mirror of
https://sourceware.org/git/glibc.git
synced 2025-11-03 20:53:13 +03:00
280 lines
7.0 KiB
C
280 lines
7.0 KiB
C
/* Copyright (C) 1998-2015 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
Contributed by Phil Blundell, based on the Alpha version by
|
|
David Mosberger.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library. If not, see
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
/* I/O port access on the ARM is something of a fiction. What we do is to
|
|
map an appropriate area of /dev/mem into user space so that a program
|
|
can blast away at the hardware in such a way as to generate I/O cycles
|
|
on the bus. To insulate user code from dependencies on particular
|
|
hardware we don't allow calls to inb() and friends to be inlined, but
|
|
force them to come through code in here every time. Performance-critical
|
|
registers tend to be memory mapped these days so this should be no big
|
|
problem. */
|
|
|
|
/* Once upon a time this file used mprotect to enable and disable
|
|
access to particular areas of I/O space. Unfortunately the
|
|
mprotect syscall also has the side effect of enabling caching for
|
|
the area affected (this is a kernel limitation). So we now just
|
|
enable all the ports all of the time. */
|
|
|
|
#include <errno.h>
|
|
#include <fcntl.h>
|
|
#include <stdio.h>
|
|
#include <ctype.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
|
|
#include <sys/types.h>
|
|
#include <sys/mman.h>
|
|
|
|
#include <linux/version.h>
|
|
#include <sys/sysctl.h>
|
|
|
|
#define PATH_ARM_SYSTYPE "/etc/arm_systype"
|
|
#define PATH_CPUINFO "/proc/cpuinfo"
|
|
|
|
#define MAX_PORT 0x10000
|
|
|
|
static struct {
|
|
unsigned long int base;
|
|
unsigned long int io_base;
|
|
unsigned int shift;
|
|
unsigned int initdone; /* since all the above could be 0 */
|
|
} io;
|
|
|
|
#define IO_BASE_FOOTBRIDGE 0x7c000000
|
|
#define IO_SHIFT_FOOTBRIDGE 0
|
|
|
|
static struct platform {
|
|
const char *name;
|
|
unsigned long int io_base;
|
|
unsigned int shift;
|
|
} platform[] = {
|
|
/* All currently supported platforms are in fact the same. :-) */
|
|
{"Chalice-CATS", IO_BASE_FOOTBRIDGE, IO_SHIFT_FOOTBRIDGE},
|
|
{"DEC-EBSA285", IO_BASE_FOOTBRIDGE, IO_SHIFT_FOOTBRIDGE},
|
|
{"Corel-NetWinder", IO_BASE_FOOTBRIDGE, IO_SHIFT_FOOTBRIDGE},
|
|
{"Rebel-NetWinder", IO_BASE_FOOTBRIDGE, IO_SHIFT_FOOTBRIDGE},
|
|
};
|
|
|
|
#define IO_ADDR(port) (io.base + ((port) << io.shift))
|
|
|
|
/*
|
|
* Initialize I/O system. There are several ways to get the information
|
|
* we need. Each is tried in turn until one succeeds.
|
|
*
|
|
* 1. Sysctl (CTL_BUS, CTL_BUS_ISA, ISA_*). This is the preferred method
|
|
* but not all kernels support it.
|
|
*
|
|
* 2. Read the value (not the contents) of symlink PATH_ARM_SYSTYPE.
|
|
* - If it matches one of the entries in the table above, use the
|
|
* corresponding values.
|
|
* - If it begins with a number, assume this is a previously
|
|
* unsupported system and the values encode, in order,
|
|
* "<io_base>,<port_shift>".
|
|
*
|
|
* 3. Lookup the "system type" field in /proc/cpuinfo. Again, if it
|
|
* matches an entry in the platform[] table, use the corresponding
|
|
* values.
