mirror of https://gitee.com/openkylin/linux.git
756 lines
19 KiB
C
756 lines
19 KiB
C
/*
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* Octeon Watchdog driver
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*
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* Copyright (C) 2007, 2008, 2009, 2010 Cavium Networks
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*
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* Some parts derived from wdt.c
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*
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* (c) Copyright 1996-1997 Alan Cox <alan@lxorguk.ukuu.org.uk>,
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* All Rights Reserved.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*
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* Neither Alan Cox nor CymruNet Ltd. admit liability nor provide
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* warranty for any of this software. This material is provided
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* "AS-IS" and at no charge.
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*
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* (c) Copyright 1995 Alan Cox <alan@lxorguk.ukuu.org.uk>
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*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file "COPYING" in the main directory of this archive
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* for more details.
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*
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*
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* The OCTEON watchdog has a maximum timeout of 2^32 * io_clock.
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* For most systems this is less than 10 seconds, so to allow for
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* software to request longer watchdog heartbeats, we maintain software
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* counters to count multiples of the base rate. If the system locks
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* up in such a manner that we can not run the software counters, the
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* only result is a watchdog reset sooner than was requested. But
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* that is OK, because in this case userspace would likely not be able
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* to do anything anyhow.
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*
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* The hardware watchdog interval we call the period. The OCTEON
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* watchdog goes through several stages, after the first period an
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* irq is asserted, then if it is not reset, after the next period NMI
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* is asserted, then after an additional period a chip wide soft reset.
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* So for the software counters, we reset watchdog after each period
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* and decrement the counter. But for the last two periods we need to
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* let the watchdog progress to the NMI stage so we disable the irq
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* and let it proceed. Once in the NMI, we print the register state
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* to the serial port and then wait for the reset.
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*
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* A watchdog is maintained for each CPU in the system, that way if
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* one CPU suffers a lockup, we also get a register dump and reset.
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* The userspace ping resets the watchdog on all CPUs.
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*
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* Before userspace opens the watchdog device, we still run the
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* watchdogs to catch any lockups that may be kernel related.
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*
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/miscdevice.h>
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#include <linux/interrupt.h>
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#include <linux/watchdog.h>
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#include <linux/cpumask.h>
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#include <linux/bitops.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/string.h>
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#include <linux/delay.h>
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#include <linux/cpu.h>
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#include <linux/smp.h>
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#include <linux/fs.h>
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#include <linux/irq.h>
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#include <asm/mipsregs.h>
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#include <asm/uasm.h>
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#include <asm/octeon/octeon.h>
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/* The count needed to achieve timeout_sec. */
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static unsigned int timeout_cnt;
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/* The maximum period supported. */
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static unsigned int max_timeout_sec;
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/* The current period. */
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static unsigned int timeout_sec;
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/* Set to non-zero when userspace countdown mode active */
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static int do_coundown;
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static unsigned int countdown_reset;
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static unsigned int per_cpu_countdown[NR_CPUS];
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static cpumask_t irq_enabled_cpus;
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#define WD_TIMO 60 /* Default heartbeat = 60 seconds */
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static int heartbeat = WD_TIMO;
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module_param(heartbeat, int, S_IRUGO);
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MODULE_PARM_DESC(heartbeat,
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"Watchdog heartbeat in seconds. (0 < heartbeat, default="
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__MODULE_STRING(WD_TIMO) ")");
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static bool nowayout = WATCHDOG_NOWAYOUT;
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module_param(nowayout, bool, S_IRUGO);
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MODULE_PARM_DESC(nowayout,
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"Watchdog cannot be stopped once started (default="
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__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
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static unsigned long octeon_wdt_is_open;
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static char expect_close;
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static u32 __initdata nmi_stage1_insns[64];
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/* We need one branch and therefore one relocation per target label. */
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static struct uasm_label __initdata labels[5];
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static struct uasm_reloc __initdata relocs[5];
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enum lable_id {
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label_enter_bootloader = 1
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};
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/* Some CP0 registers */
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#define K0 26
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#define C0_CVMMEMCTL 11, 7
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#define C0_STATUS 12, 0
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#define C0_EBASE 15, 1
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#define C0_DESAVE 31, 0
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void octeon_wdt_nmi_stage2(void);
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static void __init octeon_wdt_build_stage1(void)
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{
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int i;
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int len;
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u32 *p = nmi_stage1_insns;
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#ifdef CONFIG_HOTPLUG_CPU
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struct uasm_label *l = labels;
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struct uasm_reloc *r = relocs;
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#endif
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/*
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* For the next few instructions running the debugger may
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* cause corruption of k0 in the saved registers. Since we're
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* about to crash, nobody probably cares.
