From nobody Sun Dec 22 12:03:29 2024 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 653B8C77B7A for ; Thu, 1 Jun 2023 14:15:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233389AbjFAOPZ (ORCPT ); Thu, 1 Jun 2023 10:15:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36622 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234187AbjFAOPR (ORCPT ); Thu, 1 Jun 2023 10:15:17 -0400 Received: from relay7-d.mail.gandi.net (relay7-d.mail.gandi.net [217.70.183.200]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3BE051A7; Thu, 1 Jun 2023 07:15:08 -0700 (PDT) X-GND-Sasl: maxime.chevallier@bootlin.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1685628906; 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=CGAXWRYvf80zHfIhDzB2tu6kKP2+wfCv2aHqFygA5hI=; b=FXoW95C+Tqzworwca9UAfYyxbxSAmRkvLWDCrxm8wYO9MfFoZC4O9CwRasskE3dFXlNpX6 gF3ziMoisDW/3XRZpRu4670JSP3718amRQoR8Z3k3jiGvw17cUARrjWxG2LdLUdNCIkAgf 8+X3BLstbgLyhPmF/JIgBepnCdUdykAo78/2dSRErGwAKJENSzpq5F2UldShtGjOftR1II RZ+aKqUfoqpJcAI4oCM4NdYJvRaJCTd6sWh4mWuQMP8I4qs1oZeKFRULTD8is11syPVUEa Sd9Z2V//BVAkPsajLtUY5g3yei7YjXQHo8r8SprtTiyFMduTFdDKVrgzMM7D4Q== X-GND-Sasl: maxime.chevallier@bootlin.com X-GND-Sasl: maxime.chevallier@bootlin.com X-GND-Sasl: maxime.chevallier@bootlin.com X-GND-Sasl: maxime.chevallier@bootlin.com X-GND-Sasl: maxime.chevallier@bootlin.com X-GND-Sasl: maxime.chevallier@bootlin.com X-GND-Sasl: maxime.chevallier@bootlin.com X-GND-Sasl: maxime.chevallier@bootlin.com X-GND-Sasl: maxime.chevallier@bootlin.com X-GND-Sasl: maxime.chevallier@bootlin.com X-GND-Sasl: maxime.chevallier@bootlin.com X-GND-Sasl: maxime.chevallier@bootlin.com X-GND-Sasl: maxime.chevallier@bootlin.com X-GND-Sasl: maxime.chevallier@bootlin.com X-GND-Sasl: maxime.chevallier@bootlin.com X-GND-Sasl: maxime.chevallier@bootlin.com X-GND-Sasl: maxime.chevallier@bootlin.com X-GND-Sasl: maxime.chevallier@bootlin.com X-GND-Sasl: maxime.chevallier@bootlin.com X-GND-Sasl: maxime.chevallier@bootlin.com X-GND-Sasl: maxime.chevallier@bootlin.com X-GND-Sasl: maxime.chevallier@bootlin.com Received: by mail.gandi.net (Postfix) with ESMTPSA id 57CB320008; Thu, 1 Jun 2023 14:15:02 +0000 (UTC) From: Maxime Chevallier To: Mark Brown , davem@davemloft.net Cc: Maxime Chevallier , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, alexis.lothore@bootlin.com, thomas.petazzoni@bootlin.com, Andrew Lunn , Jakub Kicinski , Eric Dumazet , Paolo Abeni , Florian Fainelli , Heiner Kallweit , Russell King , Vladimir Oltean , Ioana Ciornei , linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, Maxime Coquelin , Jose Abreu , Alexandre Torgue , Giuseppe Cavallaro , Simon Horman Subject: [PATCH net-next v4 1/4] net: mdio: Introduce a regmap-based mdio driver Date: Thu, 1 Jun 2023 16:14:51 +0200 Message-Id: <20230601141454.67858-2-maxime.chevallier@bootlin.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230601141454.67858-1-maxime.chevallier@bootlin.com> References: <20230601141454.67858-1-maxime.chevallier@bootlin.