mirror of
https://git.rwth-aachen.de/acs/public/villas/node/
synced 2025-03-30 00:00:11 +01:00
132 lines
3.7 KiB
C
132 lines
3.7 KiB
C
/* Simple program to read/write from/to a pci device from userspace.
|
|
*
|
|
* SPDX-FileCopyrightText: 2010 Bill Farrow <bfarrow@beyondelectronics.us>
|
|
* SPDX-FileCopyrightText: 2023 Institute for Automation of Complex Power Systems, RWTH Aachen University
|
|
*
|
|
* Based on the devmem2.c code
|
|
*
|
|
* SPDX-FileCopyrightText: 2000 Jan-Derk Bakker <J.D.Bakker@its.tudelft.nl>
|
|
* SPDX-License-Identifier: GPL-2.0-or-later
|
|
*/
|
|
|
|
#include <ctype.h>
|
|
#include <errno.h>
|
|
#include <fcntl.h>
|
|
#include <signal.h>
|
|
#include <stdint.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <sys/mman.h>
|
|
#include <sys/types.h>
|
|
#include <termios.h>
|
|
#include <unistd.h>
|
|
|
|
#define PRINT_ERROR \
|
|
do { \
|
|
fprintf(stderr, "Error at line %d, file %s (%d) [%s]\n", __LINE__, \
|
|
__FILE__, errno, strerror(errno)); \
|
|
exit(1); \
|
|
} while (0)
|
|
|
|
#define MAP_SIZE 4096UL
|
|
#define MAP_MASK (MAP_SIZE - 1)
|
|
|
|
int main(int argc, char **argv) {
|
|
int fd;
|
|
void *map_base, *virt_addr;
|
|
unsigned read_result, writeval;
|
|
char *filename;
|
|
off_t target;
|
|
int access_type = 'w';
|
|
|
|
if (argc < 3) {
|
|
// pcimem /sys/bus/pci/devices/0001\:00\:07.0/resource0 0x100 w 0x00
|
|
// argv[0] [1] [2] [3] [4]
|
|
fprintf(stderr,
|
|
"\nUsage:\t%s { sys file } { offset } [ type [ data ] ]\n"
|
|
"\tsys file: sysfs file for the pci resource to act on\n"
|
|
"\toffset : offset into pci memory region to act upon\n"
|
|
"\ttype : access operation type : [b]yte, [h]alfword, [w]ord\n"
|
|
"\tdata : data to be written\n\n",
|
|
argv[0]);
|
|
exit(1);
|
|
}
|
|
|
|
filename = argv[1];
|
|
target = strtoul(argv[2], 0, 0);
|
|
|
|
if (argc > 3)
|
|
access_type = tolower(argv[3][0]);
|
|
|
|
fd = open(filename, O_RDWR | O_SYNC);
|
|
if (fd < 0)
|
|
PRINT_ERROR;
|
|
|
|
printf("%s opened.\n", filename);
|
|
printf("Target offset is %#jx, page size is %lu\n", (uintmax_t)target,
|
|
sysconf(_SC_PAGE_SIZE));
|
|
|
|
fflush(stdout);
|
|
|
|
// Map one page
|
|
printf("mmap(%d, %lu, %#x, %#x, %d, %#jx)\n", 0, MAP_SIZE,
|
|
PROT_READ | PROT_WRITE, MAP_SHARED, fd, (uintmax_t)target);
|
|
|
|
map_base = mmap(0, MAP_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, fd,
|
|
target & ~MAP_MASK);
|
|
|
|
if (map_base == (void *)-1)
|
|
PRINT_ERROR;
|
|
|
|
printf("PCI Memory mapped to address %p.\n", map_base);
|
|
fflush(stdout);
|
|
|
|
virt_addr = (uint8_t *)map_base + (target & MAP_MASK);
|
|
|
|
switch (access_type) {
|
|
case 'b':
|
|
read_result = *((unsigned char *)virt_addr);
|
|
break;
|
|
case 'h':
|
|
read_result = *((unsigned short *)virt_addr);
|
|
break;
|
|
case 'w':
|
|
read_result = *((unsigned int *)virt_addr);
|
|
break;
|
|
default:
|
|
fprintf(stderr, "Illegal data type '%c'.\n", access_type);
|
|
exit(2);
|
|
}
|
|
|
|
printf("Value at offset %#jx (%p): %#x\n", (uintmax_t)target, virt_addr,
|
|
read_result);
|
|
fflush(stdout);
|
|
|
|
if (argc > 4) {
|
|
writeval = strtoul(argv[4], 0, 0);
|
|
switch (access_type) {
|
|
case 'b':
|
|
*((unsigned char *)virt_addr) = writeval;
|
|
read_result = *((unsigned char *)virt_addr);
|
|
break;
|
|
case 'h':
|
|
*((unsigned short *)virt_addr) = writeval;
|
|
read_result = *((unsigned short *)virt_addr);
|
|
break;
|
|
case 'w':
|
|
*((unsigned int *)virt_addr) = writeval;
|
|
read_result = *((unsigned int *)virt_addr);
|
|
break;
|
|
}
|
|
printf("Written %#x; readback %#x\n", writeval, read_result);
|
|
fflush(stdout);
|
|
}
|
|
|
|
if (munmap(map_base, MAP_SIZE) == -1)
|
|
PRINT_ERROR;
|
|
|
|
close(fd);
|
|
|
|
return 0;
|
|
}
|