NetBSD-5.0.2/sys/arch/sun2/sun2/mem.c
/* $NetBSD: mem.c,v 1.16 2007/03/10 22:29:24 thorpej Exp $ */
/*
* Copyright (c) 1982, 1986, 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department.
*
* 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. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
*
* from: @(#)mem.c 8.3 (Berkeley) 1/12/94
*/
/*
* Copyright (c) 1994, 1995 Gordon W. Ross
* Copyright (c) 1993 Adam Glass
* Copyright (c) 1988 University of Utah.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
*
* from: @(#)mem.c 8.3 (Berkeley) 1/12/94
*/
/*
* Memory special file
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: mem.c,v 1.16 2007/03/10 22:29:24 thorpej Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/buf.h>
#include <sys/conf.h>
#include <sys/malloc.h>
#include <sys/proc.h>
#include <sys/uio.h>
#include <uvm/uvm_extern.h>
#include <machine/cpu.h>
#include <machine/leds.h>
#include <machine/mon.h>
#include <machine/pmap.h>
#include <machine/pte.h>
#include <sun2/sun2/machdep.h>
#define DEV_VME16D16 5 /* minor device 5 is /dev/vme16d16 */
#define DEV_VME24D16 6 /* minor device 6 is /dev/vme24d16 */
#define DEV_EEPROM 11 /* minor device 11 is eeprom */
#define DEV_LEDS 13 /* minor device 13 is leds */
static int promacc(void *, int, int);
static void *devzeropage;
dev_type_read(mmrw);
dev_type_ioctl(mmioctl);
dev_type_mmap(mmmmap);
const struct cdevsw mem_cdevsw = {
nullopen, nullclose, mmrw, mmrw, mmioctl,
nostop, notty, nopoll, mmmmap, nokqfilter,
};
/*ARGSUSED*/
int
mmrw(dev_t dev, struct uio *uio, int flags)
{
struct iovec *iov;
vaddr_t o, v;
int c, rw;
int error = 0;
static int physlock;
vm_prot_t prot;
if (minor(dev) == DEV_MEM) {
if (vmmap == 0)
return (EIO);
/* lock against other uses of shared vmmap */
while (physlock > 0) {
physlock++;
error = tsleep((void *)&physlock, PZERO | PCATCH,
"mmrw", 0);
if (error)
return (error);
}
physlock = 1;
}
while (uio->uio_resid > 0 && error == 0) {
iov = uio->uio_iov;
if (iov->iov_len == 0) {
uio->uio_iov++;
uio->uio_iovcnt--;
if (uio->uio_iovcnt < 0)
panic("mmrw");
continue;
}
switch (minor(dev)) {
case DEV_MEM:
v = uio->uio_offset;
/* allow reads only in RAM */
if (v >= avail_end) {
error = EFAULT;
goto unlock;
}
/*
* If the offset (physical address) is outside the
* region of physical memory that is "managed" by
* the pmap system, then we are not allowed to
* call pmap_enter with that physical address.
* Physical 0x0 -> physical 0x2000 is unmapped.
* Everything from 0x2000 to avail_start is mapped
* linearly with physical 0x2000 at virtual 0x2000,
* so redirect the access to /dev/kmem instead.
* This is a better alternative than hacking the
* pmap to deal with requests on unmanaged memory.
* Also note: unlock done at end of function.
*/
if (v < 0x2000) {
error = EFAULT;
goto unlock;
}
if (v < avail_start) {
goto use_kmem;
}
/* Temporarily map the memory at vmmap. */
prot = uio->uio_rw == UIO_READ ? VM_PROT_READ :
VM_PROT_WRITE;
pmap_enter(pmap_kernel(), vmmap,
trunc_page(v), prot, prot|PMAP_WIRED);
pmap_update(pmap_kernel());
o = v & PGOFSET;
c = min(uio->uio_resid, (int)(PAGE_SIZE - o));
error = uiomove((void *)(vmmap + o), c, uio);
pmap_remove(pmap_kernel(), (vaddr_t)vmmap,
(vaddr_t)vmmap + PAGE_SIZE);
pmap_update(pmap_kernel());
break;
case DEV_KMEM:
v = uio->uio_offset;
use_kmem:
/*
* Watch out! You might assume it is OK to copy
* up to MAXPHYS bytes here, but that is wrong.
* The next page might NOT be part of the range:
* (KERNBASE..(KERNBASE+avail_start))
* which is asked for here via the goto in the
* /dev/mem case above. The consequence is that
* we copy one page at a time. No big deal, as
* most requests are less than one page anyway.
*/
o = v & PGOFSET;
c = min(uio->uio_resid, (int)(PAGE_SIZE - o));
rw = (uio->uio_rw == UIO_READ) ? B_READ : B_WRITE;
if (!(uvm_kernacc((void *)v, c, rw) ||
promacc((void *)v, c, rw)))
{
error = EFAULT;
/* Note: case 0 can get here, so must unlock! */
goto unlock;
}
error = uiomove((void *)v, c, uio);
break;
case DEV_NULL:
if (uio->uio_rw == UIO_WRITE)
uio->uio_resid = 0;
return (0);
case DEV_ZERO:
/* Write to /dev/zero is ignored. */
if (uio->uio_rw == UIO_WRITE) {
uio->uio_resid = 0;
return (0);
}
/*
* On the first call, allocate and zero a page
* of memory for use with /dev/zero.
*/
if (devzeropage == NULL) {
devzeropage = (void *)
malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
memset(devzeropage, 0, PAGE_SIZE);
}
c = min(iov->iov_len, PAGE_SIZE);
error = uiomove(devzeropage, c, uio);
break;
case DEV_LEDS:
error = leds_uio(uio);
/* Yes, return (not break) so EOF works. */
return (error);
default:
return (ENXIO);
}
}
/*
* Note the different location of this label, compared with
* other ports. This is because the /dev/mem to /dev/kmem
* redirection above jumps here on error to do its unlock.
*/
unlock:
if (minor(dev) == DEV_MEM) {
if (physlock > 1)
wakeup((void *)&physlock);
physlock = 0;
}
return (error);
}
paddr_t
mmmmap(dev_t dev, off_t off, int prot)
{
/*
* Check address validity.
*/
if (off & PGOFSET)
return (-1);
switch (minor(dev)) {
case DEV_MEM:
/* Allow access only in "managed" RAM. */
if (off < avail_start || off >= avail_end)
break;
return (off);
case DEV_VME16D16:
if (off & 0xffff0000)
break;
off |= 0xff0000;
/* fall through */
case DEV_VME24D16:
if (off & 0xff000000)
break;
return (off | (off & 0x800000 ? PMAP_VME8: PMAP_VME0));
}
return (-1);
}
/*
* Just like uvm_kernacc(), but for the PROM mappings.
* Return non-zero if access at VA is allowed.
*/
static int
promacc(void *va, int len, int rw)
{
vaddr_t sva, eva;
sva = (vaddr_t)va;
eva = (vaddr_t)va + len;
/* Test for the most common case first. */
if (sva < SUN2_PROM_BASE)
return (0);
/* Read in the PROM itself is OK. */
if ((rw == B_READ) && (eva <= SUN2_MONEND))
return (1);
/* otherwise, not OK to touch */
return (0);
}