From patchwork Wed May 3 12:10:16 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bharat Bhushan X-Patchwork-Id: 13230130 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 53029C77B75 for ; Wed, 3 May 2023 12:10:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229713AbjECMKv (ORCPT ); Wed, 3 May 2023 08:10:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34768 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229914AbjECMKu (ORCPT ); Wed, 3 May 2023 08:10:50 -0400 Received: from mx0b-0016f401.pphosted.com (mx0a-0016f401.pphosted.com [67.231.148.174]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 31B2359FE; Wed, 3 May 2023 05:10:46 -0700 (PDT) Received: from pps.filterd (m0045849.ppops.net [127.0.0.1]) by mx0a-0016f401.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 343A6a6r025611; Wed, 3 May 2023 05:10:31 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=marvell.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-type; s=pfpt0220; bh=x8Ty+WARYIjZ5C1uaJHgM7Vt35QzRKvyRhyTi8dyZTQ=; b=PDTW5RLvCU3k1R6KGAH5fKgyakxh1GSZzCdac2vRCq2SYUPqVtrpm3H9Kub+whPY5+5m FrRhMKOT9UjY4hk2qt1BusYD6T+mXcuKas1f8CqjGELsm85m6GOObeZPDCqU2LZ37yWZ PXWNOPnc4VibBnCNsf3oJ4A4t9+xUt4u4hl6snJP54CjS76BSXaM8PHB4ncqq7XjMSxU TIUcHZJ4vQo1/z5GQMjaxTk/26TSjfe8we8pKJ+RH4zEFwTczoj2689TtM2JYUiLOz4/ FxhH94zAyemXKed+u4Nw8P6XTGEdr72Ty3hfA94sxWaQZfYoe3vlupLvUjzfZrCGYLg2 0A== Received: from dc5-exch01.marvell.com ([199.233.59.181]) by mx0a-0016f401.pphosted.com (PPS) with ESMTPS id 3qbnjn0bmk-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-SHA384 bits=256 verify=NOT); Wed, 03 May 2023 05:10:30 -0700 Received: from DC5-EXCH01.marvell.com (10.69.176.38) by DC5-EXCH01.marvell.com (10.69.176.38) with Microsoft SMTP Server (TLS) id 15.0.1497.48; Wed, 3 May 2023 05:10:29 -0700 Received: from bbhushan2.marvell.com (10.69.176.80) by DC5-EXCH01.marvell.com (10.69.176.38) with Microsoft SMTP Server id 15.0.1497.48 via Frontend Transport; Wed, 3 May 2023 05:10:26 -0700 From: Bharat Bhushan To: , , , , , CC: Bharat Bhushan Subject: [PATCH 2/2 v5] Watchdog: Add marvell GTI watchdog driver Date: Wed, 3 May 2023 17:40:16 +0530 Message-ID: <20230503121016.6093-2-bbhushan2@marvell.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20230503121016.6093-1-bbhushan2@marvell.com> References: <20230503121016.6093-1-bbhushan2@marvell.com> MIME-Version: 1.0 X-Proofpoint-ORIG-GUID: w4qOuqyroG31zl-jRojPhg2QJvjPNuJU X-Proofpoint-GUID: w4qOuqyroG31zl-jRojPhg2QJvjPNuJU X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.254,Aquarius:18.0.942,Hydra:6.0.573,FMLib:17.11.170.22 definitions=2023-05-03_08,2023-05-03_01,2023-02-09_01 Precedence: bulk List-ID: X-Mailing-List: linux-watchdog@vger.kernel.org This patch add support for Marvell GTI watchdog. Global timer unit (GTI) support hardware watchdog timer. Software programs watchdog timer to generate interrupt on first timeout, second timeout is configured to be ignored and system reboots on third timeout. Signed-off-by: Bharat Bhushan --- v5: - Get clock frequency from clocks/clock-name device tree property So removed arch_timer_get_cntfrq() and asm include arch_timer.h - Removed GTI_CWD_GLOBAL_WDOG_IDX, use wdt-timer-index device tree property for timer - Some other clean-up as per review comment drivers/watchdog/Kconfig | 11 + drivers/watchdog/Makefile | 1 + drivers/watchdog/marvell_gti_wdt.c | 326 +++++++++++++++++++++++++++++ 3 files changed, 338 insertions(+) create mode 100644 drivers/watchdog/marvell_gti_wdt.c diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index f0872970daf9..a96e7d7c0ad2 