From patchwork Wed Aug 17 09:44:06 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ravi Gunasekaran X-Patchwork-Id: 12945660 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 7D9C8C25B08 for ; Wed, 17 Aug 2022 09:45:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232435AbiHQJpv (ORCPT ); Wed, 17 Aug 2022 05:45:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59006 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230402AbiHQJpr (ORCPT ); Wed, 17 Aug 2022 05:45:47 -0400 Received: from lelv0142.ext.ti.com (lelv0142.ext.ti.com [198.47.23.249]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6B54A69F49; Wed, 17 Aug 2022 02:45:46 -0700 (PDT) Received: from lelv0265.itg.ti.com ([10.180.67.224]) by lelv0142.ext.ti.com (8.15.2/8.15.2) with ESMTP id 27H9jLvq110379; Wed, 17 Aug 2022 04:45:21 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1660729521; bh=HGpq7tVVTWlwZ0ZMf6FNPsqizH4eSWDVet6S21Oyjbw=; h=From:To:CC:Subject:Date; b=jbfV0QrIvWjLpSTo6J2oEfMn5J5H8LyEpDzDEophyeljRkVyq9sabSL+VP9qDU5cA ryXgnlfL4AW1Es/fRB/I8S3/ThEZPSMl+UsnWdkmDfRiGJO09EBw6JgVJ2A00cLe5n l3c15xYQVe3Bbh3hrrmlkG4dAnJQukFUPT43ANus= Received: from DLEE103.ent.ti.com (dlee103.ent.ti.com [157.170.170.33]) by lelv0265.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 27H9jLud012584 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Wed, 17 Aug 2022 04:45:21 -0500 Received: from DLEE104.ent.ti.com (157.170.170.34) by DLEE103.ent.ti.com (157.170.170.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.6; Wed, 17 Aug 2022 04:45:21 -0500 Received: from lelv0326.itg.ti.com (10.180.67.84) by DLEE104.ent.ti.com (157.170.170.34) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.6 via Frontend Transport; Wed, 17 Aug 2022 04:45:20 -0500 Received: from uda0500640.dal.design.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by lelv0326.itg.ti.com (8.15.2/8.15.2) with ESMTP id 27H9jG4f027302; Wed, 17 Aug 2022 04:45:17 -0500 From: Ravi Gunasekaran To: CC: , , , , , , , , , , Subject: [PATCH v3 net-next] net: ethernet: ti: davinci_mdio: Add workaround for errata i2329 Date: Wed, 17 Aug 2022 15:14:06 +0530 Message-ID: <20220817094406.10658-1-r-gunasekaran@ti.com> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org On the CPSW and ICSS peripherals, there is a possibility that the MDIO interface returns corrupt data on MDIO reads or writes incorrect data on MDIO writes. There is also a possibility for the MDIO interface to become unavailable until the next peripheral reset. The workaround is to configure the MDIO in manual mode and disable the MDIO state machine and emulate the MDIO protocol by reading and writing appropriate fields in MDIO_MANUAL_IF_REG register of the MDIO controller to manipulate the MDIO clock and data pins. More details about the errata i2329 and the workaround is available in: https://www.ti.com/lit/er/sprz487a/sprz487a.pdf Add implementation to disable MDIO state machine, configure MDIO in manual mode and achieve MDIO read and writes via MDIO Bitbanging Signed-off-by: Ravi Gunasekaran Reported-by: kernel test robot Reviewed-by: Andrew Lunn --- Changelog: v2 -> v3: 1. Remove PHY ID and register validation check 2. Fix the compile