/* * Ralink RT288x/RT3xxx/MT76xx built-in hardware watchdog timer * * Copyright (C) 2011 Gabor Juhos * Copyright (C) 2013 John Crispin * * This driver was based on: drivers/watchdog/softdog.c * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as published * by the Free Software Foundation. */ #include #include #include #include #include #include #include #include #define SYSC_RSTSTAT 0x38 #define WDT_RST_CAUSE BIT(1) #define RALINK_WDT_TIMEOUT 30 #define RALINK_WDT_PRESCALE 65536 #define TIMER_REG_TMR1LOAD 0x00 #define TIMER_REG_TMR1CTL 0x08 #define TMRSTAT_TMR1RST BIT(5) #define TMR1CTL_ENABLE BIT(7) #define TMR1CTL_MODE_SHIFT 4 #define TMR1CTL_MODE_MASK 0x3 #define TMR1CTL_MODE_FREE_RUNNING 0x0 #define TMR1CTL_MODE_PERIODIC 0x1 #define TMR1CTL_MODE_TIMEOUT 0x2 #define TMR1CTL_MODE_WDT 0x3 #define TMR1CTL_PRESCALE_MASK 0xf #define TMR1CTL_PRESCALE_65536 0xf static struct clk *rt288x_wdt_clk; static unsigned long rt288x_wdt_freq; static void __iomem *rt288x_wdt_base; static struct reset_control *rt288x_wdt_reset; static bool nowayout = WATCHDOG_NOWAYOUT; module_param(nowayout, bool, 0); MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); static inline void rt_wdt_w32(unsigned reg, u32 val) { iowrite32(val, rt288x_wdt_base + reg); } static inline u32 rt_wdt_r32(unsigned reg) { return ioread32(rt288x_wdt_base + reg); } static int rt288x_wdt_ping(struct watchdog_device *w) { rt_wdt_w32(TIMER_REG_TMR1LOAD, w->timeout * rt288x_wdt_freq); return 0; } static int rt288x_wdt_start(struct watchdog_device *w) { u32 t; t = rt_wdt_r32(TIMER_REG_TMR1CTL); t &= ~(TMR1CTL_MODE_MASK << TMR1CTL_MODE_SHIFT | TMR1CTL_PRESCALE_MASK); t |= (TMR1CTL_MODE_WDT << TMR1CTL_MODE_SHIFT | TMR1CTL_PRESCALE_65536); rt_wdt_w32(TIMER_REG_TMR1CTL, t); rt288x_wdt_ping(w); t = rt_wdt_r32(TIMER_REG_TMR1CTL); t |= TMR1CTL_ENABLE; rt_wdt_w32(TIMER_REG_TMR1CTL, t); return 0; } static int rt288x_wdt_stop(struct watchdog_device *w) { u32 t; rt288x_wdt_ping(w); t = rt_wdt_r32(TIMER_REG_TMR1CTL); t &= ~TMR1CTL_ENABLE; rt_wdt_w32(TIMER_REG_TMR1CTL, t); return 0; } static int rt288x_wdt_set_timeout(struct watchdog_device *w, unsigned int t) { w->timeout = t; rt288x_wdt_ping(w); return 0; } static int rt288x_wdt_bootcause(void) { if (rt_sysc_r32(SYSC_RSTSTAT) & WDT_RST_CAUSE) return WDIOF_CARDRESET; return 0; } static struct watchdog_info rt288x_wdt_info = { .identity = "Ralink Watchdog", .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, }; static struct watchdog_ops rt288x_wdt_ops = { .owner = THIS_MODULE, .start = rt288x_wdt_start, .stop = rt288x_wdt_stop, .ping = rt288x_wdt_ping, .set_timeout = rt288x_wdt_set_timeout, }; static struct watchdog_device rt288x_wdt_dev = { .info = &rt288x_wdt_info, .ops = &rt288x_wdt_ops, .min_timeout = 1, }; static int rt288x_wdt_probe(struct platform_device *pdev) { struct resource *res; int ret; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); rt288x_wdt_base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(rt288x_wdt_base)) return PTR_ERR(rt288x_wdt_base); rt288x_wdt_clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(rt288x_wdt_clk)) return PTR_ERR(rt288x_wdt_clk); rt288x_wdt_reset = devm_reset_control_get(&pdev->dev, NULL); if (!IS_ERR(rt288x_wdt_reset)) reset_control_deassert(rt288x_wdt_reset); rt288x_wdt_freq = clk_get_rate(rt288x_wdt_clk) / RALINK_WDT_PRESCALE; rt288x_wdt_dev.bootstatus = rt288x_wdt_bootcause(); rt288x_wdt_dev.max_timeout = (0xfffful / rt288x_wdt_freq); rt288x_wdt_dev.parent = &pdev->dev; watchdog_init_timeout(&rt288x_wdt_dev, rt288x_wdt_dev.max_timeout, &pdev->dev); watchdog_set_nowayout(&rt288x_wdt_dev, nowayout); ret = watchdog_register_device(&rt288x_wdt_dev); if (!ret) dev_info(&pdev->dev, "Initialized\n"); return 0; } static int rt288x_wdt_remove(struct platform_device *pdev) { watchdog_unregister_device(&rt288x_wdt_dev); return 0; } static void rt288x_wdt_shutdown(struct platform_device *pdev) { rt288x_wdt_stop(&rt288x_wdt_dev); } static const struct of_device_id rt288x_wdt_match[] = { { .compatible = "ralink,rt2880-wdt" }, {}, }; MODULE_DEVICE_TABLE(of, rt288x_wdt_match); static struct platform_driver rt288x_wdt_driver = { .probe = rt288x_wdt_probe, .remove = rt288x_wdt_remove, .shutdown = rt288x_wdt_shutdown, .driver = { .name = KBUILD_MODNAME, .of_match_table = rt288x_wdt_match, }, }; module_platform_driver(rt288x_wdt_driver); MODULE_DESCRIPTION("MediaTek/Ralink RT288x/RT3xxx hardware watchdog driver"); MODULE_AUTHOR("Gabor Juhos 54791b276b4000b307339f269d3bf7db877d536f (patch) tree1c2616bd373ce5ea28aac2a53e32f5b5834901ce /include/uapi/video/Kbuild parent5d0e7705774dd412a465896d08d59a81a345c1e4 (diff)parent047487241ff59374fded8c477f21453681f5995c (diff)
Merge branch 'sparc64-non-resumable-user-error-recovery'
Liam R. Howlett says: ==================== sparc64: Recover from userspace non-resumable PIO & MEM errors A non-resumable error from userspace is able to cause a kernel panic or trap loop due to the setup and handling of the queued traps once in the kernel. This patch series addresses both of these issues. The queues are fixed by simply zeroing the memory before use. PIO errors from userspace will result in a SIGBUS being sent to the user process. The MEM errors form userspace will result in a SIGKILL and also cause the offending pages to be claimed so they are no longer used in future tasks. SIGKILL is used to ensure that the process does not try to coredump and result in an attempt to read the memory again from within kernel space. Although there is a HV call to scrub the memory (mem_scrub), there is no easy way to guarantee that the real memory address(es) are not used by other tasks. Clearing the error with mem_scrub would zero the memory and cause the other processes to proceed with bad data. The handling of other non-resumable errors remain unchanged and will cause a panic. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/uapi/video/Kbuild')