1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright 2015, Michael Neuling, IBM Corp.
4 * Original: Michael Neuling 19/7/2013
5 * Edited: Rashmica Gupta 01/12/2015
6 *
7 * Do some transactions, see if the tar is corrupted.
8 * If the transaction is aborted, the TAR should be rolled back to the
9 * checkpointed value before the transaction began. The value written to
10 * TAR in suspended mode should only remain in TAR if the transaction
11 * completes.
12 */
13
14#include <stdio.h>
15#include <stdlib.h>
16#include <unistd.h>
17#include <string.h>
18
19#include "tm.h"
20#include "utils.h"
21
22int	num_loops	= 10000;
23
24int test_tar(void)
25{
26	int i;
27
28	SKIP_IF(!have_htm());
29	SKIP_IF(htm_is_synthetic());
30	SKIP_IF(!is_ppc64le());
31
32	for (i = 0; i < num_loops; i++)
33	{
34		uint64_t result = 0;
35		asm __volatile__(
36			"li	7, 1;"
37			"mtspr	%[tar], 7;"	/* tar = 1 */
38			"tbegin.;"
39			"beq	3f;"
40			"li	4, 0x7000;"	/* Loop lots, to use time */
41			"2:;"			/* Start loop */
42			"li	7, 2;"
43			"mtspr	%[tar], 7;"	/* tar = 2 */
44			"tsuspend.;"
45			"li	7, 3;"
46			"mtspr	%[tar], 7;"	/* tar = 3 */
47			"tresume.;"
48			"subi	4, 4, 1;"
49			"cmpdi	4, 0;"
50			"bne	2b;"
51			"tend.;"
52
53			/* Transaction sucess! TAR should be 3 */
54			"mfspr  7, %[tar];"
55			"ori	%[res], 7, 4;"  // res = 3|4 = 7
56			"b	4f;"
57
58			/* Abort handler. TAR should be rolled back to 1 */
59			"3:;"
60			"mfspr  7, %[tar];"
61			"ori	%[res], 7, 8;"	// res = 1|8 = 9
62			"4:;"
63
64			: [res]"=r"(result)
65			: [tar]"i"(SPRN_TAR)
66			   : "memory", "r0", "r4", "r7");
67
68		/* If result is anything else other than 7 or 9, the tar
69		 * value must have been corrupted. */
70		if ((result != 7) && (result != 9))
71			return 1;
72	}
73	return 0;
74}
75
76int main(int argc, char *argv[])
77{
78	/* A low number of iterations (eg 100) can cause a false pass */
79	if (argc > 1) {
80		if (strcmp(argv[1], "-h") == 0) {
81			printf("Syntax:\n\t%s [<num loops>]\n",
82			       argv[0]);
83			return 1;
84		} else {
85			num_loops = atoi(argv[1]);
86		}
87	}
88
89	printf("Starting, %d loops\n", num_loops);
90
91	return test_harness(test_tar, "tm_tar");
92}
93