libc/libgloss/mn10300/cygmon.c

74 lines
2.0 KiB
C

/* cygmon.c -- Glue code for linking apps to run on top of Cygmon.
*
* Copyright (c) 1998, 1999, 2000, 2001 Red Hat, Inc.
*
* The authors hereby grant permission to use, copy, modify, distribute,
* and license this software and its documentation for any purpose, provided
* that existing copyright notices are retained in all copies and that this
* notice is included verbatim in any distributions. No written agreement,
* license, or royalty fee is required for any of the authorized uses.
* Modifications to this software may be copyrighted by their authors
* and need not follow the licensing terms described here, provided that
* the new terms are clearly indicated on the first page of each file where
* they apply.
*/
#include <errno.h>
// These need to be kept in sync with the definitions in Cygmon.
#define SYS_meminfo 1001
#include "syscall.h"
/* Structure filled in by get_mem_info. Only the size field is
actually used (by sbrk), so the others aren't even filled in. */
struct s_mem
{
unsigned int size;
unsigned int icsize;
unsigned int dcsize;
};
// Perform a system call.
// Unused parameters should be set to 0.
int __trap0(unsigned long func, unsigned long p1, unsigned long p2, unsigned long p3)
{
int ret = 0;
#ifdef __AM33__
{
register unsigned long d0 asm ("d0") = func;
register unsigned long d1 asm ("d1") = p1;
register unsigned long d2 asm ("d2") = p2;
register unsigned long d3 asm ("d3") = p3;
asm volatile (" syscall 0\n"
" nop"
: "+d" (d0) : "d" (d1), "d" (d2), "d" (d3) : "memory");
ret = d0;
}
#endif
if (func == SYS_exit)
{
while (1)
{
asm volatile (" .byte 0xff "); // trigger a breakpoint to drop back into Cygmon
}
}
if (ret != 0)
errno = ret;
return ret;
}
void *
get_mem_info (mem)
struct s_mem *mem;
{
unsigned long totmem = 0, topmem = 0;
register int numbanks;
numbanks = __trap0(SYS_meminfo, (unsigned long)&totmem, (unsigned long)&topmem, 0);
mem->size = totmem;
return (void*)topmem;
}