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" There exists several examples today of devices that embed an ethernet PHY or PCS directly inside an SoC. In this situation, either the device is controlled through a vendor-specific register set, or sometimes exposes the standard 802.3 registers that are typically accessed over MDIO. As phylib and phylink are designed to use mdiodevices, this driver allows creating a virtual MDIO bus, that translates mdiodev register accesses to regmap accesses. The reason we use regmap is because there are at least 3 such devices known today, 2 of them are Altera TSE PCS's, memory-mapped, exposed with a 4-byte stride in stmmac's dwmac-socfpga variant, and a 2-byte stride in altera-tse. The other one (nxp,sja1110-base-tx-mdio) is exposed over SPI. Signed-off-by: Maxime Chevallier Reviewed-by: Simon Horman --- V3->V4 : - Clarify the KConfig description with the need for REGMAP - Put the correct #include in the new header, as per Vlad's review V2->V3 : - Introduce struct mdio_regmap_priv for priv elements instead of plain reuse of the config struct - Use ~O instead of ~0UL V1->V2 : - Use phy_mask to avoid unnecessary scanning, suggested by Andrew - Allow entirely disabling scanning, suggested by Vlad MAINTAINERS | 7 +++ drivers/net/mdio/Kconfig | 11 ++++ drivers/net/mdio/Makefile | 1 + drivers/net/mdio/mdio-regmap.c | 93 ++++++++++++++++++++++++++++++++ include/linux/mdio/mdio-regmap.h | 26 +++++++++ 5 files changed, 138 insertions(+) create mode 100644 drivers/net/mdio/mdio-regmap.c create mode 100644 include/linux/mdio/mdio-regmap.h diff --git a/MAINTAINERS b/MAINTAINERS index c904dba1733b..f68269b39e09 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -12835,6 +12835,13 @@ F: Documentation/devicetree/bindings/net/ieee80215= 4/mcr20a.txt F: drivers/net/ieee802154/mcr20a.c F: drivers/net/ieee802154/mcr20a.h =20 +MDIO REGMAP DRIVER +M: Maxime Chevallier +L: netdev@vger.kernel.org +S: Maintained +F: drivers/net/mdio/mdio-regmap.c +F: include/linux/mdio/mdio-regmap.h + MEASUREMENT COMPUTING CIO-DAC IIO DRIVER M: William Breathitt Gray L: linux-iio@vger.kernel.org diff --git a/drivers/net/mdio/Kconfig b/drivers/net/mdio/Kconfig index 9ff2e6f22f3f..4a7a303be2f7 100644 --- a/drivers/net/mdio/Kconfig +++ b/drivers/net/mdio/Kconfig @@ -185,6 +185,17 @@ config MDIO_IPQ8064 This driver supports the MDIO interface found in the network interface units of the IPQ8064 SoC =20 +config MDIO_REGMAP + tristate + help + This driver allows using MDIO devices that are not sitting on a + regular MDIO bus, but still exposes the standard 802.3 register + layout. It's regmap-based so that it can be used on integrated, + memory-mapped PHYs, SPI PHYs and so on. A new virtual MDIO bus is + created, and its read/write operations are mapped to the underlying + regmap. Users willing to use this driver must explicitly select + REGMAP. + config MDIO_THUNDER tristate "ThunderX SOCs MDIO buses" depends on 64BIT diff --git a/drivers/net/mdio/Makefile b/drivers/net/mdio/Makefile index 7d4cb4c11e4e..1015f0db4531 100644 --- a/drivers/net/mdio/Makefile +++ b/drivers/net/mdio/Makefile @@ -19,6 +19,7 @@ obj-$(CONFIG_MDIO_MOXART) +=3D mdio-moxart.o obj-$(CONFIG_MDIO_MSCC_MIIM) +=3D mdio-mscc-miim.o obj-$(CONFIG_MDIO_MVUSB) +=3D mdio-mvusb.o obj-$(CONFIG_MDIO_OCTEON) +=3D