cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

spidev_fdx.c (2798B)

      1// SPDX-License-Identifier: GPL-2.0
      2#include <stdio.h>
      3#include <unistd.h>
      4#include <stdlib.h>
      5#include <fcntl.h>
      6#include <string.h>
      7
      8#include <sys/ioctl.h>
      9#include <sys/types.h>
     10#include <sys/stat.h>
     11
     12#include <linux/types.h>
     13#include <linux/spi/spidev.h>
     14
     15
     16static int verbose;
     17
     18static void do_read(int fd, int len)
     19{
     20	unsigned char	buf[32], *bp;
     21	int		status;
     22
     23	/* read at least 2 bytes, no more than 32 */
     24	if (len < 2)
     25		len = 2;
     26	else if (len > sizeof(buf))
     27		len = sizeof(buf);
     28	memset(buf, 0, sizeof buf);
     29
     30	status = read(fd, buf, len);
     31	if (status < 0) {
     32		perror("read");
     33		return;
     34	}
     35	if (status != len) {
     36		fprintf(stderr, "short read\n");
     37		return;
     38	}
     39
     40	printf("read(%2d, %2d): %02x %02x,", len, status,
     41		buf[0], buf[1]);
     42	status -= 2;
     43	bp = buf + 2;
     44	while (status-- > 0)
     45		printf(" %02x", *bp++);
     46	printf("\n");
     47}
     48
     49static void do_msg(int fd, int len)
     50{
     51	struct spi_ioc_transfer	xfer[2];
     52	unsigned char		buf[32], *bp;
     53	int			status;
     54
     55	memset(xfer, 0, sizeof xfer);
     56	memset(buf, 0, sizeof buf);
     57
     58	if (len > sizeof buf)
     59		len = sizeof buf;
     60
     61	buf[0] = 0xaa;
     62	xfer[0].tx_buf = (unsigned long)buf;
     63	xfer[0].len = 1;
     64
     65	xfer[1].rx_buf = (unsigned long) buf;
     66	xfer[1].len = len;
     67
     68	status = ioctl(fd, SPI_IOC_MESSAGE(2), xfer);
     69	if (status < 0) {
     70		perror("SPI_IOC_MESSAGE");
     71		return;
     72	}
     73
     74	printf("response(%2d, %2d): ", len, status);
     75	for (bp = buf; len; len--)
     76		printf(" %02x", *bp++);
     77	printf("\n");
     78}
     79
     80static void dumpstat(const char *name, int fd)
     81{
     82	__u8	lsb, bits;
     83	__u32	mode, speed;
     84
     85	if (ioctl(fd, SPI_IOC_RD_MODE32, &mode) < 0) {
     86		perror("SPI rd_mode");
     87		return;
     88	}
     89	if (ioctl(fd, SPI_IOC_RD_LSB_FIRST, &lsb) < 0) {
     90		perror("SPI rd_lsb_fist");
     91		return;
     92	}
     93	if (ioctl(fd, SPI_IOC_RD_BITS_PER_WORD, &bits) < 0) {
     94		perror("SPI bits_per_word");
     95		return;
     96	}
     97	if (ioctl(fd, SPI_IOC_RD_MAX_SPEED_HZ, &speed) < 0) {
     98		perror("SPI max_speed_hz");
     99		return;
    100	}
    101
    102	printf("%s: spi mode 0x%x, %d bits %sper word, %d Hz max\n",
    103		name, mode, bits, lsb ? "(lsb first) " : "", speed);
    104}
    105
    106int main(int argc, char **argv)
    107{
    108	int		c;
    109	int		readcount = 0;
    110	int		msglen = 0;
    111	int		fd;
    112	const char	*name;
    113
    114	while ((c = getopt(argc, argv, "hm:r:v")) != EOF) {
    115		switch (c) {
    116		case 'm':
    117			msglen = atoi(optarg);
    118			if (msglen < 0)
    119				goto usage;
    120			continue;
    121		case 'r':
    122			readcount = atoi(optarg);
    123			if (readcount < 0)
    124				goto usage;
    125			continue;
    126		case 'v':
    127			verbose++;
    128			continue;
    129		case 'h':
    130		case '?':
    131usage:
    132			fprintf(stderr,
    133				"usage: %s [-h] [-m N] [-r N] /dev/spidevB.D\n",
    134				argv[0]);
    135			return 1;
    136		}
    137	}
    138
    139	if ((optind + 1) != argc)
    140		goto usage;
    141	name = argv[optind];
    142
    143	fd = open(name, O_RDWR);
    144	if (fd < 0) {
    145		perror("open");
    146		return 1;
    147	}
    148
    149	dumpstat(name, fd);
    150
    151	if (msglen)
    152		do_msg(fd, msglen);
    153
    154	if (readcount)
    155		do_read(fd, readcount);
    156
    157	close(fd);
    158	return 0;
    159}