From patchwork Wed Dec 6 23:46:09 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Halaney X-Patchwork-Id: 13482378 X-Patchwork-Delegate: kuba@kernel.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="gTZVBEzA" Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0D2A5C6 for ; Wed, 6 Dec 2023 15:46:20 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1701906380; 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; bh=8esKVkgkdO38qfOOlPF2GDuWhXzWAxbw0J892C+UC7Y=; b=gTZVBEzA7eNmgI4iUx3i5yXgZYBlR6AQa1CCVSAJX1XXwQMTnhFHngolz8mg7rKv2G28pL /hCPLquzeSMY7fCeeTJcjtlGcZSVi0KopQxWyoMaWZEHMC6W/cv1WRwQotvn25Bxk2Fz/Y OcBRm9ADIU2MULWQwKQ6BBZ8fsYxG6E= Received: from mail-oo1-f72.google.com (mail-oo1-f72.google.com [209.85.161.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-486-cuYXFI89M5u8OuoNXZKV5A-1; Wed, 06 Dec 2023 18:46:18 -0500 X-MC-Unique: cuYXFI89M5u8OuoNXZKV5A-1 Received: by mail-oo1-f72.google.com with SMTP id 006d021491bc7-58d53348a03so88019eaf.2 for ; Wed, 06 Dec 2023 15:46:18 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1701906378; x=1702511178; h=cc:to:message-id:content-transfer-encoding:mime-version:subject :date:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=8esKVkgkdO38qfOOlPF2GDuWhXzWAxbw0J892C+UC7Y=; b=OPmSqKSvwyIOxyYDdO3JSTLOI7uoS51kBr+CggELbNMWjBujXzWxeboSJMum9iP3V0 MxdvRdQwb6x+rOeMB2CJU/pQpI73l/S70BfAcTz+4o9suvbJ3rU6gWOQPceXUlChpoRV A4NFd8vbvGmbPhB0dWnSNZMYGdT81sR96pon3SJdV7oM3fq0QgRRJOOmaMja+FYHLRXs mWI4XM3w4kO94WAYSaUmcsed3TtYnrZCuj+CXRePcqXhyF0iSMv8vJ87u7Giyp8gYH9K F75MFB7MAu5+TxcguKyHeESYBkUBysgvPHctFSnlMM5cmupCZLsaHMxQy08VrDDiuwAC Sc1g== X-Gm-Message-State: AOJu0YzXNgXPQSQTzceMJaNO4iUcUu25TCvGA5bJwSKp1TPCQygJxHn4 doVXd+CbdVEYWX14uSuRiTB2W+xmxQWNx1UciGKlh5X1R25vMQ9VeslBy3pXOYQ84r1lSXwTGpk lQb1TKvc8V8IjQl2w X-Received: by 2002:a05:6358:2910:b0:16d:bbb3:69c6 with SMTP id y16-20020a056358291000b0016dbbb369c6mr2398877rwb.13.1701906377931; Wed, 06 Dec 2023 15:46:17 -0800 (PST) X-Google-Smtp-Source: AGHT+IEAsIygwOoQKZlum7cq8klqlJozHBJy1wvtOxVzB6Tfsb98hdv5DwTkASEhC5ZBOAlTAOdQBA== X-Received: by 2002:a05:6358:2910:b0:16d:bbb3:69c6 with SMTP id y16-20020a056358291000b0016dbbb369c6mr2398863rwb.13.1701906377591; Wed, 06 Dec 2023 15:46:17 -0800 (PST) Received: from [192.168.1.164] ([2600:1700:1ff0:d0e0::47]) by smtp.gmail.com with ESMTPSA id lg21-20020a056214549500b0067a14238fa9sm11568qvb.94.2023.12.06.15.46.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 06 Dec 2023 15:46:17 -0800 (PST) From: Andrew Halaney Date: Wed, 06 Dec 2023 17:46:09 -0600 Subject: [PATCH net-next v2] net: stmmac: don't create a MDIO bus if unnecessary Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20231206-stmmac-no-mdio-node-v2-1-333cae49b1ca@redhat.com> X-B4-Tracking: v=1; b=H4sIAMAHcWUC/z2MwQqDMBBEf0X23BU31lY99T9KD9FdNWASSYII4 r839NDTzGOYd0KUYCRCX5wQZDfReJdB3QoYF+1mQcOZQVWqJlJPjMlaPaLzaNn4nCxIPHSsW60 a7iA/tyCTOX7WNzhJ6ORI8MnLFLzFtATRf2vVVi3l0txLokdTI+EQ5vU1zCx7ua1wXV/b0uTPp gAAAA== To: Alexandre Torgue , Jose Abreu , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Maxime Coquelin Cc: netdev@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Bartosz Golaszewski , Andrew Halaney X-Mailer: b4 0.12.3 X-Patchwork-Delegate: kuba@kernel.org The stmmac_dt_phy() function, which parses the devicetree node of the MAC and ultimately causes MDIO bus allocation, misinterprets what fixed-link means in relation to the MAC's MDIO bus. This results in a MDIO