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -1779,6 +1779,17 @@ config OCTEON_WDT from the first interrupt, it is then only poked when the device is written. +config MARVELL_GTI_WDT + tristate "Marvell GTI Watchdog driver" + depends on ARCH_THUNDER || COMPILE_TEST + help + Marvell GTI hardware supports watchdog timer. First timeout + works as watchdog pretimeout and installed interrupt handler + will be called on first timeout. Hardware can generate interrupt + to SCP on second timeout but it is not enabled, So second + timeout is ignored. If device poke does not happen then system + will reboot on third timeout. + config BCM2835_WDT tristate "Broadcom BCM2835 hardware watchdog" depends on ARCH_BCM2835 || (OF && COMPILE_TEST) diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index 9cbf6580f16c..bd425408fcaa 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -98,6 +98,7 @@ obj-$(CONFIG_VISCONTI_WATCHDOG) += visconti_wdt.o obj-$(CONFIG_MSC313E_WATCHDOG) += msc313e_wdt.o obj-$(CONFIG_APPLE_WATCHDOG) += apple_wdt.o obj-$(CONFIG_SUNPLUS_WATCHDOG) += sunplus_wdt.o +obj-$(CONFIG_MARVELL_GTI_WDT) += marvell_gti_wdt.o # X86 (i386 + ia64 + x86_64) Architecture obj-$(CONFIG_ACQUIRE_WDT) += acquirewdt.o diff --git a/drivers/watchdog/marvell_gti_wdt.c b/drivers/watchdog/marvell_gti_wdt.c new file mode 100644 index 000000000000..d0a2e6374dfb --- /dev/null +++ b/drivers/watchdog/marvell_gti_wdt.c @@ -0,0 +1,326 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Marvell GTI Watchdog driver + * + * Copyright (C) 2023 Marvell. + */ + +#include +#include +#include +#include +#include +#include + +/* + * Hardware supports following mode of operation: + * 1) Interrupt Only: + * This will generate the interrupt to arm core whenever timeout happens. + * + * 2) Interrupt + del3t (Interrupt to firmware (SCP processor)). + * This will generate interrupt to arm core on 1st timeout happens + * This will generate interrupt to SCP processor on 2nd timeout happens + * + * 3) Interrupt + Interrupt to SCP processor (called delt3t) + reboot. + * This will generate interrupt to arm core on 1st timeout happens + * Will generate interrupt to SCP processor on 2nd timeout happens, + * if interrupt is configured. + * Reboot on 3rd timeout. + * + * Driver will use hardware in mode-3 above so that system can reboot in case + * a hardware hang. Also h/w is configured not to generate SCP interrupt, so + * effectively 2nd timeout is ignored within hardware. + * + * First timeout is effectively watchdog pretimeout. + */ + +/* GTI CWD Watchdog (GTI_CWD_WDOG) Register */ +#define GTI_CWD_WDOG(reg_offset) (0x8 * reg_offset) +#define GTI_CWD_WDOG_MODE_INT_DEL3T_RST 0x3 +#define GTI_CWD_WDOG_MODE_MASK GENMASK_ULL(1, 0) +#define GTI_CWD_WDOG_LEN_SHIFT 4 +#define GTI_CWD_WDOG_LEN_MASK GENMASK_ULL(19, 4) +#define GTI_CWD_WDOG_CNT_SHIFT 20 +#define GTI_CWD_WDOG_CNT_MASK GENMASK_ULL(43, 20) + +/* GTI CWD Watchdog Interrupt (GTI_CWD_INT) Register */ +#define GTI_CWD_INT 0x200 +#define GTI_CWD_INT_PENDING_STATUS(bit) (1 << bit) + +/* GTI CWD Watchdog Interrupt Enable Clear (GTI_CWD_INT_ENA_CLR) Register */ +#define GTI_CWD_INT_ENA_CLR 0x210 +#define GTI_CWD_INT_ENA_CLR_VAL(bit) (1 << bit) + +/* GTI CWD Watchdog Interrupt Enable Set (GTI_CWD_INT_ENA_SET) Register */ +#define GTI_CWD_INT_ENA_SET 0x218 +#define GTI_CWD_INT_ENA_SET_VAL(bit) (1 << bit) + +/* GTI CWD Watchdog Poke (GTI_CWD_POKE) Registers */ +#define GTI_CWD_POKE(reg_offset) (0x10000 + 0x8 * reg_offset) +#define GTI_CWD_POKE_VAL 1 + +struct gti_wdt_priv { + struct watchdog_device