWICPAmdeXMtto8ipZbUBb1iCnA3n4eQHxisnaI7cvUU w1oQSij4O/RDcPyYy8o/GdiQb3PxbFfgI0xZmSiZcHOztNiSwXhGeiHojLk48fvl5xcaVz jz2b5m4GRc5UFwnU2ncpi9bBBVf9sTXPhS+tWabDpoKnMXwmgRzMyfOEes5B3w== From: Romain Gantois To: davem@davemloft.net, Rob Herring , Krzysztof Kozlowski Cc: Romain Gantois , Jakub Kicinski , Eric Dumazet , Paolo Abeni , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, thomas.petazzoni@bootlin.com, Andrew Lunn , Florian Fainelli , Heiner Kallweit , Russell King , linux-arm-kernel@lists.infradead.org, Vladimir Oltean , Luka Perkov , Robert Marko , Andy Gross , Bjorn Andersson , Konrad Dybcio Subject: [PATCH net-next v2 7/8] net: qualcomm: ipqess: add a PSGMII calibration procedure to the IPQESS driver Date: Tue, 14 Nov 2023 10:07:33 +0100 Message-ID: <20231114090743.865453-8-romain.gantois@bootlin.com> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231114090743.865453-1-romain.gantois@bootlin.com> References: <20231114090743.865453-1-romain.gantois@bootlin.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-GND-Sasl: romain.gantois@bootlin.com The IPQ4019 Ethernet Switch Subsystem uses a PSGMII link to communicate with a QCA8075 5-port PHY. This 1G link requires calibration before it can be used reliably. This commit introduces a calibration procedure followed by thourough testing of the link between each switch port and its corresponding PHY port. Signed-off-by: Romain Gantois --- drivers/net/ethernet/qualcomm/ipqess/Makefile | 2 +- .../ethernet/qualcomm/ipqess/ipqess_calib.c | 156 ++++++++++++++++++ .../ethernet/qualcomm/ipqess/ipqess_port.c | 30 ++++ .../ethernet/qualcomm/ipqess/ipqess_port.h | 4 + include/linux/dsa/qca8k.h | 1 + 5 files changed, 192 insertions(+), 1 deletion(-) create mode 100644 drivers/net/ethernet/qualcomm/ipqess/ipqess_calib.c diff --git a/drivers/net/ethernet/qualcomm/ipqess/Makefile b/drivers/net/ethernet/qualcomm/ipqess/Makefile index b12142bbc7e5..5e755af579ae 100644 --- a/drivers/net/ethernet/qualcomm/ipqess/Makefile +++ b/drivers/net/ethernet/qualcomm/ipqess/Makefile @@ -5,4 +5,4 @@ obj-$(CONFIG_QCOM_IPQ4019_ESS) += ipqess.o -ipqess-objs := ipqess_port.o ipqess_switch.o ipqess_edma.o ipqess_ethtool.o ipqess_notifiers.o +ipqess-objs := ipqess_port.o ipqess_switch.o ipqess_edma.o ipqess_ethtool.o ipqess_notifiers.o ipqess_calib.o diff --git a/drivers/net/ethernet/qualcomm/ipqess/ipqess_calib.c b/drivers/net/ethernet/qualcomm/ipqess/ipqess_calib.c new file mode 100644 index 000000000000..da9d492ca7eb --- /dev/null +++ b/drivers/net/ethernet/qualcomm/ipqess/ipqess_calib.c @@ -0,0 +1,156 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Calibration procedure for the IPQ4019 PSGMII link + * + * Copyright (C) 2009 Felix Fietkau + * Copyright (C) 2011-2012, 2020-2021 Gabor Juhos + * Copyright (c) 2015, 2019, The Linux Foundation. All rights reserved. + * Copyright (c) 2016 John Crispin + * Copyright (c) 2022 Robert Marko + * Copyright (c) 2023 Romain Gantois + */ + +#include +#include +#include +#include +#include + +#include "ipqess_port.h" +#include "ipqess_switch.h" + +/* Nonstandard MII registers for the psgmii + * device on the IPQ4019 MDIO