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*
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* Save K0 into the debug scratch register
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*/
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uasm_i_dmtc0(&p, K0, C0_DESAVE);
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uasm_i_mfc0(&p, K0, C0_STATUS);
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#ifdef CONFIG_HOTPLUG_CPU
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uasm_il_bbit0(&p, &r, K0, ilog2(ST0_NMI), label_enter_bootloader);
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#endif
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/* Force 64-bit addressing enabled */
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uasm_i_ori(&p, K0, K0, ST0_UX | ST0_SX | ST0_KX);
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uasm_i_mtc0(&p, K0, C0_STATUS);
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#ifdef CONFIG_HOTPLUG_CPU
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uasm_i_mfc0(&p, K0, C0_EBASE);
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/* Coreid number in K0 */
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uasm_i_andi(&p, K0, K0, 0xf);
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/* 8 * coreid in bits 16-31 */
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uasm_i_dsll_safe(&p, K0, K0, 3 + 16);
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uasm_i_ori(&p, K0, K0, 0x8001);
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uasm_i_dsll_safe(&p, K0, K0, 16);
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uasm_i_ori(&p, K0, K0, 0x0700);
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uasm_i_drotr_safe(&p, K0, K0, 32);
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/*
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* Should result in: 0x8001,0700,0000,8*coreid which is
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* CVMX_CIU_WDOGX(coreid) - 0x0500
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*
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* Now ld K0, CVMX_CIU_WDOGX(coreid)
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*/
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uasm_i_ld(&p, K0, 0x500, K0);
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/*
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* If bit one set handle the NMI as a watchdog event.
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* otherwise transfer control to bootloader.
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*/
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uasm_il_bbit0(&p, &r, K0, 1, label_enter_bootloader);
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uasm_i_nop(&p);
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#endif
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/* Clear Dcache so cvmseg works right. */
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uasm_i_cache(&p, 1, 0, 0);
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/* Use K0 to do a read/modify/write of CVMMEMCTL */
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uasm_i_dmfc0(&p, K0, C0_CVMMEMCTL);
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/* Clear out the size of CVMSEG */
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uasm_i_dins(&p, K0, 0, 0, 6);
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/* Set CVMSEG to its largest value */
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uasm_i_ori(&p, K0, K0, 0x1c0 | 54);
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/* Store the CVMMEMCTL value */
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uasm_i_dmtc0(&p, K0, C0_CVMMEMCTL);
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/* Load the address of the second stage handler */
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UASM_i_LA(&p, K0, (long)octeon_wdt_nmi_stage2);
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uasm_i_jr(&p, K0);
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uasm_i_dmfc0(&p, K0, C0_DESAVE);
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#ifdef CONFIG_HOTPLUG_CPU
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uasm_build_label(&l, p, label_enter_bootloader);
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/* Jump to the bootloader and restore K0 */
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UASM_i_LA(&p, K0, (long)octeon_bootloader_entry_addr);
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uasm_i_jr(&p, K0);
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uasm_i_dmfc0(&p, K0, C0_DESAVE);
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#endif
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uasm_resolve_relocs(relocs, labels);
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len = (int)(p - nmi_stage1_insns);
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pr_debug("Synthesized NMI stage 1 handler (%d instructions)\n", len);
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pr_debug("\t.set push\n");
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pr_debug("\t.set noreorder\n");
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for (i = 0; i < len; i++)
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pr_debug("\t.word 0x%08x\n", nmi_stage1_insns[i]);
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pr_debug("\t.set pop\n");
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if (len > 32)
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panic("NMI stage 1 handler exceeds 32 instructions, was %d\n", len);
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}
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static int cpu2core(int cpu)
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{
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#ifdef CONFIG_SMP
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return cpu_logical_map(cpu);
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#else
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return cvmx_get_core_num();
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#endif
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}
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static int core2cpu(int coreid)
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{
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#ifdef CONFIG_SMP
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return cpu_number_map(coreid);
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#else
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return 0;
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#endif