wdev; + void __iomem *base; + u32 clock_freq; + struct clk *sclk; + /* + * GTI hardware block supports total 64 timers, wdt_timer_idx + * used for timer to be used for system watchdog. + */ + u32 wdt_timer_idx; +}; + +static irqreturn_t gti_wdt_interrupt(int irq, void *data) +{ + struct watchdog_device *wdev = data; + struct gti_wdt_priv *priv = watchdog_get_drvdata(wdev); + + /* Clear Interrupt Pending Status */ + writeq(GTI_CWD_INT_PENDING_STATUS(priv->wdt_timer_idx), + priv->base + GTI_CWD_INT); + + watchdog_notify_pretimeout(wdev); + + return IRQ_HANDLED; +} + +static int gti_wdt_ping(struct watchdog_device *wdev) +{ + struct gti_wdt_priv *priv = watchdog_get_drvdata(wdev); + + writeq(GTI_CWD_POKE_VAL, + priv->base + GTI_CWD_POKE(priv->wdt_timer_idx)); + + return 0; +} + +static int gti_wdt_start(struct watchdog_device *wdev) +{ + struct gti_wdt_priv *priv = watchdog_get_drvdata(wdev); + u64 regval; + + if (!wdev->pretimeout) + return -EINVAL; + + set_bit(WDOG_HW_RUNNING, &wdev->status); + + /* Clear any pending interrupt */ + writeq(GTI_CWD_INT_PENDING_STATUS(priv->wdt_timer_idx), + priv->base + GTI_CWD_INT); + + /* Enable Interrupt */ + writeq(GTI_CWD_INT_ENA_SET_VAL(priv->wdt_timer_idx), + priv->base + GTI_CWD_INT_ENA_SET); + + /* Set (Interrupt + SCP interrupt (DEL3T) + core domain reset) Mode */ + regval = readq(priv->base + GTI_CWD_WDOG(priv->wdt_timer_idx)); + regval |= GTI_CWD_WDOG_MODE_INT_DEL3T_RST; + writeq(regval, priv->base + GTI_CWD_WDOG(priv->wdt_timer_idx)); + + return 0; +} + +static int gti_wdt_stop(struct watchdog_device *wdev) +{ + struct gti_wdt_priv *priv = watchdog_get_drvdata(wdev); + u64 regval; + + /* Disable Interrupt */ + writeq(GTI_CWD_INT_ENA_CLR_VAL(priv->wdt_timer_idx), + priv->base + GTI_CWD_INT_ENA_CLR); + + /* Set GTI_CWD_WDOG.Mode = 0 to stop the timer */ + regval = readq(priv->base + GTI_CWD_WDOG(priv->wdt_timer_idx)); + regval &= ~GTI_CWD_WDOG_MODE_MASK; + writeq(regval, priv->base + GTI_CWD_WDOG(priv->wdt_timer_idx)); + + return 0; +} + +static int gti_wdt_settimeout(struct watchdog_device *wdev, + unsigned int timeout) +{ + struct gti_wdt_priv *priv = watchdog_get_drvdata(wdev); + u64 timeout_wdog, regval; + + /* Update new timeout */ + wdev->timeout = timeout; + + /* Pretimeout is 1/3 of timeout */ + wdev->pretimeout = timeout / 3; + + /* Get clock cycles from pretimeout */ + timeout_wdog = (u64)priv->clock_freq * wdev->pretimeout; + + /* Watchdog counts in 1024 cycle steps */ + timeout_wdog = timeout_wdog >> 10; + + /* GTI_CWD_WDOG.CNT: reload counter is 16-bit */ + timeout_wdog = (timeout_wdog + 0xff) >> 8; + if (timeout_wdog >= 0x10000) + timeout_wdog = 0xffff; + + /* + * GTI_CWD_WDOG.LEN is 24bit, lower 8-bits should be zero and + * upper 16-bits are same as GTI_CWD_WDOG.CNT + */ + regval = readq(priv->base + GTI_CWD_WDOG(priv->wdt_timer_idx)); + regval &= GTI_CWD_WDOG_MODE_MASK; + regval |= (timeout_wdog << (GTI_CWD_WDOG_CNT_SHIFT + 8)) | + (timeout_wdog << GTI_CWD_WDOG_LEN_SHIFT); + writeq(regval, priv->base + GTI_CWD_WDOG(priv->wdt_timer_idx)); + + return 0; +} + +static int gti_wdt_set_pretimeout(struct watchdog_device *wdev, + unsigned int timeout) +{ + struct gti_wdt_priv *priv = watchdog_get_drvdata(wdev); + struct watchdog_device *wdog_dev = &priv->wdev; + + /* pretimeout should 1/3 of max_timeout */ + if (timeout * 3 <= wdog_dev->max_timeout) + return gti_wdt_settimeout(wdev, timeout * 3); + + return -EINVAL; +} + +static void gti_clk_disable_unprepare(void *data) +{ + clk_disable_unprepare(data); +} + +static int gti_wdt_get_cntfrq(struct