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machdep.c revision 1.33
      1  1.33    simonb /* $NetBSD: machdep.c,v 1.33 2020/08/17 07:50:42 simonb Exp $ */
      2   1.1   gdamore 
      3   1.1   gdamore /*
      4   1.1   gdamore  * Copyright (c) 2006 Urbana-Champaign Independent Media Center.
      5   1.1   gdamore  * Copyright (c) 2006 Garrett D'Amore.
      6   1.1   gdamore  * All rights reserved.
      7   1.1   gdamore  *
      8   1.1   gdamore  * Portions of this code were written by Garrett D'Amore for the
      9   1.1   gdamore  * Champaign-Urbana Community Wireless Network Project.
     10   1.1   gdamore  *
     11   1.1   gdamore  * Redistribution and use in source and binary forms, with or
     12   1.1   gdamore  * without modification, are permitted provided that the following
     13   1.1   gdamore  * conditions are met:
     14   1.1   gdamore  * 1. Redistributions of source code must retain the above copyright
     15   1.1   gdamore  *    notice, this list of conditions and the following disclaimer.
     16   1.1   gdamore  * 2. Redistributions in binary form must reproduce the above
     17   1.1   gdamore  *    copyright notice, this list of conditions and the following
     18   1.1   gdamore  *    disclaimer in the documentation and/or other materials provided
     19   1.1   gdamore  *    with the distribution.
     20   1.1   gdamore  * 3. All advertising materials mentioning features or use of this
     21   1.1   gdamore  *    software must display the following acknowledgements:
     22   1.1   gdamore  *      This product includes software developed by the Urbana-Champaign
     23   1.1   gdamore  *      Independent Media Center.
     24   1.1   gdamore  *	This product includes software developed by Garrett D'Amore.
     25   1.1   gdamore  * 4. Urbana-Champaign Independent Media Center's name and Garrett
     26   1.1   gdamore  *    D'Amore's name may not be used to endorse or promote products
     27   1.1   gdamore  *    derived from this software without specific prior written permission.
     28   1.1   gdamore  *
     29   1.1   gdamore  * THIS SOFTWARE IS PROVIDED BY THE URBANA-CHAMPAIGN INDEPENDENT
     30   1.1   gdamore  * MEDIA CENTER AND GARRETT D'AMORE ``AS IS'' AND ANY EXPRESS OR
     31   1.1   gdamore  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
     32   1.1   gdamore  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     33   1.1   gdamore  * ARE DISCLAIMED.  IN NO EVENT SHALL THE URBANA-CHAMPAIGN INDEPENDENT
     34   1.1   gdamore  * MEDIA CENTER OR GARRETT D'AMORE BE LIABLE FOR ANY DIRECT, INDIRECT,
     35   1.1   gdamore  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     36   1.1   gdamore  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
     37   1.1   gdamore  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
     38   1.1   gdamore  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
     39   1.1   gdamore  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     40   1.1   gdamore  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
     41   1.1   gdamore  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     42   1.1   gdamore  */
     43   1.1   gdamore /*-
     44   1.1   gdamore  * Copyright (c) 2006 Itronix Inc.
     45   1.1   gdamore  * All rights reserved.
     46   1.1   gdamore  *
     47   1.1   gdamore  * Portions written by Garrett D'Amore for Itronix Inc.
     48   1.1   gdamore  *
     49   1.1   gdamore  * Redistribution and use in source and binary forms, with or without
     50   1.1   gdamore  * modification, are permitted provided that the following conditions
     51   1.1   gdamore  * are met:
     52   1.1   gdamore  * 1. Redistributions of source code must retain the above copyright
     53   1.1   gdamore  *    notice, this list of conditions and the following disclaimer.
     54   1.1   gdamore  * 2. Redistributions in binary form must reproduce the above copyright
     55   1.1   gdamore  *    notice, this list of conditions and the following disclaimer in the
     56   1.1   gdamore  *    documentation and/or other materials provided with the distribution.
     57   1.1   gdamore  * 3. The name of Itronix Inc. may not be used to endorse
     58   1.1   gdamore  *    or promote products derived from this software without specific
     59   1.1   gdamore  *    prior written permission.
     60   1.1   gdamore  *
     61   1.1   gdamore  * THIS SOFTWARE IS PROVIDED BY ITRONIX INC. ``AS IS'' AND
     62   1.1   gdamore  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     63   1.1   gdamore  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     64   1.1   gdamore  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL ITRONIX INC. BE LIABLE FOR ANY
     65   1.1   gdamore  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
     66   1.1   gdamore  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
     67   1.1   gdamore  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
     68   1.1   gdamore  * ON ANY THEORY OF LIABILITY, WHETHER IN
     69   1.1   gdamore  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     70   1.1   gdamore  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     71   1.1   gdamore  * POSSIBILITY OF SUCH DAMAGE.