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}
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/**
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* Poke the watchdog when an interrupt is received
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*
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* @cpl:
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* @dev_id:
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*
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* Returns
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*/
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static irqreturn_t octeon_wdt_poke_irq(int cpl, void *dev_id)
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{
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unsigned int core = cvmx_get_core_num();
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int cpu = core2cpu(core);
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if (do_coundown) {
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if (per_cpu_countdown[cpu] > 0) {
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/* We're alive, poke the watchdog */
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cvmx_write_csr(CVMX_CIU_PP_POKEX(core), 1);
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per_cpu_countdown[cpu]--;
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} else {
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/* Bad news, you are about to reboot. */
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disable_irq_nosync(cpl);
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cpumask_clear_cpu(cpu, &irq_enabled_cpus);
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}
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} else {
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/* Not open, just ping away... */
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cvmx_write_csr(CVMX_CIU_PP_POKEX(core), 1);
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}
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return IRQ_HANDLED;
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}
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/* From setup.c */
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extern int prom_putchar(char c);
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/**
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* Write a string to the uart
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*
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* @str: String to write
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*/
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static void octeon_wdt_write_string(const char *str)
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{
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/* Just loop writing one byte at a time */
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while (*str)
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prom_putchar(*str++);
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}
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/**
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* Write a hex number out of the uart
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*
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* @value: Number to display
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* @digits: Number of digits to print (1 to 16)
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*/
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static void octeon_wdt_write_hex(u64 value, int digits)
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{
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int d;
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int v;
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for (d = 0; d < digits; d++) {
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v = (value >> ((digits - d - 1) * 4)) & 0xf;
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if (v >= 10)
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prom_putchar('a' + v - 10);
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else
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prom_putchar('0' + v);
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}
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}
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const char *reg_name[] = {
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"$0", "at", "v0", "v1", "a0", "a1", "a2", "a3",
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"a4", "a5", "a6", "a7", "t0", "t1", "t2", "t3",
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"s0", "s1", "s2", "s3", "s4", "s5", "s6", "s7",
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"t8", "t9", "k0", "k1", "gp", "sp", "s8", "ra"
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};
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/**
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* NMI stage 3 handler. NMIs are handled in the following manner:
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* 1) The first NMI handler enables CVMSEG and transfers from
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* the bootbus region into normal memory. It is careful to not
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* destroy any registers.
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* 2) The second stage handler uses CVMSEG to save the registers
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* and create a stack for C code. It then calls the third level
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* handler with one argument, a pointer to the register values.
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* 3) The third, and final, level handler is the following C
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* function that prints out some useful infomration.
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*
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* @reg: Pointer to register state before the NMI
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*/
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void octeon_wdt_nmi_stage3(u64 reg[32])
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{
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u64 i;
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unsigned int coreid = cvmx_get_core_num();
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/*
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* Save status and cause early to get them before any changes
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* might happen.