platform_device *pdev, + struct gti_wdt_priv *priv) +{ + int err; + + priv->sclk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(priv->sclk)) + return PTR_ERR(priv->sclk); + + err = clk_prepare_enable(priv->sclk); + if (err) + return err; + + err = devm_add_action_or_reset(&pdev->dev, + gti_clk_disable_unprepare, priv->sclk); + if (err) + return err; + + priv->clock_freq = clk_get_rate(priv->sclk); + if (!priv->clock_freq) + return -EINVAL; + + return 0; +} + +static const struct watchdog_info gti_wdt_ident = { + .identity = "Marvell GTI watchdog", + .options = WDIOF_SETTIMEOUT | WDIOF_PRETIMEOUT | WDIOF_KEEPALIVEPING | + WDIOF_MAGICCLOSE | WDIOF_CARDRESET, +}; + +static const struct watchdog_ops gti_wdt_ops = { + .owner = THIS_MODULE, + .start = gti_wdt_start, + .stop = gti_wdt_stop, + .ping = gti_wdt_ping, + .set_timeout = gti_wdt_settimeout, + .set_pretimeout = gti_wdt_set_pretimeout, +}; + +static int gti_wdt_probe(struct platform_device *pdev) +{ + struct gti_wdt_priv *priv; + struct device *dev = &pdev->dev; + struct watchdog_device *wdog_dev; + u64 max_pretimeout; + u32 wdt_idx; + int irq; + int err; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->base)) + return dev_err_probe(&pdev->dev, PTR_ERR(priv->base), + "reg property not valid/found\n"); + + err = gti_wdt_get_cntfrq(pdev, priv); + if (err) + return dev_err_probe(&pdev->dev, err, + "GTI clock frequency not valid/found"); + + /* + * GTI hardware block supports total 64 timers, "wdt-timer-index" + * property used for timer to be used for system watchdog. + */ + err = of_property_read_u32(dev->of_node, "wdt-timer-index", &wdt_idx); + if (err || wdt_idx > 63) + return dev_err_probe(&pdev->dev, err, + "GTI wdog timer index not valid/found"); + + priv->wdt_timer_idx = wdt_idx; + wdog_dev = &priv->wdev; + wdog_dev->info = >i_wdt_ident, + wdog_dev->ops = >i_wdt_ops, + wdog_dev->parent = dev; + /* + * Watchdog counter is 24 bit where lower 8 bits are zeros + * This counter decrements every 1024 clock cycles. + */ + max_pretimeout = (GTI_CWD_WDOG_CNT_MASK >> GTI_CWD_WDOG_CNT_SHIFT); + max_pretimeout &= ~0xFFUL; + max_pretimeout = (max_pretimeout * 1024) / priv->clock_freq; + wdog_dev->pretimeout = max_pretimeout; + + /* Maximum timeout is 3 times the pretimeout */ + wdog_dev->max_timeout = max_pretimeout * 3; + /* Minimum first timeout (pretimeout) is 1, so min_timeout as 3 */ + wdog_dev->min_timeout = 3; + wdog_dev->timeout = wdog_dev->pretimeout; + + watchdog_set_drvdata(wdog_dev, priv); + platform_set_drvdata(pdev, priv); + gti_wdt_settimeout(wdog_dev, wdog_dev->timeout); + watchdog_stop_on_reboot(wdog_dev); + watchdog_stop_on_unregister(wdog_dev); + + err = devm_watchdog_register_device(dev, wdog_dev); + if (err) + return err; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return dev_err_probe(&pdev->dev, irq, "IRQ resource not found\n"); + + err = devm_request_irq(dev, irq, gti_wdt_interrupt, 0, + pdev->name, &priv->wdev); + if (err) + return dev_err_probe(dev, err, "Failed to register interrupt handler\n"); + + dev_info(dev, "Watchdog enabled (timeout=%d sec)\n", wdog_dev->timeout); + return 0; +} + +static const struct of_device_id gti_wdt_of_match[] = { + { .compatible = "marvell,gti-wdt", }, + { }, +}; +MODULE_DEVICE_TABLE(of, gti_wdt_of_match); + +static struct platform_driver gti_wdt_driver = { + .driver = { + .name = "gti-wdt", + .of_match_table = gti_wdt_of_match, + }, + .probe = gti_wdt_probe, +}; +module_platform_driver(gti_wdt_driver); + +MODULE_AUTHOR("Bharat Bhushan "); +MODULE_DESCRIPTION("Marvell GTI watchdog driver");