drivers/watchdog/octeon-wdt-main.c

1 // SPDX-License-Identifier: GPL-2.0+
5  * Copyright (C) 2007-2017 Cavium, Inc.
11  *	(c) Copyright 1996-1997 Alan Cox <alan@lxorguk.ukuu.org.uk>,
16  *	"AS-IS" and at no charge.
25  * only result is a watchdog reset sooner than was requested.  But
31  * irq is asserted, then if it is not reset, after the next period NMI
32  * is asserted, then after an additional period a chip wide soft reset.
33  * So for the software counters, we reset watchdog after each period
37  * to the serial port and then wait for the reset.
40  * one CPU suffers a lockup, we also get a register dump and reset.
63 #include <asm/octeon/cvmx-boot-vector.h>
64 #include <asm/octeon/cvmx-ciu2-defs.h>
65 #include <asm/octeon/cvmx-rst-defs.h>
81 /* Set to non-zero when userspace countdown mode active */
123  * octeon_wdt_poke_irq - Poke the watchdog when an interrupt is received
140 			per_cpu_countdown[cpu]--;  in octeon_wdt_poke_irq()
157  * octeon_wdt_write_string - Write a string to the uart
169  * octeon_wdt_write_hex() - Write a hex number out of the uart
180 		v = (value >> ((digits - d - 1) * 4)) & 0xf;  in octeon_wdt_write_hex()
182 			prom_putchar('a' + v - 10);  in octeon_wdt_write_hex()
274 	octeon_wdt_write_string("*** Chip soft reset soon ***\r\n");  in octeon_wdt_nmi_stage3()
277 	 * G-30204: We must trigger a soft reset before watchdog  in octeon_wdt_nmi_stage3()
288 		 * not too long.  Do the soft reset before watchdog  in octeon_wdt_nmi_stage3()
392 	/* Finally enable the watchdog now that all handlers are installed */  in octeon_wdt_cpu_online()
395 	ciu_wdog.s.mode = 3;	/* 3 = Interrupt + NMI + Soft-Reset */  in octeon_wdt_cpu_online()
417 			/* We have to enable the irq */  in octeon_wdt_ping()
437 		timeout_sec--;  in octeon_wdt_calc_parameters()
446 	countdown_reset = periods > 2 ? periods - 2 : 0;  in octeon_wdt_calc_parameters()
460 		return -1;  in octeon_wdt_set_timeout()
473 		ciu_wdog.s.mode = 3;	/* 3 = Interrupt + NMI + Soft-Reset */  in octeon_wdt_set_timeout()
515  * octeon_wdt_init - Module/ driver initialization.
526 		return -ENOMEM;  in octeon_wdt_init()
546 		max_timeout_sec--;  in octeon_wdt_init()
587  * octeon_wdt_cleanup - Module / driver shutdown
599 	 * Disable the boot-bus memory, the code it points to is soon  in octeon_wdt_cleanup()