toaruos/apps/qemu-fwcfg.c
2018-07-17 14:29:26 +09:00

159 lines
3.4 KiB
C

/*
* Tool for reading QEMU fwcfg values.
*/
#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <stdint.h>
#include <string.h>
#include <unistd.h>
#include <getopt.h>
unsigned short inports(unsigned short _port) {
unsigned short rv;
asm volatile ("inw %1, %0" : "=a" (rv) : "dN" (_port));
return rv;
}
void outports(unsigned short _port, unsigned short _data) {
asm volatile ("outw %1, %0" : : "dN" (_port), "a" (_data));
}
unsigned int inportl(unsigned short _port) {
unsigned int rv;
asm volatile ("inl %%dx, %%eax" : "=a" (rv) : "dN" (_port));
return rv;
}
void outportl(unsigned short _port, unsigned int _data) {
asm volatile ("outl %%eax, %%dx" : : "dN" (_port), "a" (_data));
}
unsigned char inportb(unsigned short _port) {
unsigned char rv;
asm volatile ("inb %1, %0" : "=a" (rv) : "dN" (_port));
return rv;
}
void outportb(unsigned short _port, unsigned char _data) {
asm volatile ("outb %1, %0" : : "dN" (_port), "a" (_data));
}
void outportsm(unsigned short port, unsigned char * data, unsigned long size) {
asm volatile ("rep outsw" : "+S" (data), "+c" (size) : "d" (port));
}
void inportsm(unsigned short port, unsigned char * data, unsigned long size) {
asm volatile ("rep insw" : "+D" (data), "+c" (size) : "d" (port) : "memory");
}
void swap_bytes(void * in, int count) {
char * bytes = in;
if (count == 4) {
uint32_t * t = in;
*t = (bytes[0] << 24) | (bytes[1] << 12) | (bytes[2] << 8) | bytes[3];
} else if (count == 2) {
uint16_t * t = in;
*t = (bytes[0] << 8) | bytes[1];
}
}
struct fw_cfg_file {
uint32_t size;
uint16_t select;
uint16_t reserved;
char name[56];
};
int usage(char * argv[]) {
printf(
"usage: %s [-?ln] [config name]\n"
"\n"
" -l \033[3mlist available config entries\033[0m\n"
" -n \033[3mdon't print a new line after image\033[0m\n"
" -? \033[3mshow this help text\033[0m\n"
"\n", argv[0]);
return 1;
}
int main(int argc, char * argv[]) {
int opt = 0;
int list = 0;
int no_newline = 0;
while ((opt = getopt(argc, argv, "?ln")) != -1) {
switch (opt) {
case '?':
return usage(argv);
case 'n':
no_newline = 1;
break;
case 'l':
list = 1;
break;
}
}
if (optind >= argc && !list) {
return usage(argv);
}
outports(0x510, 0x0000);
if (inportb(0x511) != 'Q' ||
inportb(0x511) != 'E' ||
inportb(0x511) != 'M' ||
inportb(0x511) != 'U') {
fprintf(stderr, "%s: this doesn't seem to be qemu\n", argv[0]);
}
uint32_t count = 0;
uint8_t * bytes = (uint8_t *)&count;
outports(0x510,0x0019);
for (int i = 0; i < 4; ++i) {
bytes[i] = inportb(0x511);
}
swap_bytes(&count, 4);
int found = 0;
struct fw_cfg_file file;
uint8_t * tmp = (uint8_t *)&file;
for (unsigned int i = 0; i < count; ++i) {
for (unsigned int j = 0; j < sizeof(struct fw_cfg_file); ++j) {
tmp[j] = inportb(0x511);
}
swap_bytes(&file.size, 4);
swap_bytes(&file.select, 2);
if (list) {
fprintf(stdout, "%s (%d byte%s)\n", file.name, (int)file.size, file.size == 1 ? "" : "s");
} else {
if (!strcmp(file.name, argv[optind])) {
found = 1;
break;
}
}
}
if (found) {
outports(0x510, file.select);
char * tmp = malloc(file.size);
for (unsigned int i = 0; i < 32 && i < file.size; ++i) {
tmp[i] = inportb(0x511);
}
fwrite(tmp, 1, file.size, stdout);
if (!no_newline) {
fprintf(stdout, "\n");
}
} else if (!list) {
fprintf(stderr, "%s: config option not found\n", argv[0]);
return 1;
}
return 0;
}