     72   1.1   gdamore  */
     73  1.24     rmind 
     74   1.1   gdamore /*
     75  1.24     rmind  * Copyright (c) 1988 University of Utah.
     76   1.1   gdamore  * Copyright (c) 1992, 1993
     77   1.1   gdamore  *	The Regents of the University of California.  All rights reserved.
     78   1.1   gdamore  *
     79   1.1   gdamore  * This code is derived from software contributed to Berkeley by
     80   1.1   gdamore  * the Systems Programming Group of the University of Utah Computer
     81   1.1   gdamore  * Science Department, The Mach Operating System project at
     82   1.1   gdamore  * Carnegie-Mellon University and Ralph Campbell.
     83   1.1   gdamore  *
     84   1.1   gdamore  * Redistribution and use in source and binary forms, with or without
     85   1.1   gdamore  * modification, are permitted provided that the following conditions
     86   1.1   gdamore  * are met:
     87   1.1   gdamore  * 1. Redistributions of source code must retain the above copyright
     88   1.1   gdamore  *    notice, this list of conditions and the following disclaimer.
     89   1.1   gdamore  * 2. Redistributions in binary form must reproduce the above copyright
     90   1.1   gdamore  *    notice, this list of conditions and the following disclaimer in the
     91   1.1   gdamore  *    documentation and/or other materials provided with the distribution.
     92   1.1   gdamore  * 3. Neither the name of the University nor the names of its contributors
     93   1.1   gdamore  *    may be used to endorse or promote products derived from this software
     94   1.1   gdamore  *    without specific prior written permission.
     95   1.1   gdamore  *
     96   1.1   gdamore  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     97   1.1   gdamore  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     98   1.1   gdamore  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     99   1.1   gdamore  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
    100   1.1   gdamore  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
    101   1.1   gdamore  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
    102   1.1   gdamore  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
    103   1.1   gdamore  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
    104   1.1   gdamore  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
    105   1.1   gdamore  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
    106   1.1   gdamore  * SUCH DAMAGE.
    107   1.1   gdamore  *
    108   1.1   gdamore  *	@(#)machdep.c	8.3 (Berkeley) 1/12/94
    109   1.1   gdamore  * 	from: Utah Hdr: machdep.c 1.63 91/04/24
    110   1.1   gdamore  */
    111   1.1   gdamore 
    112  1.24     rmind #include <sys/cdefs.h>
    113  1.33    simonb __KERNEL_RCSID(0, "$NetBSD: machdep.c,v 1.33 2020/08/17 07:50:42 simonb Exp $");
    114   1.1   gdamore 
    115   1.1   gdamore #include "opt_ddb.h"
    116   1.1   gdamore #include "opt_kgdb.h"
    117  1.17       apb #include "opt_modular.h"
    118   1.1   gdamore 
    119   1.1   gdamore #include <sys/param.h>
    120  1.27      matt #include <sys/boot_flag.h>
    121  1.27      matt #include <sys/device.h>
    122   1.1   gdamore #include <sys/kernel.h>
    123   1.1   gdamore #include <sys/kcore.h>
    124   1.1   gdamore #include <sys/ksyms.h>
    125  1.27      matt #include <sys/mount.h>
    126  1.27      matt #include <sys/reboot.h>
    127  1.29  christos #include <sys/cpu.h>
    128   1.1   gdamore 
    129   1.1   gdamore #include <uvm/uvm_extern.h>
    130   1.1   gdamore 
    131   1.1   gdamore #include <dev/cons.h>
    132   1.1   gdamore 
    133   1.1   gdamore #include "ksyms.h"
    134   1.1   gdamore 
    135  1.15        ad #if NKSYMS || defined(DDB) || defined(MODULAR)
    136  1.27      matt #include <mips/db_machdep.h>
    137   1.1   gdamore #include <ddb/db_extern.h>
    138   1.1   gdamore #endif
    139   1.1   gdamore 
    140   1.1   gdamore #include <mips/cache.h>
    141   1.1   gdamore #include <mips/locore.h>