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*/
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u64 cp0_cause = read_c0_cause();
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u64 cp0_status = read_c0_status();
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u64 cp0_error_epc = read_c0_errorepc();
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u64 cp0_epc = read_c0_epc();
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/* Delay so output from all cores output is not jumbled together. */
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__delay(100000000ull * coreid);
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octeon_wdt_write_string("\r\n*** NMI Watchdog interrupt on Core 0x");
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octeon_wdt_write_hex(coreid, 1);
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octeon_wdt_write_string(" ***\r\n");
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for (i = 0; i < 32; i++) {
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octeon_wdt_write_string("\t");
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octeon_wdt_write_string(reg_name[i]);
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octeon_wdt_write_string("\t0x");
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octeon_wdt_write_hex(reg[i], 16);
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if (i & 1)
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octeon_wdt_write_string("\r\n");
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}
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octeon_wdt_write_string("\terr_epc\t0x");
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octeon_wdt_write_hex(cp0_error_epc, 16);
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octeon_wdt_write_string("\tepc\t0x");
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octeon_wdt_write_hex(cp0_epc, 16);
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octeon_wdt_write_string("\r\n");
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octeon_wdt_write_string("\tstatus\t0x");
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octeon_wdt_write_hex(cp0_status, 16);
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octeon_wdt_write_string("\tcause\t0x");
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octeon_wdt_write_hex(cp0_cause, 16);
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octeon_wdt_write_string("\r\n");
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octeon_wdt_write_string("\tsum0\t0x");
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octeon_wdt_write_hex(cvmx_read_csr(CVMX_CIU_INTX_SUM0(coreid * 2)), 16);
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octeon_wdt_write_string("\ten0\t0x");
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octeon_wdt_write_hex(cvmx_read_csr(CVMX_CIU_INTX_EN0(coreid * 2)), 16);
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octeon_wdt_write_string("\r\n");
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octeon_wdt_write_string("*** Chip soft reset soon ***\r\n");
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}
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static void octeon_wdt_disable_interrupt(int cpu)
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{
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unsigned int core;
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unsigned int irq;
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union cvmx_ciu_wdogx ciu_wdog;
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core = cpu2core(cpu);
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irq = OCTEON_IRQ_WDOG0 + core;
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/* Poke the watchdog to clear out its state */
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cvmx_write_csr(CVMX_CIU_PP_POKEX(core), 1);
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/* Disable the hardware. */
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ciu_wdog.u64 = 0;
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cvmx_write_csr(CVMX_CIU_WDOGX(core), ciu_wdog.u64);
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free_irq(irq, octeon_wdt_poke_irq);
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}
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static void octeon_wdt_setup_interrupt(int cpu)
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{
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unsigned int core;
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unsigned int irq;
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union cvmx_ciu_wdogx ciu_wdog;
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core = cpu2core(cpu);
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/* Disable it before doing anything with the interrupts. */
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ciu_wdog.u64 = 0;
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cvmx_write_csr(CVMX_CIU_WDOGX(core), ciu_wdog.u64);
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per_cpu_countdown[cpu] = countdown_reset;
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irq = OCTEON_IRQ_WDOG0 + core;
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if (request_irq(irq, octeon_wdt_poke_irq,
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IRQF_NO_THREAD, "octeon_wdt", octeon_wdt_poke_irq))
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panic("octeon_wdt: Couldn't obtain irq %d", irq);
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cpumask_set_cpu(cpu, &irq_enabled_cpus);
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/* Poke the watchdog to clear out its state */
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cvmx_write_csr(CVMX_CIU_PP_POKEX(core), 1);
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/* Finally enable the watchdog now that all handlers are installed */
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ciu_wdog.u64 = 0;
