/* * MOXA ART SoCs watchdog driver. * * Copyright (C) 2013 Jonas Jensen * * Jonas Jensen * * This file is licensed under the terms of the GNU General Public * License version 2. This program is licensed "as is" without any * warranty of any kind, whether express or implied. */ #include #include #include #include #include #include #include #include #define REG_COUNT 0x4 #define REG_MODE 0x8 #define REG_ENABLE 0xC struct moxart_wdt_dev { struct watchdog_device dev; void __iomem *base; unsigned int clock_frequency; }; static int heartbeat; static int moxart_wdt_restart(struct watchdog_device *wdt_dev, unsigned long action, void *data) { struct moxart_wdt_dev *moxart_wdt = watchdog_get_drvdata(wdt_dev); writel(1, moxart_wdt->base + REG_COUNT); writel(0x5ab9, moxart_wdt->base + REG_MODE); writel(0x03, moxart_wdt->base + REG_ENABLE); return 0; } static int moxart_wdt_stop(struct watchdog_device *wdt_dev) { struct moxart_wdt_dev *moxart_wdt = watchdog_get_drvdata(wdt_dev); writel(0, moxart_wdt->base + REG_ENABLE); return 0; } static int moxart_wdt_start(struct watchdog_device *wdt_dev) { struct moxart_wdt_dev *moxart_wdt = watchdog_get_drvdata(wdt_dev); writel(moxart_wdt->clock_frequency * wdt_dev->timeout, moxart_wdt->base + REG_COUNT); writel(0x5ab9, moxart_wdt->base + REG_MODE); writel(0x03, moxart_wdt->base + REG_ENABLE); return 0; } static int moxart_wdt_set_timeout(struct watchdog_device *wdt_dev, unsigned int timeout) { wdt_dev->timeout = timeout; return 0; } static const struct watchdog_info moxart_wdt_info = { .identity = "moxart-wdt", .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, }; static const struct watchdog_ops moxart_wdt_ops = { .owner = THIS_MODULE, .start = moxart_wdt_start, .stop = moxart_wdt_stop, .set_timeout = moxart_wdt_set_timeout, .restart = moxart_wdt_restart, }; static int moxart_wdt_probe(struct platform_device *pdev) { struct moxart_wdt_dev *moxart_wdt; struct device *dev = &pdev->dev; struct device_node *node = dev->of_node; struct resource *res; struct clk *clk; int err; unsigned int max_timeout; bool nowayout = WATCHDOG_NOWAYOUT; moxart_wdt = devm_kzalloc(dev, sizeof(*moxart_wdt), GFP_KERNEL); if (!moxart_wdt) return -ENOMEM; platform_set_drvdata(pdev, moxart_wdt); res = platform_get_resource(pdev, IORESOURCE_MEM, 0); moxart_wdt->base = devm_ioremap_resource(dev, res); if (IS_ERR(moxart_wdt->base)) return PTR_ERR(moxart_wdt->base); clk = of_clk_get(node, 0); if (IS_ERR(clk)) { pr_err("%s: of_clk_get failed\n", __func__); return PTR_ERR(clk); } moxart_wdt->clock_frequency = clk_get_rate(clk); if (moxart_wdt->clock_frequency == 0) { pr_err("%s: incorrect clock frequency\n", __func__); return -EINVAL; } max_timeout = UINT_MAX / moxart_wdt->clock_frequency; moxart_wdt->dev.info = &moxart_wdt_info; moxart_wdt->dev.ops = &moxart_wdt_ops; moxart_wdt->dev.timeout = max_timeout; moxart_wdt->dev.min_timeout = 1; moxart_wdt->dev.max_timeout = max_timeout; moxart_wdt->dev.parent = dev; watchdog_init_timeout(&moxart_wdt->dev, heartbeat, dev); watchdog_set_nowayout(&moxart_wdt->dev, nowayout); watchdog_set_restart_priority(&moxart_wdt->dev, 128); watchdog_set_drvdata(&moxart_wdt->dev, moxart_wdt); err = watchdog_register_device(&moxart_wdt->dev); if (err) return err; dev_dbg(dev, "Watchdog enabled (heartbeat=%d sec, nowayout=%d)\n", moxart_wdt->dev.timeout, nowayout); return 0; } static int moxart_wdt_remove(struct platform_device *pdev) { struct moxart_wdt_dev *moxart_wdt = platform_get_drvdata(pdev); moxart_wdt_stop(&moxart_wdt->dev); return 0; } static const struct of_device_id moxart_watchdog_match[] = { { .compatible = "moxa,moxart-watchdog" }, { }, }; MODULE_DEVICE_TABLE(of, moxart_watchdog_match); static struct platform_driver moxart_wdt_driver = { .probe = moxart_wdt_probe, .remove = moxart_wdt_remove, .driver = { .name = "moxart-watchdog", .of_match_table = moxart_watchdog_match, }, }; module_platform_driver(moxart_wdt_driver); module_param(heartbeat, int, 0); MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds"); MODULE_DESCRIPTION("MOXART watchdog driver"); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Jonas Jensen "); elected'>unified
authorSteven Rostedt (VMware) <rostedt@goodmis.org>2017-01-30 19:27:10 -0500
committerSteven Rostedt (VMware) <rostedt@goodmis.org>2017-01-31 09:13:49 -0500
commit79c6f448c8b79c321e4a1f31f98194e4f6b6cae7 (patch)
tree370efda701f03cccf21e02bb1fdd3b852547d75c /include/dt-bindings/mailbox/tegra186-hsp.h
parent0c744ea4f77d72b3dcebb7a8f2684633ec79be88 (diff)
tracing: Fix hwlat kthread migration
The hwlat tracer creates a kernel thread at start of the tracer. It is pinned to a single CPU and will move to the next CPU after each period of running. If the user modifies the migration thread's affinity, it will not change after that happens. The original code created the thread at the first instance it was called, but later was changed to destroy the thread after the tracer was finished, and would not be created until the next instance of the tracer was established. The code that initialized the affinity was only called on the initial instantiation of the tracer. After that, it was not initialized, and the previous affinity did not match the current newly created one, making it appear that the user modified the thread's affinity when it did not, and the thread failed to migrate again. Cc: stable@vger.kernel.org Fixes: 0330f7aa8ee6 ("tracing: Have hwlat trace migrate across tracing_cpumask CPUs") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'include/dt-bindings/mailbox/tegra186-hsp.h')