error reported by kernel test robot v1 -> v2: 1. Use the existing MDIO bitbang framework v1: https://lore.kernel.org/netdev/20220808111229.11951-1-r-gunasekaran@ti.com/ v2: https://lore.kernel.org/netdev/20220810111345.31200-1-r-gunasekaran@ti.com/ drivers/net/ethernet/ti/davinci_mdio.c | 242 +++++++++++++++++++++++-- 1 file changed, 231 insertions(+), 11 deletions(-) diff --git a/drivers/net/ethernet/ti/davinci_mdio.c b/drivers/net/ethernet/ti/davinci_mdio.c index ea3772618043..946b9753ccfb 100644 --- a/drivers/net/ethernet/ti/davinci_mdio.c +++ b/drivers/net/ethernet/ti/davinci_mdio.c @@ -26,6 +26,8 @@ #include #include #include +#include +#include /* * This timeout definition is a worst-case ultra defensive measure against @@ -41,6 +43,7 @@ struct davinci_mdio_of_param { int autosuspend_delay_ms; + bool manual_mode; }; struct davinci_mdio_regs { @@ -49,6 +52,15 @@ struct davinci_mdio_regs { #define CONTROL_IDLE BIT(31) #define CONTROL_ENABLE BIT(30) #define CONTROL_MAX_DIV (0xffff) +#define CONTROL_CLKDIV GENMASK(15, 0) + +#define MDIO_MAN_MDCLK_O BIT(2) +#define MDIO_MAN_OE BIT(1) +#define MDIO_MAN_PIN BIT(0) +#define MDIO_MANUALMODE BIT(31) + +#define MDIO_PIN 0 + u32 alive; u32 link; @@ -59,7 +71,9 @@ struct davinci_mdio_regs { u32 userintmasked; u32 userintmaskset; u32 userintmaskclr; - u32 __reserved_1[20]; + u32 manualif; + u32 poll; + u32 __reserved_1[18]; struct { u32 access; @@ -79,6 +93,7 @@ static const struct mdio_platform_data default_pdata = { struct davinci_mdio_data { struct mdio_platform_data pdata; + struct mdiobb_ctrl bb_ctrl; struct davinci_mdio_regs __iomem *regs; struct clk *clk; struct device *dev; @@ -90,6 +105,7 @@ struct davinci_mdio_data { */ bool skip_scan; u32 clk_div; + bool manual_mode; }; static void davinci_mdio_init_clk(struct davinci_mdio_data *data) @@ -128,9 +144,122 @@ static void davinci_mdio_enable(struct davinci_mdio_data *data) writel(data->clk_div | CONTROL_ENABLE, &data->regs->control); } -static int davinci_mdio_reset(struct mii_bus *bus) +static void davinci_mdio_disable(struct davinci_mdio_data *data) +{ + u32 reg; + + /* Disable MDIO state machine */ + reg = readl(&data->regs->control); + + reg &= ~CONTROL_CLKDIV; + reg |= data->clk_div; + + reg &= ~CONTROL_ENABLE; + writel(reg, &data->regs->control); +} + +static void davinci_mdio_enable_manual_mode(struct davinci_mdio_data *data) +{ + u32 reg; + /* set manual mode */ + reg = readl(&data->regs->poll); + reg |= MDIO_MANUALMODE; + writel(reg, &data->regs->poll); +} + +static void davinci_set_mdc(struct mdiobb_ctrl *ctrl, int level) +{ + struct davinci_mdio_data *data; + u32 reg; + + data = container_of(ctrl, struct davinci_mdio_data, bb_ctrl); + reg = readl(&data->regs->manualif); + + if (level) + reg |= MDIO_MAN_MDCLK_O; + else + reg &= ~MDIO_MAN_MDCLK_O; + + writel(reg, &data->regs->manualif); +} + +static void davinci_set_mdio_dir(struct mdiobb_ctrl *ctrl, int output) +{ + struct davinci_mdio_data *data; + u32 reg; + + data = container_of(ctrl, struct davinci_mdio_data, bb_ctrl); + reg = readl(&data->regs->manualif); + + if (output) + reg |= MDIO_MAN_OE; + else + reg &= ~MDIO_MAN_OE; + + writel(reg, &data->regs->manualif); +} + +static