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ciu_wdog.s.len = timeout_cnt;
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ciu_wdog.s.mode = 3; /* 3 = Interrupt + NMI + Soft-Reset */
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cvmx_write_csr(CVMX_CIU_WDOGX(core), ciu_wdog.u64);
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}
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static int octeon_wdt_cpu_callback(struct notifier_block *nfb,
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unsigned long action, void *hcpu)
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{
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unsigned int cpu = (unsigned long)hcpu;
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switch (action) {
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case CPU_DOWN_PREPARE:
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octeon_wdt_disable_interrupt(cpu);
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break;
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case CPU_ONLINE:
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case CPU_DOWN_FAILED:
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octeon_wdt_setup_interrupt(cpu);
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break;
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default:
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break;
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}
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return NOTIFY_OK;
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}
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static void octeon_wdt_ping(void)
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{
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int cpu;
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int coreid;
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for_each_online_cpu(cpu) {
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coreid = cpu2core(cpu);
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cvmx_write_csr(CVMX_CIU_PP_POKEX(coreid), 1);
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per_cpu_countdown[cpu] = countdown_reset;
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if ((countdown_reset || !do_coundown) &&
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!cpumask_test_cpu(cpu, &irq_enabled_cpus)) {
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/* We have to enable the irq */
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int irq = OCTEON_IRQ_WDOG0 + coreid;
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enable_irq(irq);
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cpumask_set_cpu(cpu, &irq_enabled_cpus);
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}
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}
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}
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static void octeon_wdt_calc_parameters(int t)
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{
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unsigned int periods;
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timeout_sec = max_timeout_sec;
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/*
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* Find the largest interrupt period, that can evenly divide
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* the requested heartbeat time.
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*/
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while ((t % timeout_sec) != 0)
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timeout_sec--;
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periods = t / timeout_sec;
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/*
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* The last two periods are after the irq is disabled, and
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|
* then to the nmi, so we subtract them off.
|
|
*/
|
|
|
|
countdown_reset = periods > 2 ? periods - 2 : 0;
|
|
heartbeat = t;
|
|
timeout_cnt = ((octeon_get_io_clock_rate() >> 8) * timeout_sec) >> 8;
|
|
}
|
|
|
|
static int octeon_wdt_set_heartbeat(int t)
|
|
{
|
|
int cpu;
|
|
int coreid;
|
|
union cvmx_ciu_wdogx ciu_wdog;
|
|
|
|
if (t <= 0)
|
|
return -1;
|
|
|
|
octeon_wdt_calc_parameters(t);
|
|
|
|
for_each_online_cpu(cpu) {
|
|
coreid = cpu2core(cpu);
|
|
cvmx_write_csr(CVMX_CIU_PP_POKEX(coreid), 1);
|
|
ciu_wdog.u64 = 0;
|
|
ciu_wdog.s.len = timeout_cnt;
|
|
ciu_wdog.s.mode = 3; /* 3 = Interrupt + NMI + Soft-Reset */
|
|
cvmx_write_csr(CVMX_CIU_WDOGX(coreid), ciu_wdog.u64);
|
|
cvmx_write_csr(CVMX_CIU_PP_POKEX(coreid), 1);
|
|
}
|
|
octeon_wdt_ping(); /* Get the irqs back on. */
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* octeon_wdt_write:
|
|
* @file: file handle to the watchdog
|
|
* @buf: buffer to write (unused as data does not matter here
|
|
* @count: count of bytes
|
|
* @ppos: pointer to the position to write. No seeks allowed
|
|
*
|
|
* A write to a watchdog device is defined as a keepalive signal. Any
|
|
* write of data will do, as we we don't define content meaning.
|
|
*/
|
|
|
|
static ssize_t octeon_wdt_write(struct file *file, const char __user *buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
if (count) {
|
|
if (!nowayout) {
|
|
size_t i;
|
|
|
|
/* In case it was set long ago */
|
|
expect_close = 0;
|
|
|
|
for (i = 0; i != count; i++) {
|
|
char c;
|
|
if (get_user(c, buf + i))
|
|
return -EFAULT;
|
|
if (c == 'V')
|
|
expect_close = 1;
|
|
}
|
|
}
|
|
octeon_wdt_ping();
|
|
}
|
|
return count;
|
|
}
|
|
|
|
/**
|
|
* octeon_wdt_ioctl:
|
|
* @file: file handle to the device
|
|
* @cmd: watchdog command
|
|
* @arg: argument pointer
|
|
*
|
|
* The watchdog API defines a common set of functions for all
|
|
* watchdogs according to their available features. We only
|
|
* actually usefully support querying capabilities and setting
|
|
* the timeout.
