NetBSD/sys/arch/sparc/stand/dvma.c

120 lines
3.4 KiB
C

/* $NetBSD: dvma.c,v 1.2 1995/09/17 00:50:56 pk Exp $ */
/*
* Copyright (c) 1995 Gordon W. Ross
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
* 4. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Gordon Ross
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* The easiest way to deal with the need for DVMA mappings is
* to just map the entire third megabyte of RAM into DVMA space.
* That way, dvma_mapin can just compute the DVMA alias address,
* and dvma_mapout does nothing. Note that this assumes all
* standalone programs stay in the range SA_MIN_VA .. SA_MAX_VA
*/
#include <sys/param.h>
#include <machine/pte.h>
#include <machine/ctlreg.h>
#include "promdev.h"
#define DVMA_BASE 0xFFF00000
#define DVMA_MAPLEN 0xE0000 /* 1 MB - 128K (save MONSHORTSEG) */
#define SA_MIN_VA (RELOC - 0x40000) /* XXX - magic constant */
#define SA_MAX_VA (SA_MIN_VA + DVMA_MAPLEN)
void
dvma_init()
{
register int segva, dmava;
dmava = DVMA_BASE;
for (segva = SA_MIN_VA; segva < SA_MAX_VA; segva += NBPSG) {
setsegmap(dmava, getsegmap(segva));
dmava += NBPSG;
}
}
/*
* Convert a local address to a DVMA address.
*/
char *
dvma_mapin(char *addr, size_t len)
{
register int va = (int)addr;
/* Make sure the address is in the DVMA map. */
if ((va < SA_MIN_VA) || (va >= SA_MAX_VA))
panic("dvma_mapin");
va += DVMA_BASE - SA_MIN_VA;
return ((char *)va);
}
/*
* Convert a DVMA address to a local address.
*/
char *
dvma_mapout(char *addr, size_t len)
{
int va = (int)addr;
/* Make sure the address is in the DVMA map. */
if ((va < DVMA_BASE) || (va >= (DVMA_BASE + DVMA_MAPLEN)))
panic("dvma_mapout");
va -= DVMA_BASE - SA_MIN_VA;
return ((char *)va);
}
extern char *alloc __P((int));
char *
dvma_alloc(int len)
{
char *mem;
mem = alloc(len);
if (!mem)
return (mem);
return (dvma_mapin(mem, len));
}
extern void free(void *ptr, int len);
void
dvma_free(char *dvma, int len)
{
char *mem;
mem = dvma_mapout(dvma, len);
if (mem)
free(mem, len);
}