NetBSD/sys/arch/sun3/include/dvma.h

83 lines
3.4 KiB
C

/* $NetBSD: dvma.h,v 1.3 1996/02/20 22:06:28 gwr 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 W. 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.
*/
/*
* DVMA (Direct Virtual Memory Access - like DMA)
*
* The Sun3 MMU is presented to secondary masters using DVMA.
* Before such devices can access kernel memory, that memory
* must be mapped into the kernel DVMA space. All DVMA space
* is presented as slave-accessible memory for VME and OBIO
* devices, though not at the same address seen by the CPU.
*
* Relevant parts of virtual memory map are:
*
* 0FE0.0000 monitor map (devices)
* 0FF0.0000 DVMA space
* 0FFE.0000 monitor RAM seg.
* 0FFF.E000 monitor RAM page
*
* Note that while the DVMA harware makes the last 1MB visible
* for secondary masters, the PROM "owns" the last page of it.
* Also note that OBIO devices can actually see the last 16MB
* of kernel virtual space. That can be mostly ignored, except
* when calculating the alias address for slave access.
*/
/*
* To convert an address in DVMA space to a slave address,
* just use a logical AND with one of the following masks.
* To convert back, just logical OR with the base address.
*/
#define DVMA_OBIO_SLAVE_BASE 0x0F000000
#define DVMA_OBIO_SLAVE_MASK 0x00FFffff /* 16MB */
#define DVMA_VME_SLAVE_BASE 0x0FF00000 /* 1MB */
#define DVMA_VME_SLAVE_MASK 0x000Fffff /* 1MB */
/* DVMA is the last 1MB, but the PROM gets the last page. */
#define DVMA_SPACE_START 0x0FF00000
#define DVMA_SPACE_END 0x0FFFE000
/* Allocate/free actual pages of DVMA space. */
caddr_t dvma_malloc(size_t bytes);
void dvma_free(caddr_t addr, size_t bytes);
/* Remap/unmap kernel memory in DVMA space. */
caddr_t dvma_mapin(char *kva, int len);
void dvma_mapout(caddr_t dvma_addr, int len);
/* Convert a kernel DVMA pointer to a slave address. */
long dvma_kvtopa(long kva, int bus);