|
|
*/
|
|
|
|
static long octeon_wdt_ioctl(struct file *file, unsigned int cmd,
|
|
unsigned long arg)
|
|
{
|
|
void __user *argp = (void __user *)arg;
|
|
int __user *p = argp;
|
|
int new_heartbeat;
|
|
|
|
static struct watchdog_info ident = {
|
|
.options = WDIOF_SETTIMEOUT|
|
|
WDIOF_MAGICCLOSE|
|
|
WDIOF_KEEPALIVEPING,
|
|
.firmware_version = 1,
|
|
.identity = "OCTEON",
|
|
};
|
|
|
|
switch (cmd) {
|
|
case WDIOC_GETSUPPORT:
|
|
return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
|
|
case WDIOC_GETSTATUS:
|
|
case WDIOC_GETBOOTSTATUS:
|
|
return put_user(0, p);
|
|
case WDIOC_KEEPALIVE:
|
|
octeon_wdt_ping();
|
|
return 0;
|
|
case WDIOC_SETTIMEOUT:
|
|
if (get_user(new_heartbeat, p))
|
|
return -EFAULT;
|
|
if (octeon_wdt_set_heartbeat(new_heartbeat))
|
|
return -EINVAL;
|
|
/* Fall through. */
|
|
case WDIOC_GETTIMEOUT:
|
|
return put_user(heartbeat, p);
|
|
default:
|
|
return -ENOTTY;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* octeon_wdt_open:
|
|
* @inode: inode of device
|
|
* @file: file handle to device
|
|
*
|
|
* The watchdog device has been opened. The watchdog device is single
|
|
* open and on opening we do a ping to reset the counters.
|
|
*/
|
|
|
|
static int octeon_wdt_open(struct inode *inode, struct file *file)
|
|
{
|
|
if (test_and_set_bit(0, &octeon_wdt_is_open))
|
|
return -EBUSY;
|
|
/*
|
|
* Activate
|
|
*/
|
|
octeon_wdt_ping();
|
|
do_coundown = 1;
|
|
return nonseekable_open(inode, file);
|
|
}
|
|
|
|
/**
|
|
* octeon_wdt_release:
|
|
* @inode: inode to board
|
|
* @file: file handle to board
|
|
*
|
|
* The watchdog has a configurable API. There is a religious dispute
|
|
* between people who want their watchdog to be able to shut down and
|
|
* those who want to be sure if the watchdog manager dies the machine
|
|
* reboots. In the former case we disable the counters, in the latter
|
|
* case you have to open it again very soon.
|
|
*/
|
|
|
|
static int octeon_wdt_release(struct inode *inode, struct file *file)
|
|
{
|
|
if (expect_close) {
|
|
do_coundown = 0;
|
|
octeon_wdt_ping();
|
|
} else {
|
|
pr_crit("WDT device closed unexpectedly. WDT will not stop!\n");
|
|
}
|
|
clear_bit(0, &octeon_wdt_is_open);
|
|
expect_close = 0;
|
|
return 0;
|
|
}
|
|
|
|
static const struct file_operations octeon_wdt_fops = {
|
|
.owner = THIS_MODULE,
|
|
.llseek = no_llseek,
|
|
.write = octeon_wdt_write,
|
|
.unlocked_ioctl = octeon_wdt_ioctl,
|
|
.open = octeon_wdt_open,
|
|
.release = octeon_wdt_release,
|
|
};
|
|
|
|
static struct miscdevice octeon_wdt_miscdev = {
|
|
.minor = WATCHDOG_MINOR,
|
|
.name = "watchdog",
|
|
.fops = &octeon_wdt_fops,
|
|
};
|
|
|
|
static struct notifier_block octeon_wdt_cpu_notifier = {
|
|
.notifier_call = octeon_wdt_cpu_callback,
|
|
};
|
|
|
|
|
|
/**
|
|
* Module/ driver initialization.