    142   1.1   gdamore #include <mips/cpuregs.h>
    143   1.1   gdamore 
    144  1.26      matt #include <mips/atheros/include/platform.h>
    145   1.1   gdamore #include <mips/atheros/include/arbusvar.h>
    146   1.1   gdamore 
    147   1.1   gdamore /* Maps for VM objects. */
    148   1.1   gdamore struct vm_map *phys_map = NULL;
    149   1.1   gdamore 
    150   1.1   gdamore int maxmem;			/* max memory per process */
    151   1.1   gdamore 
    152   1.1   gdamore int mem_cluster_cnt;
    153   1.1   gdamore phys_ram_seg_t mem_clusters[VM_PHYSSEG_MAX];
    154   1.1   gdamore 
    155   1.1   gdamore void	mach_init(void); /* XXX */
    156   1.1   gdamore 
    157  1.33    simonb /* Currently the Atheros kernels only support big endian boards */
    158  1.33    simonb CTASSERT(_BYTE_ORDER == _BIG_ENDIAN);
    159  1.33    simonb 
    160   1.4   gdamore static void
    161   1.4   gdamore cal_timer(void)
    162   1.4   gdamore {
    163   1.4   gdamore 	uint32_t	cntfreq;
    164   1.1   gdamore 
    165  1.26      matt 	cntfreq = curcpu()->ci_cpu_freq = atheros_get_cpu_freq();
    166   1.4   gdamore 
    167   1.4   gdamore 	/* MIPS 4Kc CP0 counts every other clock */
    168  1.25      matt 	if (mips_options.mips_cpu_flags & CPU_MIPS_DOUBLE_COUNT)
    169   1.4   gdamore 		cntfreq /= 2;
    170   1.4   gdamore 
    171  1.25      matt 	curcpu()->ci_cctr_freq = cntfreq;
    172   1.4   gdamore 	curcpu()->ci_cycles_per_hz = (cntfreq + hz / 2) / hz;
    173   1.4   gdamore 
    174  1.12   tsutsui 	/* Compute number of cycles per 1us (1/MHz). 0.5MHz is for roundup. */
    175   1.4   gdamore 	curcpu()->ci_divisor_delay = ((cntfreq + 500000) / 1000000);
    176   1.4   gdamore }
    177   1.1   gdamore 
    178   1.1   gdamore void
    179   1.1   gdamore mach_init(void)
    180   1.1   gdamore {
    181   1.6  christos 	void *kernend;
    182  1.20     rmind 	uint32_t memsize;
    183   1.1   gdamore 
    184   1.1   gdamore 	extern char edata[], end[];	/* XXX */
    185   1.1   gdamore 
    186   1.1   gdamore 	/* clear the BSS segment */
    187   1.6  christos 	kernend = (void *)mips_round_page(end);
    188   1.1   gdamore 
    189   1.7    simonb 	memset(edata, 0, (char *)kernend - edata);
    190   1.1   gdamore 
    191   1.5   gdamore 	/* setup early console */
    192  1.26      matt 	atheros_set_platformsw();
    193   1.5   gdamore 
    194   1.1   gdamore 	/* set CPU model info for sysctl_hw */
    195  1.29  christos 	cpu_setmodel("Atheros %s", atheros_get_cpuname());
    196   1.1   gdamore 
    197   1.1   gdamore 	/*
    198   1.1   gdamore 	 * Set up the exception vectors and CPU-specific function
    199   1.1   gdamore 	 * vectors early on.  We need the wbflush() vector set up
    200   1.1   gdamore 	 * before comcnattach() is called (or at least before the
    201   1.1   gdamore 	 * first printf() after that is called).
    202   1.1   gdamore 	 * Sets up mips_cpu_flags that may be queried by other
    203   1.1   gdamore 	 * functions called during startup.
    204   1.1   gdamore 	 * Also clears the I+D caches.
    205   1.1   gdamore 	 */
    206  1.25      matt 	mips_vector_init(NULL, false);
    207   1.1   gdamore 
    208   1.1   gdamore 	/*
    209   1.1   gdamore 	 * Calibrate timers.
    210   1.1   gdamore 	 */
    211   1.4   gdamore 	cal_timer();
    212   1.1   gdamore 
    213  1.31    cherry 	uvm_md_init();
    214   1.1   gdamore 
    215   1.1   gdamore 	/*
    216   1.1   gdamore 	 * Look at arguments passed to us and compute boothowto.
    217   1.1   gdamore 	 */
    218   1.1   gdamore 	boothowto = RB_AUTOBOOT;
    219   1.1   gdamore #ifdef KADB
    220   1.1   gdamore 	boothowto |= RB_KDB;
    221   1.1   gdamore #endif
    222   1.1   gdamore 
    223   1.1   gdamore 	/*
    224  1.11       imp 	 * This would be a good place to parse a boot command line, if
    225   1.1   gdamore 	 * we got one from the bootloader.  Right now we have no way to
    226   1.1   gdamore 	 * get one from e.g. vxworks.