bus. + */ + +#define PSGMII_RSTCTRL 0x0 /* Reset control register */ +#define PSGMII_RSTCTRL_RST BIT(6) +#define PSGMII_RSTCTRL_RX20 BIT(2) /* Fix/release RX 20 bit */ + +#define PSGMII_CDRCTRL 0x1a /* Clock and data recovery control register */ +#define PSGMII_CDRCTRL_RELEASE BIT(12) + +/* Retry policy */ + +#define PSGMII_CALIB_RETRIES 50 +#define PSGMII_CALIB_RETRIES_BURST 5 +#define PSGMII_CALIB_RETRY_DELAY 100 + +/* PSGMII PHY specific definitions */ +#define PSGMII_VCO_CALIB_INTERVAL 1000000 +#define PSGMII_VCO_CALIB_TIMEOUT 10000 + +static void ipqess_port_unprep_test(struct ipqess_port *port) +{ + struct qca8k_priv *priv = port->sw->priv; + /* disable loopback on switch port */ + qca8k_clear_bits(priv, QCA8K_PORT_LOOKUP_CTRL(port->index), + QCA8K_PORT_LOOKUP_LOOPBACK_EN); + + qca8k_write(priv, QCA8K_REG_PORT_STATUS(port->index), 0); + qca8k_rmw(priv, QCA8K_PORT_LOOKUP_CTRL(port->index), + QCA8K_PORT_LOOKUP_STATE_DISABLED, + QCA8K_PORT_LOOKUP_STATE_DISABLED); +} + +static void ipqess_port_prep_test(struct ipqess_port *port) +{ + struct qca8k_priv *priv = port->sw->priv; + + qca8k_write(priv, QCA8K_REG_PORT_STATUS(port->index), + QCA8K_PORT_STATUS_SPEED_1000 + | QCA8K_PORT_STATUS_TXMAC + | QCA8K_PORT_STATUS_RXMAC + | QCA8K_PORT_STATUS_DUPLEX); + + qca8k_rmw(priv, QCA8K_PORT_LOOKUP_CTRL(port->index), + QCA8K_PORT_LOOKUP_STATE_FORWARD, + QCA8K_PORT_LOOKUP_STATE_FORWARD); + + /* put switch port in loopback */ + qca8k_set_bits(priv, QCA8K_PORT_LOOKUP_CTRL(port->index), + QCA8K_PORT_LOOKUP_LOOPBACK_EN); +} + +static int psgmii_vco_calibrate(struct ipqess_port *port) +{ + struct ipqess_switch *sw = port->sw; + struct qca8k_priv *priv = sw->priv; + struct ipqess_port *other_port; + int val, ret, i; + + ret = phy_start_calibration(port->netdev->phydev); + if (ret) { + dev_err(priv->dev, + "PHY VCO calibration PLL not ready\n"); + return ret; + } + + /* Start PSGMIIPHY VCO PLL calibration */ + ret = regmap_set_bits(priv->psgmii, + PSGMIIPHY_VCO_CALIBRATION_CONTROL_REGISTER_1, + PSGMIIPHY_REG_PLL_VCO_CALIB_RESTART); + + /* Poll for PSGMIIPHY PLL calibration finish - Dakota(IPQ40xx) */ + ret = regmap_read_poll_timeout(priv->psgmii, + PSGMIIPHY_VCO_CALIBRATION_CONTROL_REGISTER_2, + val, + val & PSGMIIPHY_REG_PLL_VCO_CALIB_READY, + PSGMII_VCO_CALIB_INTERVAL, + PSGMII_VCO_CALIB_TIMEOUT); + if (ret) { + dev_err(priv->dev, + "IPQ PSGMIIPHY VCO calibration PLL not ready\n"); + return ret; + } + + /* Prepare all switch ports, in case we're dealing with a multiport PHY */ + for (i = 0; i < IPQESS_SWITCH_MAX_PORTS; i++) { + other_port = sw->port_list[i]; + if (!other_port) + continue; + ipqess_port_prep_test(other_port); + } + + ret = phy_stop_calibration(port->netdev->phydev); + + for (i = 0; i < IPQESS_SWITCH_MAX_PORTS; i++) { + other_port = sw->port_list[i]; + if (!other_port) + continue; + ipqess_port_unprep_test(other_port); + } + + qca8k_fdb_flush(priv); + + return ret; +} + +int psgmii_calibrate_and_test(struct ipqess_port *port) +{ + int ret, attempt; + + for (attempt = 0; attempt <= PSGMII_CALIB_RETRIES; attempt++) { + ret = psgmii_vco_calibrate(port); + if (!ret) { + netdev_dbg(port->netdev, + "PSGMII