|
|
*
|
|
* Returns Zero on success
|
|
*/
|
|
static int __init octeon_wdt_init(void)
|
|
{
|
|
int i;
|
|
int ret;
|
|
int cpu;
|
|
u64 *ptr;
|
|
|
|
/*
|
|
* Watchdog time expiration length = The 16 bits of LEN
|
|
* represent the most significant bits of a 24 bit decrementer
|
|
* that decrements every 256 cycles.
|
|
*
|
|
* Try for a timeout of 5 sec, if that fails a smaller number
|
|
* of even seconds,
|
|
*/
|
|
max_timeout_sec = 6;
|
|
do {
|
|
max_timeout_sec--;
|
|
timeout_cnt = ((octeon_get_io_clock_rate() >> 8) * max_timeout_sec) >> 8;
|
|
} while (timeout_cnt > 65535);
|
|
|
|
BUG_ON(timeout_cnt == 0);
|
|
|
|
octeon_wdt_calc_parameters(heartbeat);
|
|
|
|
pr_info("Initial granularity %d Sec\n", timeout_sec);
|
|
|
|
ret = misc_register(&octeon_wdt_miscdev);
|
|
if (ret) {
|
|
pr_err("cannot register miscdev on minor=%d (err=%d)\n",
|
|
WATCHDOG_MINOR, ret);
|
|
goto out;
|
|
}
|
|
|
|
/* Build the NMI handler ... */
|
|
octeon_wdt_build_stage1();
|
|
|
|
/* ... and install it. */
|
|
ptr = (u64 *) nmi_stage1_insns;
|
|
for (i = 0; i < 16; i++) {
|
|
cvmx_write_csr(CVMX_MIO_BOOT_LOC_ADR, i * 8);
|
|
cvmx_write_csr(CVMX_MIO_BOOT_LOC_DAT, ptr[i]);
|
|
}
|
|
cvmx_write_csr(CVMX_MIO_BOOT_LOC_CFGX(0), 0x81fc0000);
|
|
|
|
cpumask_clear(&irq_enabled_cpus);
|
|
|
|
cpu_notifier_register_begin();
|
|
for_each_online_cpu(cpu)
|
|
octeon_wdt_setup_interrupt(cpu);
|
|
|
|
__register_hotcpu_notifier(&octeon_wdt_cpu_notifier);
|
|
cpu_notifier_register_done();
|
|
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* Module / driver shutdown
|
|
*/
|
|
static void __exit octeon_wdt_cleanup(void)
|
|
{
|
|
int cpu;
|
|
|
|
misc_deregister(&octeon_wdt_miscdev);
|
|
|
|
cpu_notifier_register_begin();
|
|
__unregister_hotcpu_notifier(&octeon_wdt_cpu_notifier);
|
|
|
|
for_each_online_cpu(cpu) {
|
|
int core = cpu2core(cpu);
|
|
/* Disable the watchdog */
|
|
cvmx_write_csr(CVMX_CIU_WDOGX(core), 0);
|
|
/* Free the interrupt handler */
|
|
free_irq(OCTEON_IRQ_WDOG0 + core, octeon_wdt_poke_irq);
|
|
}
|
|
|
|
cpu_notifier_register_done();
|
|
|
|
/*
|
|
* Disable the boot-bus memory, the code it points to is soon
|
|
* to go missing.
|
|
*/
|
|
cvmx_write_csr(CVMX_MIO_BOOT_LOC_CFGX(0), 0);
|
|
}
|
|
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_AUTHOR("Cavium Networks <support@caviumnetworks.com>");
|
|
MODULE_DESCRIPTION("Cavium Networks Octeon Watchdog driver.");
|
|
module_init(octeon_wdt_init);
|
|
module_exit(octeon_wdt_cleanup);
|