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(!is_ppc64le());
30
31	for (i = 0; i < num_loops; i++)
32	{
33		uint64_t result = 0;
34		asm __volatile__(
35			"li	7, 1;"
36			"mtspr	%[tar], 7;"	/* tar = 1 */
37			"tbegin.;"
38			"beq	3f;"
39			"li	4, 0x7000;"	/* Loop lots, to use time */
40			"2:;"			/* Start loop */
41			"li	7, 2;"
42			"mtspr	%[tar], 7;"	/* tar = 2 */
43			"tsuspend.;"
44			"li	7, 3;"
45			"mtspr	%[tar], 7;"	/* tar = 3 */
46			"tresume.;"
47			"subi	4, 4, 1;"
48			"cmpdi	4, 0;"
49			"bne	2b;"
50			"tend.;"
51
52			/* Transaction sucess! TAR should be 3 */
53			"mfspr  7, %[tar];"
54			"ori	%[res], 7, 4;"  // res = 3|4 = 7
55			"b	4f;"
56
57			/* Abort handler. TAR should be rolled back to 1 */
58			"3:;"
59			"mfspr  7, %[tar];"
60			"ori	%[res], 7, 8;"	// res = 1|8 = 9
61			"4:;"
62
63			: [res]"=r"(result)
64			: [tar]"i"(SPRN_TAR)
65			   : "memory", "r0", "r4", "r7");
66
67		/* If result is anything else other than 7 or 9, the tar
68		 * value must have been corrupted. */
69		if ((result != 7) && (result != 9))
70			return 1;
71	}
72	return 0;
73}
74
75int main(int argc, char *argv[])
76{
77	/* A low number of iterations (eg 100) can cause a false pass */
78	if (argc > 1) {
79		if (strcmp(argv[1], "-h") == 0) {
80			printf("Syntax:\n\t%s [<num loops>]\n",
81			       argv[0]);
82			return 1;
83		} else {
84			num_loops = atoi(argv[1]);
85		}
86	}
87
88	printf("Starting, %d loops\n", num_loops);
89
90	return test_harness(test_tar, "tm_tar");
91}
92