mdio-octeon.o +obj-$(CONFIG_MDIO_REGMAP) +=3D mdio-regmap.o obj-$(CONFIG_MDIO_SUN4I) +=3D mdio-sun4i.o obj-$(CONFIG_MDIO_THUNDER) +=3D mdio-thunder.o obj-$(CONFIG_MDIO_XGENE) +=3D mdio-xgene.o diff --git a/drivers/net/mdio/mdio-regmap.c b/drivers/net/mdio/mdio-regmap.c new file mode 100644 index 000000000000..8a742a8d6387 --- /dev/null +++ b/drivers/net/mdio/mdio-regmap.c @@ -0,0 +1,93 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* Driver for MMIO-Mapped MDIO devices. Some IPs expose internal PHYs or P= CS + * within the MMIO-mapped area + * + * Copyright (C) 2023 Maxime Chevallier + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define DRV_NAME "mdio-regmap" + +struct mdio_regmap_priv { + struct regmap *regmap; + u8 valid_addr; +}; + +static int mdio_regmap_read_c22(struct mii_bus *bus, int addr, int regnum) +{ + struct mdio_regmap_priv *ctx =3D bus->priv; + unsigned int val; + int ret; + + if (ctx->valid_addr !=3D addr) + return -ENODEV; + + ret =3D regmap_read(ctx->regmap, regnum, &val); + if (ret < 0) + return ret; + + return val; +} + +static int mdio_regmap_write_c22(struct mii_bus *bus, int addr, int regnum, + u16 val) +{ + struct mdio_regmap_priv *ctx =3D bus->priv; + + if (ctx->valid_addr !=3D addr) + return -ENODEV; + + return regmap_write(ctx->regmap, regnum, val); +} + +struct mii_bus *devm_mdio_regmap_register(struct device *dev, + const struct mdio_regmap_config *config) +{ + struct mdio_regmap_priv *mr; + struct mii_bus *mii; + int rc; + + if (!config->parent) + return ERR_PTR(-EINVAL); + + mii =3D devm_mdiobus_alloc_size(config->parent, sizeof(*mr)); + if (!mii) + return ERR_PTR(-ENOMEM); + + mr =3D mii->priv; + mr->regmap =3D config->regmap; + mr->valid_addr =3D config->valid_addr; + + mii->name =3D DRV_NAME; + strscpy(mii->id, config->name, MII_BUS_ID_SIZE); + mii->parent =3D config->parent; + mii->read =3D mdio_regmap_read_c22; + mii->write =3D mdio_regmap_write_c22; + + if (config->autoscan) + mii->phy_mask =3D ~BIT(config->valid_addr); + else + mii->phy_mask =3D ~0; + + rc =3D devm_mdiobus_register(dev, mii); + if (rc) { + dev_err(config->parent, "Cannot register MDIO bus![%s] (%d)\n", mii->id,= rc); + return ERR_PTR(rc); + } + + return mii; +} +EXPORT_SYMBOL_GPL(devm_mdio_regmap_register); + +MODULE_DESCRIPTION("MDIO API over regmap"); +MODULE_AUTHOR("Maxime Chevallier "); +MODULE_LICENSE("GPL"); diff --git a/include/linux/mdio/mdio-regmap.h b/include/linux/mdio/mdio-reg= map.h new file mode 100644 index 000000000000..679d9069846b --- /dev/null +++ b/include/linux/mdio/mdio-regmap.h @@ -0,0 +1,26 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Driver for MMIO-Mapped MDIO devices. Some IPs expose internal PHYs or P= CS + * within the MMIO-mapped area + * + * Copyright (C) 2023 Maxime Chevallier + */ +#ifndef MDIO_REGMAP_H +#define MDIO_REGMAP_H + +#include + +struct device; +struct regmap; + +struct mdio_regmap_config { + struct device *parent; + struct regmap *regmap; + char name[MII_BUS_ID_SIZE]; + u8 valid_addr; + bool autoscan; +}; + +struct mii_bus *devm_mdio_regmap_register(struct device *dev, + const struct mdio_regmap_config *config); + +#endif --=20 2.40.1