bus being created in situations it need not be. Currently a MDIO bus is created if the description is either: 1. Not fixed-link 2. fixed-link but contains a MDIO bus as well The "1" case above isn't always accurate. If there's a phy-handle, it could be referencing a phy on another MDIO controller's bus[1]. In this case currently the MAC will make a MDIO bus and scan it all anyways unnecessarily. There's also a lot of upstream devicetrees[2] that expect a MDIO bus to be created and scanned for a phy. This case can also be inferred from the platform description by not having a phy-handle && not being fixed-link. This hits case "1" in the current driver's logic. Let's improve the logic to create a MDIO bus if either: - Devicetree contains a MDIO bus - !fixed-link && !phy-handle (legacy handling) Below upstream devicetree snippets can be found that explain some of the cases above more concretely. Here's[0] a devicetree example where the MAC is both fixed-link and driving a switch on MDIO (case "2" above). This needs a MDIO bus to be created: &fec1 { phy-mode = "rmii"; fixed-link { speed = <100>; full-duplex; }; mdio1: mdio { switch0: switch0@0 { compatible = "marvell,mv88e6190"; pinctrl-0 = <&pinctrl_gpio_switch0>; }; }; }; Here's[1] an example where there is no MDIO bus or fixed-link for the ethernet1 MAC, so no MDIO bus should be created since ethernet0 is the MDIO master for ethernet1's phy: ðernet0 { phy-mode = "sgmii"; phy-handle = <&sgmii_phy0>; mdio { compatible = "snps,dwmac-mdio"; sgmii_phy0: phy@8 { compatible = "ethernet-phy-id0141.0dd4"; reg = <0x8>; device_type = "ethernet-phy"; }; sgmii_phy1: phy@a { compatible = "ethernet-phy-id0141.0dd4"; reg = <0xa>; device_type = "ethernet-phy"; }; }; }; ðernet1 { phy-mode = "sgmii"; phy-handle = <&sgmii_phy1>; }; Finally there's descriptions like this[2] which don't describe the MDIO bus but expect it to be created and the whole address space scanned for a phy since there's no phy-handle or fixed-link described: &gmac { phy-supply = <&vcc_lan>; phy-mode = "rmii"; snps,reset-gpio = <&gpio3 RK_PB4 GPIO_ACTIVE_HIGH>; snps,reset-active-low; snps,reset-delays-us = <0 10000 1000000>; }; [0] https://elixir.bootlin.com/linux/v6.5-rc5/source/arch/arm/boot/dts/nxp/vf/vf610-zii-ssmb-dtu.dts [1] https://elixir.bootlin.com/linux/v6.6-rc5/source/arch/arm64/boot/dts/qcom/sa8775p-ride.dts [2] https://elixir.bootlin.com/linux/v6.6-rc5/source/arch/arm64/boot/dts/rockchip/rk3368-r88.dts#L164 Co-developed-by: Bartosz Golaszewski Signed-off-by: Bartosz Golaszewski Signed-off-by: Andrew Halaney --- .../net/ethernet/stmicro/stmmac/stmmac_platform.c | 85 ++++++++++------------ 1 file changed, 37 insertions(+), 48 deletions(-) --- base-commit: fd8a79b63710acb84321be3ce74be23c876873fb change-id: 20231127-stmmac-no-mdio-node-1db9da8a25d9 Best regards, diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c index 1ffde555da47..7da461fe93f6 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c @@ -296,69 +296,39 @@ static int stmmac_mtl_setup(struct platform_device *pdev, } /** - * stmmac_dt_phy - parse device-tree driver parameters to allocate PHY resources - * @plat: driver data platform structure - * @np: device tree node - * @dev: device pointer - * Description: - * The mdio bus will be allocated in case of a phy transceiver is on board; - * it will be NULL if the fixed-link is configured. - * If there is the "snps,dwmac-mdio" sub-node the mdio