|
|
*/
|
|
|
|
/* The Linux kernel headers renamed this constant between 2.5.26 and
|
|
2.5.27. It was backported to 2.4 between 2.4.22 and 2.4.23. */
|
|
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,23)
|
|
# define BUS_ISA CTL_BUS_ISA
|
|
#endif
|
|
|
|
static int
|
|
init_iosys (void)
|
|
{
|
|
char systype[256];
|
|
int i, n;
|
|
static int iobase_name[] = { CTL_BUS, BUS_ISA, BUS_ISA_PORT_BASE };
|
|
static int ioshift_name[] = { CTL_BUS, BUS_ISA, BUS_ISA_PORT_SHIFT };
|
|
size_t len = sizeof(io.base);
|
|
|
|
if (! __sysctl (iobase_name, 3, &io.io_base, &len, NULL, 0)
|
|
&& ! __sysctl (ioshift_name, 3, &io.shift, &len, NULL, 0))
|
|
{
|
|
io.initdone = 1;
|
|
return 0;
|
|
}
|
|
|
|
n = __readlink (PATH_ARM_SYSTYPE, systype, sizeof (systype) - 1);
|
|
if (n > 0)
|
|
{
|
|
systype[n] = '\0';
|
|
if (isdigit (systype[0]))
|
|
{
|
|
if (sscanf (systype, "%li,%i", &io.io_base, &io.shift) == 2)
|
|
{
|
|
io.initdone = 1;
|
|
return 0;
|
|
}
|
|
/* else we're likely going to fail with the system match below */
|
|
}
|
|
}
|
|
else
|
|
{
|
|
FILE * fp;
|
|
|
|
fp = fopen (PATH_CPUINFO, "rce");
|
|
if (! fp)
|
|
return -1;
|
|
while ((n = fscanf (fp, "Hardware\t: %256[^\n]\n", systype))
|
|
!= EOF)
|
|
{
|
|
if (n == 1)
|
|
break;
|
|
else
|
|
fgets_unlocked (systype, 256, fp);
|
|
}
|
|
fclose (fp);
|
|
|
|
if (n == EOF)
|
|
{
|
|
/* this can happen if the format of /proc/cpuinfo changes... */
|
|
fprintf (stderr,
|
|
"ioperm: Unable to determine system type.\n"
|
|
"\t(May need " PATH_ARM_SYSTYPE " symlink?)\n");
|
|
__set_errno (ENODEV);
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
/* translate systype name into i/o system: */
|
|
for (i = 0; i < sizeof (platform) / sizeof (platform[0]); ++i)
|
|
{
|
|
if (strcmp (platform[i].name, systype) == 0)
|
|
{
|
|
io.shift = platform[i].shift;
|
|
io.io_base = platform[i].io_base;
|
|
io.initdone = 1;
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
/* systype is not a known platform name... */
|
|
__set_errno (ENODEV);
|
|
return -1;
|
|
}
|
|
|
|
int
|
|
_ioperm (unsigned long int from, unsigned long int num, int turn_on)
|
|
{
|
|
if (! io.initdone && init_iosys () < 0)
|
|
return -1;
|
|
|
|
/* this test isn't as silly as it may look like; consider overflows! */
|
|
if (from >= MAX_PORT || from + num > MAX_PORT)
|
|
{
|
|
__set_errno (EINVAL);
|
|
return -1;
|
|
}
|
|
|
|
if (turn_on)
|
|
{
|
|
if (! io.base)
|
|
{
|
|
int fd;
|
|
|
|
fd = __open ("/dev/mem", O_RDWR);
|
|
if (fd < 0)
|
|
return -1;
|
|
|
|
io.base =
|
|
(unsigned long int) __mmap (0, MAX_PORT << io.shift,
|
|
PROT_READ | PROT_WRITE,
|
|
MAP_SHARED, fd, io.io_base);
|
|
__close (fd);
|
|
if ((long) io.base == -1)
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
int
|
|
_iopl (unsigned int level)
|
|
{
|
|
if (level > 3)
|
|
{
|
|
__set_errno (EINVAL);
|
|
return -1;
|
|
}
|
|
if (level)
|
|
{
|
|
return _ioperm (0, MAX_PORT, 1);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
|
|
void
|
|
_outb (unsigned char b, unsigned long int port)
|
|
{
|
|
*((volatile unsigned char *)(IO_ADDR (port))) = b;
|
|
}
|
|
|
|
|
|
void
|
|
_outw (unsigned short b, unsigned long int port)
|
|
{
|
|
*((volatile unsigned short *)(IO_ADDR (port))) = b;
|
|
}
|
|
|
|
|
|
void
|
|
_outl (unsigned int b, unsigned long int port)
|
|
{
|
|
*((volatile unsigned long *)(IO_ADDR (port))) = b;
|
|
}
|
|
|
|
|
|
unsigned int
|
|
_inb (unsigned long int port)
|
|
{
|
|
return *((volatile unsigned char *)(IO_ADDR (port)));
|
|
}
|
|
|
|
|
|
unsigned int
|
|
_inw (unsigned long int port)
|
|
{
|
|
return *((volatile unsigned short *)(IO_ADDR (port)));
|
|
}
|
|
|
|
|
|
unsigned int
|
|
_inl (unsigned long int port)
|
|
{
|
|
return *((volatile unsigned long *)(IO_ADDR (port)));
|
|
}
|
|
|
|
weak_alias (_ioperm, ioperm);
|
|
weak_alias (_iopl, iopl);
|
|
weak_alias (_inb, inb);
|
|
weak_alias (_inw, inw);
|
|
weak_alias (_inl, inl);
|
|
weak_alias (_outb, outb);
|
|
weak_alias (_outw, outw);
|
|
weak_alias (_outl, outl);
|