link stabilized after %d attempts\n", + attempt + 1); + return 0; + } + + /* On tested hardware, the link often stabilizes in 4 or 5 retries. + * If it still isn't stable, we wait a bit, then try another set + * of calibration attempts. + */ + netdev_dbg(port->netdev, "PSGMII link is unstable! Retrying... %d/QCA8K_PSGMII_CALIB_RETRIES\n", + attempt + 1); + if (attempt % PSGMII_CALIB_RETRIES_BURST == 0) + schedule_timeout_interruptible(msecs_to_jiffies(PSGMII_CALIB_RETRY_DELAY)); + else + schedule(); + } + + netdev_err(port->netdev, "PSGMII work is unstable! Repeated recalibration attempts did not help!\n"); + return -EFAULT; +} diff --git a/drivers/net/ethernet/qualcomm/ipqess/ipqess_port.c b/drivers/net/ethernet/qualcomm/ipqess/ipqess_port.c index 29420820c3d8..ea759707335a 100644 --- a/drivers/net/ethernet/qualcomm/ipqess/ipqess_port.c +++ b/drivers/net/ethernet/qualcomm/ipqess/ipqess_port.c @@ -1218,6 +1218,26 @@ int ipqess_port_check_8021q_upper(struct net_device *netdev, /* phylink ops */ +static int +ipqess_psgmii_configure(struct ipqess_port *port) +{ + int ret = 0; + + /* For this multi-port PHY, we only need one calibration run, + * don't rerun it for other ports + */ + if (!atomic_cmpxchg(&port->sw->priv->psgmii_calibrated, 0, 1)) { + psgmii_calibrate_and_test(port); + + ret = regmap_clear_bits(port->sw->priv->psgmii, PSGMIIPHY_MODE_CONTROL, + PSGMIIPHY_MODE_ATHR_CSCO_MODE_25M); + ret = regmap_write(port->sw->priv->psgmii, PSGMIIPHY_TX_CONTROL, + PSGMIIPHY_TX_CONTROL_MAGIC_VALUE); + } + + return ret; +} + static void ipqess_phylink_mac_config(struct phylink_config *config, unsigned int mode, @@ -1233,12 +1253,22 @@ ipqess_phylink_mac_config(struct phylink_config *config, case 1: case 2: case 3: + if (state->interface == PHY_INTERFACE_MODE_PSGMII) + if (ipqess_psgmii_configure(port)) + dev_err(priv->dev, + "PSGMII configuration failed!\n"); + return; case 4: case 5: if (phy_interface_mode_is_rgmii(state->interface)) regmap_set_bits(priv->regmap, QCA8K_IPQ4019_REG_RGMII_CTRL, QCA8K_IPQ4019_RGMII_CTRL_CLK); + + if (state->interface == PHY_INTERFACE_MODE_PSGMII) + if (ipqess_psgmii_configure(port)) + dev_err(priv->dev, + "PSGMII configuration failed!\n"); return; default: dev_err(priv->dev, "%s: unsupported port: %i\n", __func__, diff --git a/drivers/net/ethernet/qualcomm/ipqess/ipqess_port.h b/drivers/net/ethernet/qualcomm/ipqess/ipqess_port.h index 00f0dff9c39d..bc24a0507702 100644 --- a/drivers/net/ethernet/qualcomm/ipqess/ipqess_port.h +++ b/drivers/net/ethernet/qualcomm/ipqess/ipqess_port.h @@ -95,4 +95,8 @@ int ipqess_port_obj_del(struct net_device *netdev, const void *ctx, bool ipqess_port_offloads_bridge_port(struct ipqess_port *port, const struct net_device *netdev); + +/* Defined in ipqess_calib.c */ +int psgmii_calibrate_and_test(struct ipqess_port *port); + #endif diff --git a/include/linux/dsa/qca8k.h b/include/linux/dsa/qca8k.h index 9ad016f7201e..72c488e7c498 100644 --- a/include/linux/dsa/qca8k.h +++ b/include/linux/dsa/qca8k.h @@ -496,6 +496,7 @@ struct qca8k_priv { /* IPQ4019 specific */ struct regmap *psgmii; + atomic_t psgmii_calibrated; }; struct qca8k_mib_desc {