    227   1.1   gdamore 	 */
    228   1.1   gdamore 
    229   1.1   gdamore 	/*
    230   1.4   gdamore 	 * Determine the memory size.
    231   1.1   gdamore 	 *
    232   1.1   gdamore 	 * Note: Reserve the first page!  That's where the trap
    233   1.1   gdamore 	 * vectors are located.
    234   1.1   gdamore 	 */
    235  1.26      matt 	memsize = atheros_get_memsize();
    236   1.1   gdamore 
    237   1.1   gdamore 	printf("Memory size: 0x%08x\n", memsize);
    238   1.1   gdamore 	physmem = btoc(memsize);
    239   1.1   gdamore 
    240   1.1   gdamore 	mem_clusters[mem_cluster_cnt].start = PAGE_SIZE;
    241   1.1   gdamore 	mem_clusters[mem_cluster_cnt].size =
    242   1.1   gdamore 	    memsize - mem_clusters[mem_cluster_cnt].start;
    243   1.1   gdamore 	mem_cluster_cnt++;
    244   1.1   gdamore 
    245   1.1   gdamore 	/*
    246  1.25      matt 	 * Load the available pages into the VM system.
    247   1.1   gdamore 	 */
    248  1.25      matt 	mips_page_physload(MIPS_KSEG0_START, (vaddr_t)kernend,
    249  1.25      matt 	    mem_clusters, mem_cluster_cnt, NULL, 0);
    250   1.1   gdamore 
    251   1.1   gdamore 	/*
    252   1.1   gdamore 	 * Initialize message buffer (at end of core).
    253   1.1   gdamore 	 */
    254   1.1   gdamore 	mips_init_msgbuf();
    255   1.1   gdamore 
    256   1.1   gdamore 	/*
    257   1.1   gdamore 	 * Initialize the virtual memory system.
    258   1.1   gdamore 	 */
    259   1.1   gdamore 	pmap_bootstrap();
    260   1.1   gdamore 
    261   1.1   gdamore 	/*
    262  1.20     rmind 	 * Allocate uarea page for lwp0 and set it.
    263   1.1   gdamore 	 */
    264  1.21      matt 	mips_init_lwp0_uarea();
    265   1.1   gdamore 
    266   1.1   gdamore 	/*
    267   1.4   gdamore 	 * Initialize busses.
    268   1.1   gdamore 	 */
    269  1.26      matt 	atheros_bus_init();
    270   1.1   gdamore 
    271   1.1   gdamore 	/*
    272   1.1   gdamore 	 * Turn off (ignore) the hardware watchdog.  If we got this
    273   1.1   gdamore 	 * far, then we shouldn't need it anymore.
    274   1.1   gdamore 	 */
    275  1.26      matt 	atheros_wdog_reload(0);
    276   1.1   gdamore 
    277   1.1   gdamore 	/*
    278   1.1   gdamore 	 * Turn off watchpoint that may have been enabled by the
    279   1.1   gdamore 	 * PROM.  VxWorks bootloader seems to leave one set.
    280   1.1   gdamore 	 */
    281   1.1   gdamore 	__asm volatile (
    282  1.25      matt 		"mtc0	$0, $%0\n\t"
    283   1.1   gdamore 		"nop\n\t"
    284  1.25      matt 		"nop\n\t" :: "n"(MIPS_COP_0_WATCH_LO));
    285   1.1   gdamore 
    286   1.1   gdamore 	/*
    287   1.1   gdamore 	 * Initialize debuggers, and break into them, if appropriate.
    288   1.1   gdamore 	 */
    289   1.1   gdamore #ifdef DDB
    290   1.1   gdamore 	if (boothowto & RB_KDB)
    291   1.1   gdamore 		Debugger();
    292   1.1   gdamore #endif
    293   1.1   gdamore }
    294   1.1   gdamore 
    295   1.1   gdamore void
    296   1.1   gdamore consinit(void)
    297   1.1   gdamore {
    298   1.1   gdamore 
    299   1.1   gdamore 	/*
    300   1.1   gdamore 	 * Everything related to console initialization is done
    301   1.1   gdamore 	 * in mach_init().