void davinci_set_mdio_data(struct mdiobb_ctrl *ctrl, int value) +{ + struct davinci_mdio_data *data; + u32 reg; + + data = container_of(ctrl, struct davinci_mdio_data, bb_ctrl); + reg = readl(&data->regs->manualif); + + if (value) + reg |= MDIO_MAN_PIN; + else + reg &= ~MDIO_MAN_PIN; + + writel(reg, &data->regs->manualif); +} + +static int davinci_get_mdio_data(struct mdiobb_ctrl *ctrl) +{ + struct davinci_mdio_data *data; + unsigned long reg; + + data = container_of(ctrl, struct davinci_mdio_data, bb_ctrl); + reg = readl(&data->regs->manualif); + return test_bit(MDIO_PIN, ®); +} + +static int davinci_mdiobb_read(struct mii_bus *bus, int phy, int reg) +{ + int ret; + + ret = pm_runtime_resume_and_get(bus->parent); + if (ret < 0) + return ret; + + ret = mdiobb_read(bus, phy, reg); + + pm_runtime_mark_last_busy(bus->parent); + pm_runtime_put_autosuspend(bus->parent); + + return ret; +} + +static int davinci_mdiobb_write(struct mii_bus *bus, int phy, int reg, + u16 val) +{ + int ret; + + ret = pm_runtime_resume_and_get(bus->parent); + if (ret < 0) + return ret; + + ret = mdiobb_write(bus, phy, reg, val); + + pm_runtime_mark_last_busy(bus->parent); + pm_runtime_put_autosuspend(bus->parent); + + return ret; +} + +static int davinci_mdio_common_reset(struct davinci_mdio_data *data) { - struct davinci_mdio_data *data = bus->priv; u32 phy_mask, ver; int ret; @@ -138,6 +267,11 @@ static int davinci_mdio_reset(struct mii_bus *bus) if (ret < 0) return ret; + if (data->manual_mode) { + davinci_mdio_disable(data); + davinci_mdio_enable_manual_mode(data); + } + /* wait for scan logic to settle */ msleep(PHY_MAX_ADDR * data->access_time); @@ -171,6 +305,23 @@ static int davinci_mdio_reset(struct mii_bus *bus) return 0; } +static int davinci_mdio_reset(struct mii_bus *bus) +{ + struct davinci_mdio_data *data = bus->priv; + + return davinci_mdio_common_reset(data); +} + +static int davinci_mdiobb_reset(struct mii_bus *bus) +{ + struct mdiobb_ctrl *ctrl = bus->priv; + struct davinci_mdio_data *data; + + data = container_of(ctrl, struct davinci_mdio_data, bb_ctrl); + + return davinci_mdio_common_reset(data); +} + /* wait until hardware is ready for another user access */ static inline int wait_for_user_access(struct davinci_mdio_data *data) { @@ -318,6 +469,28 @@ static int davinci_mdio_probe_dt(struct mdio_platform_data *data, return 0; } +struct k3_mdio_soc_data { + bool manual_mode; +}; + +static const struct k3_mdio_soc_data am65_mdio_soc_data = { + .manual_mode = true, +}; + +static const struct soc_device_attribute k3_mdio_socinfo[] = { + { .family = "AM62X", .revision = "SR1.0", .data = &am65_mdio_soc_data }, + { .family = "AM64X", .revision = "SR1.0", .data = &am65_mdio_soc_data }, + { .family = "AM64X", .revision = "SR2.0", .data = &am65_mdio_soc_data }, + { .family = "AM65X", .revision = "SR1.0", .data = &am65_mdio_soc_data }, + { .family = "AM65X", .revision = "SR2.0", .data = &am65_mdio_soc_data }, + { .family = "J7200", .revision = "SR1.0", .data = &am65_mdio_soc_data }, + { .family = "J7200", .revision = "SR2.0", .data = &am65_mdio_soc_data }, + { .family = "J721E", .revision = "SR1.0", .data = &am65_mdio_soc_data }, + { .family = "J721E", .revision = "SR2.0", .data = &am65_mdio_soc_data }, + { .family = "J721S2", .revision = "SR1.0", .data = &am65_mdio_soc_data}, + { /* sentinel */ }, +}; + #if IS_ENABLED(CONFIG_OF) static const struct davinci_mdio_of_param of_cpsw_mdio_data = { .autosuspend_delay_ms = 100, @@ -331,6 +504,14 @@ static const struct of_device_id davinci_mdio_of_mtable[] = { MODULE_DEVICE_TABLE(of, davinci_mdio_of_mtable); #endif +static const struct mdiobb_ops davinci_mdiobb_ops = { + .owner = THIS_MODULE, + .set_mdc = davinci_set_mdc, + .set_mdio_dir = davinci_set_mdio_dir, + .set_mdio_data = davinci_set_mdio_data, + .get_mdio_data = davinci_get_mdio_data, +}; + static int davinci_mdio_probe(struct platform_device *pdev) { struct mdio_platform_data *pdata = dev_get_platdata(&pdev->dev); @@ -345,7 +526,26 @@ static int davinci_mdio_probe(struct platform_device *pdev) if (!data) return -ENOMEM; - data->bus = devm_mdiobus_alloc(dev); + data->manual_mode = false; + data->bb_ctrl.ops = &davinci_mdiobb_ops; + + if (IS_ENABLED(CONFIG_OF) && dev->of_node) { + const struct soc_device_attribute *soc_match_data; + + soc_match_data = soc_device_match(k3_mdio_socinfo); + if (soc_match_data && soc_match_data->data) { + const struct k3_mdio_soc_data *socdata = + soc_match_data->data; + + data->manual_mode = socdata->manual_mode; + } + } + + if (data->manual_mode) + data->bus = alloc_mdio_bitbang(&data->bb_ctrl); + else + data->bus = devm_mdiobus_alloc(dev); + if (!data->bus) { dev_err(dev, "failed to alloc mii bus\n"); return -ENOMEM; @@ -371,11 +571,20 @@ static int davinci_mdio_probe(struct platform_device *pdev) } data->bus->name = dev_name(dev); - data->bus->read = davinci_mdio_read; - data->bus->write = davinci_mdio_write; - data->bus->reset = davinci_mdio_reset; + + if (data->manual_mode) { + data->bus->read = davinci_mdiobb_read; + data->bus->write = davinci_mdiobb_write; + data->bus->reset = davinci_mdiobb_reset; + + dev_info(dev, "Configuring MDIO in manual mode\n"); + } else { + data->bus->read = davinci_mdio_read; + data->bus->write = davinci_mdio_write; + data->bus->reset = davinci_mdio_reset; + data->bus->priv = data; + } data->bus->parent = dev; - data->bus->priv = data; data->clk = devm_clk_get(dev, "fck"); if (IS_ERR(data->clk)) { @@ -433,9 +642,13 @@ static int davinci_mdio_remove(struct platform_device *pdev) { struct davinci_mdio_data *data = platform_get_drvdata(pdev); - if (data->bus) + if (data->bus) { mdiobus_unregister(data->bus); + if (data->manual_mode) + free_mdio_bitbang(data->bus); + } + pm_runtime_dont_use_autosuspend(&pdev->dev); pm_runtime_disable(&pdev->dev); @@ -452,7 +665,9 @@ static int davinci_mdio_runtime_suspend(struct device *dev) ctrl = readl(&data->regs->control); ctrl &= ~CONTROL_ENABLE; writel(ctrl, &data->regs->control); - wait_for_idle(data); + + if (!data->manual_mode) + wait_for_idle(data); return 0; } @@ -461,7 +676,12 @@ static int davinci_mdio_runtime_resume(struct device *dev) { struct davinci_mdio_data *data = dev_get_drvdata(dev); - davinci_mdio_enable(data); + if (data->manual_mode) { + davinci_mdio_disable(data); + davinci_mdio_enable_manual_mode(data); + } else { + davinci_mdio_enable(data); + } return 0; } #endif