From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755573AbaDKUuO (ORCPT ); Fri, 11 Apr 2014 16:50:14 -0400 Received: from mga02.intel.com ([134.134.136.20]:25642 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755485AbaDKUuK (ORCPT ); Fri, 11 Apr 2014 16:50:10 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.97,843,1389772800"; d="scan'208";a="491550252" From: David Cohen To: wim@iguana.be, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, x86@kernel.org Cc: linux-kernel@vger.kernel.org, linux-watchdog@vger.kernel.org, gnomes@lxorguk.ukuu.org.uk, david.a.cohen@linux.intel.com, Eric Ernst Subject: [PATCH v2 1/2] watchdog: add Intel MID watchdog driver support Date: Fri, 11 Apr 2014 13:50:06 -0700 Message-Id: <1397249407-5417-2-git-send-email-david.a.cohen@linux.intel.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1397249407-5417-1-git-send-email-david.a.cohen@linux.intel.com> References: <1396990744-10695-1-git-send-email-david.a.cohen@linux.intel.com> <1397249407-5417-1-git-send-email-david.a.cohen@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add initial Intel MID watchdog driver support. This driver is an initial implementation of generic Intel MID watchdog driver. Currently it supports Intel Merrifield platform. Signed-off-by: Eric Ernst Signed-off-by: David Cohen --- drivers/watchdog/Kconfig | 13 +++ drivers/watchdog/Makefile | 1 + drivers/watchdog/intel-mid_wdt.c | 209 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 223 insertions(+) create mode 100644 drivers/watchdog/intel-mid_wdt.c diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 79d25894343a..0e110c37aa5c 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -643,6 +643,19 @@ config INTEL_SCU_WATCHDOG To compile this driver as a module, choose M here. +config INTEL_MID_WATCHDOG + tristate "Intel MID Watchdog Timer" + depends on X86_INTEL_MID + select WATCHDOG_CORE + ---help--- + Watchdog timer driver built into the Intel SCU for Intel MID + Platforms. + + This driver currently supports only the watchdog evolution + implementation in SCU, available for Merrifield generation. + + To compile this driver as a module, choose M here. + config ITCO_WDT tristate "Intel TCO Timer/Watchdog" depends on (X86 || IA64) && PCI diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index 985a66cda76f..b927e7496eb4 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -113,6 +113,7 @@ obj-$(CONFIG_W83977F_WDT) += w83977f_wdt.o obj-$(CONFIG_MACHZ_WDT) += machzwd.o obj-$(CONFIG_SBC_EPX_C3_WATCHDOG) += sbc_epx_c3.o obj-$(CONFIG_INTEL_SCU_WATCHDOG) += intel_scu_watchdog.o +obj-$(CONFIG_INTEL_MID_WATCHDOG) += intel-mid_wdt.o # M32R Architecture diff --git a/drivers/watchdog/intel-mid_wdt.c b/drivers/watchdog/intel-mid_wdt.c new file mode 100644 index 000000000000..6339c6351454 --- /dev/null +++ b/drivers/watchdog/intel-mid_wdt.c @@ -0,0 +1,209 @@ +/* + * intel-mid_wdt: generic Intel MID SCU watchdog driver + * + * Platforms supported so far: + * - Merrifield only + * + * Copyright (C) 2014 Intel Corporation. All rights reserved. + * Contact: David Cohen + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General + * Public License as published by the Free Software Foundation. + */ + +#include +#include +#include +#include +#include + +#include +#include + +#define IPC_WATCHDOG 0xf8 + +#define MID_WDT_PRETIMEOUT 15 +#define MID_WDT_TIMEOUT_MIN (1 + MID_WDT_PRETIMEOUT) +#define MID_WDT_TIMEOUT_MAX 170 +#define MID_WDT_DEFAULT_TIMEOUT 90 + +/* SCU watchdog messages */ +enum { + SCU_WATCHDOG_START = 0, + SCU_WATCHDOG_STOP, + SCU_WATCHDOG_KEEPALIVE, +}; + +static inline int wdt_command(int sub, u32 *in, int inlen) +{ + return intel_scu_ipc_command(IPC_WATCHDOG, sub, in, inlen, NULL, 0); +} + +static int wdt_start(struct watchdog_device *wd) +{ + int ret, in_size; + int timeout = wd->timeout; + struct ipc_wd_start { + u32 pretimeout; + u32 timeout; + } ipc_wd_start = { timeout - MID_WDT_PRETIMEOUT, timeout }; + + /* + * SCU expects the input size for watchdog IPC to + * be based on double-word + */ + in_size = (sizeof(ipc_wd_start) + 3) / 4; + + ret = wdt_command(SCU_WATCHDOG_START, (u32 *)&ipc_wd_start, in_size); + if (ret) { + struct device *dev = watchdog_get_drvdata(wd); + dev_crit(dev, "error starting watchdog: %d\n", ret); + return -EIO; + } + + return 0; +} + +static int wdt_ping(struct watchdog_device *wd) +{ + int ret; + + ret = wdt_command(SCU_WATCHDOG_KEEPALIVE, NULL, 0); + if (ret) { + struct device *dev = watchdog_get_drvdata(wd); + dev_crit(dev, "Error executing keepalive: 0x%x\n", ret); + return -EIO; + } + + return 0; +} + +static int wdt_stop(struct watchdog_device *wd) +{ + int ret; + + ret = wdt_command(SCU_WATCHDOG_STOP, NULL, 0); + if (ret) { + struct device *dev = watchdog_get_drvdata(wd); + dev_crit(dev, "Error stopping watchdog: 0x%x\n", ret); + return -EIO; + } + + return 0; +} + +static irqreturn_t mid_wdt_warning_irq(int irq, void *dev_id) +{ + /* Let's dump some data before panic */ + trigger_all_cpu_backtrace(); + panic("Kernel Watchdog"); + + /* This code should not be reached */ + return IRQ_HANDLED; +} + +/* + * Current driver supports Merrifield only. + * This function will get more generic when necessary. + */ +static int handle_dev_ioapic(struct device *dev, int irq) +{ + int ioapic; + struct io_apic_irq_attr irq_attr; + + ioapic = mp_find_ioapic(irq); + if (ioapic >= 0) { + irq_attr.ioapic = ioapic; + irq_attr.ioapic_pin = irq; + irq_attr.trigger = 1; + irq_attr.polarity = 0; /* Active high */ + io_apic_set_pci_routing(NULL, irq, &irq_attr); + } else { + dev_warn(dev, "can not find interrupt %d in ioapic\n", irq); + return -EINVAL; + } + + return 0; +} + +static const struct watchdog_info mid_wdt_info = { + .identity = "Intel MID SCU watchdog", + .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT, +}; + +static const struct watchdog_ops mid_wdt_ops = { + .owner = THIS_MODULE, + .start = wdt_start, + .stop = wdt_stop, + .ping = wdt_ping, +}; + +static int mid_wdt_probe(struct platform_device *pdev) +{ + struct watchdog_device *wdt_dev; + struct resource *res; + int ret; + int irq; + + wdt_dev = devm_kzalloc(&pdev->dev, sizeof(*wdt_dev), GFP_KERNEL); + if (!wdt_dev) + return -ENOMEM; + + wdt_dev->info = &mid_wdt_info; + wdt_dev->ops = &mid_wdt_ops; + wdt_dev->min_timeout = MID_WDT_TIMEOUT_MIN; + wdt_dev->max_timeout = MID_WDT_TIMEOUT_MAX; + wdt_dev->timeout = MID_WDT_DEFAULT_TIMEOUT; + + watchdog_set_drvdata(wdt_dev, &pdev->dev); + platform_set_drvdata(pdev, wdt_dev); + + res = platform_get_resource(pdev, IORESOURCE_IRQ, 0); + if (!res) { + dev_err(&pdev->dev, "missing IRQ resource\n"); + return -EINVAL; + } + irq = res->start; + + handle_dev_ioapic(&pdev->dev, irq); + ret = devm_request_irq(&pdev->dev, irq, mid_wdt_warning_irq, + IRQF_SHARED | IRQF_NO_SUSPEND, "watchdog", + wdt_dev); + if (ret) { + dev_err(&pdev->dev, "error requesting warning irq %d\n", irq); + return ret; + } + + ret = watchdog_register_device(wdt_dev); + if (ret) { + dev_err(&pdev->dev, "error registering watchdog device\n"); + return ret; + } + + dev_info(&pdev->dev, "Intel MID watchdog device probed\n"); + + return 0; +} + +static int mid_wdt_remove(struct platform_device *pdev) +{ + struct watchdog_device *wd = platform_get_drvdata(pdev); + watchdog_unregister_device(wd); + return 0; +} + +static struct platform_driver mid_wdt_driver = { + .probe = mid_wdt_probe, + .remove = mid_wdt_remove, + .driver = { + .owner = THIS_MODULE, + .name = "intel_mid_wdt", + }, +}; + +module_platform_driver(mid_wdt_driver); + +MODULE_AUTHOR("David Cohen "); +MODULE_DESCRIPTION("Watchdog Driver for Intel MID platform"); +MODULE_LICENSE("GPL"); -- 1.9.1