    302   1.1   gdamore 	 */
    303  1.26      matt 	atheros_consinit();
    304   1.1   gdamore }
    305   1.1   gdamore 
    306   1.1   gdamore void
    307   1.1   gdamore cpu_startup(void)
    308   1.1   gdamore {
    309  1.30      matt 	cpu_startup_common();
    310   1.1   gdamore }
    311   1.1   gdamore 
    312   1.1   gdamore void
    313   1.1   gdamore cpu_reboot(int howto, char *bootstr)
    314   1.1   gdamore {
    315   1.1   gdamore 	static int waittime = -1;
    316   1.1   gdamore 
    317   1.1   gdamore 	/* Take a snapshot before clobbering any registers. */
    318  1.25      matt 	savectx(curpcb);
    319   1.1   gdamore 
    320   1.1   gdamore 	/* If "always halt" was specified as a boot flag, obey. */
    321   1.1   gdamore 	if (boothowto & RB_HALT)
    322   1.1   gdamore 		howto |= RB_HALT;
    323   1.1   gdamore 
    324   1.1   gdamore 	boothowto = howto;
    325   1.1   gdamore 
    326   1.1   gdamore 	/* If system is cold, just halt. */
    327   1.1   gdamore 	if (cold) {
    328   1.1   gdamore 		boothowto |= RB_HALT;
    329   1.1   gdamore 		goto haltsys;
    330   1.1   gdamore 	}
    331   1.1   gdamore 
    332   1.1   gdamore 	if ((boothowto & RB_NOSYNC) == 0 && waittime < 0) {
    333   1.1   gdamore 		waittime = 0;
    334   1.1   gdamore 
    335   1.1   gdamore 		/*
    336   1.1   gdamore 		 * Synchronize the disks....
    337   1.1   gdamore 		 */
    338   1.1   gdamore 		vfs_shutdown();
    339   1.1   gdamore 
    340   1.1   gdamore 		/*
    341   1.1   gdamore 		 * If we've been adjusting the clock, the todr
    342   1.1   gdamore 		 * will be out of synch; adjust it now.
    343   1.1   gdamore 		 */
    344   1.1   gdamore 		resettodr();
    345   1.1   gdamore 	}
    346   1.1   gdamore 
    347   1.1   gdamore 	/* Disable interrupts. */
    348   1.1   gdamore 	splhigh();
    349   1.1   gdamore 
    350   1.1   gdamore 	if (boothowto & RB_DUMP)
    351   1.1   gdamore 		dumpsys();
    352   1.1   gdamore 
    353   1.1   gdamore  haltsys:
    354   1.1   gdamore 	/* Run any shutdown hooks. */
    355   1.1   gdamore 	doshutdownhooks();
    356   1.1   gdamore 
    357  1.14    dyoung 	pmf_system_shutdown(boothowto);
    358  1.14    dyoung 
    359   1.1   gdamore #if 0
    360   1.1   gdamore 	if ((boothowto & RB_POWERDOWN) == RB_POWERDOWN)
    361   1.1   gdamore 		if (board && board->ab_poweroff)
    362   1.1   gdamore 			board->ab_poweroff();
    363   1.1   gdamore #endif
    364   1.1   gdamore 
    365   1.1   gdamore 	/*
    366   1.1   gdamore 	 * Firmware may autoboot (depending on settings), and we cannot pass
    367   1.1   gdamore 	 * flags to it (at least I haven't figured out how to yet), so
    368   1.1   gdamore 	 * we "pseudo-halt" now.
    369   1.1   gdamore 	 */
    370   1.1   gdamore 	if (boothowto & RB_HALT) {
    371   1.1   gdamore 		printf("\n");
    372   1.1   gdamore 		printf("The operating system has halted.\n");
    373   1.1   gdamore 		printf("Please press any key to reboot.\n\n");
    374   1.1   gdamore 		cnpollc(1);	/* For proper keyboard command handling */
    375   1.1   gdamore 		cngetc();
    376   1.1   gdamore 		cnpollc(0);
    377   1.1   gdamore 	}
    378   1.1   gdamore 
    379  1.32   msaitoh 	printf("resetting board...\n\n");
    380   1.1   gdamore 	mips_icache_sync_all();
    381   1.1   gdamore 	mips_dcache_wbinv_all();
    382  1.26      matt 	atheros_reset();
    383   1.1   gdamore 	__asm volatile("jr	%0" :: "r"(MIPS_RESET_EXC_VEC));
    384   1.1   gdamore 	printf("Oops, back from reset\n\nSpinning...");
    385   1.1   gdamore 	for (;;)
    386   1.1   gdamore 		/* spin forever */ ;	/* XXX */
    387   1.1   gdamore 	/*NOTREACHED*/
    388   1.1   gdamore }
    389