NetBSD/sys/arch/mips/pmon/pmon.c

100 lines
2.7 KiB
C

/* $OpenBSD: pmon.c,v 1.4 2010/02/16 21:29:54 miod Exp $ */
/*
* Copyright (c) 2009 Miodrag Vallat.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <machine/cpu.h>
#include <mips/pmon/pmon.h>
int pmon_argc;
int32_t *pmon_argv;
int32_t *pmon_envp;
void
pmon_init(int32_t argc, int32_t argv, int32_t envp, int32_t callvec)
{
pmon_callvec = callvec;
pmon_argc = argc;
/* sign extend pointers */
pmon_argv = (int32_t *)(vaddr_t)argv;
pmon_envp = (int32_t *)(vaddr_t)envp;
}
const char *
pmon_getarg(const int argno)
{
if (argno < 0 || argno >= pmon_argc)
return NULL;
return (const char *)(vaddr_t)pmon_argv[argno];
}
const char *
pmon_getenv(const char *var)
{
int32_t *envptr = pmon_envp;
const char *envstr;
size_t varlen;
if (envptr == NULL)
return NULL;
varlen = strlen(var);
while (*envptr != 0) {
envstr = (const char *)(vaddr_t)*envptr;
/*
* There is a PMON2000 bug, at least on Lemote Yeeloong,
* which causes it to override part of the environment
* pointers array with the environment data itself.
*
* This only happens on cold boot, and if the BSD kernel
* is loaded without symbols (i.e. no option -k passed
* to the boot command).
*
* Until a suitable workaround is found or the bug is
* fixed, ignore broken environment information and
* tell the user (in case this prevents us from finding
* important information).
*/
if ((vaddr_t)envstr < (vaddr_t)MIPS_KSEG1_START ||
(vaddr_t)envstr >= (vaddr_t)MIPS_KSEG2_START) {
printf("WARNING! CORRUPTED ENVIRONMENT!\n");
printf("Unable to search for %s.\n", var);
#ifdef _STANDALONE
printf("If boot fails, power-cycle the machine.\n");
#else
printf("If the kernel fails to identify the system"
" type, please boot it again with `-k' option.\n");
#endif
/* terminate environment for further calls */
*envptr = 0;
break;
}
if (strncmp(envstr, var, varlen) == 0 &&
envstr[varlen] == '=')
return envstr + varlen + 1;
envptr++;
}
return NULL;
}