will be allocated - * in any case (for DSA, mdio must be registered even if fixed-link). - * The table below sums the supported configurations: - * ------------------------------- - * snps,phy-addr | Y - * ------------------------------- - * phy-handle | Y - * ------------------------------- - * fixed-link | N - * ------------------------------- - * snps,dwmac-mdio | - * even if | Y - * fixed-link | - * ------------------------------- + * stmmac_of_get_mdio() - Gets the MDIO bus from the devicetree + * @np: devicetree node * - * It returns 0 in case of success otherwise -ENODEV. + * The MDIO bus will be searched for in the following ways: + * 1. The compatible is "snps,dwc-qos-ethernet-4.10" && a "mdio" named + * child node exists + * 2. A child node with the "snps,dwmac-mdio" compatible is present + * + * Return: The MDIO node if present otherwise NULL */ -static int stmmac_dt_phy(struct plat_stmmacenet_data *plat, - struct device_node *np, struct device *dev) +static struct device_node *stmmac_of_get_mdio(struct device_node *np) { - bool mdio = !of_phy_is_fixed_link(np); static const struct of_device_id need_mdio_ids[] = { { .compatible = "snps,dwc-qos-ethernet-4.10" }, {}, }; + struct device_node *mdio_node = NULL; if (of_match_node(need_mdio_ids, np)) { - plat->mdio_node = of_get_child_by_name(np, "mdio"); + mdio_node = of_get_child_by_name(np, "mdio"); } else { /** * If snps,dwmac-mdio is passed from DT, always register * the MDIO */ - for_each_child_of_node(np, plat->mdio_node) { - if (of_device_is_compatible(plat->mdio_node, + for_each_child_of_node(np, mdio_node) { + if (of_device_is_compatible(mdio_node, "snps,dwmac-mdio")) break; } } - if (plat->mdio_node) { - dev_dbg(dev, "Found MDIO subnode\n"); - mdio = true; - } - - if (mdio) { - plat->mdio_bus_data = - devm_kzalloc(dev, sizeof(struct stmmac_mdio_bus_data), - GFP_KERNEL); - if (!plat->mdio_bus_data) - return -ENOMEM; - - plat->mdio_bus_data->needs_reset = true; - } - - return 0; + return mdio_node; } /** @@ -417,6 +387,7 @@ stmmac_probe_config_dt(struct platform_device *pdev, u8 *mac) struct device_node *np = pdev->dev.of_node; struct plat_stmmacenet_data *plat; struct stmmac_dma_cfg *dma_cfg; + bool legacy_mdio; int phy_mode; void *ret; int rc; @@ -471,10 +442,28 @@ stmmac_probe_config_dt(struct platform_device *pdev, u8 *mac) if (of_property_read_u32(np, "snps,phy-addr", &plat->phy_addr) == 0) dev_warn(&pdev->dev, "snps,phy-addr property is deprecated\n"); - /* To Configure PHY by using all device-tree supported properties */ - rc = stmmac_dt_phy(plat, np, &pdev->dev); - if (rc) - return ERR_PTR(rc); + plat->mdio_node = stmmac_of_get_mdio(np); + if (plat->mdio_node) + dev_dbg(&pdev->dev, "Found MDIO subnode\n"); + + /* Legacy devicetrees allowed for no MDIO bus description and expect + * the bus to be scanned for devices. If there's no phy or fixed-link + * described assume this is the case since there must be something + * connected to the MAC. + */ + legacy_mdio = !of_phy_is_fixed_link(np) && !plat->phy_node; + if (legacy_mdio) + dev_info(&pdev->dev, "Deprecated MDIO bus assumption used\n"); + + if (plat->mdio_node || legacy_mdio) { + plat->mdio_bus_data = devm_kzalloc(&pdev->dev, + sizeof(struct stmmac_mdio_bus_data), + GFP_KERNEL); + if (!plat->mdio_bus_data) + return ERR_PTR(-ENOMEM); + + plat->mdio_bus_data->needs_reset = true; + } of_property_read_u32(np, "tx-fifo-depth", &plat->tx_fifo_size);