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committed 487722cf2d6static char __iomem *kern_dog = (char __iomem *)(IO_BASE + (A_SCD_WDOG_CFG_0));/* * Watchdog driver for SiByte SB1 SoCs * * Copyright (C) 2007 OnStor, Inc. * Andrew Sharp <andy.sharp@lsi.com> * * This driver is intended to make the second of two hardware watchdogs * on the Sibyte 12XX and 11XX SoCs available to the user. There are two * such devices available on the SoC, but it seems that there isn't an * enumeration class for watchdogs in Linux like there is for RTCs. * The second is used rather than the first because it uses IRQ 1, * thereby avoiding all that IRQ 0 problematic nonsense. * * I have not tried this driver on a 1480 processor; it might work * just well enough to really screw things up. * * It is a simple timer, and there is an interrupt that is raised the * first time the timer expires. The second time it expires, the chip * is reset and there is no way to redirect that NMI. Which could * be problematic in some cases where this chip is sitting on the HT * bus and has just taken responsibility for providing a cache block. * Since the reset can't be redirected to the external reset pin, it is * possible that other HT connected processors might hang and not reset. * For Linux, a soft reset would probably be even worse than a hard reset. * There you have it. * * The timer takes 23 bits of a 64 bit register (?) as a count value, * and decrements the count every microsecond, for a max value of * 0x7fffff usec or about 8.3ish seconds. * * This watchdog borrows some user semantics from the softdog driver, * in that if you close the fd, it leaves the watchdog running, unless * you previously wrote a 'V' to the fd, in which case it disables * the watchdog when you close the fd like some other drivers. * * Based on various other watchdog drivers, which are probably all * loosely based on something Alan Cox wrote years ago. * * (c) Copyright 1996 Alan Cox <alan@lxorguk.ukuu.org.uk>, * All Rights Reserved. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * version 1 or 2 as published by the Free Software Foundation. * */static DEFINE_SPINLOCK(sbwd_lock);